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Saleh MA, Su Z, Zhang J. Novel sustainable steel fiber reinforced preplaced aggregate concrete incorporating Portland limestone cement. Sci Rep 2024; 14:10937. [PMID: 38740812 DOI: 10.1038/s41598-024-60391-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Accepted: 04/23/2024] [Indexed: 05/16/2024] Open
Abstract
This study proposes a novel approach by adding Portland limestone cement (PLC) to preplaced aggregate steel fiber reinforced concrete (PASFRC) to create a sustainable concrete that minimizes CO2 emissions and cement manufacturing energy usage. The method involves injected a flowable grout after premixing and preplacing steel-fibers and aggregates in the formwork. This study evaluates the mechanical properties of a novel sustainable concrete that uses PLC and steel fibers. To achieve the intended objective, long and short end-hooked steel fibers of 1%, 2%, 3%, and 6% were incorporated in PASFRC. Also, Analysis of variance (ANOVA) was used to examine the data. Results indicated that PLC and higher fiber doses increased the mechanical properties of PAC. At 90 days, PASFRC mixtures containing 6% long steel fibers demonstrated superior compressive, tensile, and flexural strengths, registering the highest values of 49.8 MPa, 7.7 MPa, and 10.9 MPa, respectively and differed by 188%, 166%, and 290%, respectively from fiberless PAC. The study confirmed the suitability and effectiveness of using PLC with steel fibers in PAC which significantly improved the mechanical properties of PASFRC. This was verified through analytical analysis and new empirical equations were proposed to predict the mechanical properties of PASFRC.
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Affiliation(s)
- Majed Ali Saleh
- School of Civil and Hydraulic Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
- Civil Engineering Department, College of Engineering, University of Zintan, Zintan, Libya
| | - Zhihao Su
- School of Civil and Hydraulic Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Ji Zhang
- School of Civil and Hydraulic Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China.
- National Center of Technology Innovation for Digital Construction, Wuhan, 430074, China.
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2
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Ram K, Serdar M, Londono-Zuluaga D, Scrivener K. Does carbon footprint reduction impair mechanical properties and service life of concrete? MATERIALS AND STRUCTURES 2022; 56:6. [PMID: 36593923 PMCID: PMC9800350 DOI: 10.1617/s11527-022-02090-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 12/07/2022] [Indexed: 06/17/2023]
Abstract
UNLABELLED The aim of this study is to evaluate how much the changes in the concrete mix design, which enable carbon footprint reduction, are impacting mechanical properties and predicted service life of concrete structure. The starting point of this study was concrete mix used in a recent reinforced concrete Pelješac Bridge in the Adriatic. In the first round of experiments the amount of cement in this initial mix was significantly lowered, without jeopardising workability of the mix. In the second round, the main part of the cement was substituted with the combination of fly ash and limestone or calcined clay and limestone. All supplementary cementitious materials used were sourced in the region of the structure. The calcined clays used in this study were collected locally and found to have a low kaolin content. On all mixes fresh and mechanical properties were tested to ensure that the requested equal or better workability and mechanical stability were reached. Furthermore, on each mix chloride migration was tested to evaluate the resistance of mix to chloride penetration. All mixtures were evaluated based on the overall performance considering mechanical, durability, and carbon footprints. The results indicate that the total cement content had a significant effect on durability and thus service life. The bridge mix design was determined to be 'over designed,' as all alternative mixes achieved a similar or higher sustainability index with lower amount of cement. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1617/s11527-022-02090-9.
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Affiliation(s)
- Kiran Ram
- Department of Materials, Faculty of Civil Engineering, University of Zagreb, 10000 Zagreb, Croatia
| | - Marijana Serdar
- Department of Materials, Faculty of Civil Engineering, University of Zagreb, 10000 Zagreb, Croatia
| | - Diana Londono-Zuluaga
- Laboratory of Construction Materials, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Karen Scrivener
- Laboratory of Construction Materials, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
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3
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Coppola L, Beretta S, Bignozzi MC, Bolzoni F, Brenna A, Cabrini M, Candamano S, Caputo D, Carsana M, Cioffi R, Coffetti D, Colangelo F, Crea F, De Gisi S, Diamanti MV, Ferone C, Frontera P, Gastaldi MM, Labianca C, Lollini F, Lorenzi S, Manzi S, Marroccoli M, Notarnicola M, Ormellese M, Pastore T, Pedeferri M, Petrella A, Redaelli E, Roviello G, Telesca A, Todaro F. The Improvement of Durability of Reinforced Concretes for Sustainable Structures: A Review on Different Approaches. MATERIALS 2022; 15:ma15082728. [PMID: 35454421 PMCID: PMC9029423 DOI: 10.3390/ma15082728] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 04/04/2022] [Accepted: 04/06/2022] [Indexed: 01/25/2023]
Abstract
The topic of sustainability of reinforced concrete structures is strictly related with their durability in aggressive environments. In particular, at equal environmental impact, the higher the durability of construction materials, the higher the sustainability. The present review deals with the possible strategies aimed at producing sustainable and durable reinforced concrete structures in different environments. It focuses on the design methodologies as well as the use of unconventional corrosion-resistant reinforcements, alternative binders to Portland cement, and innovative or traditional solutions for reinforced concrete protection and prevention against rebars corrosion such as corrosion inhibitors, coatings, self-healing techniques, and waterproofing aggregates. Analysis of the scientific literature highlights that there is no preferential way for the production of “green” concrete but that the sustainability of the building materials can only be achieved by implementing simultaneous multiple strategies aimed at reducing environmental impact and improving both durability and performances.
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Affiliation(s)
- Luigi Coppola
- Department of Engineering and Applied Sciences, Università di Bergamo, Viale Marconi 5, 24044 Dalmine, Italy; (M.C.); (D.C.); (S.L.); (T.P.)
