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Lăzărescu AV, Hegyi A, Csapai A, Popa F. The Influence of Different Aggregates on the Physico-Mechanical Performance of Alkali-Activated Geopolymer Composites Produced Using Romanian Fly Ash. MATERIALS (BASEL, SWITZERLAND) 2024; 17:485. [PMID: 38276424 PMCID: PMC10820525 DOI: 10.3390/ma17020485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 01/11/2024] [Accepted: 01/17/2024] [Indexed: 01/27/2024]
Abstract
In light of the urgent need to develop environmentally friendly materials that, at some point, will allow the reduction of concrete and, consequently, cement consumption-while at the same time allowing the reuse of waste and industrial by-products-alkali-activated fly ash (AAFA) geopolymer composite emerges as a material of great interest. The aim of this study was to investigate the physico-mechanical performance of composites based on AAFA binders and the effect of different types of aggregates on these properties. The experimental results indicate variations in flexural and compressive strength, which are influenced both by the nature and particle size distribution of aggregates and the binder-to-aggregate ratio. The analysis of the samples highlighted changes in porosity, both in distribution and pore size, depending on the nature of the aggregates. This supports the evolution of physico-mechanical performance indicators.
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Affiliation(s)
| | - Andreea Hegyi
- NIRD URBAN-INCERC Cluj-Napoca Branch, 117 Calea Florești, 400524 Cluj-Napoca, Romania;
- Faculty of Materials and Environmental Engineering, Technical University of Cluj-Napoca, 103-105 Muncii Boulevard, 400641 Cluj-Napoca, Romania;
| | - Alexandra Csapai
- NIRD URBAN-INCERC Cluj-Napoca Branch, 117 Calea Florești, 400524 Cluj-Napoca, Romania;
- Faculty of Materials and Environmental Engineering, Technical University of Cluj-Napoca, 103-105 Muncii Boulevard, 400641 Cluj-Napoca, Romania;
| | - Florin Popa
- Faculty of Materials and Environmental Engineering, Technical University of Cluj-Napoca, 103-105 Muncii Boulevard, 400641 Cluj-Napoca, Romania;
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Turhan Ş, Jamasali YD. Evaluation of radiological health risk caused by the use of fly ash in cement and concrete production and its storage. INTERNATIONAL JOURNAL OF ENVIRONMENTAL HEALTH RESEARCH 2024:1-16. [PMID: 38171026 DOI: 10.1080/09603123.2023.2301051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 12/27/2023] [Indexed: 01/05/2024]
Abstract
As a result of firing pulverized coal in thermal power plants, enormous amounts of fly ash (FA) are produced as industrial waste. The release into the atmosphere and storage of this industrial waste remains one of the major environmental problems that threaten human health by contributing to air, water, and soil pollution. The recovery and reuse of FA in the construction industry is the only economic solution to the existing problem. In this study, the potential radiological risk caused by the usage of FA in concrete and cement production as a main component and its storage in landfill sites was evaluated for people and works by estimating radiological parameters (activity concentration and alpha index, annual effective doses, and the corresponding excess lifetime cancer risks) based on activity concentrations of terrestrial radionuclides in FA. Also, the radiological risk to the workers working in the FA landfill site was evaluated using the Residual Radioactivity Onsite 7.2 code. The average activity concentrations of terrestrial radionuclides in FA samples from the Tunçbilek lignite coal-fired thermal power plant at Kütahya province of Turkey were measured as 417, 156 and 454 Bq kg-1 for 226Ra, 232Th and 40K, respectively. When using up to 35% by mass of FA in cement and concrete, the average values of the radiological parameters revealed that they were within the recommended safety limits. However, code estimations showed that a regular worker in FA storage would be exposed to a total effective dose rate greater than 3 mSv y-1.
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Affiliation(s)
- Şeref Turhan
- Department of Physics, Faculty of Science, Kastamonu University, Kastamonu, Türkiye
| | - Yusof-den Jamasali
- Department of Physics, Faculty of Science, Kastamonu University, Kastamonu, Türkiye
- Department of Physics, College of Natural Sciences and Mathematics, Mindanao State University, Marawı, Philippines
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Laila LR, Karmegam A, Avudaiappan S, Flores EIS. Microstructure and Water Retention Kinetics in Autogenous Cured Self-Compacting Concrete Blends Using Super Absorbent Polymer. Polymers (Basel) 2023; 15:3720. [PMID: 37765575 PMCID: PMC10536232 DOI: 10.3390/polym15183720] [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: 08/03/2023] [Revised: 08/21/2023] [Accepted: 08/22/2023] [Indexed: 09/29/2023] Open
Abstract
This research aimed to determine how a super absorbent polymer affects the microstructural characteristics and water retention kinetics of a new composite made by substituting granite pulver (GP) and fly ash (FA) for cement. Understanding the mechanics of water movement is crucial for comprehending the effectiveness of autogenous curing. Several experiments were conducted to analyze the water mitigation kinetics of super absorbent polymer (SAP) in the hydrating cement paste of autogenous cured self-compacting concrete (GP-ACSSC) mixtures. In the first hours following casting, water sorptivity, water retention, and hydration tests were carried out. The effects of various concentrations of SAP and GP, which was utilized as an alternative cement for the production of sustainable concrete that leads to reduction in carbon footprint, on the autogenous cured self-compacting concrete with reference to the abovementioned properties were explored. The investigation showed that releasing the curing water at a young age, even around the beginning of hydration, allowed homogenous and almost immediate distribution of water across the full cured paste volume, which improved the water retention kinetics. Compared to the control mixtures, the addition of SAP up to 0.6% and the substitution of cement with GP up to 15% had favorable impacts on all water kinetics parameters.
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Affiliation(s)
- Lija Rajamony Laila
- Department of Civil Engineering, KCG College of Technology, Chennai 600097, India
| | - Aarthi Karmegam
- Department of Civil Engineering, Government College of Engineering, Bodinayakkanur 625582, India
| | - Siva Avudaiappan
- Departamento de Ingeniería Civil, Universidad de Concepción, Concepción 4070386, Chile
- Centro Nacional de Excelencia para la Industria de la Madera (CENAMAD), Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, Santiago 8330024, Chile
| | - Erick I Saavedra Flores
- Departamento de Ingeniería en Obras Civiles, Universidad de Santiago de Chile, Av. Ecuador 3659, Estación Central, Santiago 9170022, Chile
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Hegyi A, Lăzărescu AV, Ciobanu AA, Ionescu BA, Grebenişan E, Chira M, Florean C, Vermeşan H, Stoian V. Study on the Possibilities of Developing Cementitious or Geopolymer Composite Materials with Specific Performances by Exploiting the Photocatalytic Properties of TiO 2 Nanoparticles. MATERIALS (BASEL, SWITZERLAND) 2023; 16:ma16103741. [PMID: 37241366 DOI: 10.3390/ma16103741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 05/06/2023] [Accepted: 05/11/2023] [Indexed: 05/28/2023]
Abstract
Starting from the context of the principles of Sustainable Development and Circular Economy concepts, the paper presents a synthesis of research in the field of the development of materials of interest, such as cementitious composites or alkali-activated geopolymers. Based on the reviewed literature, the influence of compositional or technological factors on the physical-mechanical performance, self-healing capacity and biocidal capacity obtained was analyzed. The inclusion of TiO2 nanoparticles in the matrix increase the performances of cementitious composites, producing a self-cleaning capacity and an anti-microbial biocidal mechanism. As an alternative, the self-cleaning capacity can be achieved through geopolymerization, which provides a similar biocidal mechanism. The results of the research carried out indicate the real and growing interest for the development of these materials but also the existence of some elements still controversial or insufficiently analyzed, therefore concluding the need for further research in these areas. The scientific contribution of this study consists of bringing together two apparently distinct research directions in order to identify convergent points, to create a favorable framework for the development of an area of research little addressed so far, namely, the development of innovative building materials by combining improved performance with the possibility of reducing environmental impact, awareness and implementation of the concept of a Circular Economy.
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Affiliation(s)
- Andreea Hegyi
- NIRD URBAN-INCERC Cluj-Napoca Branch, 117 Calea Floresti, 400524 Cluj-Napoca, Romania
| | | | | | | | - Elvira Grebenişan
- NIRD URBAN-INCERC Cluj-Napoca Branch, 117 Calea Floresti, 400524 Cluj-Napoca, Romania
| | - Mihail Chira
- NIRD URBAN-INCERC Cluj-Napoca Branch, 117 Calea Floresti, 400524 Cluj-Napoca, Romania
| | - Carmen Florean
- NIRD URBAN-INCERC Cluj-Napoca Branch, 117 Calea Floresti, 400524 Cluj-Napoca, Romania
- NIRD URBAN-INCERC Iaşi Branch, 6 Anton Şesan Street, 700048 Iaşi, Romania
| | - Horaţiu Vermeşan
- Faculty of Materials and Environmental Engineering, Technical University of Cluj-Napoca, 103-105 Muncii Boulevard, 400641 Cluj-Napoca, Romania
| | - Vlad Stoian
- Department of Microbiology, Facutly of Agriculture, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 3-5 Calea Mănăştur, 400372 Cluj-Napoca, Romania
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Arunachalam KP, Avudaiappan S, Flores EIS, Parra PF. Experimental Study on the Mechanical Properties and Microstructures of Cenosphere Concrete. MATERIALS (BASEL, SWITZERLAND) 2023; 16:ma16093518. [PMID: 37176400 PMCID: PMC10179900 DOI: 10.3390/ma16093518] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Revised: 04/14/2023] [Accepted: 04/19/2023] [Indexed: 05/15/2023]
Abstract
The most valuable components of coal fly ash are cenospheres. Cenospheres are hollow spherical particles produced during the coal-burning processes. As a result of their excellent characteristics, such as high workability, high heat resistance, low bulk density, and high strength, cenospheres can be used in the manufacturing of lightweight cement concrete. The research efforts and outcomes are to produce long-lasting cement-based lightweight concrete (LWC) composites with good mechanical properties. The novelty of this investigation is to determine the cement concrete strength when silica fume (SF) and cenospheres (CS) were used as a replacement for cement. Throughout the experiments, a consistent substitution of 12% silica fume was incorporated into cement mass. Silica is used as a micro filler and pozzolanic reactant to strengthen concrete. The concrete mixtures were tested to ensure they met the requirements of the lightweight concrete in terms of their mechanical, physical, and durability qualities. According to the findings, lightweight concrete standards were met, and environmental sustainability was improved with the use of these mix proportions. Concrete specimen's self-weight decreases by 35% with 30% cenosphere as a replacement. The micrograph shows the lack of portlandite is filled by mullite and other alumino silicates from the cenosphere. In order to achieve sustainability in concrete manufacturing, these mixtures can be suggested for the making of structural LWC that makes use of a large volume of industrial waste while conserving cement and natural resources.
