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Shahid M, Sglavo VM. Binder Jetting 3D Printing of Binary Cement-Siliceous Sand Mixture. Materials (Basel) 2024; 17:1514. [PMID: 38612029 PMCID: PMC11012532 DOI: 10.3390/ma17071514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 03/18/2024] [Accepted: 03/23/2024] [Indexed: 04/14/2024]
Abstract
Three-dimensional printing allows accurate geometries to be obtained across a wide range of applications and it is now also moving into the architecture and construction industry. In the present work, a unique binary mix composed of ordinary Portland cement (OPC) and quick-setting cement (QSC) was combined with silica sand aggregate in different proportions for a customized binder jetting 3D printing (BJ3DP) process. Specimens were printed using the blended dry powders and deionized water to determine the impact of the processing variables on the properties of the realized specimens. The results show that the properties are influenced by the binary mix proportions and the layer thickness. The investigation found significant improvement in mechanical performance on increasing the proportion of OPC and optimal conditions were identified with proportions of 35 wt% OPC and 5 wt% QSC. Notable enhancements were also observed as the layer thickness was reduced.
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Affiliation(s)
- Mursaleen Shahid
- Department of Industrial Engineering, University of Trento, 38123 Trento, Italy
| | - Vincenzo M. Sglavo
- Department of Industrial Engineering, University of Trento, 38123 Trento, Italy
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2
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Zhao Z, El-Naggar A, Kau J, Olson C, Tomlinson D, Chang SX. Biochar affects compressive strength of Portland cement composites: a meta-analysis. Biochar 2024; 6:21. [PMID: 38463456 PMCID: PMC10917841 DOI: 10.1007/s42773-024-00309-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Revised: 02/15/2024] [Accepted: 02/21/2024] [Indexed: 03/12/2024]
Abstract
One strategy to reduce CO2 emissions from cement production is to reduce the amount of Portland cement produced by replacing it with supplementary cementitious materials (SCMs). Biochar is a potential SCM that is an eco-friendly and stable porous pyrolytic material. However, the effects of biochar addition on the performances of Portland cement composites are not fully understood. This meta-analysis investigated the impact of biochar addition on the 7- and 28-day compressive strength of Portland cement composites based on 606 paired observations. Biochar feedstock type, pyrolysis conditions, pre-treatments and modifications, biochar dosage, and curing type all influenced the compressive strength of Portland cement composites. Biochars obtained from plant-based feedstocks (except rice and hardwood) improved the 28-day compressive strength of Portland cement composites by 3-13%. Biochars produced at pyrolysis temperatures higher than 450 °C, with a heating rate of around 10 C min-1, increased the 28-day compressive strength more effectively. Furthermore, the addition of biochar with small particle sizes increased the compressive strength of Portland cement composites by 2-7% compared to those without biochar addition. Biochar dosage of < 2.5% of the binder weight enhanced both compressive strengths, and common curing methods maintained the effect of biochar addition. However, when mixing the cement, adding fine and coarse aggregates such as sand and gravel affects the concrete and mortar's compressive strength, diminishing the effect of biochar addition and making the biochar effect nonsignificant. We concluded that appropriate biochar addition could maintain or enhance the mechanical performance of Portland cement composites, and future research should explore the mechanisms of biochar effects on the performance of cement composites. Graphical Abstract Supplementary Information The online version contains supplementary material available at 10.1007/s42773-024-00309-2.
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Affiliation(s)
- Zhihao Zhao
- Department of Renewable Resources, University of Alberta, 442 Earth Sciences Building, Edmonton, AB T6G 2E3 Canada
| | - Ali El-Naggar
- Department of Renewable Resources, University of Alberta, 442 Earth Sciences Building, Edmonton, AB T6G 2E3 Canada
- Department of Soil Sciences, Faculty of Agriculture, Ain Shams University, Cairo, 11241 Egypt
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou, Zhejiang, 311300 China
| | - Johnson Kau
- Department of Civil Engineering, University of Alberta, 6-255 Donadeo Innovation Centre For Engineering, Edmonton Alberta, T6G 2H5 Canada
| | - Chris Olson
- Innovative Reduction Strategies Inc, Northtown PO, PO Box 71022, Edmonton Alberta, AB T5E 6J8 Canada
| | - Douglas Tomlinson
- Department of Civil Engineering, University of Alberta, 6-255 Donadeo Innovation Centre For Engineering, Edmonton Alberta, T6G 2H5 Canada
| | - Scott X. Chang
- Department of Renewable Resources, University of Alberta, 442 Earth Sciences Building, Edmonton, AB T6G 2E3 Canada
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Alves BIA, Marvila MT, Linhares Júnior JAT, Vieira CMF, Alexandre J, de Azevedo ARG. Alkaline Activation of Binders: A Comparative Study. Materials (Basel) 2024; 17:667. [PMID: 38591511 PMCID: PMC10856149 DOI: 10.3390/ma17030667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 01/24/2024] [Accepted: 01/27/2024] [Indexed: 04/10/2024]
Abstract
Binders formulated with activated alkali materials to replace Portland cement, which has high polluting potential due to CO2 emissions in its manufacture, have increasingly been developed. The objective of this study is to evaluate the main properties of activated alkali materials (AAM) produced by blast furnace slag, fly ash, and metakaolin. Initially, binders were characterized by their chemical, mineralogical and granulometric composition. Later, specimens were produced, with molarity variation between 4.00 and 5.50, using the binders involved in the research. In preparing the activating solution, sodium hydroxide and silicate were used. The evaluated properties of AAM were consistency, viscosity, water absorption, density, compressive strength (7 days of cure), calorimetry, mineralogical analysis by X-ray diffraction, and morphological analysis by scanning electron microscopy. The results of evaluation in the fresh state demonstrate that metakaolin has the lowest workability indices of the studied AAM. The results observed in the hardened state indicate that the metakaolin activation process is optimized with normal cure and molarity of 4.0 and 4.5 mol/L, obtaining compressive strength results after 7 days of curing of approximately 30 MPa. The fly ash activation process is the least intense among the evaluated binders. This can be seen from the absence of phases formed in the XRD in the compositions containing fly ash as binder. Unlike blast furnace slag and metakaolin, the formation of sodalite, faujasite or tobermorite is not observed. Finally, the blast furnace slag displays more intense reactivity during thermal curing, obtaining compressive strength results after 7 days of curing of around 25 MPa. This is because the material's reaction kinetics are low but can be increased in an alkaline environment, and by the effect of temperature. From these results, it is concluded that each precursor has its own activation mechanism, observed by the techniques used in this research. From the results obtained in this study, it is expected that the alkaline activation process of the types of binders evaluated herein will become a viable alternative for replacing Portland cement, thus contributing to cement technology and other cementitious materials.
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Affiliation(s)
- Bianca Ignacio Almeida Alves
- LAMAV—Advanced Materials Laboratory, UENF—University of the Northern Rio de Janeiro, Av. Alberto Lamego, 2000, Campos dos Goytacazes 28013-602, Brazil; (B.I.A.A.); (J.A.T.L.J.); (C.M.F.V.)
| | - Markssuel Teixeira Marvila
- Rio Paranaíba Campus, UFV—Federal University of Viçosa, Rodovia BR 230 Km 7, Rio Paranaíba 38810-000, Brazil;
| | - José Alexandre Tostes Linhares Júnior
- LAMAV—Advanced Materials Laboratory, UENF—University of the Northern Rio de Janeiro, Av. Alberto Lamego, 2000, Campos dos Goytacazes 28013-602, Brazil; (B.I.A.A.); (J.A.T.L.J.); (C.M.F.V.)
| | - Carlos Maurício Fontes Vieira
- LAMAV—Advanced Materials Laboratory, UENF—University of the Northern Rio de Janeiro, Av. Alberto Lamego, 2000, Campos dos Goytacazes 28013-602, Brazil; (B.I.A.A.); (J.A.T.L.J.); (C.M.F.V.)
| | - Jonas Alexandre
- LECIV—Civil Engineering Laboratory, UENF—State University of the Northern Rio de Janeiro, Av. Alberto Lamego, 2000, Campos dos Goytacazes 28013-602, Brazil;
| | - Afonso Rangel Garcez de Azevedo
- LECIV—Civil Engineering Laboratory, UENF—State University of the Northern Rio de Janeiro, Av. Alberto Lamego, 2000, Campos dos Goytacazes 28013-602, Brazil;
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Ochoa WAA, Málaga MAS, Tapia AB, Calabokis OP, Nuñez de la Rosa YE, Viscarra Chirinos GE, Pinto Lavayén SN. Evaluation of Compressive and Bending Strength of a Geopolymer Based on Lateritic Clays as an Alternative Hydraulic Binder. Materials (Basel) 2024; 17:307. [PMID: 38255475 PMCID: PMC10820368 DOI: 10.3390/ma17020307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 12/17/2023] [Accepted: 12/29/2023] [Indexed: 01/24/2024]
Abstract
In Bolivia, lateritic soils are common in humid tropical regions and can be used in the construction industry as an alternative to materials that cause a negative environmental impact, such as cement. The production of Portland cement causes environmental issues like significant greenhouse gas emissions and air pollution. To address this problem, geopolymers have been introduced as an alternative binder with low CO2 emissions. In this regard, geopolymers based on lateritic clays have been studied mineralogically, chemically, and on their compressive strength separately. However, there are still no studies on lateritic clays present in Bolivia and their mechanical, mineralogical, and chemical properties combined in a geopolymer. Therefore, this present research proposes the evaluation of a geopolymer made from laterite clays. Compression and flexural tests were carried out, along with mineralogical and chemical analyses on mortar and geopolymer cubes and prisms. The results indicate that the laterite clay-based geopolymer has lower compressive strength compared to Portland cement IP (cement type I with the addition of pozzolana) mortar. However, the flexural strength tests show a slight increase in the case of the geopolymer.
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Affiliation(s)
- Walter A. Abujder Ochoa
- Universidad Católica Boliviana San Pablo, Departamento de Ingenierías y Ciencias Exactas, Centro de Investigación en Ciencias Exactas e Ingenierías (CICEI), C. Márquez, Esq. Parque Jorge Trigo Andia, Tupuraya, Cochabamba, Bolivia; (M.A.S.M.); (A.B.T.); (G.E.V.C.); (S.N.P.L.)
| | - Moisés A. Sánchez Málaga
- Universidad Católica Boliviana San Pablo, Departamento de Ingenierías y Ciencias Exactas, Centro de Investigación en Ciencias Exactas e Ingenierías (CICEI), C. Márquez, Esq. Parque Jorge Trigo Andia, Tupuraya, Cochabamba, Bolivia; (M.A.S.M.); (A.B.T.); (G.E.V.C.); (S.N.P.L.)
| | - Arturo Brañez Tapia
- Universidad Católica Boliviana San Pablo, Departamento de Ingenierías y Ciencias Exactas, Centro de Investigación en Ciencias Exactas e Ingenierías (CICEI), C. Márquez, Esq. Parque Jorge Trigo Andia, Tupuraya, Cochabamba, Bolivia; (M.A.S.M.); (A.B.T.); (G.E.V.C.); (S.N.P.L.)
| | - Oriana Palma Calabokis
- Faculty of Engineering and Basic Sciences, Fundación Universitaria Los Libertadores, Bogotá 1112211, Colombia;
| | - Yamid E. Nuñez de la Rosa
- Faculty of Engineering and Basic Sciences, Fundación Universitaria Los Libertadores, Bogotá 1112211, Colombia;
| | - Gunther E. Viscarra Chirinos
- Universidad Católica Boliviana San Pablo, Departamento de Ingenierías y Ciencias Exactas, Centro de Investigación en Ciencias Exactas e Ingenierías (CICEI), C. Márquez, Esq. Parque Jorge Trigo Andia, Tupuraya, Cochabamba, Bolivia; (M.A.S.M.); (A.B.T.); (G.E.V.C.); (S.N.P.L.)
| | - Sebastián N. Pinto Lavayén
- Universidad Católica Boliviana San Pablo, Departamento de Ingenierías y Ciencias Exactas, Centro de Investigación en Ciencias Exactas e Ingenierías (CICEI), C. Márquez, Esq. Parque Jorge Trigo Andia, Tupuraya, Cochabamba, Bolivia; (M.A.S.M.); (A.B.T.); (G.E.V.C.); (S.N.P.L.)
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Sugama T, Pyatina T. Hydrophobic, Thermal Shock-and-Corrosion-Resistant XSBR Latex-Modified Lightweight Class G Cement Composites in Geothermal Well Energy Storage Systems. Materials (Basel) 2023; 16:5792. [PMID: 37687483 PMCID: PMC10489030 DOI: 10.3390/ma16175792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 08/09/2023] [Accepted: 08/17/2023] [Indexed: 09/10/2023]
Abstract
Energy losses can be significantly reduced if thermally insulating cement is used for energy storage and recovery. The thermal conductivity (TC) of the currently used cement is between 1 and 1.2 W/mK. In this study we assessed the ability of polystyrene (PS)-polybutadiene (PB)-polyacrylic acid (PAA) terpolymer (cross-linked styrene-butadiene rubber, XSBR) latex to improve thermal insulating properties and thermal shock (TS) resistance of class G ordinary Portland cement (OPC) and fly ash cenosphere (FCSs) composites in the temperature range of 100-175 °C. The composites autoclaved at 100 °C were subjected to three cycles, one cycle: 175 °C heat → 25 °C water quenching). In hydrothermal and thermal (TS) environments at elevated temperatures in cement slurries the XSBR latex formed acrylic calcium complexes through acid-base reactions, and the number of such complexes increased at higher temperatures due to the XSBR degradation with formation of additional acrylic groups. As a result, these complexes offered the following five advanced properties to the OPC-based composites: (1) enhanced hydrophobicity; (2) decreased water-fillable porosity; (3) reduced TC for water-saturated composites; (4) minimized loss of compressive strength, Young's modulus, and compressive fracture toughness after TS; and (5) abated pozzolanic activity of FCSs, which allowed FCSs to persist as thermal insulators under strongly alkaline conditions of cement slurries. Additionally, XSBR-modified slurries possessed improved workability and decreased slurry density due to the air-entraining effect of latex, which resulted in further improvement of thermal insulation performance of the modified composites.