- Correspondence: ; Tel.: +39-035-205-2316
| | - Silvia Beretta
- Department of Chemistry, Materials and Chemical Engineering “G. Natta”, Politecnico di Milano, Via Mancinelli 7, 20131 Milan, Italy; (S.B.); (F.B.); (A.B.); (M.C.); (M.V.D.); (M.M.G.); (F.L.); (M.O.); (M.P.); (E.R.)
| | - Maria Chiara Bignozzi
- Department of Civil, Chemical, Environmental and Materials Engineering, Università di Bologna, Via Terracini 28, 40131 Bologna, Italy; (M.C.B.); (S.M.)
| | - Fabio Bolzoni
- Department of Chemistry, Materials and Chemical Engineering “G. Natta”, Politecnico di Milano, Via Mancinelli 7, 20131 Milan, Italy; (S.B.); (F.B.); (A.B.); (M.C.); (M.V.D.); (M.M.G.); (F.L.); (M.O.); (M.P.); (E.R.)
| | - Andrea Brenna
- Department of Chemistry, Materials and Chemical Engineering “G. Natta”, Politecnico di Milano, Via Mancinelli 7, 20131 Milan, Italy; (S.B.); (F.B.); (A.B.); (M.C.); (M.V.D.); (M.M.G.); (F.L.); (M.O.); (M.P.); (E.R.)
| | - Marina Cabrini
- Department of Engineering and Applied Sciences, Università di Bergamo, Viale Marconi 5, 24044 Dalmine, Italy; (M.C.); (D.C.); (S.L.); (T.P.)
| | - Sebastiano Candamano
- Department of Mechanical, Energy and Management Engineering, Università della Calabria, Via Bucci-Cubo 46C, 87036 Rende, Italy; (S.C.); (F.C.)
| | - Domenico Caputo
- Department of Chemical, Materials and Industrial Engineering, Università “Federico II” di Napoli, Piazzale Tecchio 80, 80125 Naples, Italy;
| | - Maddalena Carsana
- Department of Chemistry, Materials and Chemical Engineering “G. Natta”, Politecnico di Milano, Via Mancinelli 7, 20131 Milan, Italy; (S.B.); (F.B.); (A.B.); (M.C.); (M.V.D.); (M.M.G.); (F.L.); (M.O.); (M.P.); (E.R.)
| | - Raffaele Cioffi
- Department of Engineering, Università Parthenope di Napoli, Via Amm. Acton 38, 80133 Naples, Italy; (R.C.); (F.C.); (C.F.); (G.R.)
| | - Denny Coffetti
- Department of Engineering and Applied Sciences, Università di Bergamo, Viale Marconi 5, 24044 Dalmine, Italy; (M.C.); (D.C.); (S.L.); (T.P.)
| | - Francesco Colangelo
- Department of Engineering, Università Parthenope di Napoli, Via Amm. Acton 38, 80133 Naples, Italy; (R.C.); (F.C.); (C.F.); (G.R.)
| | - Fortunato Crea
- Department of Mechanical, Energy and Management Engineering, Università della Calabria, Via Bucci-Cubo 46C, 87036 Rende, Italy; (S.C.); (F.C.)
| | - Sabino De Gisi
- Department of Civil, Environmental, Land, Building Engineering and Chemistry, Politecnico di Bari, Via Orabona 4, 70126 Bari, Italy; (S.D.G.); (C.L.); (M.N.); (A.P.); (F.T.)
| | - Maria Vittoria Diamanti
- Department of Chemistry, Materials and Chemical Engineering “G. Natta”, Politecnico di Milano, Via Mancinelli 7, 20131 Milan, Italy; (S.B.); (F.B.); (A.B.); (M.C.); (M.V.D.); (M.M.G.); (F.L.); (M.O.); (M.P.); (E.R.)
| | - Claudio Ferone
- Department of Engineering, Università Parthenope di Napoli, Via Amm. Acton 38, 80133 Naples, Italy; (R.C.); (F.C.); (C.F.); (G.R.)
| | - Patrizia Frontera
- Department of Civil Engineering, Energy, Environmental and Materials, Università Mediterranea di Reggio Calabria, Via dell’Università 25, 89122 Reggio Calabria, Italy;
| | - Matteo Maria Gastaldi
- Department of Chemistry, Materials and Chemical Engineering “G. Natta”, Politecnico di Milano, Via Mancinelli 7, 20131 Milan, Italy; (S.B.); (F.B.); (A.B.); (M.C.); (M.V.D.); (M.M.G.); (F.L.); (M.O.); (M.P.); (E.R.)
| | - Claudia Labianca
- Department of Civil, Environmental, Land, Building Engineering and Chemistry, Politecnico di Bari, Via Orabona 4, 70126 Bari, Italy; (S.D.G.); (C.L.); (M.N.); (A.P.); (F.T.)
| | - Federica Lollini
- Department of Chemistry, Materials and Chemical Engineering “G. Natta”, Politecnico di Milano, Via Mancinelli 7, 20131 Milan, Italy; (S.B.); (F.B.); (A.B.); (M.C.); (M.V.D.); (M.M.G.); (F.L.); (M.O.); (M.P.); (E.R.)
| | - Sergio Lorenzi
- Department of Engineering and Applied Sciences, Università di Bergamo, Viale Marconi 5, 24044 Dalmine, Italy; (M.C.); (D.C.); (S.L.); (T.P.)
| | - Stefania Manzi
- Department of Civil, Chemical, Environmental and Materials Engineering, Università di Bologna, Via Terracini 28, 40131 Bologna, Italy; (M.C.B.); (S.M.)
| | - Milena Marroccoli
- School of Engineering, Università della Basilicata, Viale dell’Ateneo Lucano 10, 85100 Potenza, Italy; (M.M.); (A.T.)