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Affiliation(s)
- Krishna Prakash Arunachalam
- Department of Civil Engineering, University College of Engineering Nagercoil, Anna University, Nagercoil 629004, India
| | - Siva Avudaiappan
- Departamento de Ingeniería Civil, Universidad de Concepción, Concepción 4030000, Chile
- Centro Nacional de Excelencia para la Industria de la Madera (CENAMAD), Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, Santiago 1030000, Chile
- Department of Physiology, Saveetha Dental College and Hospitals, SIMATS, Chennai 600077, India
| | - Erick I Saavedra Flores
- Departamento de Ingeniería en Obras Civiles, Universidad de Santiago de Chile, Av. Ecuador 3659, Estación Central, Santiago 9170022, Chile
| | - Pablo Fernando Parra
- Faculty of Engineering and Sciences, Universidad Adolfo Ibáñez, Santiago 7941169, Chile
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Caño A, Suárez-Navarro JA, Puertas F, Fernández-Jiménez A, Alonso MDM. New Approach to Determine the Activity Concentration Index in Cements, Fly Ashes, and Slags on the Basis of Their Chemical Composition. MATERIALS (BASEL, SWITZERLAND) 2023; 16:2677. [PMID: 37048970 PMCID: PMC10095990 DOI: 10.3390/ma16072677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 03/23/2023] [Accepted: 03/26/2023] [Indexed: 06/19/2023]
Abstract
The manufacture of Portland cement entails high energy and environmental costs, and various solutions have been implemented in recent years to mitigate this negative impact. These solutions include improvements in the manufacture of cement clinker or the use of supplementary cementitious materials (SCMs), such as fly ash (FA) or slag as a replacement for a portion of the clinker in cement. The incorporation of these SCMs in cement may increase its radiological content as they are naturally occurring radioactive materials (NORMs). The Activity Concentration Index (ACI) is a screening tool established in the European EURATOM Directive 2013/59 to determine the radiation protection suitability of a final construction material. The ACI is determined by the activity concentrations of 226Ra, 232Th and 40K, usually determined by gamma spectrometry. The methodology of gamma spectrometry is accurate and appropriate, but this technique is not available in all laboratories. For this reason, and taking into account that there is a relationship between the chemical and radiological composition of these building materials, a new approach is proposed to determine the radiological content of these materials from a chemical analysis such as X-ray fluorescence (XRF). In this paper, principal component analysis (PCA) is used to establish the relationships between the chemical composition and radiological content of cements, FAs, and slags of different natures. Through PCA it was possible to group the cements based on two variables: CaO content and Fe2O3-Al2O3-TiO2 content. A lower correlation was observed for the FAs and slags, as the sample scores were centered around the origin of the coordinates and showed greater dispersion than the cements. The clusters obtained in the HJ-Biplots allowed the determination, using multiple regression, of models relating the activity concentration of 226Ra, 232Th (212Pb), and 40K to the oxide percentages obtained for the three matrices studied. The models were validated using five cements, one FA and one slag with relative percentage deviations (RSD(%)) equal to or less than 30% for 89% of the activity concentrations and 100% of the ACI determined.
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Affiliation(s)
- Andrés Caño
- Eduardo Torroja Institute for Construction Sciences (IETcc-CSIC), 28033 Madrid, Spain
| | - José Antonio Suárez-Navarro
- Environmental Radioactivity and Radiological Monitoring Unit (URAyVR), Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Avda Complutense, 40, 28040 Madrid, Spain
| | - Francisca Puertas
- Eduardo Torroja Institute for Construction Sciences (IETcc-CSIC), 28033 Madrid, Spain
| | - Ana Fernández-Jiménez
- Eduardo Torroja Institute for Construction Sciences (IETcc-CSIC), 28033 Madrid, Spain
| | - María del Mar Alonso
- Eduardo Torroja Institute for Construction Sciences (IETcc-CSIC), 28033 Madrid, Spain
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Baskar P, Annadurai S, Sekar K, Prabakaran M. A Review on Fresh, Hardened, and Microstructural Properties of Fibre-Reinforced Geopolymer Concrete. Polymers (Basel) 2023; 15:polym15061484. [PMID: 36987261 PMCID: PMC10051752 DOI: 10.3390/polym15061484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 02/17/2023] [Accepted: 03/08/2023] [Indexed: 03/19/2023] Open
Abstract
Alternative eco-friendly and sustainable construction methods are being developed to address growing infrastructure demands, which is a promising field of study. The development of substitute concrete binders is required to alleviate the environmental consequences of Portland cement. Geopolymers are very promising low-carbon, cement-free composite materials with superior mechanical and serviceability properties, compared to Ordinary Portland Cement (OPC) based construction materials. These quasi-brittle inorganic composites, which employ an “alkali activating solution” as a binder agent and industrial waste with greater alumina and silica content as its base material, can have their ductility enhanced by utilising the proper reinforcing elements, ideally “fibres”. By analysing prior investigations, this paper explains and shows that Fibre Reinforced Geopolymer Concrete (FRGPC) possesses excellent thermal stability, low weight, and decreased shrinking properties. Thus, it is strongly predicted that fibre-reinforced geopolymers will innovate quickly. This research also discusses the history of FRGPC and its fresh and hardened properties. Lightweight Geopolymer Concrete (GPC) absorption of moisture content and thermomechanical properties formed from Fly ash (FA), Sodium Hydroxide (NaOH), and Sodium Silicate (Na2SiO3) solutions, as well as fibres, are evaluated experimentally and discussed. Additionally, extending fibre measures become advantageous by enhancing the instance’s long-term shrinking performance. Compared to non-fibrous composites, adding more fibre to the composite often strengthens its mechanical properties. The outcome of this review study demonstrates the mechanical features of FRGPC, including density, compressive strength, split tensile strength, and flexural strength, as well as its microstructural properties.
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Affiliation(s)
- Prabu Baskar
- Department of Civil Engineering, Sona College of Technology, Salem 636 005, India
| | - Shalini Annadurai
- Department of Civil Engineering, Sona College of Technology, Salem 636 005, India
| | - Kaviya Sekar
- Department of Civil Engineering, Sona College of Technology, Salem 636 005, India
| | - Mayakrishnan Prabakaran
- Department of Chemistry, Dongguk University, Seoul 04620, Republic of Korea
- Correspondence: or
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Gailitis R, Pakrastins L, Sprince A, Radina L, Sakale G, Miernik K. Different Fiber Reinforcement Effects on Fly Ash-Based Geopolymer Long-Term Deflection in Three-Point Bending and Microstructure. MATERIALS (BASEL, SWITZERLAND) 2022; 15:8512. [PMID: 36500007 PMCID: PMC9736236 DOI: 10.3390/ma15238512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 11/23/2022] [Accepted: 11/24/2022] [Indexed: 06/17/2023]
Abstract
This study investigated the effect of a low amount of polyvinyl alcohol (PVA) and steel fiber reinforcement on fly ash-based geopolymer composite long-term deflection and its microstructure. For testing purposes, specimens with different amounts and types of fiber reinforcement as well as plain (reference) were prepared. The long-term deflection test was performed by loading specimens with 40% of the ultimate flexural strength. A microstructure analysis was performed using polished section specimens, and images were acquired at 25-times magnification on a scanning electron microscope. The results of the flexural strength test show that all geopolymer composites with fiber reinforcement have lower flexural strength than plain geopolymer composites. The long-term deflection tests show that the highest deflections exhibit 1% PVA fiber-reinforced specimens. The lowest amount of deflection is for 1% steel fiber-reinforced specimens. Specific creep shows similar results to plain, and 1% steel fiber-reinforced specimens, while 1% PVA and 0.5% PVA/0.5% steel fiber-reinforced specimen exhibits the same properties. The quantitative microanalysis of the polished section further confirms the deflection results. Specimens with 1% PVA fiber reinforcement have significantly higher porosity than all other specimens. They are followed by plain specimens and 1% steel fiber, and 0.5% PVA/0.5 steel fiber-reinforced specimens have almost the same porosity level.
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Affiliation(s)
- Rihards Gailitis
- Institute of Structural Engineering, Riga Technical University, Kipsalas 6A, LV-1048 Riga, Latvia
| | - Leonids Pakrastins
- Institute of Structural Engineering, Riga Technical University, Kipsalas 6A, LV-1048 Riga, Latvia
| | - Andina Sprince
- Institute of Structural Engineering, Riga Technical University, Kipsalas 6A, LV-1048 Riga, Latvia
| | - Liga Radina
- Institute of Structural Engineering, Riga Technical University, Kipsalas 6A, LV-1048 Riga, Latvia
| | - Gita Sakale
- Institute of Structural Engineering, Riga Technical University, Kipsalas 6A, LV-1048 Riga, Latvia
| | - Krzysztof Miernik
- Department of Materials Engineering, Faculty of Material Engineering and Physics, Cracow University of Technology, Jana Pawła II 37, 31-864 Cracow, Poland
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Pavlíková M, Rovnaníková P, Záleská M, Pavlík Z. Diatomaceous Earth-Lightweight Pozzolanic Admixtures for Repair Mortars-Complex Chemical and Physical Assessment. MATERIALS (BASEL, SWITZERLAND) 2022; 15:ma15196881. [PMID: 36234222 PMCID: PMC9573052 DOI: 10.3390/ma15196881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 09/29/2022] [Accepted: 09/29/2022] [Indexed: 05/10/2023]
Abstract
The presented research is focused on the complex assessment of three different types of diatomaceous earth and evaluation of their ability for application as pozzolana active admixtures applicable in the concrete industry and the production of repair mortars applicable for historical masonry. The comprehensive experimental campaign comprised chemical, mineralogical, microstructural, and physical testing of raw materials, followed by the analyses and characterization of pozzolanic activity, rheology and heat evolution of fresh blended pastes, and testing of macrostructural and mechanical parameters of the hardened 28-days and 90-days samples. The obtained results gave evidence of the different behavior of researched diatomaceous earth when mixed with water and Portland cement. The differences in heat evolution, initial and final setting time, porosity, density, and mechanical parameters were identified based on chemical and phase composition, particle size, specific surface, and morphology of diatomaceous particles. Nevertheless, the researched mineral admixtures yielded a high strength activity index (92.9% to 113.6%), evinced their pozzolanic activity. Three fundamental factors were identified that affect diatomaceous earth's contribution to the mechanical strength of cement blends. These are the filler effect, the pertinent acceleration of OPC hydration, and the pozzolanic reaction of diatomite with Portland cement hydrates. The optimum replacement level of ordinary Portland cement by diatomaceous earth to give maximum long-term strength enhancement is about 10 wt.%., but it might be further enhanced based on the properties of pozzolan.