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Martins GLO, Fraga YSB, de Paula A, Rêgo JHDS, Terrades AM, Rojas MF. Analysis of the Microstructure and Porosity of Cement Pastes with Functionalized Nanosilica with Different Contents of Aminosilane. Materials (Basel) 2023; 16:5675. [PMID: 37629966 PMCID: PMC10456893 DOI: 10.3390/ma16165675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 08/10/2023] [Accepted: 08/14/2023] [Indexed: 08/27/2023]
Abstract
This research aims to analyze the effect of functionalized nanosilica (NSF) with different levels of amine groups in the formation of hydration products. Four cement pastes were investigated, one reference with Portland cement and three replacing 1% of Portland cement by nanosilica (NS), NSF with a low content of amine groups, and NSF with a high content of amine groups. The heat of hydration of the pastes was evaluated up to 7 days of hydration, the amount of calcium hydroxide (CH) and hydrated phases by means of the thermogravimetric analysis (TGA) test and compressive strength at 2, 7, and 28 days, and porosity through tests of mercury intrusion porosimetry and computed tomography at 28 days of hydration. It was possible to observe that the NSF directly influenced the hydration kinetics of the pastes, delaying the hydration of the Portland cement; however, it demonstrated a similar mechanical performance to the paste with NS at 2 days of hydration and an increase of 10% at 28 days of hydration due to the improvement in the hydration process. Thus, it is possible to conclude that the functionalization of NSF with a low 3-aminopropyltriethoxysilane (APTES) content is promising for use in cementitious materials and may improve hydration and mechanical performance at more advanced ages compared to NS.
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Affiliation(s)
- Gabriel Lima Oliveira Martins
- Department of Civil and Environmental Construction, University of Brasília, Brasilia 70910-900, Brazil; (G.L.O.M.); (Y.S.B.F.); (A.d.P.); (J.H.d.S.R.)
| | - Yuri Sotero Bomfim Fraga
- Department of Civil and Environmental Construction, University of Brasília, Brasilia 70910-900, Brazil; (G.L.O.M.); (Y.S.B.F.); (A.d.P.); (J.H.d.S.R.)
- Center for Exact and Technological Sciences, Federal University of Acre, Rio Branco 69920-900, Brazil
| | - Andréia de Paula
- Department of Civil and Environmental Construction, University of Brasília, Brasilia 70910-900, Brazil; (G.L.O.M.); (Y.S.B.F.); (A.d.P.); (J.H.d.S.R.)
| | - João Henrique da Silva Rêgo
- Department of Civil and Environmental Construction, University of Brasília, Brasilia 70910-900, Brazil; (G.L.O.M.); (Y.S.B.F.); (A.d.P.); (J.H.d.S.R.)
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Tale Ponga D, Sabziparvar A, Cousin P, Boulos L, Robert M, Foruzanmehr MR. Retarding Effect of Hemp Hurd Lixiviates on the Hydration of Hydraulic and CSA Cements. Materials (Basel) 2023; 16:5561. [PMID: 37629852 PMCID: PMC10456383 DOI: 10.3390/ma16165561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Revised: 07/30/2023] [Accepted: 08/02/2023] [Indexed: 08/27/2023]
Abstract
Wood wool panels are widely used in the construction industry as sustainable cementitious composites, but there is a growing need to replace traditional Portland cement with a binder that has a lower embodied carbon footprint. In addition, the sustainability of these panels may face serious impediments if the required amount of wood for their production needs a harvest rate higher than the rate at which the tree sources reach maturity. One solution is to use the wooden part of fast-growing plants such as hemp. However, the compounds extracted from the mixture of plants and water are the main cause of the delay observed during the hydration process of hydraulic binders in these cementitious composites. The objective of this study is to evaluate the effect of bio-aggregate lixiviates (hemp hurd) on the hydration kinetics of calcium sulfoaluminate (CSA) cement as a low-embodied-carbon alternative to ordinary Portland cement (OPC). The isothermal calorimeter showed that the hemp hurd lixiviate caused a greater delay in GU's hydration process than CSA's. At a 5% concentration, the main hydration peak for GU cement emerged after 91 h, whereas for CSA cement, it appeared much earlier, at 2.5 h. XRD and TGA analysis showed that after 12 h of hydration, hydration products such as calcium silicate hydrates (C-S-H) and portlandite (CH) were not able to form on GU cement, indicating low hydration of silicate products. Moreover, at 5% concentration, the carbonation of ettringite was observed in CSA cement. The compressive strength values obtained from the mixes containing hemp hurd lixiviate consistently showed lower values compared to the reference samples prepared with distilled water. Furthermore, the CSA samples demonstrated superior compressive strength when compared to the GU samples. After 28 days of hydration, the compressive strength values for CSA cement were 36.7%, 63.5% and 71% higher than GU cement at a concentration of 0.5%, 2% and 5% hemp hurd lixiviate, respectively.
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Affiliation(s)
- Donato Tale Ponga
- Department of Civil & Building Engineering, University of Sherbrooke, Sherbrooke, QC J1K 2R1, Canada; (D.T.P.); (P.C.); (L.B.); (M.R.)
| | | | - Patrice Cousin
- Department of Civil & Building Engineering, University of Sherbrooke, Sherbrooke, QC J1K 2R1, Canada; (D.T.P.); (P.C.); (L.B.); (M.R.)
| | - Lina Boulos
- Department of Civil & Building Engineering, University of Sherbrooke, Sherbrooke, QC J1K 2R1, Canada; (D.T.P.); (P.C.); (L.B.); (M.R.)
| | - Mathieu Robert
- Department of Civil & Building Engineering, University of Sherbrooke, Sherbrooke, QC J1K 2R1, Canada; (D.T.P.); (P.C.); (L.B.); (M.R.)
| | - M. Reza Foruzanmehr
- Department of Civil Engineering, University of Ottawa, Ottawa, ON K1N 6N5, Canada;
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Bonfil D, Veleva L, Feliu S, Escalante-García JI. Corrosion Activity of Stainless Steel SS430 and Carbon Steel B450C in a Sodium Silicate Modified Limestone- Portland Cement Extract. Materials (Basel) 2023; 16:5066. [PMID: 37512340 PMCID: PMC10385683 DOI: 10.3390/ma16145066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 06/29/2023] [Accepted: 07/10/2023] [Indexed: 07/30/2023]
Abstract
Stainless steel SS430 and carbon steel B450C were exposed for 30 days to the aqueous extract of sodium silicate-modified limestone-Portland cement as an alternative for the partial replacement of the Portland cement clinker. The initial pH of 12.60 was lowered and maintained at an average of 9.60, associated with air CO2 dissolution and acidification. As a result, the carbon steel lost its passive state, and the corrosion potential (OCP) reached a negative value of up to 296 mV, forming the corrosion layer of FeO, and FeOOH. In the meaning time, on the stainless steel SS430 surface, a passive layer of Cr2O3 grew in the presence of FeO, Fe2O3 and Cr(OH)3 corrosion products; thus, the OCP shifted to more positive values of +150 mV. It is suggested that a self-repassivation process took place on the SS430 surface due to the accumulation of alkaline sulfates on the interface. Because of the chloride attack, SS430 presented isolated pits, while on B450C, their area was extended. The quantitative analysis of EIS Nyquist and Bode diagrams revealed that the Rp of the corrosion process for SS430 was 2500 kΩcm2, ≈32 times lower in magnitude than on B450C, for which the passive layer tended to disappear, while that on SS430 was ≈0.82 nm.
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Affiliation(s)
- David Bonfil
- Center for Research and Advances Study (CINVESTAV), Applied Physics Department, Campus Merida, Merida 97310, Mexico
| | - Lucien Veleva
- Center for Research and Advances Study (CINVESTAV), Applied Physics Department, Campus Merida, Merida 97310, Mexico
| | - Sebastian Feliu
- National Center for Metallurgical Research (CENIM-CSIC), Surface Engineering Corrosion and Durability Department, 8040 Madrid, Spain
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Silva VP, Carvalho RDA, Rêgo JHDS, Evangelista F. Machine Learning-Based Prediction of the Compressive Strength of Brazilian Concretes: A Dual-Dataset Study. Materials (Basel) 2023; 16:4977. [PMID: 37512252 PMCID: PMC10381529 DOI: 10.3390/ma16144977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 06/10/2023] [Accepted: 06/11/2023] [Indexed: 07/30/2023]
Abstract
Lately, several machine learning (ML) techniques are emerging as alternative and efficient ways to predict how component properties influence the properties of the final mixture. In the area of civil engineering, recent research already uses ML techniques with conventional concrete dosages. The importance of discussing its use in the Brazilian context is inserted in an international context in which this methodology is already being applied, and it is necessary to verify the applicability of these techniques with national databases or what is created from national input data. In this research, one of these techniques, an artificial neural network (ANN), is used to determine the compressive strength of conventional Brazilian concrete at 7 and 28 days by using a database built through publications in congresses and academic works and comparing it with the reference database of Yeh. The data were organized into nine variables in which the data samples for training and test sets vary in five different cases. The eight possible input variables were: consumption of cement, blast furnace slag, pozzolana, water, additive, fine aggregate, coarse aggregate, and age. The response variable was the compressive strength of the concrete. Using international data as a training set and Brazilian data as a test set, or vice versa, did not show satisfactory results in isolation. The results showed a variation in the five scenarios; however, when using the Brazilian and the reference data sets together as test and training sets, higher R2 values were obtained, showing that in the union of the two databases, a good predictive model is obtained.
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Affiliation(s)
- Vitor Pereira Silva
- Department of Civil and Environmental Engineering, SG-12, University of Brasília (UnB), Brasilia 70910-900, Brazil
| | - Ruan de Alencar Carvalho
- Department of Civil and Environmental Engineering, SG-12, University of Brasília (UnB), Brasilia 70910-900, Brazil
| | - João Henrique da Silva Rêgo
- Department of Civil and Environmental Engineering, SG-12, University of Brasília (UnB), Brasilia 70910-900, Brazil
| | - Francisco Evangelista
- Department of Civil and Environmental Engineering, SG-12, University of Brasília (UnB), Brasilia 70910-900, Brazil
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Dvorkin L, Konkol J, Marchuk V, Huts A. Efficient, Fine-Grained Fly Ash Concrete Based on Metal and Basalt Fibers. Materials (Basel) 2023; 16:ma16113969. [PMID: 37297105 DOI: 10.3390/ma16113969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2023] [Revised: 05/22/2023] [Accepted: 05/24/2023] [Indexed: 06/12/2023]
Abstract
This article presents the results of a study of the physical and mechanical properties of fine-grained fly ash concrete based on a combined reinforcement with steel and basalt fibers. The main studies were conducted using mathematical planning of experiments, which allowed the experiments to be algorithmized in terms of both the amount of experimental work and statistical requirements. Quantitative dependences characterizing the effect of the content of cement, fly ash binder, steel, and basalt fiber on the compressive strength and tensile splitting strength of fiber-reinforced concrete were obtained. It has been shown that the use of fiber can increase the efficiency factor of dispersed reinforcement (the tensile splitting strength to compressive strength ratio). To increase the resistance of basalt fiber, it is proposed to use fly ash in cement systems, which reduces the amount of free lime in the hydrating cement environment.
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Affiliation(s)
- Leonid Dvorkin
- Institute of Civil Engineering and Architecture, National University of Water and Environmental Engineering, 33028 Rivne, Ukraine
| | - Janusz Konkol
- Faculty of Civil and Environmental Engineering and Architecture, Rzeszow University of Technology, 35959 Rzeszow, Poland
| | - Vitaliy Marchuk
- Institute of Civil Engineering and Architecture, National University of Water and Environmental Engineering, 33028 Rivne, Ukraine
| | - Andriy Huts
- Faculty of Civil and Environmental Engineering and Architecture, Rzeszow University of Technology, 35959 Rzeszow, Poland
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Zapata-Padilla JR, Juárez-Alvarado CA, Durán-Herrera A, Baltazar-Zamora MA, Terán-Torres BT, Vázquez-Leal FR, Mendoza-Rangel JM. Portland Cement-Based Grouts Enhanced with Basalt Fibers for Post-Tensioned Concrete Duct Filling. Materials (Basel) 2023; 16:2842. [PMID: 37049136 PMCID: PMC10096316 DOI: 10.3390/ma16072842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 03/21/2023] [Accepted: 03/27/2023] [Indexed: 06/19/2023]
Abstract
In post-tensioned systems, grouts act as a last line of defense to prevent the penetration of harmful compounds such as chlorides, moisture and other substances that cause corrosion in the prestressing steel. For this reason, improving grouts results in the enhancement of the overall durability of the structure. In this study, the physical properties of grouts with basalt microfiber additions in the amounts of 0.03, 0.07 and 0.10% with respect to the mix volume were evaluated. The fresh properties included flowability and unit mass. Specimens were fabricated to evaluate drying shrinkage, compressive strength, air permeability and rapid permeability to chloride ions. The incorporation of basalt microfibers showed a beneficial effect on the physical properties of the grout by increasing the drying shrinkage resistance and decreasing the permeability compared to the reference mix and two commercial dry prepackaged grouts. The optimal grout mix was the one with a percentage of basalt microfibers of 0.10%, which decreased drying shrinkage by 15.98% at 14 days compared to the reference mix, and permeability to chloride ions decreased by 10.82% compared to the control mix.