| | - Michele Notarnicola
- Department of Civil, Environmental, Land, Building Engineering and Chemistry, Politecnico di Bari, Via Orabona 4, 70126 Bari, Italy; (S.D.G.); (C.L.); (M.N.); (A.P.); (F.T.)
| | - Marco Ormellese
- Department of Chemistry, Materials and Chemical Engineering “G. Natta”, Politecnico di Milano, Via Mancinelli 7, 20131 Milan, Italy; (S.B.); (F.B.); (A.B.); (M.C.); (M.V.D.); (M.M.G.); (F.L.); (M.O.); (M.P.); (E.R.)
| | - Tommaso Pastore
- Department of Engineering and Applied Sciences, Università di Bergamo, Viale Marconi 5, 24044 Dalmine, Italy; (M.C.); (D.C.); (S.L.); (T.P.)
| | - MariaPia Pedeferri
- Department of Chemistry, Materials and Chemical Engineering “G. Natta”, Politecnico di Milano, Via Mancinelli 7, 20131 Milan, Italy; (S.B.); (F.B.); (A.B.); (M.C.); (M.V.D.); (M.M.G.); (F.L.); (M.O.); (M.P.); (E.R.)
| | - Andrea Petrella
- Department of Civil, Environmental, Land, Building Engineering and Chemistry, Politecnico di Bari, Via Orabona 4, 70126 Bari, Italy; (S.D.G.); (C.L.); (M.N.); (A.P.); (F.T.)
| | - Elena Redaelli
- Department of Chemistry, Materials and Chemical Engineering “G. Natta”, Politecnico di Milano, Via Mancinelli 7, 20131 Milan, Italy; (S.B.); (F.B.); (A.B.); (M.C.); (M.V.D.); (M.M.G.); (F.L.); (M.O.); (M.P.); (E.R.)
| | - Giuseppina Roviello
- Department of Engineering, Università Parthenope di Napoli, Via Amm. Acton 38, 80133 Naples, Italy; (R.C.); (F.C.); (C.F.); (G.R.)
| | - Antonio Telesca
- School of Engineering, Università della Basilicata, Viale dell’Ateneo Lucano 10, 85100 Potenza, Italy; (M.M.); (A.T.)
| | - Francesco Todaro
- Department of Civil, Environmental, Land, Building Engineering and Chemistry, Politecnico di Bari, Via Orabona 4, 70126 Bari, Italy; (S.D.G.); (C.L.); (M.N.); (A.P.); (F.T.)
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Sitarz M, Castro-Gomes J, Hager I. Strength and Microstructure Characteristics of Blended Fly Ash and Ground Granulated Blast Furnace Slag Geopolymer Mortars with Na and K Silicate Solution. MATERIALS (BASEL, SWITZERLAND) 2021; 15:211. [PMID: 35009357 PMCID: PMC8745972 DOI: 10.3390/ma15010211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 12/13/2021] [Accepted: 12/27/2021] [Indexed: 06/14/2023]
Abstract
Mineral geopolymer binders can be an attractive and more sustainable alternative to traditional Portland cement materials for special applications. In geopolymer technology the precursor is a source of silicon and aluminium oxides, the second component is an alkaline solution. In the synthesis of geopolymer binders the most commonly used alkaline solution is a mixture of sodium or potassium water glass with sodium or potassium hydroxide or silicate solution with a low molar ratio, which is more convenient and much safer in use. In this paper, we present the influence of sodium or potassium silicate solution on the physical and mechanical properties of fly ash and ground granulated blast furnace slag-based geopolymer mortars. Mercury intrusion porosimetry and microstructural observation allowed for comparing the structure of materials with a different type of alkaline solution. The evolution of compressive and flexural tensile strength with time determined for composites using 10%, 30% and 50% slag contents (referring to fly ash mass) was analysed. The tests were performed after 3, 7, 14 and 28 days. It was observed that, as the amount of slag used increases in the precursor, the strength of the material grows. Mortars with the sodium alkaline solution were characterised by a higher strength at a young age. However, the values of strength 28 days were higher for geopolymers with potassium alkaline solution reaching 75 MPa in compression. Geopolymer mortar microstructure observation indicates a high matrix heterogeneity with numerous microcracks. Matrix defects may be caused by the rapid kinetics of the material binding reaction or shrinkage associated with the drying of the material.
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Affiliation(s)
- Mateusz Sitarz
- Chair of Building Materials Engineering, Faculty of Civil Engineering, Cracow University of Technology, 31-155 Cracow, Poland;
| | - João Castro-Gomes
- Centre of Materials and Building Technologies (C–MADE), Department of Civil Engineering and Architecture, University of Beira Interior (UBI), 6201-001 Covilhã, Portugal;
| | - Izabela Hager
- Chair of Building Materials Engineering, Faculty of Civil Engineering, Cracow University of Technology, 31-155 Cracow, Poland;
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Ibáñez-Gosálvez J, Real-Herraiz T, Ortega JM. Effects of a Real Exposure Class XC4 Mediterranean Climate Environment in the Behavior of Mortars Made Using Ternary Binders with Addition of Slag, Fly Ash and Limestone. MATERIALS 2021; 14:ma14195848. [PMID: 34640244 PMCID: PMC8510225 DOI: 10.3390/ma14195848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 09/26/2021] [Accepted: 09/30/2021] [Indexed: 11/16/2022]
Abstract
For improving the contribution of the cement industry to mitigate global warming, many strategies have been put into practice, such as the use of eco-friendly cements with the incorporation of additions substituting clinker. Nevertheless, the use of ternary binders for the production of commercial cements is still reduced, particularly in Spain. The purpose of this research is to characterize the long-term influence produced by the exposure to a real in situ inland Mediterranean climate condition in the pore network, parameters related to durability and mechanical performance of mortars made with ternary binders, which incorporated limestone, fly ash, and ground granulated blast-furnace slag, in comparison with mortars without additions and binary blended mortars. The site verified the specifications of exposure class XC4 of Eurocode 2. The ternary and binary binders accomplished the prescriptions of cement type CEM II/B. The pore network was studied with mercury intrusion porosimetry and electrical resistivity. Water absorption, diffusion coefficient, carbonation depth, ultrasonic pulse velocity, compressive and flexural strengths have been determined. The exposure to the environment produced after 250 days an increase in porosity, a loss of pore refinement, a rise of the carbonation depths, and a reduction in the mechanical strengths, highlighting the better overall performance of ternary mortar with both fly ash and slag.