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Affiliation(s)
- Milena Pavlíková
- Department of Materials Engineering and Chemistry, Faculty of Civil Engineering, Czech Technical University in Prague, Thákurova 7, 166 29 Prague, Czech Republic
- Correspondence: ; Tel.: +420-224-354-688
| | - Pavla Rovnaníková
- Institute of Chemistry, Faculty of Civil Engineering, Brno University of Technology, Žižkova 17, Veveří, 602 00 Brno, Czech Republic
| | - Martina Záleská
- Department of Materials Engineering and Chemistry, Faculty of Civil Engineering, Czech Technical University in Prague, Thákurova 7, 166 29 Prague, Czech Republic
| | - Zbyšek Pavlík
- Department of Materials Engineering and Chemistry, Faculty of Civil Engineering, Czech Technical University in Prague, Thákurova 7, 166 29 Prague, Czech Republic
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Saeed HZ, Saleem MZ, Chua YS, Vatin NI. Research on Structural Performance of Hybrid Ferro Fiber Reinforced Concrete Slabs. MATERIALS (BASEL, SWITZERLAND) 2022; 15:6748. [PMID: 36234089 PMCID: PMC9572473 DOI: 10.3390/ma15196748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 08/13/2022] [Accepted: 08/17/2022] [Indexed: 06/16/2023]
Abstract
Reinforced concrete structures, particularly in cold areas, experience early deterioration due to steel corrosion. Fiber-Reinforced Concrete (FRC) is an emerging construction material and cost-effective substitute for conventional concrete to enhance the durability and resistance against crack development. This article examines the structural performance of hybrid ferro fiber reinforced concrete slabs (mix ratio of mortar 1:2) comprising silica fume, layers of spot-welded mesh and different ratios of polypropylene fibers. The ferrocement slabs are compared with a conventional Reinforced Cement Concrete (RCC) slab (mix ratio of 1:2:4). The experimental work comprised a total of 13 one-way slabs, one control specimen and three groups of ferrocement slabs divided based on different percentages of Poly Propylene Fibers (PPF) corresponding to 0.10%, 0.30% and 0.50% dosage in each group. Furthermore, in each group, the percentage of steel ratio in ferrocement slabs varied between 25% and 100% of the steel area in the reinforced concrete control slab specimen. For evaluating the structural performance, the observation of deflection, stress-strain behavior, cracking load and energy absorption are critical parameters assessed using LVDTs and strain gauges. At the same time, the slabs were tested in flexure mode with third point loading. The experimental results showed that the first cracking load and ultimate deflection for fibrous specimens with 0.5% fiber and 10% silica fume increased by 15.25% and 13.2% compared with the reference RCC control slab. Therefore, by increasing the percentage of PPF and steel wire mesh reinforcement in the ferrocement slab, the post-cracking behavior in terms of deflection properties and energy absorption capacity was substantially enhanced compared to the RCC control slab.
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Affiliation(s)
- Hafiz Zain Saeed
- School of Engineering, Monash University, Jalan Lagoon Selatan, Bandar Sunway 47500, Malaysia
| | - Muhammad Zubair Saleem
- Department of Civil Engineering, University of Engineering and Technology, Taxila 47080, Pakistan
| | - Yie Sue Chua
- School of Engineering, Monash University, Jalan Lagoon Selatan, Bandar Sunway 47500, Malaysia
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11
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Alani AA, Lesovik R, Lesovik V, Fediuk R, Klyuev S, Amran M, Ali M, de Azevedo ARG, Vatin NI. Demolition Waste Potential for Completely Cement-Free Binders. MATERIALS (BASEL, SWITZERLAND) 2022; 15:ma15176018. [PMID: 36079400 PMCID: PMC9457524 DOI: 10.3390/ma15176018] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Revised: 08/19/2022] [Accepted: 08/29/2022] [Indexed: 06/01/2023]
Abstract
Due to renovation and fighting in the world, a huge accumulation of construction and demolition waste is formed. These materials are effectively used as aggregates, but there is very little information about the use of scrap concrete to create cementless binders. The purpose of the work is to be a comprehensive study of the composition and properties of concrete wastes of various fractions with the aim of their rational use as cementless binders. The scientific novelty lies in the fact that the nature of the processes of structure formation of a cementless binder based on sandy fractions of the screening of fragments of destroyed buildings and structures, as a complex polyfunctional system, has been theoretically substantiated and experimentally confirmed. Different percentages of non-hydrated clinker minerals in concrete scrap were determined. In the smallest fraction (less than 0.16 mm), more than 20% of alite and belite are present. Waste of the old cement paste is more susceptible to crushing compared to the large aggregate embedded in it, therefore, particles of the old cement paste and fine aggregate predominate in the finer fractions of the waste. Comprehensive microstructural studies have been carried out on the possibility of using concrete scrap as a completely cementless binder using scanning electron microscopy, X-ray diffraction analysis, and differential thermal analysis. It has been established that for cementless samples prepared from the smallest fractions (less than 0.315 mm), the compressive strength is 1.5-2 times higher than for samples from larger fractions. This is due to the increased content of clinker minerals in their composition. The compressive strength of the cementless binder after 28 days (7.8 MPa), as well as the early compressive strength at the age of 1 day after steaming (5.9 MPa), make it possible to effectively use these materials for enclosing building structures.
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Affiliation(s)
| | - Ruslan Lesovik
- Department of Building Materials Science, Products and Structures, Belgorod State Technological University Named after V.G. Shukhov, 308012 Belgorod, Russia
| | - Valery Lesovik
- Department of Building Materials Science, Products and Structures, Belgorod State Technological University Named after V.G. Shukhov, 308012 Belgorod, Russia
- Central Research and Design Institute of the Ministry of Construction, Housing and Utilities of the Russian Federation, 119331 Moscow, Russia
| | - Roman Fediuk
- Polytechnical Institute, Far Eastern Federal University, 690922 Vladivostok, Russia
- Peter the Great St. Petersburg Polytechnic University, 195251 St. Petersburg, Russia
| | - Sergey Klyuev
- Department of Building Materials Science, Products and Structures, Belgorod State Technological University Named after V.G. Shukhov, 308012 Belgorod, Russia
| | - Mugahed Amran
- Department of Civil Engineering, College of Engineering, Prince Sattam Bin Abdulaziz University, Alkharj 16273, Saudi Arabia
- Department of Civil Engineering, Faculty of Engineering and IT, Amran University, Amran 9677, Yemen
| | - Mujahid Ali
- Department of Civil and Environmental Engineering, Universiti Teknologi PETRONAS, Seri Iskandar 32610, Malaysia
| | - Afonso R. G. de Azevedo
- LECIV—Civil Engineering Laboratory, UENF—State University of the Northern Rio de Janeiro, 2000 Av. Alberto Lamego, Campos dos Goytacazes, Rio de Janeiro 28013-602, Brazil
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Technogenic Fiber Wastes for Optimizing Concrete. MATERIALS 2022; 15:ma15145058. [PMID: 35888529 PMCID: PMC9325013 DOI: 10.3390/ma15145058] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/25/2022] [Revised: 07/15/2022] [Accepted: 07/18/2022] [Indexed: 02/01/2023]
Abstract
A promising method of obtaining mineral fiber fillers for dry building mixtures is the processing of waste that comes from the production of technogenic fibrous materials (TFM). The novelty of the work lies in the fact that, for the first time, basalt production wastes were studied not only as reinforcing components, but also as binder ones involved in concrete structure formation. The purpose of the article is to study the physical and mechanical properties of waste technogenic fibrous materials as additives for optimizing the composition of raw concrete mixes. To assess the possibility of using wastes from the complex processing of TFM that were ground for 5 and 10 min as an active mineral additive to concrete, their chemical, mineralogical, and granulometric compositions, as well as the microstructure and physical and mechanical characteristics of the created concretes, were studied. It is established that the grinding of TFM for 10 min leads to the grinding of not only fibers, but also pellets, the fragments of which are noticeable in the total mass of the substance. The presence of quartz in the amorphous phase of TFM makes it possible to synthesize low-basic calcium silicate hydrates in a targeted manner. At 90 days age, at 10–20% of the content of TFM, the strength indicators increase (above 40 MPa), and at 30% of the additive content, they approach the values of the control composition without additives (above 35 MPa). For all ages, the ratio of flexural and compressive strengths is at the level of 0.2, which characterizes a high reinforcing effect. Analysis of the results suggests the possibility of using waste milled for 10 min as an active mineral additive, as well as to give better formability to the mixture and its micro-reinforcement to obtain fiber-reinforced concrete.
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Recent Trends in Advanced Radiation Shielding Concrete for Construction of Facilities: Materials and Properties. Polymers (Basel) 2022; 14:polym14142830. [PMID: 35890605 PMCID: PMC9316934 DOI: 10.3390/polym14142830] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 06/30/2022] [Accepted: 07/04/2022] [Indexed: 01/21/2023] Open
Abstract
Nuclear energy offers a wide range of applications, which include power generation, X-ray imaging, and non-destructive tests, in many economic sectors. However, such applications come with the risk of harmful radiation, thereby requiring shielding to prevent harmful effects on the surrounding environment and users. Concrete has long been used as part of structures in nuclear power plants, X-ray imaging rooms, and radioactive storage. The direction of recent research is headed toward concrete’s ability in attenuating harmful energy radiated from nuclear sources through various alterations to its composition. Radiation shielding concrete (RSC) is a composite-based concrete that was developed in the last few years with heavy natural aggregates such as magnetite or barites. RSC is deemed a superior alternative to many types of traditional normal concrete in terms of shielding against the harmful radiation, and being economical and moldable. Given the merits of RSCs, this article presents a comprehensive review on the subject, considering the classifications, alternative materials, design additives, and type of heavy aggregates used. This literature review also provides critical reviews on RSC performance in terms of radiation shielding characteristics, mechanical strength, and durability. In addition, this work extensively reviews the trends of development research toward a broad understanding of the application possibilities of RSC as an advanced concrete product for producing a robust and green concrete composite for the construction of radiation shielding facilities as a better solution for protection from sources of radiation. Furthermore, this critical review provides a view of the progress made on RSCs and proposes avenues for future research on this hotspot research topic.