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Affiliation(s)
- José R. Zapata-Padilla
- Facultad de Ingeniería Civil, Universidad Autónoma de Nuevo León, Av. Universidad S/N, San Nicolás de los Garza 66455, Mexico
| | - César A. Juárez-Alvarado
- Facultad de Ingeniería Civil, Universidad Autónoma de Nuevo León, Av. Universidad S/N, San Nicolás de los Garza 66455, Mexico
| | - Alejandro Durán-Herrera
- Facultad de Ingeniería Civil, Universidad Autónoma de Nuevo León, Av. Universidad S/N, San Nicolás de los Garza 66455, Mexico
| | - Miguel A. Baltazar-Zamora
- Facultad de Ingeniería Civil-Xalapa, Universidad Veracruzana, Lomas del Estadio S/N, Zona Universitaria Xalapa, Veracruz 91000, Mexico
| | - Bernardo. T. Terán-Torres
- Facultad de Ingeniería Civil, Universidad Autónoma de Nuevo León, Av. Universidad S/N, San Nicolás de los Garza 66455, Mexico
| | - Francisco R. Vázquez-Leal
- Facultad de Ingeniería Civil, Universidad Autónoma de Nuevo León, Av. Universidad S/N, San Nicolás de los Garza 66455, Mexico
| | - José M. Mendoza-Rangel
- Facultad de Ingeniería Civil, Universidad Autónoma de Nuevo León, Av. Universidad S/N, San Nicolás de los Garza 66455, Mexico
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12
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Abed D, Bchara J, Bshara N. Vital Pulpotomy on immature lower first permanent molars using Portland cement, a case of failure and success-case report with 2 years follow-up. Clin Case Rep 2023; 11:e7272. [PMID: 37124546 PMCID: PMC10130414 DOI: 10.1002/ccr3.7272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 03/14/2023] [Accepted: 04/12/2023] [Indexed: 05/02/2023] Open
Abstract
Key clinical message While the importance of vital pulp therapy comes from its ability to promote pulp healing allowing the tooth to continue its development and giving the patient a more convenient treatment, dental practitioners should be more aware of the minor mistakes which they might commit during treatment procedures that could reflect negatively on the treatment's outcome. Developing behavior management skills as well as learning from reported mistakes are beneficial to practitioners to provide a more precise and successful treatment. Abstract Vital pulp therapies are known to preserve tooth development and give pulp tissues a chance to heal. Despite the progress of biocompatible materials used in this field, these treatments are still facing some failure for several known and unknown reasons that might not only be related to the material used. This case report presents and discusses the possible reasons for the success of one vital pulpotomy procedure and the failure of another, both conducted on two immature lower first permanent molars of the same patient, in an attempt to conclude what led to both results.
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Affiliation(s)
- Dajma Abed
- Department of Pediatric Dentistry, Faculty of DentistryDamascus UniversityDamascusSyria
| | - Jamila Bchara
- Department of Pediatric Dentistry, Faculty of DentistryDamascus UniversityDamascusSyria
| | - Nada Bshara
- Department of Pediatric Dentistry, Faculty of DentistryDamascus UniversityDamascusSyria
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13
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Dvorkin L, Zhitkovsky V, Makarenko R, Ribakov Y. The Influence of Polymer Superplasticizers on Properties of High-Strength Concrete Based on Low-Clinker Slag Portland Cement. Materials (Basel) 2023; 16:2075. [PMID: 36903191 PMCID: PMC10003948 DOI: 10.3390/ma16052075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 03/01/2023] [Accepted: 03/01/2023] [Indexed: 06/18/2023]
Abstract
The paper deals with the effectiveness of various types of polymers (naphthalene formaldehyde, polycarboxylate, and lignosulfonate) as superplasticizers of concrete mixtures based on low-clinker slag Portland cement. Using the mathematical planning experimental method and statistical models of water demand of concrete mixtures with polymer superplasticizers, as well as concrete strength at different ages and under different curing conditions (normal curing and after steaming) were obtained. According to the models, the superplasticizer's water-reducing effect and relative change in concrete strength were obtained. The proposed criterion for evaluating the effectiveness and compatibility of superplasticizers with cement takes into account the water-reducing effect of the superplasticizer and the corresponding relative change in concrete strength. The results demonstrate that the use of the investigated superplasticizer types and low-clinker slag Portland cement allows for achieving a significant increase in concrete strength. The effective contents of various polymer types, which allow the achieving of concrete strengths from 50 MPa to 80 Mpa, has been found.
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Affiliation(s)
- Leonid Dvorkin
- Institute of Civil Engineering and Architecture, National University of Water and Environmental Engineering, 33028 Rivne, Ukraine
| | - Vadim Zhitkovsky
- Institute of Civil Engineering and Architecture, National University of Water and Environmental Engineering, 33028 Rivne, Ukraine
| | - Ruslan Makarenko
- Institute of Civil Engineering and Architecture, National University of Water and Environmental Engineering, 33028 Rivne, Ukraine
| | - Yuri Ribakov
- Department of Civil Engineering, Ariel University, Ariel 40700, Israel
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14
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Son S, Lee W, Jung H, Lee J, Kim C, Lee H, Cho S, Jang J, Lee M, Ryu HC. Experimental Analysis of Various Blockage Performance for LiDAR Sensor Cleaning Evaluation. Sensors (Basel) 2023; 23:2752. [PMID: 36904952 PMCID: PMC10007043 DOI: 10.3390/s23052752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 02/25/2023] [Accepted: 02/28/2023] [Indexed: 06/18/2023]
Abstract
Autonomous driving includes recognition, judgment, and control technologies, and is implemented using sensors such as cameras, LiDAR, and radar. However, recognition sensors are exposed to the outside environment and their performance may deteriorate because of the presence of substances that interfere with vision, such as dust, bird droppings, and insects, during operation. Research on sensor cleaning technology to solve this performance degradation has been limited. This study used various types and concentrations of blockage and dryness to demonstrate approaches to the evaluation of cleaning rates for selected conditions that afford satisfactory results. To determine the effectiveness of washing, the study used the following criteria: washer, 0.5 bar/s and air, 2 bar/s, with 3.5 g being used three times to test the LiDAR window. The study found that blockage, concentration, and dryness are the most important factors, and in that order. Additionally, the study compared new forms of blockage, such as those caused by dust, bird droppings, and insects, with standard dust that was used as a control to evaluate the performance of the new blockage types. The results of this study can be used to conduct various sensor cleaning tests and ensure their reliability and economic feasibility.
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Affiliation(s)
- SungHo Son
- Department of Future Vehicle Research, Korea Automobile Testing and Research Institute, Hwaseong 18247, Republic of Korea
- Department of Convergence Science, University of Sahmyook, Seoul 01795, Republic of Korea
| | - WoongSu Lee
- Department of Future Vehicle Research, Korea Automobile Testing and Research Institute, Hwaseong 18247, Republic of Korea
| | - HyunGi Jung
- Department of Future Vehicle Research, Korea Automobile Testing and Research Institute, Hwaseong 18247, Republic of Korea
| | - JungKi Lee
- Department of Future Vehicle Research, Korea Automobile Testing and Research Institute, Hwaseong 18247, Republic of Korea
| | - ChaRyung Kim
- Department of Future Vehicle Research, Korea Automobile Testing and Research Institute, Hwaseong 18247, Republic of Korea
| | - HyunWoo Lee
- Department of Future Vehicle Research, Korea Automobile Testing and Research Institute, Hwaseong 18247, Republic of Korea
| | - SeoungWoo Cho
- Department of Future Vehicle Research, Korea Automobile Testing and Research Institute, Hwaseong 18247, Republic of Korea
| | - JeongAh Jang
- TOD Based Transportation Research Center, University of Ajou, Suwon 16499, Republic of Korea
| | - Michael Lee
- Department of Business Intelligence and Analytics, Legacy.com, 230 W Monroe Ste 400, Chicago, IL 60606, USA
| | - Han-Cheol Ryu
- Department of Convergence Science, University of Sahmyook, Seoul 01795, Republic of Korea
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15
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Pott U, Crasselt C, Fobbe N, Haist M, Heinemann M, Hellmann S, Ivanov D, Jakob C, Jansen D, Lei L, Li R, Link J, Lowke D, Mechtcherine V, Neubauer J, Nicia D, Plank J, Reißig S, Schäfer T, Schilde C, Schmidt W, Schröfl C, Sowoidnich T, Strybny B, Ukrainczyk N, Wolf J, Xiao P, Stephan D. Characterization data of reference materials used for phase II of the priority program DFG SPP 2005 "Opus Fluidum Futurum - Rheology of reactive, multiscale, multiphase construction materials". Data Brief 2023; 47:108902. [PMID: 36747980 PMCID: PMC9898608 DOI: 10.1016/j.dib.2023.108902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 01/08/2023] [Accepted: 01/09/2023] [Indexed: 01/15/2023] Open
Abstract
A thorough characterization of base materials is the prerequisite for further research. In this paper, the characterization data of the reference materials (CEM I 42.5 R, limestone powder, calcined clay and a mixture of these three components) used in the second funding phase of the priority program 2005 of the German Research Foundation (DFG SPP 2005) are presented under the aspects of chemical and mineralogical composition as well as physical and chemical properties. The data were collected based on tests performed by up to eleven research groups involved in this cooperative program.
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Affiliation(s)
- U. Pott
- Department of Civil Engineering, Technische Universität Berlin, Berlin 13355, Germany
| | - C. Crasselt
- Bundesanstalt für Materialforschung und -prüfung, Berlin 12205, Germany
| | - N. Fobbe
- GeoZentrum Nordbayern, Mineralogy, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen 91054, Germany
| | - M. Haist
- Institute of Building Materials Science, Leibniz Universität Hannover, Hannover 30167, Germany
| | - M. Heinemann
- F. A. Finger-Institute for Building Material Science, Bauhaus-Universität Weimar, Weimar 99423, Germany
| | - S. Hellmann
- Institute of Geosciences, Applied Geology, Friedrich-Schiller-Universität Jena, Jena 07749, Germany
| | - D. Ivanov
- Institute for Particle Technology (iPAT), Technische Universität Braunschweig, Braunschweig 38106, Germany
| | - C. Jakob
- GeoZentrum Nordbayern, Mineralogy, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen 91054, Germany
| | - D. Jansen
- GeoZentrum Nordbayern, Mineralogy, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen 91054, Germany
| | - L. Lei
- Department of Chemistry, Technische Universität München, Garching 85748, Germany
| | - R. Li
- Department of Chemistry, Technische Universität München, Garching 85748, Germany
| | - J. Link
- Institute of Building Materials Science, Leibniz Universität Hannover, Hannover 30167, Germany
| | - D. Lowke
- Institute of Building Materials, Concrete Construction and Fire Safety (iBMB), Technische Universität Braunschweig, Braunschweig 38106, Germany
| | - V. Mechtcherine
- Institute of Construction Materials, Technische Universität Dresden, Dresden 01062, Germany
| | - J. Neubauer
- GeoZentrum Nordbayern, Mineralogy, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen 91054, Germany
| | - D. Nicia
- Institute of Building Materials, Concrete Construction and Fire Safety (iBMB), Technische Universität Braunschweig, Braunschweig 38106, Germany
| | - J. Plank
- Department of Chemistry, Technische Universität München, Garching 85748, Germany
| | - S. Reißig
- Institute of Construction Materials, Technische Universität Dresden, Dresden 01062, Germany
| | - T. Schäfer
- Institute of Geosciences, Applied Geology, Friedrich-Schiller-Universität Jena, Jena 07749, Germany
| | - C. Schilde
- Institute for Particle Technology (iPAT), Technische Universität Braunschweig, Braunschweig 38106, Germany
| | - W. Schmidt
- Bundesanstalt für Materialforschung und -prüfung, Berlin 12205, Germany
| | - C. Schröfl
- Institute of Construction Materials, Technische Universität Dresden, Dresden 01062, Germany
| | - T. Sowoidnich
- F. A. Finger-Institute for Building Material Science, Bauhaus-Universität Weimar, Weimar 99423, Germany
| | - B. Strybny
- Institute of Building Materials Science, Leibniz Universität Hannover, Hannover 30167, Germany
| | - N. Ukrainczyk
- Construction and Building Materials, Technische Universität Darmstadt, Darmstadt 64287, Germany
| | - J. Wolf
- GeoZentrum Nordbayern, Mineralogy, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen 91054, Germany
| | - P. Xiao
- Construction and Building Materials, Technische Universität Darmstadt, Darmstadt 64287, Germany
| | - D. Stephan
- Department of Civil Engineering, Technische Universität Berlin, Berlin 13355, Germany,Corresponding author.
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16
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Su Z, Yan Z, Nakashima K, Takano C, Kawasaki S. Naturally Derived Cements Learned from the Wisdom of Ancestors: A Literature Review Based on the Experiences of Ancient China, India and Rome. Materials (Basel) 2023; 16:603. [PMID: 36676340 PMCID: PMC9867412 DOI: 10.3390/ma16020603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 01/04/2023] [Accepted: 01/05/2023] [Indexed: 06/17/2023]
Abstract
For over a thousand years, many ancient cements have remained durable despite long-term exposure to atmospheric or humid agents. This review paper summarizes technologies of worldwide ancient architectures which have shown remarkable durability that has preserved them over thousands of years of constant erosion. We aim to identify the influence of organic and inorganic additions in altering cement properties and take these lost and forgotten technologies to the production frontline. The types of additions were usually decided based on the local environment and purpose of the structure. The ancient Romans built magnificent structures by making hydraulic cement using volcanic ash. The ancient Chinese introduced sticky rice and other local materials to improve the properties of pure lime cement. A variety of organic and inorganic additions used in traditional lime cement not only changes its properties but also improves its durability for centuries. The benefits they bring to cement may also be useful in enzyme-induced carbonate precipitation (EICP) and microbially induced carbonate precipitation (MICP) fields. For instance, sticky rice has been confirmed to play a crucial role in regulating calcite crystal growth and providing interior hydrophobic conditions, which contribute to improving the strength and durability of EICP- and MICP-treated samples in a sustainable way.