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Affiliation(s)
- Javier Ibáñez-Gosálvez
- Departamento de Ingeniería Civil, Universidad de Alicante, Ap. Correos 99, 03080 Alicante, Spain;
| | - Teresa Real-Herraiz
- Instituto de Matemática Multidisciplinar, Universidad Politécnica de Valencia, Camino de Vera s/n, 46022 Valencia, Spain;
| | - José Marcos Ortega
- Departamento de Ingeniería Civil, Universidad de Alicante, Ap. Correos 99, 03080 Alicante, Spain;
- Correspondence: ; Tel.: +34-96-5903-400 (ext. 2470)
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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. INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCE AND TECHNOLOGY : IJEST 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] [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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Microstructure, Durability and Mechanical Properties of Mortars Prepared Using Ternary Binders with Addition of Slag, Fly Ash and Limestone. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11146388] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In order to improve the contribution to sustainability of cement production, several strategies have been developed, such as the incorporation of additions as clinker replacement. Regarding the production of commercial cements with additions, those made with binary binders are mostly produced. However, the use of ternary binders for manufacturing commercial cements is still very low, at least in Spain, and they could also be an adequate solution for producing eco-friendly cements. The objective of this research is to study the effects in the long term produced by ternary binders which combine the additions of blast furnace slag, fly ash and limestone in the microstructure, durability and mechanical performance of mortars, compared to mortars without additions and mortars made with binary binders. The ternary and binary binders accomplished the prescriptions for a cement type CEM II/B. The microstructure was characterized using mercury intrusion porosimetry, electrical resistivity and differential thermal analysis. Absorption after immersion, diffusion coefficient, mechanical strengths and ultrasonic pulse velocity were studied. The best performance was noted for ternary binder with both slag and fly ash, probably produced by the synergetic effects of slag hydration and fly ash pozzolanic reactions. These effects were more noticeable regarding the compressive strength.
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Alkali-Activated Mortars Modified by Epoxy-Carbon Fiber Composites Wastes. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11136110] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Short chopped fibers coated by epoxy resin of different length (5 to 10 mm length) were added at low volume content (about 4.6% on the composite) to alkali-activated fly ash or metakaolin mortars. These uncured scraps derive from the production of carbon fiber-reinforced polymer composites and they are not presently recycled, despite their outstanding mechanical properties. The workability, microstructure, porosity, and physical and mechanical properties (mainly flexural strength) of the derived materials were investigated. Superior flexural strength and increased toughness were obtained. An acid treatment of the scraps further improved the mechanical properties of the mortars by changing the chemical structure of the surface, thus increasing the interaction with the inorganic phase. These results foster the use of these wastes to improve the performance of low carbon footprint building materials such as alkali-activated composites in the building industry.
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Printability and Setting Time of CSA Cement with Na 2SiO 3 and Gypsum for Binder Jetting 3D Printing. MATERIALS 2021; 14:ma14112811. [PMID: 34070415 PMCID: PMC8197472 DOI: 10.3390/ma14112811] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 05/09/2021] [Accepted: 05/19/2021] [Indexed: 11/17/2022]
Abstract
The purpose of this study is to optimize the composition of CSA (calcium sulfoaluminate) cement with sodium silicate (Na2SiO3) and gypsum for binder jetting 3D printing. The preliminary test was carried out with an applicator to decide the proper thickness of one layer before using the 3D printer. A liquid binder was then selected to maintain the shape of the particles. Based on the results, the optimal mixture of dry materials and a liquid activator was derived through various parametric studies. For dry materials, the optimum composition of CSA cement, gypsum, and sand was suggested, and the liquid activator made with sodium silicate solution and VMA (viscosity modified agent) were selected. The setting time with gypsum and sodium silicate was controlled within 30 s. In case of the delayed setting time and the rapid setting mixture, the jetting line was printed thicker or thinner and the accuracy of the printout was degraded. In order to adjust the viscosity of the liquid activator, 10% of the VMA was used in 35% of sodium silicate solution and the viscosity of 200-400 cP was suitable to be sprayed from the nozzle. With this optimal mixture, a prototype of atypical decorative wall was printed, and the compressive strength was measured at about 7 MPa.
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Using Calcined Marls as Non-Common Supplementary Cementitious Materials—A Critical Review. MINERALS 2021. [DOI: 10.3390/min11050517] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
This review summarizes the major research and scientific findings on the relevance of using calcined marl as supplementary cementitious material in developing eco-friendly cement for the next generation. Incorporation of calcined marl into cement can result in changes in the properties of these binders, and thus compatibility with other additions could be potential challenging, particularly at higher replacement ratios. From the reviewed literature, a detailed investigation on the characterization of calcined marls, activation methods, influencing parameters, along with studies on the hydration and microstructure was discussed, the overall objective aimed at coming up with the optimal physical and chemical parameters to generate highly reactive marl.