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Chakrawarthi V, Dharmar B, Avudaiappan S, Amran M, Flores ES, Alam MA, Fediuk R, Vatin NI, Rashid RSM. Destructive and Non-Destructive Testing of the Performance of Copper Slag Fiber-Reinforced Concrete. MATERIALS (BASEL, SWITZERLAND) 2022; 15:4536. [PMID: 35806661 PMCID: PMC9267722 DOI: 10.3390/ma15134536] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 06/17/2022] [Accepted: 06/23/2022] [Indexed: 02/01/2023]
Abstract
Concrete technology is adopted worldwide in construction due to its effectiveness, performance, and price benefits. Subsequently, it needs to be an eco-friendly, sustainable, and energy-efficient material. This is achieved by replacing or adding energy-efficient concrete materials from industries, such as ground granulated blast furnace slag, steel slag, fly ash, bottom ash, rice husk ash, etc. Likewise, copper slag is a waste material produced as molten slag from the copper industry, which can be used in concrete production. Copper slag can perform roles similar to pozzolans in the hydration process. This paper extends the comparative study of copper slag concrete with polypropylene fiber (PPF) subjected to destructive and non-destructive testing. Under destructive testing, compressive strength of concrete cubes, compressive strength of mortar cubes, splitting tensile tests on cylindrical specimens, and flexural tests on plain cement concrete were conducted and analysed. Ultrasonic pulse velocity and rebound hammer tests were performed on the samples as per IS13311-Part 1-1992 for non-destructive testing. The 100% replacement of copper slag exhibited a very high workability of 105 mm, while the addition of 0.8% PPF decreased the flowability of the concrete. Hence, the workability of concrete decreases as the fiber content increases. The density of the concrete was found to be increased in the range of 5% to 10%. Furthermore, it was found that, for all volume fractions of fiber, there was no reduction in compressive strength of up to 80% of copper slag concrete compared to control concrete. The 40% copper slag concrete was the best mix proportion for increasing compressive strength. However, for cement mortar applications, 80% copper slag is recommended. The findings of non-destructive testing show that, except for 100% copper slag, all mixes were of good quality compared to other mixes. Linear relationships were developed to predict compressive strength from UPV and rebound hammer test values. This relationship shows better prediction among dependent and independent values. It is concluded that copper slag has a pozzolanic composition, and is compatible with PPF, resulting in good mechanical characteristics.
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Affiliation(s)
- Vijayaprabha Chakrawarthi
- Department of Civil Engineering, Alagappa Chettiar Government College of Engineering and Technology, Karaikudi 630003, India;
| | - Brindha Dharmar
- Department of Civil Engineering, Thiagarajar College of Engineering, Madurai 625015, India;
| | - Siva Avudaiappan
- Departamento de Ingeniería Civil, Universidad de Concepción, Concepción 4030000, Chile
| | - Mugahed Amran
- Department of Civil Engineering, College of Engineering, Prince Sattam Bin Abdulaziz University, Alkharj 16273, Saudi Arabia
- Department of Civil Engineering, Faculty of Engineering and IT, Amran University, Amran 9677, Yemen
| | - Erick Saavedra Flores
- Departamento de Ingeniería en Obras Civiles, University of Santiago of Chile, Av. Ecuador 3659, Santiago 9170201, Chile;
| | - Mohammad Ayaz Alam
- Departamento de Geología, Facultad de Ingeniería, Universidad de Atacama, Avenida Copayapu 485, Copiapó 1531772, Región de Atacama, Chile;
| | - Roman Fediuk
- Polytechnic Institute, Far Eastern Federal University, 690922 Vladivostok, Russia;
- Peter the Great St. Petersburg Polytechnic University, 195251 St. Petersburg, Russia;
| | | | - Raizal S. M. Rashid
- Department of Civil Engineering, Faculty of Engineering, Universiti Putra Malaysia, Serdang 43400, Malaysia;
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Prakash R, Divyah N, Srividhya S, Avudaiappan S, Amran M, Naidu Raman S, Guindos P, Vatin NI, Fediuk R. Effect of Steel Fiber on the Strength and Flexural Characteristics of Coconut Shell Concrete Partially Blended with Fly Ash. MATERIALS 2022; 15:ma15124272. [PMID: 35744338 PMCID: PMC9229043 DOI: 10.3390/ma15124272] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 06/07/2022] [Accepted: 06/15/2022] [Indexed: 02/01/2023]
Abstract
The construction industry relies heavily on concrete as a building material. The coarse aggregate makes up a substantial portion of the volume of concrete. However, the continued exploitation of granite rock for coarse aggregate results in an increase in the future generations’ demand for natural resources. In this investigation, coconut shell was used in the place of conventional aggregate to produce coconut shell lightweight concrete. Class F fly ash was used as a partial substitute for cement to reduce the high cement content of lightweight concrete. The impact of steel fiber addition on the compressive strength and flexural features of sustainable concrete was investigated. A 10% weight replacement of class F fly ash was used in the place of cement. Steel fiber was added at 0.25, 0.5, 0.75, and 1.0% of the concrete volume. The results revealed that the addition of steel fibers enhanced the compressive strength by up to 39%. The addition of steel fiber to reinforced coconut shell concrete beams increased the ultimate moment capacity by 5–14%. Flexural toughness was increased by up to 45%. The span/deflection ratio of all fiber-reinforced coconut shell concrete beams met the IS456 and BS 8110 requirements. Branson’s and the finite element models developed in this study agreed well with the experimental results. As a result, coconut shell concrete with steel fiber could be considered as a viable and environmentally-friendly construction material.
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Affiliation(s)
- Ramaiah Prakash
- Department of Civil Engineering, Alagappa Chettiar Government College of Engineering and Technology, Karaikudi 630001, India
- Correspondence: (R.P.); (M.A.)
| | - Nagarajan Divyah
- Department of Civil Engineering, Government College of Technology, Coimbatore 641013, India;
| | - Sundaresan Srividhya
- Department of Civil Engineering, Varuvan Vadivelan Institute of Technology, Dharmapuri 636703, India;
| | - Siva Avudaiappan
- Departamento de Ingeniería Civil, Universidad de Concepción, Concepción 4070386, Chile;
- Centro Nacional de Excelenciapara la Industria de la Madera (CENAMAD), Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, Santiago 8330024, Chile;
| | - Mugahed Amran
- Department of Civil Engineering, College of Engineering, Prince Sattam Bin Abdulaziz University, Alkharj 16273, Saudi Arabia
- Department of Civil Engineering, Faculty of Engineering and IT, Amran University, Amran 9677, Yemen
- Correspondence: (R.P.); (M.A.)
| | - Sudharshan Naidu Raman
- Civil Engineering Discipline, School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway 47500, Selangor, Malaysia;
| | - Pablo Guindos
- Centro Nacional de Excelenciapara la Industria de la Madera (CENAMAD), Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, Santiago 8330024, Chile;
| | - Nikolai Ivanovich Vatin
- Peter the Great St. Petersburg Polytechnic University, 195251 St. Petersburg, Russia; (N.I.V.); (R.F.)
| | - Roman Fediuk
- Peter the Great St. Petersburg Polytechnic University, 195251 St. Petersburg, Russia; (N.I.V.); (R.F.)
- Polytechnic Institute, Far Eastern Federal University, 690922 Vladivostok, Russia
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Rerkratn A, Prombut S, Kamsri T, Riewruja V, Petchmaneelumka W. A Procedure for Precise Determination and Compensation of Lead-Wire Resistance of a Two-Wire Resistance Temperature Detector. SENSORS 2022; 22:s22114176. [PMID: 35684795 PMCID: PMC9185636 DOI: 10.3390/s22114176] [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: 04/12/2022] [Revised: 05/26/2022] [Accepted: 05/27/2022] [Indexed: 11/29/2022]
Abstract
A procedure for the precise determination and compensation of the lead-wire resistance of a resistance transducer is presented. The proposed technique is suitable for a two-wire resistance transducer, especially the resistance temperature detector (RTD). The proposed procedure provides a technique to compensate for the lead-wire resistance using a three-level pulse signal to excite the RTD via the long lead wire. In addition, the variation in the lead-wire resistance disturbed by the change in the ambient temperature can also be compensated by using the proposed technique. The determination of the lead-wire resistance from the proposed procedure requires a simple computation method performed by a digital signal processing unit. Therefore, the calculation of the RTD resistance and the lead-wire resistance can be achieved without the requirement of a high-speed digital signal processing unit. The proposed procedure is implemented on two platforms to confirm its effectiveness: the LabVIEW computer program and the microcontroller board. Experimental results show that the RTD resistance was accurately acquired, where the measured temperature varied from 0 °C to 300 °C and the lead-wire resistance varied from 0.2 Ω to 20 Ω, corresponding to the length of the 26 American wire gauge (AWG) lead wire from 1.5 m to 150 m. The average power dissipation to the RTD was very low and the self-heating of the RTD was minimized. The measurement error of the RTD resistance observed for pt100 was within ±0.98 Ω or ±0.27 °C when the lead wire of 30 m was placed in an environment with the ambient temperature varying from 30 °C to 70 °C. It is evident that the proposed procedure provided a performance that agreed with the theoretical expectation.
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Affiliation(s)
- Apinai Rerkratn
- School of Engineering, King Mongkut’s Institute of Technology Ladkrabang, Bangkok 10520, Thailand; (A.R.); (S.P.)
| | - Supatsorn Prombut
- School of Engineering, King Mongkut’s Institute of Technology Ladkrabang, Bangkok 10520, Thailand; (A.R.); (S.P.)
| | | | - Vanchai Riewruja
- School of Engineering, King Mongkut’s Institute of Technology Ladkrabang, Bangkok 10520, Thailand; (A.R.); (S.P.)
- Correspondence: (V.R.); (W.P.)
| | - Wandee Petchmaneelumka
- School of Engineering, King Mongkut’s Institute of Technology Ladkrabang, Bangkok 10520, Thailand; (A.R.); (S.P.)
- Correspondence: (V.R.); (W.P.)