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Affiliation(s)
- Zhan Su
- Division of Sustainable Resources Engineering, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan
| | - Zhen Yan
- Division of Sustainable Resources Engineering, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan
| | - Kazunori Nakashima
- Division of Sustainable Resources Engineering, Faculty of Engineering, Hokkaido University, Sapporo 060-8628, Japan
| | - Chikara Takano
- Division of Sustainable Resources Engineering, Faculty of Engineering, Hokkaido University, Sapporo 060-8628, Japan
| | - Satoru Kawasaki
- Division of Sustainable Resources Engineering, Faculty of Engineering, Hokkaido University, Sapporo 060-8628, Japan
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17
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Tahwia AM, Fouda RM, Abd Elrahman M, Youssf O. Long-Term Performance of Concrete Made with Different Types of Cement under Severe Sulfate Exposure. Materials (Basel) 2022; 16:240. [PMID: 36614579 PMCID: PMC9822289 DOI: 10.3390/ma16010240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 12/22/2022] [Accepted: 12/23/2022] [Indexed: 06/17/2023]
Abstract
Concrete sulfate attack is of great interest as it represents one of the main reasons of concrete deterioration and poor durability for concrete structures. In this research, the effect of different cement types on concrete sulfate resistance was investigated. This included three concrete classes, namely, low strength concrete, medium strength concrete, and high strength concrete. Blast furnace cement (BFC), sulfate resisting Portland cement (CEM I-SR5), and ordinary Portland cement (OPC) were used in a total of eighteen concrete mixes. Three binder contents of 250 kg/m3, 350 kg/m3, and 450 kg/m3 and a constant silica fume (SF) content were applied in this experimental study. The water/binder (w/b) ratio was varied between 0.4 and 0.8. Concrete specimens were immersed in highly severe effective sodium sulfate solutions (10,000 ppm) for 180 days after standard curing for 28 days. The fresh concrete performance was evaluated through a slump test to attain proper workability. Concrete compressive strength and mass change at 28 days and 180 days were measured before and after immersion in the solution to evaluate the long-term effect of sulfate attack on the proposed concrete durability. Scanning electron microscopy (SEM) analysis was conducted to study the concrete microstructure and its deterioration stages. The obtained results revealed that BFC cement has the best resistance to aggressive sulfate attacks. The strength deterioration of BFC cement was 3.5% with w/b of 0.4 and it increased to about 7.8% when increasing the w/b ratio to 0.6, which are comparable to other types of cement used. The findings of this research confirmed that the quality of concrete, specifically its composition of low permeability, is the best and recommended protection against sulfate attack.
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18
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Dvorkin L, Konkol J, Marchuk V, Huts A. Effectiveness of Polymer Additives in Concrete for 3D Concrete Printing Using Fly Ash. Polymers (Basel) 2022; 14:polym14245467. [PMID: 36559834 PMCID: PMC9785001 DOI: 10.3390/polym14245467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Revised: 11/21/2022] [Accepted: 12/11/2022] [Indexed: 12/23/2022] Open
Abstract
The article shows the effectiveness of the use of polymer additives for the production of fine-grained concrete mixtures and concretes based on using coal fly ash, which can be used as working mixtures for a 3D printer. Using mathematical planning of experiments, a set of experimental-statistical models was obtained that describes the influence of mixture composition factors including copolymer additive on the most important properties of ash-containing concrete mixtures and concretes for 3D concrete printing in the presence of a hardening accelerator additive. It is shown that when the dry mixture is mixed in water, the redispersed polymer powders are converted into an adhesive polymer dispersion, which, when the solution cures, creates "rubber bridges" in its pores and at the border with the base. They have high tensile strength and elastically reinforce the cement stone; in addition, they are also capable of not only significantly increasing the adhesion between the layers of the extruded mixture, but also significantly smoothing out such shortcomings of the cement stone as increased brittleness, low ultimate elongation, and a tendency to cracking.
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Affiliation(s)
- Leonid Dvorkin
- Institute of Civil Engineering and Architecture, National University of Water and Environmental Engineering, 33028 Rivne, Ukraine
| | - Janusz Konkol
- Faculty of Civil and Environmental Engineering and Architecture, Rzeszow University of Technology, 35959 Rzeszow, Poland
| | - Vitaliy Marchuk
- Institute of Civil Engineering and Architecture, National University of Water and Environmental Engineering, 33028 Rivne, Ukraine
| | - Andriy Huts
- Faculty of Civil and Environmental Engineering and Architecture, Rzeszow University of Technology, 35959 Rzeszow, Poland
- Correspondence:
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19
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Bonfil D, Veleva L, Feliu S, Escalante-García JI. Corrosion Activity of Carbon Steel B450C and Stainless Steel SS430 Exposed to Extract Solution of a Supersulfated Cement. Materials (Basel) 2022; 15:8782. [PMID: 36556588 PMCID: PMC9781006 DOI: 10.3390/ma15248782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 12/03/2022] [Accepted: 12/05/2022] [Indexed: 06/17/2023]
Abstract
Carbon steel B450C and low-chromium stainless steel SS430 were exposed for 30 days to supersulfated "SS1" cement extract solution, considered as a "green" alternative for partial replacement of the Portland cement clinker. The initial pH of 12.38 dropped since the first day to 7.84, accompanied by a displacement to more negative values of the free corrosion potential (OCP) of the carbon steel up to ≈-480.74 mV, giving the formation of γ-FeOOH, α-FeOOH and Fe2O3, as suggested by XRD and XPS analysis. In the meantime, the OCP of the SS430 tended towards more positive values (+182.50 mV), although at lower pH, and XPS analysis revealed the presence of Cr(OH)3 and FeO as corrosion products, as well the crystals of CaCO3, NaCl and KCl. On both surfaces, a localized corrosion attack was observed in the vicinity of local cathodes (Cu, Mn-carbides, Cr-nitrides, among others), influenced by the presence of Cl- ions in the "SS1" extract solution, originating from the pumice. Two equivalent circuits were proposed for the quantitative analysis of EIS Nyquist and Bode diagrams, whose data were correlated with the OCP values and pH change in time of the "SS1" extract solution. The thickness of the corrosion layer formed on the SS430 surface was ≈0.8 nm, while that on the B450C layer was ≈0.3 nm.
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Affiliation(s)
- David Bonfil
- Center for Research and Advanced Study (CINVESTAV), Applied Physics Department, Campus Merida, Merida 97310, Yucatán, Mexico
| | - Lucien Veleva
- Center for Research and Advanced Study (CINVESTAV), Applied Physics Department, Campus Merida, Merida 97310, Yucatán, Mexico
| | - Sebastian Feliu
- National Center for Metallurgical Research (CENIM-CSIC), Surface Engineering Corrosion and Durability Department, 8040 Madrid, Spain
| | - José Iván Escalante-García
- Center for Research and Advanced Study (CINVESTAV), Campus Saltillo, Ramos Arizpe 25900, Coahuila, Mexico
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20
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Qi C, Xu X, Chen J, Guo L, Chen Q. Ab initio calculations of CO 2 adsorption on β-C 2S(100) and M3-C 3S(001) surfaces: An exploration of early CO 2 sequestration pathways. Environ Res 2022; 215:114412. [PMID: 36162466 DOI: 10.1016/j.envres.2022.114412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 09/14/2022] [Accepted: 09/19/2022] [Indexed: 06/16/2023]
Abstract
Investigating CO2 sequestration in cement-based materials is significant for achieving carbon neutrality in the cement and concrete industries. The early CO2 sequestration pathways on cement-based materials are fundamental for CO2 sequestration, which is not clear. Towards this, the adsorption behavior of CO2 on β-C2S(100) and M3-C3S(001) was investigated at the atomic level using density functional theory calculations, which were then compared with water adsorption results. The molecular adsorption configurations of CO2 on both β-C2S(100) and M3-C3S(001) were tilted from their initial configurations due to the influence of surface Ca and O atoms. The CO2 adsorption energy on M3-C3S(001) and β-C2S(100) were -0.458 eV and -0.426 eV, respectively, indicating adsorption on M3-C3S(001) was more energetically favorable. After CO2 adsorption, electrons were transferred from the surface to the CO2 molecule. Furthermore, the Ca-O bond orders of β-C2S(100) and M3-C3S(001) after CO2 adsorption were maximally decreased by 2.79% and 6.99%, respectively. A more significant adsorption influence on surfaces was found for H2O, with more negative adsorption energy, more evident electron transfer, and a greater decrease in bond order. The CO2 adsorption on β-C2S(100) and M3-C3S(001) were still spontaneous at 298 K and 1 atm. This study provides important theoretical insights into early CO2 sequestration at the atomic level, which has practical implications for the design of efficient CO2 sequestration technologies.
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Affiliation(s)
- Chongchong Qi
- School of Resources and Safety Engineering, Central South University, Changsha, 410083, China; School of Molecular Science, University of Western Australia, Perth, 6009, Australia.
| | - Xinhang Xu
- School of Resources and Safety Engineering, Central South University, Changsha, 410083, China
| | - Jie Chen
- School of Resources and Safety Engineering, Chongqing University, Chongqing, 400044, China
| | - Li Guo
- School of Resources and Safety Engineering, Central South University, Changsha, 410083, China
| | - Qiusong Chen
- School of Resources and Safety Engineering, Central South University, Changsha, 410083, China.
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21
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Bădănoiu A, Moanță A, Dumitrescu O, Nicoară AI, Trușcă R. Waste Glass Valorization as Raw Material in the Production of Portland Clinker and Cement. Materials (Basel) 2022; 15:7403. [PMID: 36295468 PMCID: PMC9611181 DOI: 10.3390/ma15207403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 10/11/2022] [Accepted: 10/18/2022] [Indexed: 06/16/2023]
Abstract
The paper presents experimental results regarding the synthesis of Portland clinker starting from raw mixes based on two types of clayey precursors, i.e., clay and marl (the most common types of raw materials used in the cement industry), with and without glass waste content. The soda-lime glass waste addition (5.36-5.59 wt %), used to control the silica ratio of the raw mix, improved the raw mix burnability and decreased the calcination temperature (by 20 °C), leading to a decrease in fuel consumption and contributing to the reduction in CO2 emissions associated with clinker and cement production. The clinkers obtained by the calcination of raw mixes with glass waste content at 1430 °C with a 30 min plateau had a similar mineralogical composition and microstructure to the clinkers obtained from the reference raw mixes and fulfilled the requirements of the specific standard EN 197-1. The obtained clinkers were used to produce two types of Portland cement, i.e., a unitary cement (CEM I) and a binary blended cement with slag (CEM II/B-S). The main characteristics of these cements, i.e., loss on ignition, insoluble residue, sulfate and chloride contents, as well as the setting time and soundness, meet the conditions stipulated in the EN 197-1 standard. The values of compressive strength, assessed on mortars after 2, 7 and 28 days of curing, allow the classification of all CEM I cements in the 42.5 R class. In the case of CEM II/B-S cements, those obtained from raw mixes with clay can be classified in the 42.5 N class, while those obtained from raw mixes with marl are classified in the 32.5 R class.
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Affiliation(s)
- Alina Bădănoiu
- Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, 011061 Bucharest, Romania
| | - Adriana Moanță
- CEPROCIM S.A. Preciziei No. 6, 062203 Bucharest, Romania
| | - Ovidiu Dumitrescu
- Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, 011061 Bucharest, Romania
- National Research Center for Micro and Nanomaterials, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, 060042 Bucharest, Romania
| | - Adrian Ionuț Nicoară
- Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, 011061 Bucharest, Romania
- National Research Center for Micro and Nanomaterials, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, 060042 Bucharest, Romania
| | - Roxana Trușcă
- Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, 011061 Bucharest, Romania
- National Research Center for Micro and Nanomaterials, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, 060042 Bucharest, Romania
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Kriptavičius D, Girskas G, Skripkiūnas G. Use of Natural Zeolite and Glass Powder Mixture as Partial Replacement of Portland Cement: The Effect on Hydration, Properties and Porosity. Materials (Basel) 2022; 15:ma15124219. [PMID: 35744278 PMCID: PMC9228779 DOI: 10.3390/ma15124219] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 06/06/2022] [Accepted: 06/09/2022] [Indexed: 02/04/2023]
Abstract
The study investigates effect of the additive consisting of natural zeolite (clinoptilolite) and soda lime glass powder on the hydration, mechanical properties and porosity of Portland cement concrete. The effect of mineral additive on the technological, physical-mechanical properties and porosity of the mortar was investigated by increasing the content of natural zeolite and glass powder added to the mortar up to 20% by weight of cement in increments of 5% and different particles size of natural zeolite. The mixes with the best technological and mechanical properties were identified and further studies were conducted by replacing 10% and 15% of cement with natural zeolite and soda lime glass with an average grain size of 59.3 μm, 29.0 μm or 3.6 μm of zeolite, and 29.6 μm of glass powder. The hydration process and microstructure of hardened cement paste modified with the aforementioned mineral additives was analysed by microcalorimetry, X-ray diffraction tests and thermogravimetric analysis. The optimal composition of cement paste and particle size distribution of natural zeolite were determined to achieve the higher flexural and compressive strength and lower open porosity. The mixture of mineral additives has the highest effect in terms of flexural and compressive strength and open porosity when added at the proportion 75:15:10 (cement:natural zeolite:soda lime glass) and when zeolite with an average particle size of about 3.6 μm is used
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Roma M, Gupta R, Hegde S. A prospective clinical study with one year follow up of deep caries management using a novel biomaterial. BMC Res Notes 2022; 15:150. [PMID: 35484566 DOI: 10.1186/s13104-022-06041-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 04/20/2022] [Indexed: 12/31/2022] Open
Abstract
OBJECTIVES The objectives of this study was to check the outcome of the direct and indirect pulp capping procedure using MTA (Mineral Trioxide Aggregate) by comparing the pre-and post-operative pain by using VAS scale, associating the pre- and post- operative changes in intraoral periapical radiograph and clinical symptoms. MATERIALS AND METHODS In this prospective clinical study 10 cases (5 for direct and 5 for indirect) with deep carious lesions (symptomatic) with no periapical changes were selected for the trial. The participants were subjected to deep caries management procedure under rubber dam where MTA is placed as pulp capping material followed by immediate restoration with sandwich technique using composite resin. The participants were followed up at recall visits of 1 month, 3 months, 6 months and 1 year intervals for clinical and radiographic evaluation. RESULTS The results of the study, analyzing the VAS, clinical symptoms and radiographic changes did not show any signs of pain, clinical and radiographic symptoms at 1 month, 3 months, 6 months and 1 year intervals. CONCLUSIONS It was concluded that MTA can be used for deep caries management as a pulp capping material which being equivalent to calcium hydroxide.