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Liu X, Ma B, Tan H, He X, Zhao R, Chen P, Su Y, Yang J. Preparation of ultrafine fly ash by wet grinding and its utilization for immobilizing chloride ions in cement paste. WASTE MANAGEMENT (NEW YORK, N.Y.) 2020; 113:456-468. [PMID: 32599350 DOI: 10.1016/j.wasman.2020.06.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 05/31/2020] [Accepted: 06/16/2020] [Indexed: 06/11/2023]
Abstract
In this study, to promote the chloride binding capacity of coal fired fly ash (RFA) in cementitious materials, wet grinding was employed and ultrafine fly ash (UFA) with D50 = 2.1 μm was prepared; SEM, XRD, TG, FTIR, and XPS were used to evaluate the chemical and physical change in the process of wet grinding. Then, two kinds of binders composed of cement and FA were designed, and the chloride immobilization was comparatively studied in terms of chemical binding, physical binding, and migration resistance. The hydration behavior and hydrates were investigated in terms of TGA, XRD, NMR, and MIP. Results revealed that UFA exhibited higher pozzolanic reactivity due to the increase of specific surface area, destruction of original molecular structure, and exposure of active reaction sites. And chloride immobilization in cement-UFA system was much greater than that in cement-RFA system at ages of 7 d and 28 d. The mechanism behind was discussed in three aspects: (a) chemical binding was promoted because of the more produced chloroaluminates facilitated by the release of aluminum from UFA; (b) physical adsorption was strengthened at 7 d but weakened at 28 d, resulting from the opposite influence on the amount of C-S-H gel at different ages; (c) migration resistance was improved by the reduction of pore volume and the increase in the complexity of pore structure. This investigation provided one new method for processing FA to promote the chloride immobilization of cement-FA system.
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Affiliation(s)
- Xiaohai Liu
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, PR China
| | - Baoguo Ma
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, PR China
| | - Hongbo Tan
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, PR China.
| | - Xingyang He
- School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan 430070, PR China.
| | - Rixu Zhao
- China Construction Ready Mixed Concrete Co., Ltd., Wuhan 430074, PR China
| | - Pian Chen
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, PR China
| | - Ying Su
- School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan 430070, PR China
| | - Jin Yang
- School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan 430070, PR China
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12
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Hybrid Fly Ash-Based Geopolymeric Foams: Microstructural, Thermal and Mechanical Properties. MATERIALS 2020; 13:ma13132919. [PMID: 32610547 PMCID: PMC7372487 DOI: 10.3390/ma13132919] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 06/20/2020] [Accepted: 06/26/2020] [Indexed: 11/17/2022]
Abstract
This research investigates the preparation and characterization of new organic–inorganic geopolymeric foams obtained by simultaneously reacting coal fly ash and an alkali silicate solution with polysiloxane oligomers. Foaming was realized in situ using Si0 as a blowing agent. Samples with density ranging from 0.3 to 0.7 g/cm3 that show good mechanical properties (with compressive strength up to ≈5 MPa for a density of 0.7 g/cm3) along with thermal performances (λ = 0.145 ± 0.001 W/m·K for the foamed sample with density 0.330 g/cm3) comparable to commercial lightweight materials used in the field of thermal insulation were prepared. Since these foams were obtained by valorizing waste byproducts, they could be considered as low environmental impact materials and, hence, with promising perspectives towards the circular economy.
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13
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Inhibition Effect of Tartrate Ions on the Localized Corrosion of Steel in Pore Solution at Different Chloride Concentrations. BUILDINGS 2020. [DOI: 10.3390/buildings10060105] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The aim of this work is the evaluation of the inhibition effect of tartrate ions with respect to the localized corrosion of steel reinforcements in alkaline solution as a function of the concentration of chlorides ions. Weight loss tests and electrochemical tests were carried out in saturated Ca(OH)2 solution with NaOH at pH 12.7 and 13.2. The results only evidence a slight inhibition effect at pH 12.7, whereas at pH 13.2 the pitting onset is inhibited also for chloride concentration up to 3 M. Tartaric acid is a dicarboxylic acid with nucleophile substituents, which can act as a chelating agent both adsorbing on the surface of the passive film and forming a soluble complex with ferrous and ferric ions. Tartrate causes an increase in the passive current density but it prevents the depassivation of carbon steel due to the action of chlorides, thus preventing pitting initiation due to the competitive adsorption on metal surface.
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14
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Mechanical Characterization of Basalt Fabric-Reinforced Alkali-Activated Matrix Composite: A Preliminary Investigation. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10082865] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Fabric-reinforced cementitious composites are a recent family of commercial products devoted to the external retrofitting and strengthening of masonry and concrete structures. In the present work, the authors investigate the possibility of using, as matrix, a mortar based on alkali-activated materials. Basalt textile was selected as reinforcement because it is an effective, low-cost and environmentally friendly reinforcement. The matrix was prepared using by-products of industrial processes. Mortar was characterized by measuring its drying shrinkage, capillary water absorption, compressive and flexural strengths and analyzed using X-Ray diffractometry, Fourier-transform infrared spectroscopy, and thermogravimetric analysis. The mechanical behavior of the composites was investigated through tensile and direct shear tests. The basalt fabric-reinforced alkali-activated matrix composite showed, under tension, a tri-linear response curve, mainly governed by cracks development and widening. The measured ultimate stress, ultimate strain and tensile modulus of elasticity in region III were 434 MPa (CoV 14.2%), 2.192% (CoV 4.1%) and 39 GPa (CoV 11.3%), respectively. The load–global slip response curves of the composite show an average peak load around 1148 N (CoV 23.0%) and an exploitation ratio versus the textile and the tensile of 0.40 and 0.86, respectively. Even if the preliminary results are encouraging, the performance of FRAAM composites would be positively affected by an increase of the dimensional stability of the matrix.