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Heat Treatment of Geopolymer Samples Obtained by Varying Concentration of Sodium Hydroxide as Constituent of Alkali Activator. Gels 2022; 8:gels8060333. [PMID: 35735677 PMCID: PMC9222481 DOI: 10.3390/gels8060333] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 05/19/2022] [Accepted: 05/23/2022] [Indexed: 12/04/2022] Open
Abstract
In this paper, raw natural metakaolin (MK, Serbia) clay was used as a starting material for the synthesis of geopolymers for thermal treatment. Metakaolin was obtained by calcination of kaolin at 750 °C for 1 h while geopolymer samples were calcined at 900 °C, which is the key transition temperature. Metakaolin was activated by a solution of NaOH of various concentrations and sodium silicate. During the controlled heat treatment, the geopolymer samples began to melt slightly and coagulate locally. The high-temperature exposure of geopolymer samples (900 °C) caused a significant reduction in oxygen, and even more sodium, which led to the formation of a complex porous structure. As the concentration of NaOH (6 mol dm−3 and 8 mol dm−3) increased, new semi-crystalline phases of nepheline and sanidine were formed. Thermal properties were increasingly used to better understand and improve the properties of geopolymers at high temperatures. Temperature changes were monitored by simultaneous use of thermogravimetric analysis (TGA) and differential thermal analysis (DTA). The loss of mass of the investigated samples at 900 °C was in the range of 8–16%. Thermal treatment of geopolymers at 900 °C did not have much effect on the change in compressive strength of investigated samples. The results of thermal treatment of geopolymers at 900 °C showed that this is approximately the temperature at which the structure of the geopolymer turns into a ceramic-like structure. All investigated properties of the geopolymers are closely connected to the precursors and the constituents of the geopolymers.
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18
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Portland and Belite Cement Hydration Acceleration by C-S-H Seeds with Variable w/ c Ratios. MATERIALS 2022; 15:ma15103553. [PMID: 35629580 PMCID: PMC9147420 DOI: 10.3390/ma15103553] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 05/12/2022] [Accepted: 05/13/2022] [Indexed: 01/27/2023]
Abstract
The acceleration of very early age cement hydration by C-S-H seeding is getting attention from scholars and field applications because the enhanced early age features do not compromise later age performances. This acceleration could be beneficial for several low-CO2 cements as a general drawback is usually the low very early age mechanical strengths. However, the mechanistic understanding of this acceleration in commercial cements is not complete. Reported here is a contribution to this understanding from the study of the effects of C-S-H gel seeding in one Portland cement and two belite cements at two widely studied water-cement ratios, 0.50 and 0.40. Two commercially available C-S-H nano-seed-based admixtures, i.e., Master X-Seed 130 and Master X-Seed STE-53, were investigated. A multi-technique approach was adopted by employing calorimetry, thermal analysis, powder diffraction (data analysed by the Rietveld method), mercury intrusion porosimetry, and mechanical strength determination. For instance, the compressive strength at 1 day for the PC (w/c = 0.50) sample increased from 15 MPa for the unseeded mortar to 24 and 22 MPs for the mortars seeded with the XS130 and STE53, respectively. The evolution of the amorphous contents was determined by adding an internal standard before recording the powder patterns. In summary, alite and belite phase hydrations, from the crystalline phase content evolutions, are not significantly accelerated by C-S-H seedings at the studied ages of 1 and 28 d for these cements. Conversely, the hydration rates of tetracalcium alumino-ferrate and tricalcium aluminate were significantly enhanced. It is noted that the degrees of reaction of C4AF for the PC paste (w/c = 0.40) were 10, 30, and 40% at 1, 7, and 28 days. After C-S-H seeding, the values increased to 20, 45, and 60%, respectively. This resulted in larger ettringite contents at very early ages but not at 28 days. At 28 days of hydration, larger amounts of carbonate-containing AFm-type phases were determined. Finally, and importantly, the admixtures yielded larger amounts of amorphous components in the pastes at later hydration ages. This is justified, in part, by the higher content of amorphous iron siliceous hydrogarnet from the enhanced C4AF reactivity.
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Influence of Silica Fume on High-Calcium Fly Ash Expansion during Hydration. MATERIALS 2022; 15:ma15103544. [PMID: 35629570 PMCID: PMC9146364 DOI: 10.3390/ma15103544] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 05/09/2022] [Accepted: 05/11/2022] [Indexed: 11/17/2022]
Abstract
The purpose of this work was to study the possibility of neutralizing high-calcium fly ash expansion during hydration. The object of the study was the fly ash of Berezovskaya GRES, which is capable of independent setting and hardening. The test in the Le Chatelier molds showed that the divergence of indicator arms was 90–100 mm 1 day after mixing with water. The expansion and cracking of the fly ash could be completely prevented by silica fume addition in an amount of 42.9% by weight of the fly ash. At the same time, the compressive strength of specimens from the fly ash–sand paste in a ratio of 1:5 at the age of 28 days was 1.47 MPa. The isothermal heat release at a temperature of 20 °C for 10 days reached 500 kJ/kg. XRF and DTA results showed that free lime in the fly ash was completely hydrated in 11 days and gave the greatest expansion in the absence of silica fume. The presence of silica fume made the lime hydration incomplete and decreased the expansion. Unslaked free lime remained in the system. Exothermic data showed that silica fume inhibited CaO hydration from the reaction start.
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Removing Pollutants from Sewage Waters with Ground Apricot Kernel Shell Material. MATERIALS 2022; 15:ma15103428. [PMID: 35629454 PMCID: PMC9143833 DOI: 10.3390/ma15103428] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Revised: 05/03/2022] [Accepted: 05/04/2022] [Indexed: 02/01/2023]
Abstract
For the first time, a comprehensive review of the literature data on the use of apricot (Prunus armeniaca) biomass components as a sorption material for the treatment of wastewater and environmental water from various pollutants is carried out in the present study. In addition to a comprehensive analysis of contemporary studies, the current work carried out its own microstructural and energy dispersive studies. It shows that apricot kernel shell is a promising raw material for obtaining sorption materials that can be used to extract various pollutants from aqueous media. The parameters of sorption interaction are presented, at which the highest rate of removal of pollutants was achieved. It is shown that the sorption capacity of apricot biomass components can be increased by modifying it with various chemical reagents, as well as other physical and physicochemical methods. We reveal that most publications consider the use of the latter as a raw material for the production of activated carbons. It is established that the surface area and total pore space of activated carbons from apricot kernel shells depend on the modes of carbonization and activation. It is shown that activated carbons are effective adsorbents for removing various pollutants (metal ions, dyes, oil and oil products) from aqueous media. It was found that the adsorption isotherms of pollutants in most cases are best described by the Langmuir and Freundlich models, and the process kinetics is most often described by the pseudo-second-order model. The possibility of improving the sorption characteristics of apricot biomass during chemical or physicochemical treatment is also shown.
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21
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Mapping Research Knowledge on Rice Husk Ash Application in Concrete: A Scientometric Review. MATERIALS 2022; 15:ma15103431. [PMID: 35629457 PMCID: PMC9147154 DOI: 10.3390/ma15103431] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 05/01/2022] [Accepted: 05/04/2022] [Indexed: 02/02/2023]
Abstract
This study aimed to carry out a scientometric review of rice husk ash (RHA) concrete to assess the various aspects of the literature. Conventional review studies have limitations in terms of their capacity to connect disparate portions of the literature in a comprehensive and accurate manner. Science mapping, co-occurrence, and co-citation are a few of the most difficult phases of advanced research. The sources with the most articles, co-occurrences of keywords, the most prolific authors in terms of publications and citations, and areas actively involved in RHA concrete research are identified during the analysis. The Scopus database was used to extract bibliometric data for 917 publications that were then analyzed using the VOSviewer (version: 1.6.17) application. This study will benefit academics in establishing joint ventures and sharing innovative ideas and strategies because of the statistical and graphical representation of contributing authors and countries.
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22
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Lisowska A, Filipek-Mazur B, Komorowska M, Niemiec M, Bar-Michalczyk D, Kuboń M, Tabor S, Gródek-Szostak Z, Szeląg-Sikora A, Sikora J, Kocira S, Wasąg Z. Environmental and Production Aspects of Using Fertilizers Based on Waste Elemental Sulfur and Organic Materials. MATERIALS 2022; 15:ma15093387. [PMID: 35591722 PMCID: PMC9102313 DOI: 10.3390/ma15093387] [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: 04/08/2022] [Revised: 05/04/2022] [Accepted: 05/06/2022] [Indexed: 02/01/2023]
Abstract
Crop fertilization with sulfur is an important part of agricultural practices, as is the systematic increase in soil organic matter content. Materials of waste origin constitute a source of plant-available sulfur, as well as soil organic matter. The study was to verify the hypothesis assuming that combining waste sulfur pulp and its mixtures with organic materials enables simultaneous soil enrichment with readily available sulfur and organic matter. A 240-day incubation experiment was conducted, on two soils: very light and heavy; with two sulfur doses applied to each soil (20 and 40 mg S/kg d.m. for very light soil, and 30 and 60 mg S/kg d.m. for heavy soil). The sulfate sulfur content in the incubated soil material, treated with the addition of sulfur pulp and its mixtures with organic materials, increased significantly up to day 60 and then decreased. The application of these materials significantly increased the content of available sulfur and decreased the pH value of the incubated material. The effect of the introduced materials on dehydrogenase activity depended on soil granulometric composition (the impact of the applied materials on the activity of these enzymes in very light soil was small, and in heavy soil, their activity was usually limited by the presence of introduced materials). Application of the studied materials had little effect on the total organic carbon content in the incubated soil material (a significant change in the value of this parameter, in relation to the control soil, was recorded in some treatments of heavy soil).
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Affiliation(s)
- Aneta Lisowska
- Institute of Technology and Life Sciences, National Research Institute, Falenty, 3 Hrabska Av., 05-090 Raszyn, Poland; (A.L.); (D.B.-M.)
| | - Barbara Filipek-Mazur
- Department of Agricultural and Environmental Chemistry, University of Agriculture in Krakow, 21 Mickiewicza Av., 31-120 Krakow, Poland; (B.F.-M.); (M.K.)
| | - Monika Komorowska
- Department of Agricultural and Environmental Chemistry, University of Agriculture in Krakow, 21 Mickiewicza Av., 31-120 Krakow, Poland; (B.F.-M.); (M.K.)
| | - Marcin Niemiec
- Department of Agricultural and Environmental Chemistry, University of Agriculture in Krakow, 21 Mickiewicza Av., 31-120 Krakow, Poland; (B.F.-M.); (M.K.)