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Kim H, Son HM. Effects of Air Entrainment on Bacterial Viability in Cement Paste. Materials (Basel) 2022; 15:ma15062163. [PMID: 35329614 PMCID: PMC8948680 DOI: 10.3390/ma15062163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Revised: 03/06/2022] [Accepted: 03/09/2022] [Indexed: 12/10/2022]
Abstract
This study investigated the effect of air entrainment (AE) on bacterial viability in cementitious materials. Specimens were fabricated with Portland cement, urea, calcium lactate, and ureolytic bacteria, and with varying amounts of an AE agent. Specimens with different amounts of the AE agent were fabricated, and then a compressive strength test, quantitative polymerase chain reaction, X-ray diffraction, and thermogravimetry were used to investigate the mechanical properties, viability of bacteria, and hydrates of the specimens. The highest compressive strength was achieved by the specimen with 0.3% AE agent, while the compressive strength of the specimens decreased considerably when the incorporated AE agent was over 0.6%, due to increased porosity. The quantitative polymerase chain reaction result showed that the cell number of the viable bacteria was increased by incorporation of the AE agent, which also corresponded with an increase in CaCO3 due to microbial mineral formation. The obtained result confirmed the positive effect of AE agent incorporation in cementitious materials containing bacterial admixtures, as the viability of bacteria, which play a vital role in self-healing efficiency of concrete, was increased by the space provided by the AE agent in the cement matrix. In addition, the quantity of CaCO3 and the compressive strength were highest when 0.3% AE agent was incorporated.
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Affiliation(s)
| | - H. M. Son
- Correspondence: ; Tel.: +82-10-5196-4169
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Miron GD, Kulik DA, Lothenbach B. Porewater compositions of Portland cement with and without silica fume calculated using the fine-tuned CASH+NK solid solution model. Mater Struct 2022; 55:212. [PMID: 36172008 PMCID: PMC9509308 DOI: 10.1617/s11527-022-02045-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Accepted: 09/07/2022] [Indexed: 05/03/2023]
Abstract
UNLABELLED The CASH+ sublattice solid solution model of C-S-H aims to predict the composition of C-S-H and its ability to take up alkalis. It was originally developed for dilute systems with high water-solid ratios, and thus in this paper further optimized and benchmarked against measured pore solution compositions of hydrated Portland cement (PC) and PC blended with silica fume (SF) at realistic water-binder ratios. To get an improved agreement with the pore solution data, the stability of two CASH+ model endmembers, TCKh and TCNh, has been fine-tuned with standard Gibbs energy corrections of + 7.0 and + 5.0 kJ·mol-1, respectively (at 1 bar, 25 °C). The agreement was maintained with the experiments used to originally parameterize the CASH+ model for the uptake of K and Na in dilute systems. The K and Na concentrations predicted using the fine-tuned CASH+NK model are in a good agreement with the measured values for PC and PC + SF system at different water to binder ratios, silica fume additions, and at temperatures up to 80 °C. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1617/s11527-022-02045-0.
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Affiliation(s)
- George Dan Miron
- Laboratory for Waste Management LES, Paul Scherrer Institut, 5232 Villigen, Switzerland
| | - Dmitrii A. Kulik
- Laboratory for Waste Management LES, Paul Scherrer Institut, 5232 Villigen, Switzerland
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Campanhão AF, Marvila MT, de Azevedo ARG, da Silva TR, Fediuk R, Vatin N. Recycled PET Sand for Cementitious Mortar. Materials (Basel) 2021; 15:ma15010273. [PMID: 35009419 PMCID: PMC8745950 DOI: 10.3390/ma15010273] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 12/22/2021] [Accepted: 12/25/2021] [Indexed: 11/16/2022]
Abstract
Cementitious materials cause a great impact on the environment due to the calcination of clinker and the extraction of non-renewable mineral resources. In this work, the replacement of quartz sand from the river by PET sand was evaluated at levels of 10%, 20%, and 30%. Tests were performed in the fresh state through consistency, air retention, density, and incorporated air and in the hardened state for compressive strength, flexural strength, density, capillarity, and water absorption. The results show that PET sand is viable in contents of up to 10%, improving the mechanical properties of the mortar and without compromising its workability and incorporated air properties. Above that level, the loss of properties is very excessive, mainly of workability and incorporated air. The incorporated air of the 30% composition, for example, reaches 24%, an excessive value that impacts the properties of the hardened state, making it impossible to use the material at levels greater than 20%. It is concluded that the use of recycled PET sand is a possibility that contributes to sustainable development, as it reduces the extraction of quartz sand from the river, a non-renewable mineral resource.
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Affiliation(s)
- Angélica Faria Campanhão
- LAMAV-Advanced Materials Laboratory, State University of the Northern Rio de Janeiro, Av. Alberto Lamego, 2000, Campos dos Goytacazes 28013-602, Brazil; (A.F.C.); (A.R.G.d.A.); (T.R.d.S.)
| | - Markssuel Teixeira Marvila
- LAMAV-Advanced Materials Laboratory, State University of the Northern Rio de Janeiro, Av. Alberto Lamego, 2000, Campos dos Goytacazes 28013-602, Brazil; (A.F.C.); (A.R.G.d.A.); (T.R.d.S.)
- CRP–Rio Paranaíba Campus, UFV-Federal University of Viçosa, Rodovia BR 230 KM 7, Rio Paranaiba 38810-000, Brazil
- Correspondence: (M.T.M.); (R.F.)
| | - Afonso R. G. de Azevedo
- LAMAV-Advanced Materials Laboratory, State University of the Northern Rio de Janeiro, Av. Alberto Lamego, 2000, Campos dos Goytacazes 28013-602, Brazil; (A.F.C.); (A.R.G.d.A.); (T.R.d.S.)
- LECIV-Civil Engineering Laboratory, State University of the Northern Rio de Janeiro, Av. Alberto Lamego, 2000, Campos dos Goytacazes 28013-602, Brazil
| | - Tulane Rodrigues da Silva
- LAMAV-Advanced Materials Laboratory, State University of the Northern Rio de Janeiro, Av. Alberto Lamego, 2000, Campos dos Goytacazes 28013-602, Brazil; (A.F.C.); (A.R.G.d.A.); (T.R.d.S.)
| | - Roman Fediuk
- Polytechnic Institute, Far Eastern Federal University, 690922 Vladivostok, Russia
- Correspondence: (M.T.M.); (R.F.)
| | - Nikolai Vatin
- Peter the Great St. Petersburg Polytechnic University, 195251 St. Petersburg, Russia;
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Gołaszewska M, Klemczak B, Gołaszewski J. Thermal Properties of Calcium Sulphoaluminate Cement as an Alternative to Ordinary Portland Cement. Materials (Basel) 2021; 14:ma14227011. [PMID: 34832410 PMCID: PMC8622666 DOI: 10.3390/ma14227011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 11/10/2021] [Accepted: 11/17/2021] [Indexed: 11/16/2022]
Abstract
This paper presents the results of research into the heat of hydration and activation energy of calcium sulphoaluminate (CSA) cement in terms of the dependence on curing temperature and water/cement ratio. Cement pastes with water/cement ratios in the range of 0.3-0.6 were tested by isothermal calorimetry at 20 °C, 35 °C and 50 °C, with the evolved hydration heat and its rate monitored for 168 h from mixing water with cement. Reference pastes with ordinary Portland cement (OPC) were also tested in the same range. The apparent activation energy of CSA and OPC was determined based on the results of the measurements. CSA pastes exhibited complex thermal behaviour that differed significantly from the thermal behaviour of ordinary Portland cement. The results show that both the w/c ratio and elevated temperature have a meaningful effect on the heat emission and the hydration process of CSA cement pastes. The determined apparent activation energy of CSA revealed its substantial variability and dependence, both on the w/c ratio and the curing temperature.
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Yang Z, Ye H, Yuan Q, Li B, Li Y, Zhou D. Factors Influencing the Hydration, Dimensional Stability, and Strength Development of the OPC-CSA-Anhydrite Ternary System. Materials (Basel) 2021; 14:ma14227001. [PMID: 34832399 PMCID: PMC8622901 DOI: 10.3390/ma14227001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 11/04/2021] [Accepted: 11/10/2021] [Indexed: 11/16/2022]
Abstract
Due to the advantages of high early strength and rapid setting, ternary systems consisting of ordinary Portland clinker (OPC), calcium sulphoaluminate (CSA) clinker, and anhydrite have broad application prospects. However, further studies need to be undertaken to find a more optimal mixing proportion of this ternary binder in order to meet basic performance requirements. In this paper, isothermal calorimetric tests, chemical shrinkage tests, drying shrinkage tests, and compressive strength tests were carried out to systematically identify the effect of the OPC/CSA ratio and anhydrite dosage on the hydration, mechanical property development, and dimensional stability of ternary binders. It was found that a higher CSA content leads to a higher cumulative hydration heat, a shorter acceleration period, and a delayed induction period, which can be ascribed to the retardation of C3S at a high aluminate concentration. However, a higher addition of anhydrite can retard the main peak of hydration despite promoting the intermediate peak and improving the hydration reaction rate. The drying shrinkage of blends decreases first along with the CSA proportion and then increases. Moreover, a higher anhydrite content mitigates the drying shrinkage and hinders the strength development. Finally, considering the properties of both the fresh and hardened binder, the ternary blends with 5% anhydrite and OPC/CSA ratios ranging from 3/7 to 2/8 were identified as most suitable for applications that require a high early strength, stable late strength, and small level of shrinkage.
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Affiliation(s)
- Zhenzhen Yang
- School of Civil Engineering, Central South University, Changsha 410075, China;
- National Engineering Laboratory for High Speed Railway Construction, Changsha 410075, China
| | - Hansong Ye
- Zhejiang Communications Investment Group Co. Ltd., Hangzhou 310020, China;
| | - Qiang Yuan
- School of Civil Engineering, Central South University, Changsha 410075, China;
- National Engineering Laboratory for High Speed Railway Construction, Changsha 410075, China
- Correspondence:
| | - Baiyun Li
- Foshan Transportation Science and Technology Co. Ltd., Foshan 528000, China;
| | - Yuelin Li
- Department of Civil Engineering, KU Leuven, Campus Bruges, 8200 Bruges, Belgium;
| | - Dajun Zhou
- ZhongNan Engineering Co. Ltd., Changsha 410075, China;
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Jebbawy M, Thiery V, Bouichou M, Marie-Victoire E, Davy C, Izoret L, Albert-Mercier C, Moreau M. First historical cements in France from Boulogne sur Mer: Investigations on 19th century's manufactured cement-based monuments. J Microsc 2021; 286:63-68. [PMID: 34687229 DOI: 10.1111/jmi.13071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 09/27/2021] [Accepted: 10/20/2021] [Indexed: 11/30/2022]
Abstract
The Boulogne-Sur-Mer area in the North of France is one of the cradles of the French cement industry (the other main one is Grenoble region due to Joseph Vicat's first cement works). From fast setting (Roman) to Portland, those cements were famous in France and have been used throughout the entire country. The main objective of this study is to give a preliminary insight of the type of binders used since there is currently few and scattered data on those specific structures and to assess the efficiency of traditional analytical techniques [X-ray diffraction (XRD), optical (OM) and scanning electron microscopy (SEM) observations, coupled with EDS analysis] used to differentiate natural and artificial cements.
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Affiliation(s)
| | | | | | | | | | - Laurent Izoret
- SFIC, Syndicat Français de l'Industrie Cimentière, Paris-La-Défense Cedex
| | | | - Myriam Moreau
- Univ. Lille, CNRS, UMR 8516 - LASIR, Laboratoire Avancé de Spectroscopie pour les Interactions, la Réactivité et l'Environnement, Lille, France
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Subhi H, Husein A, Mohamad D, Nik Abdul Ghani NR, Nurul AA. Chitosan-Based Accelerated Portland Cement Promotes Dentinogenic/Osteogenic Differentiation and Mineralization Activity of SHED. Polymers (Basel) 2021; 13:3358. [PMID: 34641172 DOI: 10.3390/polym13193358] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 09/05/2021] [Accepted: 09/25/2021] [Indexed: 01/26/2023] Open
Abstract
Calcium silicate-based cements (CSCs) are widely used in various endodontic treatments to promote wound healing and hard tissue formation. Chitosan-based accelerated Portland cement (APC-CT) is a promising and affordable material for endodontic use. This study investigated the effect of APC-CT on apoptosis, cell attachment, dentinogenic/osteogenic differentiation and mineralization activity of stem cells from human exfoliated deciduous teeth (SHED). APC-CT was prepared with various concentrations of chitosan (CT) solution (0%, 0.625%, 1.25% and 2.5% (w/v)). Cell attachment was determined by direct contact analysis using field emission scanning electron microscopy (FESEM); while the material extracts were used for the analyses of apoptosis by flow cytometry, dentinogenic/osteogenic marker expression by real-time PCR and mineralization activity by Alizarin Red and Von Kossa staining. The cells effectively attached to the surfaces of APC and APC-CT, acquiring flattened elongated and rounded-shape morphology. Treatment of SHED with APC and APC-CT extracts showed no apoptotic effect. APC-CT induced upregulation of DSPP, MEPE, DMP-1, OPN, OCN, OPG and RANKL expression levels in SHED after 14 days, whereas RUNX2, ALP and COL1A1 expression levels were downregulated. Mineralization assays showed a progressive increase in the formation of calcium deposits in cells with material containing higher CT concentration and with incubation time. In conclusion, APC-CT is nontoxic and promotes dentinogenic/osteogenic differentiation and mineralization activity of SHED, indicating its regenerative potential as a promising substitute for the commercially available CSCs to induce dentin/bone regeneration.