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15
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Campos Teixeira AH, Soares Junior PRR, Silva TH, Barreto RR, da Silva Bezerra AC. Low-Carbon Concrete Based on Binary Biomass Ash-Silica Fume Binder to Produce Eco-Friendly Paving Blocks. MATERIALS 2020; 13:ma13071534. [PMID: 32230741 PMCID: PMC7178270 DOI: 10.3390/ma13071534] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 03/22/2020] [Accepted: 03/25/2020] [Indexed: 01/07/2023]
Abstract
The civil construction industry consumes huge amounts of raw materials and energy, especially infrastructure. Thus, the use of eco-friendly materials is indispensable to promote sustainable development. In this context, the present work investigated low-carbon concrete to produce eco-friendly paving blocks. The binder was defined according to two approaches. In the first, a binary binder developed with eucalyptus biomass ash (EBA) and silica fume (SF) was used, in total replacement for Portland cement. In the second, the mixture of residues was used as a precursor in alkali-activation reactions, forming alkali-activated binder. The experimental approach was carried out using five different mixtures, obtained by varying the amount of water or sodium hydroxide solution. The characterization of this new material was carried out using compressive strength, expandability, water absorption, deep abrasion, microstructural investigation, and organic matter degradation potential. The results showed that the EBA-SF system has a performance compatible with Portland cement when used as an alternative binder, in addition to functioning as a precursor to alkali-activated concrete. The blocks produced degraded organic matter, and this degradation is more intense with the incidence of UV. In this way, the EBA-SF binder can be successfully used for the manufacture of ecological paving blocks with low carbon emissions.
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Affiliation(s)
- André Henrique Campos Teixeira
- Department of Transports Engineering, Federal Centre for Technological Education of Minas Gerais, Belo Horizonte 30421-169, Brasil;
| | - Paulo Roberto Ribeiro Soares Junior
- Department of Materials Engineering, Federal Centre for Technological Education of Minas Gerais, Belo Horizonte 30421-169, MG, Brazil; (P.R.R.S.J.); (T.H.S.); (R.R.B.)
| | - Thiago Henrique Silva
- Department of Materials Engineering, Federal Centre for Technological Education of Minas Gerais, Belo Horizonte 30421-169, MG, Brazil; (P.R.R.S.J.); (T.H.S.); (R.R.B.)
| | - Richard Rodrigues Barreto
- Department of Materials Engineering, Federal Centre for Technological Education of Minas Gerais, Belo Horizonte 30421-169, MG, Brazil; (P.R.R.S.J.); (T.H.S.); (R.R.B.)
| | - Augusto Cesar da Silva Bezerra
- Department of Transports Engineering, Federal Centre for Technological Education of Minas Gerais, Belo Horizonte 30421-169, Brasil;
- Correspondence: ; Tel.: +55-31-3319-7119
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16
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Petrella A, Di Mundo R, Notarnicola M. Recycled Expanded Polystyrene as Lightweight Aggregate for Environmentally Sustainable Cement Conglomerates. MATERIALS (BASEL, SWITZERLAND) 2020; 13:E988. [PMID: 32098376 PMCID: PMC7078601 DOI: 10.3390/ma13040988] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 02/14/2020] [Accepted: 02/20/2020] [Indexed: 11/16/2022]
Abstract
In the present work the rheological, thermo-mechanical, microstructural, and wetting characteristics of cement mortars with recycled expanded polystyrene (EPS) were analyzed. The samples were prepared after partial/total replacement of the conventional sand aggregate with EPS having different grain size and size distribution. Lightness and thermal insulation were relevant features for all the bare EPS composites, despite the mechanical strengths. Specifically, EPS based mortars were characterized by higher thermal insulation with respect to the sand reference due to the lower specific mass of the specimens mainly associated with the low density of the aggregates and also to the spaces at the EPS/cement paste interfaces. Interesting results in terms of low thermal conductivity and high mechanical resistances were obtained in the case of sand-EPS mixtures although characterized by only 50% in volume of the organic aggregate. Moreover, sand-based mortars showed hydrophilicity (low WCA) and high water penetration, whereas the presence of EPS in the cement composites led to a reduction of the absorption of water especially on the bulk of the composites. Specifically, mortars with EPS in the 2-4 mm and 4-6 mm bead size range showed the best results in term of hydrophobicity (high WCA) and no water penetration in the inner surface, due to low surface energy of the organic aggregate together with a good particle distribution. This was indicative of cohesion between the ligand and the polystyrene as observed in the microstructural detections. Such a property is likely to be correlated to the observed good workability of this type of mortar and to its low tendency to segregation compared to the other EPS containing specimens. These lightweight thermo-insulating composites can be considered environmentally sustainable materials because they are prepared with no pre-treated secondary raw materials and can be used for indoor applications.
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Affiliation(s)
- Andrea Petrella
- Dipartimento di Ingegneria Civile, Ambientale, Edile, del Territorio e di Chimica, Politecnico di Bari, Via E. Orabona, 4, 70125 Bari, Italy; (R.D.M.); (M.N.)
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17
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Pozzolanic Activity of Zeolites: The Role of Si/Al Ratio. MATERIALS 2019; 12:ma12244231. [PMID: 31861105 PMCID: PMC6947560 DOI: 10.3390/ma12244231] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 12/09/2019] [Accepted: 12/13/2019] [Indexed: 12/02/2022]
Abstract
A great challenge of research is the utilization of natural or synthetic zeolites, in place of natural pozzolans, for manufacturing blended cements. The difficulties of interpretation of the pozzolanic behavior of natural zeolite-rich materials and the role played by their nature and composition can be overcome by studying more simple systems, such as pure synthetic zeolites. This study aims at investigating the pozzolanic ability of isostructural zeolites with different framework compositions, such as three sodium zeolites of the faujasite (FAU) framework type: LSX, X, and Y. The pozzolanic activity has been estimated by thermogravimetry and X-ray diffraction analysis. The overall outcome of the investigation is that the zeolite structure affects its pozzolanic activity, as zeolites with similar framework densities exhibit distinct abilities to fix lime. Moreover, the framework composition is effective either from a kinetic point of view or on the total amount of fixed lime. Zeolite X appears to possess the best average features.