- Correspondence:
| | - Dominika Bar-Michalczyk
- Institute of Technology and Life Sciences, National Research Institute, Falenty, 3 Hrabska Av., 05-090 Raszyn, Poland; (A.L.); (D.B.-M.)
| | - Maciej Kuboń
- Faculty of Production and Power Engineering, University of Agriculture in Krakow, 30-149 Krakow, Poland; (M.K.); (A.S.-S.); (J.S.)
| | - Sylwester Tabor
- Department of Production Engineering, Logistics and Applied Computer Science, Faculty of Production and Power Engineering, University of Agriculture in Krakow, Mickiewicza 21, 30-120 Krakow, Poland;
| | - Zofia Gródek-Szostak
- Department of Economics and Enterprise Organization, Cracow University of Economics, 31-510 Krakow, Poland;
| | - Anna Szeląg-Sikora
- Faculty of Production and Power Engineering, University of Agriculture in Krakow, 30-149 Krakow, Poland; (M.K.); (A.S.-S.); (J.S.)
- Institute of Management and Production Engineering, Cavalry Captain Witold Pilecki State University of Małopolska in Oświęcim, Maksymiliana Kolbego 8, 32-600 Oswiecim, Poland
| | - Jakub Sikora
- Faculty of Production and Power Engineering, University of Agriculture in Krakow, 30-149 Krakow, Poland; (M.K.); (A.S.-S.); (J.S.)
- Institute of Management and Production Engineering, Cavalry Captain Witold Pilecki State University of Małopolska in Oświęcim, Maksymiliana Kolbego 8, 32-600 Oswiecim, Poland
| | - Sławomir Kocira
- Department of Machinery Exploitation and Management of Production Processes, University of Life Sciences in Lublin, Akademicka 13, 20-950 Lublin, Poland;
| | - Zbigniew Wasąg
- Jan Zamoyski College of Humanities and Economics in Zamość, ul. Koszary 8, 22-400 Zamość, Poland;
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Radiological Characteristics of Carbonated Portland Cement Mortars Made with GGBFS. MATERIALS 2022; 15:ma15093395. [PMID: 35591734 PMCID: PMC9100595 DOI: 10.3390/ma15093395] [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: 04/01/2022] [Revised: 05/05/2022] [Accepted: 05/07/2022] [Indexed: 11/20/2022]
Abstract
The objective of this study is to assess whether the carbonation process can modify the physicochemical characteristics of the natural radionuclides of the three natural radioactive series, together with 40K. Three mortar specimens with different percentages of ground granulated blast-furnace slag (GGBFS), cured under water for 1, 3, 7, 14, or 28 days, were subjected to a natural carbonation process. Activity concentrations for the solid and ground mortars were determined by gamma spectrometry and by radiochemical separation of isotopic uranium. The novelty of this paper relies principally on the study we have carried out, for the first time, of the radiological characteristics of carbonated Portland cement mortars. It was found that the chemical properties of the 3 mortar specimens were not affected by the carbonation process, with particular attention placed on uranium (238U, 235U, and 234U), the activity concentrations of which were equivalent to the 226Ra results and ranged from 5.5 ± 1.6 Bq kg−1 to 21.4 ± 1.2 Bq kg−1 for the 238U. The average activity concentrations for the 3 types of mortars were lower than 20.1 Bq kg−1, 14.5 Bq kg−1, and 120.2 Bq kg−1 for the 226Ra, 232Th (212Pb), and 40K, respectively. Annual effective dose rates were equivalent to the natural background of 0.024 mSv. In addition, it was observed that the variation rate for the 222Rn emanation was due primarily to the Portland cement hydration and not due to the pore size redistribution as a consequence of the carbonation process. This research will provide new insights into the potential radiological risk from carbonated cement-based materials. Moreover, the assessment that is presented in this study will convey valuable information for future research that will explore the activity concentration of building materials containing NORM materials.
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Harirchi P, Yang M. Exploration of Carbon Dioxide Curing of Low Reactive Alkali-Activated Fly Ash. MATERIALS 2022; 15:ma15093357. [PMID: 35591691 PMCID: PMC9099501 DOI: 10.3390/ma15093357] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Revised: 04/30/2022] [Accepted: 05/04/2022] [Indexed: 02/04/2023]
Abstract
In this paper, the effect of carbon curing procedure on low reactive fly ash alkali-activated pastes was investigated. Specimens were cured with pure carbon dioxide (CO2) gas for different curing times under 4 bar pressure. Chemical and physical characteristics of the geopolymer pastes were obtained from mass monitoring, titration test, XRD, FTIR and TGA-DTG analyses. Regarding the test results, after three days of CO2 curing, the highest CO2uptake was obtained at 4.8 wt% of fly ash precursor, with carbon sequestration efficiency at 22.6%. The ratio of carbon dioxide absorbed as efflorescence to the total absorbed CO2 was measured. The results show that at early age, almost 50% of carbonated products appeared as efflorescence; however, by increasing the curing time, and after 3 days of curing, about 80% of carbon dioxide was stored in the matrix. It was found that, in all cases, carbonation curing was detrimental to the geopolymerization process due to a high amount of efflorescence and led to a reduction in the compressive strength. At 24 h and 3 days, the specimens showed a lower reduction in compressive strength in comparison to CO2 samples cured at 3 h, 6 h and 12 h. Regarding the XRD results, calcite was detected in the 24 h and 3 days specimens, which contributes to lower pore sizes due to a higher molar volume and production of silica gel that might participate in the polymerization processes and results in densified microstructures.
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Artificial Neural Network-Forecasted Compression Strength of Alkaline-Activated Slag Concretes. SUSTAINABILITY 2022. [DOI: 10.3390/su14095214] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
The utilization of ordinary Portland cement (OPC) in conventional concretes is synonymous with high carbon emissions. To remedy this, an environmentally friendly concrete, alkaline-activated slag concrete (AASC), where OPC is completely replaced by ground granulated blast-furnace slag (GGBFS) industrial waste, is one of the currently pursued research interests. AASC is not commonly used in the construction industry due to limitations in experience and knowledge on the mix proportions and mechanical properties. To circumvent great labour in the experimental works toward the determination of the optimal properties, this study, therefore, presents the compressive strength prediction of AASC by employing the back-propagation artificial neural network (ANN) modelling technique. To construct this model, a sufficiently equipped experimental databank was built from the literature covering varied mix proportion effects on the compressive strength of AASC. For this, four model variants with different input parameter considerations were examined and the ideal ANN architecture for each model with the best input number–hidden layer neuron number–output number format was identified to improve its prediction accuracy. From such a setting, the most accurate prediction model with the highest determination coefficient, R2, of 0.9817 was determined, with an ANN architecture of 8-18-1 containing inputs such as GGBFS, a fine to total aggregate ratio, sodium silicate, sodium hydroxide, mixing water, silica modulus of activator, percentage of sodium oxide and water–binder ratio. The prediction accuracy of the optimal ANN model was then compared to existing ANN-based models, while the variable selection was compared to existing AASC models with other machine learning algorithms, due to limitations in the ANN-based model. To identify the parametric influence, the individual relative importance of each input variable was determined through a sensitivity analysis using the connection weight approach, whose results indicated that the silica modulus of the activator and sodium silicate greatly affected the AASC compressive strength. The proposed methodology demonstrates that the ANN-based model can predict the AASC compressive strength with a high accuracy and, consequently, aids in promoting the utilization of AASC in the construction industry as green concrete without performing destructive tests. This prediction model can also accelerate the use of AASC without using a cement binder in the concrete matrix, leading to produce a sustainable construction material.
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Cyclically Loaded Copper Slag Admixed Reinforced Concrete Beams with Cement Partially Replaced with Fly Ash. MATERIALS 2022; 15:ma15093101. [PMID: 35591435 PMCID: PMC9105895 DOI: 10.3390/ma15093101] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 02/12/2022] [Accepted: 02/25/2022] [Indexed: 12/10/2022]
Abstract
Generally, the concrete with higher strength appears to produce brittle failure more easily. However, the use of mineral admixture can help in enhancing the ductility, energy dissipation, and seismic energy in the designed concrete. This paper presents energy absorption capacity, stiffness degradation, and ductility of the copper slag (CS) admixed reinforced concrete with fly ash (FA) beams subjected to forward cyclic load. The forward cyclic load was applied with the help of servo-hydraulic universal testing machines with 250 kN capacity. Twenty-four beams with a size of 100 mm × 150 mm × 1700 mm made with CS replaced for natural sand from 0% to 100% at an increment of 20%, and FA was replaced for cement from 0% to 30% with an increment of 10% were cast. Beams are designed for the grade of M30 concrete. Based on the preliminary investigation results, compressive strength of the concrete greatly increased when adding these two materials in the concrete. Normally, Grade of concrete can change the behaviour of the beam from a brittle manner to be more ductile manner. So, in this work, flexural behaviour of RC beams are studied with varying compressive strength of concrete. Experimental results showed that the RC beam made with 20% FA and 80% CS (FA20CS80) possesses higher ultimate load-carrying capacity than the control concrete beam. It withstands up to 18 cycles of loading with an ultimate deflection of 60 mm. The CS and FA admixed reinforced concrete composite beams have excellent ultimate load carrying capacity, stiffness, energy absorption capacity, and ductility indices compared to the control concrete beam.
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Fly Ash Application as Supplementary Cementitious Material: A Review. MATERIALS 2022; 15:ma15072664. [PMID: 35407996 PMCID: PMC9000507 DOI: 10.3390/ma15072664] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 03/24/2022] [Accepted: 03/25/2022] [Indexed: 11/24/2022]
Abstract
This study aimed to expand the knowledge on the application of the most common industrial byproduct, i.e., fly ash, as a supplementary cementitious material. The characteristics of cement-based composites containing fly ash as supplementary cementitious material were discussed. This research evaluated the mechanical, durability, and microstructural properties of FA-based concrete. Additionally, the various factors affecting the aforementioned properties are discussed, as well as the limitations associated with the use of FA in concrete. The addition of fly ash as supplementary cementitious material has a favorable impact on the material characteristics along with the environmental benefits; however, there is an optimum level of its inclusion (up to 20%) beyond which FA has a deleterious influence on the composite’s performance. The evaluation of the literature identified potential solutions to the constraints and directed future research toward the application of FA in higher amounts. The delayed early strength development is one of the key downsides of FA use in cementitious composites. This can be overcome by chemical activation (alkali/sulphate) and the addition of nanomaterials, allowing for high-volume use of FA. By utilizing FA as an SCM, sustainable development may promote by lowering CO2 emissions, conserving natural resources, managing waste effectively, reducing environmental pollution, and low hydration heat.