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James J, Arthi C, Balaji G, Chandraleka N, Naveen Kumar RHM. Lime activated flyash-phosphogypsum blend as a low-cost alternative binder. Int J Environ Sci Technol (Tehran) 2021; 19:8969-8978. [PMID: 34484366 PMCID: PMC8404028 DOI: 10.1007/s13762-021-03618-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 07/21/2021] [Accepted: 08/15/2021] [Indexed: 06/13/2023]
Abstract
This study investigates the potential of a blended binder formulated from two industrial solid wastes viz. phosphogypsum and fly ash in combination with lime. Three mix proportions of phosphogypsum and fly ash were investigated, and the minimum lime contents required for activation were determined using the Eades and Grim pH test. The lime-fly ash-phosphogypsum blends were then cast into cubes, both in their paste form as well as mortar form, mixed with sand in the ratio of 1:3. They were cured for a period of seven days, and afterwards, their compressive strength was determined. Ordinary Portland cement and lime mortar blocks were also cast as control specimens for comparative evaluation of the strength. The optimal lime-fly ash-phosphogypsum blend was identified and used to construct a masonry prism, and the strengths of the masonry prisms were also evaluated. The optimal lime-fly ash-phosphogypsum blend mortar was also subjected to an X-ray diffraction analysis to determine the reaction products formed during hydration. The study revealed that 5% lime mixed with fly ash:phosphogypsum in the ratio of 3:1 was the optimal proportion which gave the maximum strength to the cubes. The optimal lime-fly ash-phosphogypsum blend mortar developed strength that was higher than conventional Portland cement and lime mortar. The optimal lime-fly ash-phosphogypsum blend mortar masonry prisms developed strength that was comparable to that of Portland cement mortar masonry. The X-ray diffraction analysis revealed the formation of calcium silicate hydrate minerals as well as ettringite and portlandite which were responsible for strength gain.
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Affiliation(s)
- J. James
- Sri Sivasubramaniya Nadar College of Engineering, Kalavakkam, Chennai, 603110 India
| | - C. Arthi
- Tagore Engineering College, Rathinamangalam, Chennai, 600127 India
| | - G. Balaji
- Tagore Engineering College, Rathinamangalam, Chennai, 600127 India
| | - N. Chandraleka
- Tagore Engineering College, Rathinamangalam, Chennai, 600127 India
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Kozai N, Sato J, Osugi T, Shimoyama I, Sekine Y, Sakamoto F, Ohnuki T. Sewage sludge ash contaminated with radiocesium: Solidification with alkaline-reacted metakaolinite (geopolymer) and Portland cement. J Hazard Mater 2021; 416:125965. [PMID: 34492877 DOI: 10.1016/j.jhazmat.2021.125965] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 04/20/2021] [Accepted: 04/20/2021] [Indexed: 06/13/2023]
Abstract
This study contributes toward developing measures for the disposal of radiocesium-contaminated sewage sludge ash (SSA). Here, we prepared two types of solidified bodies containing 30 wt% radiocesium-bearing SSA. The material used for the two solidified bodies were alkaline-reacted metakaolinite (geopolymer) and ordinary Portland cement (OPC). Cement has been used for solidification of low-level radioactive wastes, and geopolymer is a candidate of cement alternative materials. The characteristics of these solidified bodies were investigated by various aspects including mechanical strength, transformation of SSA components during solidification, and radiocesium confinement ability by leaching test. The compressive strength of geopolymer- and OPC-solidified bodies at 30 wt% SSA content was more than 40 MPa. After static leaching test at 60 °C, 137Cs was hardly leached out from the geopolymer-solidified bodies containing SSA at 30 wt% to ultrapure water (<0.1%), whereas more than 30% 137Cs was leached from the OPC-solidified bodies containing SSA at 30 wt% even though only ~9% of 137Cs in the SSA is soluble. These results strongly indicate that geopolymer is far superior to OPC for solidifying radiocesium-bearing SSA.
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Affiliation(s)
- Naofumi Kozai
- Advanced Science Research Center, Japan Atomic Energy Agency (JAEA), Tokai, Ibaraki 319-1195, Japan.
| | - Junya Sato
- Nuclear Backend Technology Center, JAEA, Tokai, Ibaraki 319-1194, Japan
| | - Takeshi Osugi
- Nuclear Backend Technology Center, JAEA, Tokai, Ibaraki 319-1194, Japan
| | - Iwao Shimoyama
- Advanced Science Research Center, Japan Atomic Energy Agency (JAEA), Tokai, Ibaraki 319-1195, Japan
| | - Yurina Sekine
- Advanced Science Research Center, Japan Atomic Energy Agency (JAEA), Tokai, Ibaraki 319-1195, Japan; Materials Sciences Research Center, JAEA, Tokai, Ibaraki 319-1195, Japan
| | - Fuminori Sakamoto
- Advanced Science Research Center, Japan Atomic Energy Agency (JAEA), Tokai, Ibaraki 319-1195, Japan
| | - Toshihiko Ohnuki
- Advanced Science Research Center, Japan Atomic Energy Agency (JAEA), Tokai, Ibaraki 319-1195, Japan; Laboratory for Advanced Nuclear Energy, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
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Lehner P, Gołaszewski J. Relationship of Different Properties from Non-Destructive Testing of Heavy Concrete from Magnetite and Serpentinite. Materials (Basel) 2021; 14:ma14154288. [PMID: 34361479 PMCID: PMC8348025 DOI: 10.3390/ma14154288] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Revised: 07/24/2021] [Accepted: 07/30/2021] [Indexed: 11/16/2022]
Abstract
Radiation-shielding concrete has been analyzed by several methods of destructive and non-destructive testing (NDT). Concretes made of crushed basalt, magnetite, serpentinite, and two different types of cement (Portland cement CEM I and slag cement CEM III/A) were studied. In this study, we analyzed concrete columns with a height of 1200 mm and a cross-section of 200 × 200 mm2. The top and bottom of the column were analyzed using data from compressive strength, dynamic modulus of elasticity, water penetration, and diffusion coefficients derived from the electrical resistivity test. This article presents the properties of fresh concrete and concrete after two years of setting. It was determined how the different ratios of basalt, magnetite, and serpentinite affect the individual measured parameters. Furthermore, correlation relations between individual resulting values were analyzed. It was observed that compressive strength generally does not correlate with other results. The diffusion coefficient correlated well with density and water penetration. Little or no correlation was observed in the diffusion coefficient with compressive strength and modulus of elasticity. The results of the study make it possible to refine the testing of heavy concretes in terms of electrical resistivity, and point to the possible use of NDT methods. The results also show which composition of heavy concrete is better in terms of effective diffusivity.
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Affiliation(s)
- Petr Lehner
- Department of Structural Mechanics, Faculty of Civil Engineering, VSB-Technical University of Ostrava, Ludvíka Podéště 1875/17, 708 33 Ostrava-Poruba, Czech Republic
- Correspondence:
| | - Jacek Gołaszewski
- Department of Building Processes and Building Physics, Faculty of Civil Engineering, Silesian University of Technology, Akademicka Street 5, 44-100 Gliwice, Poland;
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Krug R, Ortmann C, Reich S, Hahn B, Krastl G, Soliman S. Tooth discoloration induced by apical plugs with hydraulic calcium silicate-based cements in teeth with open apices-a 2-year in vitro study. Clin Oral Investig 2021; 26:375-383. [PMID: 34151389 PMCID: PMC8791895 DOI: 10.1007/s00784-021-04009-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 05/20/2021] [Indexed: 11/10/2022]
Abstract
Objectives To assess tooth discoloration induced by different hydraulic calcium silicate-based cements (HCSCs), including effects of blood and placement method. Materials and methods Eighty bovine teeth cut to a length of 18 mm (crown 8 mm, root 10 mm) were randomly assigned to 10 groups (n = 8), receiving orthograde apical plug treatment (APT). Apical plugs were 4 mm in length and made of ProRoot MTA (Dentsply), Medcem MTA (Medcem), TotalFill BC RRM Fast Set Putty (Brasseler), or Medcem Medical Portland Cement (Medcem) plus bismuth oxide (Bi2O3) with and without bovine blood. Further, orthograde (with or without preoperative adhesive coronal dentin sealing) and retrograde APT were compared. Teeth were obturated with gutta-percha and sealer, sealed with composite and stored in distilled water. Tooth color was measured on apical plug, gutta-percha/sealer, and crown surface before treatment versus 24 h, 1, 3, 6, 12, and 24 months after treatment by spectrophotometry. Color difference (ΔE) values were calculated and analyzed by Shapiro–Wilk test, ANOVA with post hoc tests, Friedman test, t test, and post hoc tests with Bonferroni correction (α = .05). Results Tooth discoloration occurred in all groups with no significant differences between HCSCs (p > .05). After 24 months, color changes were prominent on roots but insignificant on crowns. Blood contamination induced a significantly decreased luminescence (p < .05). Blood had a stronger impact on tooth color than Bi2O3. No relevant effects of retrograde placement (p > .05) or preoperative dentin sealing (p > .05) were detected. Conclusions Apical plugs of the tested HCSCs cause discoloration of bovine roots, but not discoloration of bovine tooth crowns within a 24-month period. Clinical relevance APT should be performed carefully while avoiding direct contact with the coronal dentin, and in that case no aesthetic impairments occur.
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Affiliation(s)
- Ralf Krug
- Department of Conservative Dentistry and Periodontology and Center of Dental Traumatology, University Hospital of Würzburg, Pleicherwall 2, 97070, Würzburg, Germany.
| | | | | | - B Hahn
- Department of Conservative Dentistry and Periodontology and Center of Dental Traumatology, University Hospital of Würzburg, Pleicherwall 2, 97070, Würzburg, Germany
| | - G Krastl
- Department of Conservative Dentistry and Periodontology and Center of Dental Traumatology, University Hospital of Würzburg, Pleicherwall 2, 97070, Würzburg, Germany
| | - S Soliman
- Department of Conservative Dentistry and Periodontology and Center of Dental Traumatology, University Hospital of Würzburg, Pleicherwall 2, 97070, Würzburg, Germany
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Kuziak J, Zalegowski K, Jackiewicz-Rek W, Stanisławek E. Influence of the Type of Cement on the Action of the Admixture Containing Aluminum Powder. Materials (Basel) 2021; 14:ma14112927. [PMID: 34072285 PMCID: PMC8199390 DOI: 10.3390/ma14112927] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 05/19/2021] [Accepted: 05/26/2021] [Indexed: 11/16/2022]
Abstract
The study of the effect of cement type on the action of an admixture increasing the volume of concrete (containing aluminum powder), used in amounts of 0.5-1.5% of cement mass, was presented. The tests were carried out on cement mortars with Portland (CEM I) and ground granulated blast-furnace slag cement (CEM III). The following tests were carried out for the tested mortars: the air content in fresh mortars, compressive strength, flexural strength, increase in mortar volume, bulk density, pore structure evaluation (by the computer image analysis method) and changes in the concentration of OH- ions during the hydration of used cements. Differences in the action of the tested admixture depending on the cement used were found. To induce the expansion of CEM III mortars, a smaller amount of admixture is required than in the case of CEM I cement. Using the admixture in amounts above 1% of the cement mass causes cracks of mortars with CEM III cement due to slow hydrogen evolution, which occurs after mortar plasticity is lost. The use of an aluminum-containing admixture reduces the strength properties of the cement mortars, the effect being stronger in the case of CEM III cement. The influence of the sample molding time on the admixture action was also found.
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Krystek M, Pakulski D, Górski M, Szojda L, Ciesielski A, Samorì P. Electrochemically Exfoliated Graphene for High-Durability Cement Composites. ACS Appl Mater Interfaces 2021; 13:23000-23010. [PMID: 33944553 DOI: 10.1021/acsami.1c04451] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The development of radically new types of corrosion-resistant cement composites is nowadays compulsory in view of the continuous increase of concrete consumption combined with the intrinsically defective nature of concrete. Among various additives being employed in the concrete technology, carbon nanomaterials have emerged as extremely powerful components capable of remarkably enhancing nano- and microstructures as well as properties of cement-based composites. In this study, we demonstrate that cement mortar incorporating electrochemically exfoliated graphene (EEG) exhibits significantly improved fluid transport properties. The addition of 0.05 wt % of EEG to ordinary Portland cement mortar results in the reduction of initial and secondary sorptivity values by 21 and 25%, respectively. This leads to the outstanding resistance of EEG-cement composites to highly corrosive environments, namely, chloride and sulfate solutions. These observations, combined with the previously reported remarkable enhancement of the tensile strength of EEG-cement mortars, represent a major step toward the development of highly durable graphene-based cement composites.