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18
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Hybrid Geopolymeric Foams for the Removal of Metallic Ions from Aqueous Waste Solutions. MATERIALS 2019; 12:ma12244091. [PMID: 31817858 PMCID: PMC6947350 DOI: 10.3390/ma12244091] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 11/26/2019] [Accepted: 12/04/2019] [Indexed: 11/18/2022]
Abstract
For the first time, hybrid organic–inorganic geopolymeric foams were successfully used as monolithic adsorbents for the removal of metallic ions pollutants from wastewaters. The foams were realized by the in situ foaming of a hybrid geopolymer obtained by a reaction of metakaolin and polysiloxane oligomers under strong alkaline conditions and then cured at room temperature. In this way, porous materials with densities ranging from 0.4 to 0.7 g/cm3 and showing good mechanical properties were produced. With the aim of producing self-standing monolithic adsorbents for the removal of metallic ions pollutants from wastewaters, these porous hybrid geopolymers were subjected to a washing pretreatment with ultrapure water, dried, and then used for absorption tests by dipping them into an aqueous solution with an initial concentration of 20 ppm of Pb2+, Cd2+, Cu2+, and Zn2+ ions. Preliminary results indicated that all the tested materials are effective in the adsorption of the tested metal ions and do not release the removed metal ions upon sinking in ultrapure water, even for a very long time. Interestingly, compressive strength tests performed before and after the washing treatments show that the foamed samples remain intact and maintain their physical–mechanical characteristics, suggesting that these kinds of materials are promising candidates for the production of self-standing, monolithic adsorbent substrates that can be easily collected when exhausted, which is a major advantage in comparison with the use of powdered adsorbents. Moreover, since these materials can be obtained by a simple and versatile experimental procedure, they could be easily shaped or directly foamed into precast molds to be used in packed beds as membranes.
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Petrella A, Di Mundo R, De Gisi S, Todaro F, Labianca C, Notarnicola M. Environmentally Sustainable Cement Composites Based on End-of-Life Tyre Rubber and Recycled Waste Porous Glass. MATERIALS (BASEL, SWITZERLAND) 2019; 12:E3289. [PMID: 31658637 PMCID: PMC6829454 DOI: 10.3390/ma12203289] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 10/01/2019] [Accepted: 10/08/2019] [Indexed: 11/16/2022]
Abstract
In this paper, environmentally sustainable cement mortars were prepared with end-of-life tyre rubber (TR) and recycled waste porous glass (PG) as aggregates in order to obtain lightweight products characterized by renewable and not-pretreated materials specifically for indoor applications. The secondary raw materials were added as partial and/or total replacement of the conventional sand aggregate. The resulting lightweight specimens were characterized by rheological, mechanical, thermal, microstructural and wettability tests. Fine tyre rubber aggregates affected the cohesiveness of the composites, as opposite to coarse tyre rubber and porous glass. The flexural and the compressive strengths of the porous glass samples were higher than the tyre rubber samples because of the higher stiffness and good adhesion of the glass to the cement paste as observed by microstructural observations. On the contrary, an unfavorable adhesion of the tyre aggregates to the cement paste was observed, together with discrete cracks after failure without separation of the two parts of the specimens. The latter result can explain the best results obtained by tyre rubber mortars in the case of impact compression tests where the super-elastic properties of the elastomeric material were evidenced by a deep groove before complete failure. Moreover, the thermal conductivity decrease of the lightweight porous TR and PG composites was in the range of ~80-90% with respect to the sand-based samples, which suggests that they can be used as plasters and masonries, and, in the case of tyre rubber specimens, outside applications are not excluded as observed from the wettability tests.
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Affiliation(s)
- Andrea Petrella
- Dipartimento di Ingegneria Civile, Ambientale, Edile, del Territorio e di Chimica, Politecnico di Bari, Via E. Orabona 4, 70125 Bari, Italy.
| | - Rosa Di Mundo
- Dipartimento di Ingegneria Civile, Ambientale, Edile, del Territorio e di Chimica, Politecnico di Bari, Via E. Orabona 4, 70125 Bari, Italy.
| | - Sabino De Gisi
- Dipartimento di Ingegneria Civile, Ambientale, Edile, del Territorio e di Chimica, Politecnico di Bari, Via E. Orabona 4, 70125 Bari, Italy.
| | - Francesco Todaro
- Dipartimento di Ingegneria Civile, Ambientale, Edile, del Territorio e di Chimica, Politecnico di Bari, Via E. Orabona 4, 70125 Bari, Italy.
| | - Claudia Labianca
- Dipartimento di Ingegneria Civile, Ambientale, Edile, del Territorio e di Chimica, Politecnico di Bari, Via E. Orabona 4, 70125 Bari, Italy.
| | - Michele Notarnicola
- Dipartimento di Ingegneria Civile, Ambientale, Edile, del Territorio e di Chimica, Politecnico di Bari, Via E. Orabona 4, 70125 Bari, Italy.
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20
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Effects of Red Mud Addition in the Microstructure, Durability and Mechanical Performance of Cement Mortars. APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app9050984] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Recently, there has been a great effort to incorporate industrial waste into cement-based materials to reach a more sustainable cement industry. In this regard, the Bayer process of obtaining alumina from bauxite generates huge amounts of waste called red mud. Few research articles have pointed out the possibility that red mud has pozzolanic activity. In view of that, the objective of this research is to analyse the short-term effects in the pore structure, mechanical performance and durability of mortars which incorporate up to 20% of red mud as a clinker replacement. As a reference, ordinary Portland cement and fly ash Portland cement mortars were also studied. The microstructure was characterised through mercury intrusion porosimetry and non-destructive impedance spectroscopy, which has not previously been used for studying the pore network evolution of red mud cement-based materials. The possible pozzolanic activity of red mud has been checked using differential scanning calorimetry. The non-steady state chloride migration coefficient and the mechanical properties were studied too. According to the results obtained, the addition of red mud entailed a greater microstructure refinement of the mortar, did not worsen the resistance against chloride ingress and reduced the compressive strength compared to control binders.