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Improving the Durability of Lime Finishing Mortars by Modifying Them with Silicic Acid Sol. MATERIALS 2022; 15:ma15072360. [PMID: 35407694 PMCID: PMC8999692 DOI: 10.3390/ma15072360] [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: 01/29/2022] [Revised: 02/21/2022] [Accepted: 02/24/2022] [Indexed: 11/16/2022]
Abstract
Lime materials are in great demand for the restoration of the walls of historical buildings. However, lime coatings have insufficient resistance during operation. The purpose of this work was the modification of lime mortars with silicic acid sol in order to obtain more durable crystalline materials for construction purposes. A technology has been developed for obtaining a silica-containing additive, which consists in passing a liquid glass solution with a density of 1.053 kg/m3 through a cationic column and obtaining a silicic acid sol with a pH of 3–4 and a charge of (−) 0.053 V. The regeneration time and the amount of sol have been determined. Regularities of change in the radius of particles of silicic acid sol depending on age are determined. It is established that at an early age (up to 5 days), the radius of sol particles can be determined in accordance with the Rayleigh equation, and at a later age, in accordance with the Heller equation. The results of the calculation show that at the age of 1–5 days, the radius of the sol particles is 17.1–17.9 nm, and then the particles become coarser and the particle radius is 131.2–143 nm at the age of 19 days. The work of adhesion of silicic acid sol to lime and the heat of wetting are estimated. It is shown that the work of adhesion of water to lime is 28.9 erg/cm2, and that of the sol is 32.8 erg/cm2. The amount of heat Q released when lime is wetted with SiO2 sol is 15.0 kJ/kg, and when lime is wetted with water, it is 10.6 kJ/kg.
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Numerical Analysis of Piled-Raft Foundations on Multi-Layer Soil Considering Settlement and Swelling. BUILDINGS 2022. [DOI: 10.3390/buildings12030356] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Numerical modelling can simulate the interaction between structural elements and the soil continuum in a piled-raft foundation. The present work utilized a two-dimensional finite element Plaxis 2D software to investigate the settlement, swelling, and structural behavior of foundations during the settlement and swelling of soil on various soil profiles under various load combinations and geometry conditions. The field and laboratory testing have been performed to determine the behavior soil parameters necessary for numerical modelling. The Mohr–Coulomb model is utilized to simulate the behavior of soil, as this model requires very few input parameters, which is important for the practical geotechnical behavior of soil. From this study, it was observed that, as soil is soft and has less stiffness, the un-piled raft was not sufficient to resists and higher loads and exceeds the limits of settlement. Piled raft increases the load carrying capacity of soil, and the lower soil layer has a higher stiffness where the pile rests, decreasing the significant settlement. Further, the effects of (L/d) and (s/d) of the pile and Krs on the settlement are also discussed, detailed numerically under different scenarios. The swelling of expansive soil was also simulated in Plaxis 2D with an application of positive volumetric strain. The above-mentioned parametric study was similarly implemented for the heaving of foundation on expansive soil.
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Compaction Characteristics and Permeability of Expansive Shale Stabilized with Locally Produced Waste Materials. MATERIALS 2022; 15:ma15062138. [PMID: 35329586 PMCID: PMC8951604 DOI: 10.3390/ma15062138] [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: 01/30/2022] [Revised: 03/01/2022] [Accepted: 03/09/2022] [Indexed: 11/16/2022]
Abstract
Waste is available in an abundant form and goes to landfill without any use, creating threats to the environment. Recent and past studies have used different types of waste to stabilize soil and reduce environmental impacts. However, there is a lack of studies on the combined use of marble dust, rice-husk ash, and saw dust in expansive shale soil. The current study tries to overcome such a gap in the literature, studying the effect of marble dust, rice-husk ash, and saw dust on expansive shale’s compaction characteristics and permeability properties. According to unified soil classification and the AAHTO classification system, the geotechnical properties of natural soil are classified as clay of high plasticity (CH) and A-7-5. Several tests are performed in the laboratory to investigate the compaction characteristics and permeability properties of expansive shale. Moreover, permeability apparatus is used to investigate the permeability properties of soil. In addition, due to the accuracy of the apparatus, the conventional apparatus has been partly modified. The experimental results show that the addition of waste to the soil has significantly improved soil stabilization, increasing permeability and decreasing plasticity indexes. In addition, there is a gradual decrease in the dry density of soil and an increase in the permeability of stabilized soil. Based on the outcomes of the current study, it claims and concludes that these waste materials can be used as soil stabilizers or modifiers, instead of being dumped in landfill, which will provide a green, friendly, and sustainable environment. The current study recommends that future researchers use various wastes in the concrete and soil to improve their compaction and mechanical properties.
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Wang Q, Ahmad W, Ahmad A, Aslam F, Mohamed A, Vatin NI. Application of Soft Computing Techniques to Predict the Strength of Geopolymer Composites. Polymers (Basel) 2022; 14:polym14061074. [PMID: 35335405 PMCID: PMC8956037 DOI: 10.3390/polym14061074] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 02/24/2022] [Accepted: 02/26/2022] [Indexed: 11/17/2022] Open
Abstract
Geopolymers may be the best alternative to ordinary Portland cement because they are manufactured using waste materials enriched in aluminosilicate. Research on geopolymer composites is accelerating. However, considerable work, expense, and time are needed to cast, cure, and test specimens. The application of computational methods to the stated objective is critical for speedy and cost-effective research. In this study, supervised machine learning approaches were employed to predict the compressive strength of geopolymer composites. One individual machine learning approach, decision tree, and two ensembled machine learning approaches, AdaBoost and random forest, were used. The coefficient correlation (R2), statistical tests, and k-fold analysis were used to determine the validity and comparison of all models. It was discovered that ensembled machine learning techniques outperformed individual machine learning techniques in forecasting the compressive strength of geopolymer composites. However, the outcomes of the individual machine learning model were also within the acceptable limit. R2 values of 0.90, 0.90, and 0.83 were obtained for AdaBoost, random forest, and decision models, respectively. The models’ decreased error values, such as mean absolute error, mean absolute percentage error, and root-mean-square errors, further confirmed the ensembled machine learning techniques’ increased precision. Machine learning approaches will aid the building industry by providing quick and cost-effective methods for evaluating material properties.
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Affiliation(s)
- Qichen Wang
- Department of Civil and Environmental Engineering, University of Iowa, Iowa City, IA 52242, USA
- Correspondence: (Q.W.); (W.A.)
| | - Waqas Ahmad
- Department of Civil Engineering, COMSATS University Islamabad, Abbottabad 22060, Pakistan;
- Correspondence: (Q.W.); (W.A.)
| | - Ayaz Ahmad
- Department of Civil Engineering, COMSATS University Islamabad, Abbottabad 22060, Pakistan;
- Faculty of Civil Engineering, Cracow University of Technology, 24 Warszawska Str., 31-155 Cracow, Poland
| | - Fahid Aslam
- Department of Civil Engineering, College of Engineering in Al-Kharj, Prince Sattam bin Abdulaziz University, Al-Kharj 11942, Saudi Arabia;
| | - Abdullah Mohamed
- Research Centre, Future University in Egypt, New Cairo 11745, Egypt;
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The Effect of POFA-Gypsum Binary Mixture Replacement on the Performance of Mechanical and Microstructural Properties Enhancements of Clays. MATERIALS 2022; 15:ma15041532. [PMID: 35208072 PMCID: PMC8874557 DOI: 10.3390/ma15041532] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 02/07/2022] [Accepted: 02/15/2022] [Indexed: 02/04/2023]
Abstract
Soft clay is categorized as problematic due to its weak and dispersive properties which requires stabilization. In Malaysia, there is another challenge, the increment of palm oil waste productions to meet the global demand for food oil. These two concerns motivate engineers to develop novel strategies for exploiting palm oil waste in soil stabilization. Utilizing POFA as a soil stabilizing agent is an economical and sustainable option due to that POFA contains high pozzolanic characteristics which make it more suitable and reliable to treat soft soil. This study uses the replacement portion of the soil with stabilizing agents -POFA and Gypsum; aiming to achieve Malaysia green technology goals by the balance of the economic expansion and environmental privilege. However, the aim of this study is to determine the effect of POFA-gypsum binary mixture replacement on the performance of mechanical and microstructural properties en-hancements of clays. Kaolin S300 is the control sample whereas POFA and gypsum are the used binders. The mechanical properties and shear strength with the curing period were tested. Results showed that treated clay marked increment of optimum water contents and reduction of maximum dry densities, a clear 200% of enhancement of treated clay’s compressive and shear strength with curing period as well as the amount of stabilizing agent to less than 15% of POFA and 6% of POFA. It is also found that as gypsum contains a high amount of lime (CaO), the results illustrate that strength raises significantly even with less curing time due to its high reactivity compared to silica and alu-mina. Overall, the results show an enhancement of mechanical and shear strength properties of treated kaolin supported by microstructural SEM imaging.
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Subash N, Avudaiappan S, Adish Kumar S, Amran M, Vatin N, Fediuk R, Aepuru R. Experimental Investigation on Geopolymer Concrete with Various Sustainable Mineral Ashes. MATERIALS 2021; 14:ma14247596. [PMID: 34947190 PMCID: PMC8704019 DOI: 10.3390/ma14247596] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 11/21/2021] [Accepted: 11/23/2021] [Indexed: 12/01/2022]
Abstract
The aim of this research was to find the best alternative for river sand in concrete. In both geopolymer concrete (GPC) and cement concrete (CC), the fine aggregates are replaced with various sustainable mineral ashes, and mechanical and durability tests are conducted. Specimens for tests were made of M40 grade GPC and CC, with five different soil types as river sand substitute. The materials chosen to replace the river sand are manufactured sand (M-sand), sea sand, copper slag, quarry dust, and limestone sand as 25%, 50%, 75%, and 100%, respectively by weight. GPF50 and CC50 were kept as control mixes for GPC and CC, respectively. The test results of respective concretes are compared with the control mix results. From compressive strength results, M-sand as a fine aggregate had an increase in strength in every replacement level of GPC and CC. Additionally, copper slag is identified with a significant strength reduction in GPC and CC after 25% replacement. Copper slag, quarry dust, and limestone sand in GPC and CC resulted in considerable loss of strength in all replacement levels except for 25% replacement. The cost of GPC and CC is mixed with the selected fine aggregate replacement materials which arrived. Durability and cost analyses are performed for the advisable mixes and control mixes to have a comparison. Durability tests, namely, water absorption and acid tests and water permeability and thermal tests are conducted and discussed. Durability results also indicate a positive signal to mixes with M-sand. The advisable replacement of river sand with each alternative is discussed.