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Affiliation(s)
- Małgorzata Krystek
- Université de Strasbourg, CNRS, ISIS, 8 alleé Gaspard Monge, 67000 Strasbourg, France
- Department of Structural Engineering, Silesian University of Technology, Akademicka 5, 44-100 Gliwice, Poland
| | - Dawid Pakulski
- Faculty of Chemistry, Adam Mickiewicz University, Umultowska 89b, 61-614 Poznań, Poland
- Centre for Advanced Technologies, Adam Mickiewicz University, Umultowska 89c, 61-614 Poznań, Poland
| | - Marcin Górski
- Department of Structural Engineering, Silesian University of Technology, Akademicka 5, 44-100 Gliwice, Poland
| | - Leszek Szojda
- Department of Structural Engineering, Silesian University of Technology, Akademicka 5, 44-100 Gliwice, Poland
| | - Artur Ciesielski
- Université de Strasbourg, CNRS, ISIS, 8 alleé Gaspard Monge, 67000 Strasbourg, France
- Centre for Advanced Technologies, Adam Mickiewicz University, Umultowska 89c, 61-614 Poznań, Poland
| | - Paolo Samorì
- Université de Strasbourg, CNRS, ISIS, 8 alleé Gaspard Monge, 67000 Strasbourg, France
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Blikharskyy Z, Sobol K, Markiv T, Selejdak J. Properties of Concretes Incorporating Recycling Waste and Corrosion Susceptibility of Reinforcing Steel Bars. Materials (Basel) 2021; 14:2638. [PMID: 34070028 PMCID: PMC8158128 DOI: 10.3390/ma14102638] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 05/13/2021] [Accepted: 05/14/2021] [Indexed: 11/16/2022]
Abstract
In this paper, properties of concretes incorporating recycling waste and corrosion susceptibility of reinforcing steel bars were studied. It was established that fineness of ground granulated blast furnace slag (GGBFS) and fly ash (FA) and their simultaneous combination have an influence on the kinetics of strength development of Portland cements and concretes. The compressive strength of concrete containing 10% by mass of GGBFS and 10% by mass of FA even exceeds the compressive strength of control concrete by 6.5% and concrete containing 20% by mass of GGBFS by 8.8% after 56 days of hardening. The formation of the extra amount of ettringite, calcium hydrosilicates as well as hydroaluminosilicates causes tightening of a cement matrix of concrete, reducing its water absorption, and improving its resistance to freezing and thawing damage.
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Affiliation(s)
- Zinoviy Blikharskyy
- Faculty of Civil Engineering, Czestochowa University of Technology, 69 Str. Dabrowskiego, 42-201 Czestochowa, Poland;
| | - Khrystyna Sobol
- Lviv Polytechnic National University, Bandera Str. 12, 79000 Lviv, Ukraine; (K.S.); (T.M.)
| | - Taras Markiv
- Lviv Polytechnic National University, Bandera Str. 12, 79000 Lviv, Ukraine; (K.S.); (T.M.)
| | - Jacek Selejdak
- Faculty of Civil Engineering, Czestochowa University of Technology, 69 Str. Dabrowskiego, 42-201 Czestochowa, Poland;
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Bayraktar OY. Possibilities of disposing silica fume and waste glass powder, which are environmental wastes, by using as a substitute for Portland cement. Environ Sci Pollut Res Int 2021; 28:16843-16854. [PMID: 33394426 DOI: 10.1007/s11356-020-12195-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 12/21/2020] [Indexed: 06/12/2023]
Abstract
In this study, the possibilities of disposal of environmental waste, silica fume, and waste glass powder as substitutes in the mortar samples in Portland cement were investigated. For this purpose, Portland cement (CEM I), silica fume (SF), waste glass powder (WGP), CEN standard sand, and water were used in mortar production. Additive cements were obtained by using the SF, WGP, and SFWGP substitution methods in Portland cement at the rates of 10, 20, 30, and 40%. The flexural strength, compressive strength, radiation permeability (determination of linear absorption coefficient), high temperature, and alkali-silica reaction (ASR) effect on SF, WGP, and SFWGP were examined and compared with the control PC 42.5R samples. Mortar samples of 40 × 40 × 160 mm size were obtained with the grouts/mortars produced, and the samples were exposed to five temperature effects, namely, 20, 150, 300, 700, and 1000 ° C. Samples kept at 20 ° C are accepted as baseline. A total of 429 samples were studied, including the cooling process in the air (spontaneously in the laboratory, 20 ° C ± 2). After the samples achieved room temperature, flexural and compressive strength tests were carried out at 28 and 90 days. Test results demonstrate that SF, WGP, and SFWGP, which are environmental wastes, can be disposed both as a pozzolanic additive material both alone and together in cement mortars, can be utilized in buildings with high fire hazard, and the sample with the highest linear absorption coefficient is the sample obtained with SFWGP, and also, the expansion values that occur in SF and WGP are less than the control sample.
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Affiliation(s)
- Oguzhan Yavuz Bayraktar
- Faculty of Engineering and Architecture, Department of Civil Engineering, Kastamonu University, Kuzeykent, Kastamonu, Turkey.
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Parvan MG, Voicu G, Badanoiu AI, Nicoara AI, Vasile E. CO 2 Sequestration in the Production of Portland Cement Mortars with Calcium Carbonate Additions. Nanomaterials (Basel) 2021; 11:875. [PMID: 33808156 DOI: 10.3390/nano11040875] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 03/25/2021] [Accepted: 03/27/2021] [Indexed: 11/30/2022]
Abstract
The paper presents the obtention and characterization of Portland cement mortars with limestone filler and nano-calcite additions. The nano-calcite was obtained by the injection of CO2 in a nano-Ca(OH)2 suspension. The resulted nano-CaCO3 presents different morphologies, i.e., polyhedral and needle like crystals, depending on the initial Ca(OH)2 concentration of the suspension. The formation of calcium carbonate in suspensions was confirmed by X-ray diffraction (XRD), complex thermal analysis (DTA-TG), scanning electron microscopy (SEM) and transmission electron microscopy (TEM and HRTEM). This demonstrates the viability of this method to successfully sequestrate CO2 in cement-based materials. The use of this type of nano-CaCO3 in mortar formulations based on PC does not adversely modify the initial and final setting time of cements; for all studied pastes, the setting time decreases with increase of calcium carbonate content (irrespective of the particle size). Specific hydrated phases formed by Portland cement hydration were observed in all mortars, with limestone filler additions or nano-CaCO3, irrespective of curing time. The hardened mortars with calcium carbonate additions (in adequate amounts) can reach the same mechanical strengths as reference (Portland cement mortar). The addition of nano-CaCO3 in the raw mix increases the mechanical strengths, especially at shorter hardening periods (3 days).
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Glinicki MA, Gołaszewski J, Cygan G. Formwork Pressure of a Heavyweight Self-Compacting Concrete Mix. Materials (Basel) 2021; 14:ma14061549. [PMID: 33809977 PMCID: PMC8004881 DOI: 10.3390/ma14061549] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 03/12/2021] [Accepted: 03/19/2021] [Indexed: 11/21/2022]
Abstract
High-fluidity and self-compacting concrete (SCC) mixes were developed using special aggregates for radiation-shielding concrete. The special aggregates comprised heavyweight and hydrous aggregates (crushed magnetite, crushed serpentine, and their mixtures), which were selected to provide an enhanced attenuation of gamma and neutron radiation, respectively. For the mixed concrete design with a bulk density of up to 3570 kg/m3, two cement types were used: Portland cement CEM I and slag cement CEM III/A. The basic properties of the fresh self-compacting concrete were evaluated and the lateral formwork pressure exerted by the freshly mixed self-compacting concrete was measured and analyzed. An original test setup was developed for the determination of the lateral pressure on the square column formwork with pressure measurements carried out using six strain gauge pressure transducers, which was adequate for heavyweight concrete mixture testing. Self-compacting concrete mixtures containing a magnetite aggregate or blends of serpentine and magnetite aggregates with a slump flow of at least 550 mm were developed. The lateral pressure on the formwork was directly proportional to the density of the self-compacting heavyweight concrete mixes. The maximum values of the lateral pressure recorded in the test at a casting speed of 1.5 m/h did not exceed 27 kPa and 55% of hydrostatic pressure. Concrete mixtures with basalt, magnetite, and magnetite/serpentine blended aggregates were found to develop sufficient shear strength for proper stability during casting.
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Affiliation(s)
- Michał A. Glinicki
- Institute of Fundamental Technological Research, Polish Academy of Sciences, Pawinskiego Street 5 B, 02-106 Warszawa, Poland;
| | - Jacek Gołaszewski
- Department of Building Processes and Building Physics, Faculty of Civil Engineering, Silesian University of Technology, Akademicka Street 5, 44-100 Gliwice, Poland
- Correspondence:
| | - Grzegorz Cygan
- Laboratory of Civil Engineering, Faculty of Civil Engineering, Silesian University of Technology, Boleslawa Krzywoustego Street 7, 44-100 Gliwice, Poland;
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Park S, Park JK, Lee N, Kim MO. Exploring Structural Evolution of Portland Cement Blended with Supplementary Cementitious Materials in Seawater. Materials (Basel) 2021; 14:1210. [PMID: 33806644 DOI: 10.3390/ma14051210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 02/23/2021] [Accepted: 03/01/2021] [Indexed: 11/29/2022]
Abstract
The present study investigated the structural evolution of Portland cement (PC) incorporating supplementary cementitious materials (SCMs) exposed to seawater. The samples were made with replacing Portland cement with 10 mass-% silica fume, metakaolin or glass powder. The reaction degree of SCMs estimated by the portlandite consumption shows that metakaolin has the highest reaction degree, thus metakaolin-blended PC exhibits the highest strength. The control exposed to seawater exhibited 14.82% and 12.14% higher compressive strengths compared to those cured in tap water at 7 and 28 days. The samples incorporating metakaolin showed the highest compressive strength of 76.60 MPa at 90 days tap water curing and this was 17% higher than that of the control. Exposure to seawater is found to retard the rate of hydration in all SCM-incorporating systems, while the strength development of the neat PC system is enhanced. The main reaction product that forms during exposure to seawater is Cl-AFm and brucite, while it is predicted by the thermodynamic modelling that a significant amount of M-S-H, calcite and hydrotalcite is to form at an extended period of exposure time.
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Bheel N, Mahro SK, Adesina A. Influence of coconut shell ash on workability, mechanical properties, and embodied carbon of concrete. Environ Sci Pollut Res Int 2021; 28:5682-5692. [PMID: 32970258 DOI: 10.1007/s11356-020-10882-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 09/15/2020] [Indexed: 06/11/2023]
Abstract
The significant contribution of the carbon dioxide emission from the production of Portland cement which is the main binder used in concrete has called for an imminent need to find environmentally friendly materials as alternatives. The availability of large quantities of agricultural wastes such as coconut shell in most developing countries opens a pathway to explore how these materials can be recycled into concrete as the binder composition. The combustion of most solid agricultural wastes results in the production of ash which can be used to replace Portland cement as a binder in concrete. This paper presents the results from the experimental investigation of the effect of coconut shell ash on the workability, mechanical properties, and embodied carbon of concrete. A total of five mixtures were made with coconut shell ash replacing Portland cement up to 20%. Results from this paper showed that coconut shell ash can be incorporated into concrete mixtures to reduce its embodied carbon. A reduction in embodied carbon of about 15% was achieved when 20% of Portland cement was replaced with coconut shell ash. The incorporation of coconut shell ash into concrete mixtures also resulted in an increase in the mechanical properties up to 10% replacement of Portland cement. The compressive, tensile, and flexural strength of mixtures incorporating 10% coconut shell ash as replacement of Portland cement is 12%, 10%, and 9% higher than that of the control mixture without coconut shell ash.
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Affiliation(s)
- Naraindas Bheel
- Department of Civil Engineering, Hyderabad College of Science & Technology, Hyderabad, Pakistan
| | - Santosh Kumar Mahro
- Institute of Environmental Engineering & Management, Mehran University of Engineering and Technology, Jamshoro, Pakistan
| | - Adeyemi Adesina
- Department of Civil and Environmental Engineering, University of Windsor, Windsor, Canada.
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Moreno de Los Reyes AM, Suárez-Navarro JA, Alonso MDM, Gascó C, Sobrados I, Puertas F. New Approach for the Determination of Radiological Parameters on Hardened Cement Pastes with Coal Fly Ash. Materials (Basel) 2021; 14:475. [PMID: 33494137 DOI: 10.3390/ma14030475] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 01/12/2021] [Accepted: 01/13/2021] [Indexed: 11/17/2022]
Abstract
Supplementary cementitious materials (SCMs) in industrial waste and by-products are routinely used to mitigate the adverse environmental effects of, and lower the energy consumption associated with, ordinary Portland cement (OPC) manufacture. Many such SCMs, such as type F coal fly ash (FA), are naturally occurring radioactive materials (NORMs). 226Ra, 232Th and 40K radionuclide activity concentration, information needed to determine what is known as the gamma-ray activity concentration index (ACI), is normally collected from ground cement samples. The present study aims to validate a new method for calculating the ACI from measurements made on unground 5 cm cubic specimens. Mechanical, mineralogical and radiological characterisation of 28-day OPC + FA pastes (bearing up to 30 wt % FA) were characterised to determine their mechanical, mineralogical and radiological properties. The activity concentrations found for 226Ra, 212Pb, 232Th and 40K in hardened, intact 5 cm cubic specimens were also statistically equal to the theoretically calculated values and to the same materials when ground to a powder. These findings consequently validated the new method. The possibility of determining the activity concentrations needed to establish the ACI for cement-based materials on unground samples introduces a new field of radiological research on actual cement, mortar and concrete materials.
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Bravo Eslava LM, Gallardo Gutiérrez CA. [Comparison of the porosity characteristics of Portland cement, mineral trioxide aggregate and Biodentine by scanning electron microscopy]. Rev Cient Odontol (Lima) 2021; 9:e043. [PMID: 38464406 PMCID: PMC10919816 DOI: 10.21142/2523-2754-0901-2021-043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 02/02/2021] [Indexed: 03/12/2024] Open
Abstract
Objective The purpose of this study was to compare the porosity characteristics of Portland cement, mineral trioxide aggregate (MTA) Angelus® and Biodentine Septodont® by scanning electron microscopy. Materials and Methods Cements were prepared according to the manufacturer's instructions and packed in cylindrical polyethylene tubes with an internal diameter of 10 mm and a height of 5 mm. The porosity of the samples was analyzed using scanning electron microscopy. Statistical analyses were performed using the Kruskall Wallis test. The level of significance was established at 0.05. Results The largest size mean diameter valus was found with Portland cement (11.07). There were significant differences between the mean pore diameters (p = 0.05). MTA Angelus® had the largest number of pores, followed by Biodentine Septodont®, and finally, Portland. There were no significant differences in the pores of the three cements (p = 0.09). Conclusion The results of this comparative analysis of endodontic cements showed that Portland cement has a larger pore diameter than MTA Angelus® and Biodentine Septodont®, demonstrating that these latter two cements present better resistance and permeability properties, and thereby prevent microleakage.