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21
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Petrella A, Spasiano D, Rizzi V, Cosma P, Race M, De Vietro N. Thermodynamic and kinetic investigation of heavy metals sorption in packed bed columns by recycled lignocellulosic materials from olive oil production. CHEM ENG COMMUN 2019. [DOI: 10.1080/00986445.2019.1574768] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Andrea Petrella
- Dipartimento di Ingegneria Civile, Ambientale, Edile, del Territorio e di Chimica, Politecnico di Bari, Bari, Italy
| | - Danilo Spasiano
- Dipartimento di Ingegneria Civile, Ambientale, Edile, del Territorio e di Chimica, Politecnico di Bari, Bari, Italy
| | - Vito Rizzi
- Dipartimento di Chimica, Università di Bari, Bari, Italy
| | - Pinalysa Cosma
- Dipartimento di Chimica, Università di Bari, Bari, Italy
| | - Marco Race
- Dipartimento di Ingegneria Civile e Meccanica, Università di Cassino e del Lazio Meridionale, Cassino, Italy
| | - Nicoletta De Vietro
- Istituto di Nanotecnologia (Nanotec), Consiglio Nazionale delle Ricerche (CNR), c/o Dipartimento di Chimica, Università degli Studi di Bari “Aldo Moro”, Bari, Italy
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Singh R, Kumar R, Farina I, Colangelo F, Feo L, Fraternali F. Multi-Material Additive Manufacturing of Sustainable Innovative Materials and Structures. Polymers (Basel) 2019; 11:E62. [PMID: 30960046 PMCID: PMC6401995 DOI: 10.3390/polym11010062] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Revised: 12/24/2018] [Accepted: 12/27/2018] [Indexed: 11/21/2022] Open
Abstract
This paper highlights the multi-material additive manufacturing (AM) route for manufacturing of innovative materials and structures. Three different recycled thermoplastics, namely acrylonitrile butadiene styrene (ABS), polylactic acid (PLA), and high impact polystyrene (HIPS) (with different Young's modulus, glass transition temperature, rheological properties), have been selected (as a case study) for multi-material AM. The functional prototypes have been printed on fused deposition modelling (FDM) setup as tensile specimens (as per ASTM D638 type-IV standard) with different combinations of top, middle, and bottom layers (of ABS/PLA/HIPS), at different printing speed and infill percentage density. The specimens were subjected to thermal (glass transition temperature and heat capacity) and mechanical testing (peak load, peak strength, peak elongation, percentage elongation at peak, and Young's modulus) to ascertain their suitability in load-bearing structures, and the fabrication of functional prototypes of mechanical meta-materials. The results have been supported by photomicrographs to observe the microstructure of the analyzed multi-materials.
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Affiliation(s)
- Rupinder Singh
- Department of Production Engineering, Guru Nanak Dev Engineering College, Ludhiana 141006, India.
| | - Ranvijay Kumar
- Department of Production Engineering, Guru Nanak Dev Engineering College, Ludhiana 141006, India.
| | - Ilenia Farina
- Department of Engineering, University of Naples Parthenope, 80143 Naples, Italy.
| | - Francesco Colangelo
- Department of Engineering, University of Naples Parthenope, 80143 Naples, Italy.
| | - Luciano Feo
- Department of Civil Engineering, University of Salerno, 84084 Fisciano (SA), Italy.
| | - Fernando Fraternali
- Department of Civil Engineering, University of Salerno, 84084 Fisciano (SA), Italy.
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Porous Waste Glass for Lead Removal in Packed Bed Columns and Reuse in Cement Conglomerates. MATERIALS 2018; 12:ma12010094. [PMID: 30597857 PMCID: PMC6337151 DOI: 10.3390/ma12010094] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 12/17/2018] [Accepted: 12/24/2018] [Indexed: 12/23/2022]
Abstract
A porous waste glass (RWPG = recycled waste porous glass) was used in wastewater treatments for the removal of lead ions from single, binary, and ternary metal solutions (with cadmium and nickel ions). Experiments were performed in columns (30 cm3, 10 g) filled with 0.5–1 mm beads till complete glass exhaustion (breakthrough). In the case of single and binary solutions, the columns were percolated at 0.2 Lh−1 (2 mg Me+2 L−1); in the case of ternary solutions, the columns were percolated at 0.15–0.4 Lh−1 (2 mg Me2+ L−1) and with 2–5 mg Me2+ L−1 influent concentration (0.2 Lh−1). Lead ions were removed mainly by ion exchange and also by adsorption. From a kinetic point of view, the rate controlling step of the process was the interdiffusion of the lead ions in the Nernst stationary liquid film around the sorbent. The uptake of the metals and the glass selectivity were confirmed by Energy Dispersive X-ray spectroscopy (EDX) analysis. After lead retention process, glass beads were reused as lightweight aggregates for thermal insulating and environmental safe mortars.
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Abstract
Coffee silverskin (CS), the main solid waste produced from the coffee industry, has efficiently been used as adsorbent material to remove potential toxic metals (PTMs). In order to assess its suitability in water remediation, kinetic adsorption experiments of Cu2+, Zn2+, and Ni2+ ions from wastewater were carried out and the adsorption performance of the waste material was compared with that of another well-known waste from coffee industry, spent coffee grounds (SCG). By using CS as sorbent material, ion removal follows the order Cu2+ > Zn2+ > Ni2+ with the adsorption equilibrium occurring after about 20 min. The adsorption efficiency of Ni2+ ions is the same for both investigated materials, while Cu2+ and Zn2+ ions are removed to a lesser extent by using CS. Equilibrium-adsorption data were analyzed using two different isotherm models (Langmuir and Freundlich), demonstrating that monolayer-type adsorption occurs on both CS and SCG surfaces. The overall results support the use of coffee silverskin as a new inexpensive adsorbent material for PTMs from wastewater.
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