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Affiliation(s)
- Luis Manuel Bravo Eslava
- División de Carielogía y Endodoncia de la Carrera de Odontología, Universidad Científica del Sur. Lima, Perú. , Universidad Científica del Sur División de Carielogía y Endodoncia Carrera de Odontología Universidad Científica del Sur Lima Peru
| | - César Antonio Gallardo Gutiérrez
- División de Carielogía y Endodoncia de la Carrera de Odontología, Universidad Científica del Sur. Lima, Perú. , Universidad Científica del Sur División de Carielogía y Endodoncia Carrera de Odontología Universidad Científica del Sur Lima Peru
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Sodol KA, Kaczmarek Ł, Szer J. Fire-Temperature Influence on Portland and Calcium Sulfoaluminate Blend Composites. Materials (Basel) 2020; 13:ma13225230. [PMID: 33228047 PMCID: PMC7699428 DOI: 10.3390/ma13225230] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 11/01/2020] [Accepted: 11/17/2020] [Indexed: 11/16/2022]
Abstract
This paper presents the research data of the fire-temperature influence on Portland CEM I (OPC) and calcium sulfoaluminate (CSA) types of cement blend composites as cooling materials dedicated for infill and covers in fire systems. The data present the material responses for four types at high-temperature elevation times (0, 15, 30, 60 min), such as core heat curves, differences in specimens color, flexural and compressive strength parameters. Materials were tested using the DSC method to collect information about enthalpies. The differences between cement blend composites were compared with commonly used cooling materials such as gypsum blends. It is shown that modifications to Portland cement composites by calcium sulfoaluminate cement have a significant influence on the cooling performance during high-temperature, even for 60 min of exposure. The temperature increase rates in the material core were slower in composites with regards to additionally containing calcium sulfoaluminate in 100–150 °C range. After 60 min of high-temperature elevation, the highest flexural and compressive strength was 75% OPC/25% CSA cement composition. The influence on cooling properties was not related to strength properties. The presented solution may have a significant influence as a passive extinguisher solution of future fire resistance systems in civil engineering.
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Affiliation(s)
- Konrad A. Sodol
- Institute of Materials Science and Engineering, Lodz University of Technology, 90-924 Łódź, Poland;
- Correspondence:
| | - Łukasz Kaczmarek
- Institute of Materials Science and Engineering, Lodz University of Technology, 90-924 Łódź, Poland;
| | - Jacek Szer
- Department of Building Physics and Building Materials, Lodz University of Technology, 90-924 Łódź, Poland;
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Vu VA, Cloutier A, Bissonnette B, Blanchet P, Dagenais C. Steatite Powder Additives in Wood-Cement Drywall Particleboards. Materials (Basel) 2020; 13:ma13214813. [PMID: 33137904 PMCID: PMC7662927 DOI: 10.3390/ma13214813] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 10/18/2020] [Accepted: 10/23/2020] [Indexed: 11/24/2022]
Abstract
The objective of this study was to develop a new drywall wood-based particleboard as an alternative to gypsum board. Various development iterations have led to the use of wood particles, steatite powder and Portland cement. The resulting outcome shows that screw withdrawal resistance was improved by 37% and bending properties by 69% compared to gypsum board of a similar density (0.68–0.70). The raw surface of the boards is of good quality and comparable to the paper-faced surface of gypsum board. Furthermore, the reaction to fire was evaluated through bench-scale test with a cone calorimeter. The investigated particleboard did not reveal visual signs of combustion after 20 min when exposed to a radiant heat of 50 kW/m2, while burning of the overlay paper of gypsum board occurred at about 57 s, suggesting that wood-cement-steatite powder particleboard could be classified as a quasi non-combustible material.
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Affiliation(s)
- Viet-Anh Vu
- Department of Wood and Forest Sciences, Université Laval, Quebec, QC G1V 0A6, Canada; (V.-A.V.); (P.B.); (C.D.)
| | - Alain Cloutier
- Department of Wood and Forest Sciences, Université Laval, Quebec, QC G1V 0A6, Canada; (V.-A.V.); (P.B.); (C.D.)
- Correspondence: ; Tel.: +1-418-656-5851
| | - Benoît Bissonnette
- Department of Civil and Water Engineering, Université Laval, Quebec, QC G1V 0A6, Canada;
| | - Pierre Blanchet
- Department of Wood and Forest Sciences, Université Laval, Quebec, QC G1V 0A6, Canada; (V.-A.V.); (P.B.); (C.D.)
| | - Christian Dagenais
- Department of Wood and Forest Sciences, Université Laval, Quebec, QC G1V 0A6, Canada; (V.-A.V.); (P.B.); (C.D.)
- FPInnovations, Quebec, QC G1V 4C7, Canada
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Hameed R, Seo J, Park S, Amr IT, Lee HK. CO 2 Uptake and Physicochemical Properties of Carbonation-Cured Ternary Blend Portland Cement-Metakaolin-Limestone Pastes. Materials (Basel) 2020; 13:E4656. [PMID: 33086553 DOI: 10.3390/ma13204656] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 10/08/2020] [Accepted: 10/15/2020] [Indexed: 11/17/2022]
Abstract
The feasibility of carbonation curing of ternary blend Portland cement-metakaolin-limestone was investigated. Portland cement was substituted by the combination of metakaolin and limestone at levels of 15%, 30%, and 45% by the mass. The ternary blends were cured with four different combinations of ambient and carbonation curing. The mechanical property, CO2 uptake, and mineralogical variations of the ternary blend pastes were investigated by means of compressive strength test, thermogravimetric analysis, and X-ray diffractometry. In addition, volume of permeable voids and sorptivity of the ternary blends were also presented to provide a fundamental idea of the pore characteristics of the blends. The test results showed that the increasing amount of metakaolin and limestone enhanced the CO2 uptake, reaching 20.7% for the sample with a 45% cement replacement level at 27 d of carbonation. Meanwhile, the compressive strength of the samples was reduced up to 65% upon excessive incorporation of metakaolin and limestone. The samples with a replacement level of 15% exhibited a comparable strength and volume of permeable voids to those of the sample without substitution, proving that the ternary blend Portland cement-metakaolin-limestone can be a viable option toward the development of eco-friendly binders.
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Teixeira CDS, Wasielewsky JC, Dos Santos GS, Bernardi A, Bortoluzzi EA, Garcia LDFR. Effect of the addition of nanoparticles of CaCO 3 and different water-to-powder ratios on the physicochemical properties of white Portland cement. Microsc Res Tech 2020; 84:592-601. [PMID: 33047854 DOI: 10.1002/jemt.23617] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 09/23/2020] [Accepted: 09/29/2020] [Indexed: 11/09/2022]
Abstract
The addition of calcium carbonate nanoparticles (nano-CaCO3 ) accelerates the hydration of Portland cement improving its mechanical properties. Conversely, nano-CaCO3 addition leads to reduction in the water required during initial PC hydration. Therefore, the use of a correct water-to-powder ratio is fundamental for manipulating this hydraulic cement. This study evaluated the effect of nano-CaCO3 addition and different water-to-powder ratios on the physicochemical properties of white Portland cement (WPC). WPC was associated to different concentrations of nano-CaCO3 , and the following experimental groups were created: G1a (no nano-CaCO3 ); G2a (0.5% nano-CaCO3 ), G3a (1% nano-CaCO3 ), G4a (2% nano-CaCO3 ), and G5a (5% nano-CaCO3 ). The setting-time (ST), compressive strength (CS), dimensional change (DC), solubility (S), and pH were assessed (24 hr and 30 days). Next, WPC + 5% nano-CaCO3 was manipulated varying the water-to-powder ratio: G1b (WPC/0.33 ml); G2b (WPC/nano-CaCO3 /0.33 ml); G3b (WPC/0.29 ml); G4b (WPC/nano-CaCO3 /0.29 ml); G5b (WPC/0.26 ml); and G6b (WPC/nano-CaCO3 /0.26 ml). The tests were repeated. The data analysis (2-way ANOVA and Tukey test, α = 5%) demonstrated that ST was shorter for samples containing nano-CaCO3 (p < .05). Reduction in CS was observed for all groups at 30 days, except G5a, G2b, and G6b (p < .05). DC and S had no statistical difference among groups (p > .05) independently of nano-CaCO3 water-to-powder ratio. After 30 days, there was significant reduction in pH for G3a and G6b (p < .05). The different concentrations of nano-CaCO3 and water-to-powder ratios affected the physicochemical properties of WPC, especially the setting-time and compressive strength.
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Affiliation(s)
- Cleonice da Silveira Teixeira
- Department of Dentistry, Endodontics Division, Health Sciences Center, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | - Jessica Coelho Wasielewsky
- Department of Dentistry, Endodontics Division, Health Sciences Center, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | - Giovanna Slongo Dos Santos
- Department of Dentistry, Endodontics Division, Health Sciences Center, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | - Anarela Bernardi
- Department of Dentistry, Endodontics Division, Health Sciences Center, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | - Eduardo Antunes Bortoluzzi
- Department of Dentistry, Endodontics Division, Health Sciences Center, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | - Lucas da Fonseca Roberti Garcia
- Department of Dentistry, Endodontics Division, Health Sciences Center, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil
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Buczyński P, Iwański M, Mazurek G, Krasowski J, Krasowski M. Effects of Portland Cement and Polymer Powder on the Properties of Cement-Bound Road Base Mixtures. Materials (Basel) 2020; 13:E4253. [PMID: 32987755 DOI: 10.3390/ma13194253] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 09/16/2020] [Accepted: 09/18/2020] [Indexed: 11/18/2022]
Abstract
This article presents the test results for the physical and mechanical properties and fracture toughness of polymer-modified hydraulically-bound mixtures (HBM) produced with Portland cement for road base layers. The modifier used was a redispersible polymer powder (RPP) based on a vinyl ethylene acetate (EVA) copolymer obtained by spray drying. A three-level full factorial design with two factors was applied to determine the contents of Portland cement and polymer powder in the cement-bound mixture (CBM). Both Portland cement and polymer powder were added at three levels: 0%, 2%, and 4%. The assessment included basic physical properties (water absorption, density, and bulk density) and mechanical properties (stiffness modulus, axial compressive strength, and indirect tensile strength) of the CBM. Particular attention was paid to the assessment of fracture toughness in the semi-circular bending test. The results of the research show that polymer powder positively influenced the mechanical properties of CBM by improving its cohesion while maintaining its stiffness. Another benefit coming from the use of polymer powder was the CBM’s increased resistance to cracking, which is the desired characteristic from the perspective of pavement durability.
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Tolba E, Wang S, Wang X, Neufurth M, Ackermann M, Muñoz-Espí R, Abd El-Hady BM, Schröder HC, Müller WEG. Self-Healing Properties of Bioinspired Amorphous CaCO 3/Polyphosphate-Supplemented Cement. Molecules 2020; 25:E2360. [PMID: 32438652 PMCID: PMC7287741 DOI: 10.3390/molecules25102360] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 05/13/2020] [Accepted: 05/15/2020] [Indexed: 12/27/2022] Open
Abstract
There is a strong interest in cement additives that are able to prevent or mitigate the adverse effects of cracks in concrete that cause corrosion of the reinforcement. Inorganic polyphosphate (polyP), a natural polymer that is synthesized by bacteria, even those on cement/concrete, can increase the resistance of concrete to progressive damage from micro-cracking. Here we use a novel bioinspired strategy based on polyP-stabilized amorphous calcium carbonate (ACC) to give this material self-healing properties. Portland cement was supplemented with ACC nanoparticles which were stabilized with 10% (w/w) Na-polyP. Embedding these particles in the hydrated cement resulted in the formation of calcite crystals after a hardening time of 10 days, which were not seen in controls, indicating that the particles dissolve and then transform into calcite. While there was no significant repair in the controls without ACC, almost complete closure of the cracks was observed after a 10 days healing period in the ACC-supplemented samples. Nanoindentation measurements on the self-healed crack surfaces showed a similar or slightly higher elasticity at a lower hardness compared to non-cracked surfaces. Our results demonstrate that bioinspired approaches, like the use of polyP-stabilized ACC shown here, can significantly improve the repair capacity of Portland cement.
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Affiliation(s)
- Emad Tolba
- ERC Advanced Investigator Grant Research Group at the Institute for Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, 55128 Mainz, Germany; (E.T.); (S.W.); (M.N.); (H.C.S.)
- Polymers and Pigments Department, National Research Center, Dokki, Giza 12622, Egypt;
| | - Shunfeng Wang
- ERC Advanced Investigator Grant Research Group at the Institute for Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, 55128 Mainz, Germany; (E.T.); (S.W.); (M.N.); (H.C.S.)
| | - Xiaohong Wang
- ERC Advanced Investigator Grant Research Group at the Institute for Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, 55128 Mainz, Germany; (E.T.); (S.W.); (M.N.); (H.C.S.)
| | - Meik Neufurth
- ERC Advanced Investigator Grant Research Group at the Institute for Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, 55128 Mainz, Germany; (E.T.); (S.W.); (M.N.); (H.C.S.)
| | - Maximilian Ackermann
- Institute of Functional and Clinical Anatomy, University Medical Center of the Johannes Gutenberg University, Johann Joachim Becher Weg 13, 55099 Mainz, Germany;
| | - Rafael Muñoz-Espí
- Institute of Materials Science (ICMUV), Universitat de València, C/Catedràtic José Beltrán 2, 46980 Paterna, València, Spain;
| | | | - Heinz C. Schröder
- ERC Advanced Investigator Grant Research Group at the Institute for Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, 55128 Mainz, Germany; (E.T.); (S.W.); (M.N.); (H.C.S.)
- NanotecMARIN GmbH, Mühlstr. 19, 55218 Ingelheim am Rhein, Germany
| | - Werner E. G. Müller
- ERC Advanced Investigator Grant Research Group at the Institute for Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, 55128 Mainz, Germany; (E.T.); (S.W.); (M.N.); (H.C.S.)
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