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Affiliation(s)
- Narayanan Subash
- Department of Civil Engineering, University College of Engineering Nagercoil, Nagercoil 629004, India;
| | - Siva Avudaiappan
- Departamento de Ingeniería en Obras Civiles, Universidad de Santiago de Chile, Av. Ecuador 3659, Estación Central 7800002, Chile
- Correspondence: (S.A.); (M.A.)
| | - Somanathan Adish Kumar
- Department of Civil Engineering, University VOC College of Engineering, Thoothukudi 628008, India;
| | - Mugahed Amran
- Department of Civil Engineering, College of Engineering, Prince Sattam Bin Abdulaziz University, Alkharj 16273, Saudi Arabia
- Department of Civil Engineering, Faculty of Engineering and IT, Amran University, Amran 9677, Yemen
- Correspondence: (S.A.); (M.A.)
| | - Nikolai Vatin
- Peter the Great St. Petersburg Polytechnic University, 195251 St. Petersburg, Russia;
| | - Roman Fediuk
- Polytechnic Institute, Far Eastern Federal University, 690922 Vladivostok, Russia;
| | - Radhamanohar Aepuru
- Departamento de Ingeniería Mecánica, Facultad de Ingeniería, Universidad Tecnologica Metropolitana, Santiago 1242, Chile;
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Kočí V, Kočí J, Fořt J, Fiala L, Šál J, Hager I, Černý R. Utilization of Crushed Pavement Blocks in Concrete: Assessment of Functional Properties and Environmental Impacts. MATERIALS 2021; 14:ma14237361. [PMID: 34885513 PMCID: PMC8658445 DOI: 10.3390/ma14237361] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 11/03/2021] [Accepted: 11/29/2021] [Indexed: 01/18/2023]
Abstract
Production of concrete is connected to extensive energy demands, greenhouse gases production or primary sources depletion. Reflecting current economical, social, or environmental trends, there is strong pressure on mitigation these requirements and impacts. The exploitation of secondary- or waste materials in production processes has therefore a great potential which is not related solely to binders but also to fillers. In this light, this paper aims at thorough investigations of concrete mixtures with crushed concrete pavements as partial or full replacement of natural coarse aggregates. The research combines experimental techniques to quantify the influence of the substitution on basic physical, mechanical, and heat/moisture transport/storage parameters. The experimental data obtained are further exploited as input data for computational prediction of coupled heat and moisture transport to assess the influence of the aggregates substitution on hygrothermal performance of the built-in concretes. In the last step, the environmental impacts are assessed. Since the changes in the hygrothermal performance were found to be insignificant (i), the compressive strength were improved by up to 25% (ii) and most of the environmental impact indicators were decreased (iii) at the same time, the findings of the research presented predeterminate such a reuse strategy to wider application and use.
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Affiliation(s)
- Václav Kočí
- Department of Materials Engineering and Chemistry, Faculty of Civil Engineering, Czech Technical University in Prague, Thákurova 7/2077, 166 29 Prague 6, Czech Republic; (J.K.); (J.F.); (L.F.); (R.Č.)
- Correspondence: ; Tel.: +420-2-2435-7125
| | - Jan Kočí
- Department of Materials Engineering and Chemistry, Faculty of Civil Engineering, Czech Technical University in Prague, Thákurova 7/2077, 166 29 Prague 6, Czech Republic; (J.K.); (J.F.); (L.F.); (R.Č.)
| | - Jan Fořt
- Department of Materials Engineering and Chemistry, Faculty of Civil Engineering, Czech Technical University in Prague, Thákurova 7/2077, 166 29 Prague 6, Czech Republic; (J.K.); (J.F.); (L.F.); (R.Č.)
| | - Lukáš Fiala
- Department of Materials Engineering and Chemistry, Faculty of Civil Engineering, Czech Technical University in Prague, Thákurova 7/2077, 166 29 Prague 6, Czech Republic; (J.K.); (J.F.); (L.F.); (R.Č.)
| | - Jiří Šál
- Institute of Technology and Business in České Budějovice, Okružní 517/10, 370 01 České Budějovice, Czech Republic;
| | - Izabela Hager
- Faculty of Civil Engineering, Cracow University of Technology, 24 Warszawska St., 31-155 Cracow, Poland;
| | - Robert Černý
- Department of Materials Engineering and Chemistry, Faculty of Civil Engineering, Czech Technical University in Prague, Thákurova 7/2077, 166 29 Prague 6, Czech Republic; (J.K.); (J.F.); (L.F.); (R.Č.)
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Prediction of Pore Volume Dispersion and Microstructural Characteristics of Concrete Using Image Processing Technique. CRYSTALS 2021. [DOI: 10.3390/cryst11121476] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Concrete has served an essential role in many infrastructural projects. Factors including pore percentage, pore distribution, and cracking affect concrete durability. This research aims to better understand pore size distribution in cement-based materials. Micro-computed tomography (micro-CT) pictures were utilised to characterise the interior structure of specimens without destroying them. The pore dispersion of the specimens was displayed in 3D, utilising the data and imaging techniques collected, and the pore volume dispersion was examined using a volume-based approach. Another way to describe heterogeneous pore features is the chord-length distribution, which was calculated from three-dimensional micro-CT scans and correlated with the traditional method. The collected specimens were subjected to physical and mechanical testing. In addition, image processing techniques were used to conduct the studies. The results showed that the chord-length distribution-based pore size distribution is very successful than the traditional volume-based technique. The acquired data could be used for research and to forecast the characteristics of the materials.
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Influence of Mechanochemical Activation of Concrete Components on the Properties of Vibro-Centrifugated Heavy Concrete. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app112210647] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
One of the crucial problems in current construction is energy, resource, and material efficient technologies in both industrial and civil engineering, associated with new material manufacturing and building construction. This article is devoted to developing comprehensive technology for activation effects on concrete made by various production techniques: vibration, centrifugation, and vibro-centrifugation. The possibility of a significant improvement in the microstructure of concrete and obtaining materials with increased specified characteristics, depending on its manufacturing technology, were studied during the complex activation effect exposed to this concrete and its components. Chemical activation of water and mechanical activation of cement were considered. The urgency and prospects of double, complex mechanochemical activation of concrete mixture components were substantiated. It was proven that the complex mechanochemical activation of the concrete mixture components gives a synergistic effect in obtaining concrete composition with an improved structure and improved characteristics. Furthermore, the relationship between concrete production technology and the technology of activation of its components was established. It was revealed that the most effective is the complex mechanochemical activation of vibro-centrifuged concrete, which gives an increase in strength up to 30%. The study results indicate a further direction of development associated with an increase in variatropic characteristics using both prescription and technological factors.
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Petropavlovskii K, Novichenkova T, Petropavlovskaya V, Sulman M, Fediuk R, Amran M. Faience Waste for the Production of Wall Products. MATERIALS 2021; 14:ma14216677. [PMID: 34772201 PMCID: PMC8587780 DOI: 10.3390/ma14216677] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 10/31/2021] [Accepted: 11/02/2021] [Indexed: 11/16/2022]
Abstract
Increasing the efficiency of using gypsum binders can be carried out by using not natural gypsum raw materials, but calcium sulfate-containing waste from various industries (phosphogypsum, borogypsum, citrogypsum, etc.). As the main source material in the work, we used gypsum-containing waste from a faience factory in the form of waste molds for casting dishes, souvenirs and plumbing fixtures. It has been established that the optimal binding system is formed by mixing powders of dihydrate technogenic gypsum from a coarse and fine earthenware factory with average particle diameters of 3.473 microns and 3.065 microns in a percentage ratio of 30:70, respectively. Using a computer software developed by the authors, which makes it possible to simulate the microstructure of a raw mixture taking into account the contact interaction of particles and calculate the average coordination number, models of binary packing of particles were constructed at various ratios of their diameters. Studies of the strength of composites obtained on the basis of bidisperse systems have shown the presence of an extremum in the region of mixtures containing 30% coarse powder. With optimal packing, a large number of phase contacts are formed due to the regulation of the grain composition of the bidisperse system. It was revealed that a brick based on the waste of two-water gypsum from earthenware production has 2.5–5 times better characteristics of compressive strength than traditional building wall products based on natural gypsum. At the same time, the strength immediately after molding is more than 3 times higher than that of traditional gypsum products. Even higher indicators are achieved when adding microcalcite in addition to the waste of earthenware production, in this case, the compressive strength is 3–6 times higher, and the strength immediately after molding is almost 3 times higher than that of traditional gypsum products.
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Affiliation(s)
| | | | | | - Mikhail Sulman
- Tver State Technical University, 170026 Tver, Russia; (T.N.); (V.P.); (M.S.)
| | - Roman Fediuk
- Polytechnic Institute, Far Eastern Federal University, 690922 Vladivostok, Russia
- Correspondence: authors:
| | - Mugahed Amran
- Department of Civil Engineering, College of Engineering, Prince Sattam Bin Abdulaziz University, Alkharj 11942, Saudi Arabia;
- Department of Civil Engineering, Faculty of Engineering and IT, Amran University, Amran 9677, Yemen
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Grădinaru CM, Șerbănoiu AA, Muntean R, Șerbănoiu BV. The Synergy between Bio-Aggregates and Industrial Waste in a Sustainable Cement Based Composite. MATERIALS 2021; 14:ma14206158. [PMID: 34683750 PMCID: PMC8540469 DOI: 10.3390/ma14206158] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 10/13/2021] [Accepted: 10/15/2021] [Indexed: 11/16/2022]
Abstract
The effects of the fly ash and of the sunflower stalks and corn cobs within a cement-matrix composite were studied under the aspects of density, compressive strength, splitting tensile strength, elasticity modulus, and resistance to repeated freeze-thaw cycles. In the research were developed 20 recipes of cement-based composite, including the reference composite. Fly ash was used as partial cement replacement (10, 20 and 30% by volume), and the vegetal aggregates made by corn cobs and sunflower stalks as partial replacement of the mineral aggregates (25 and 50% by volume). The study results revealed that a lightweight composite can be obtained with 50% of vegetal aggregates, and the fly ash, no matter its percentage, enhanced the compressive strength and splitting tensile strength of the compositions with 50% of sunflower aggregates and the freeze-thaw resistance of all compositions with sunflower stalks.
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Affiliation(s)
- Cătălina Mihaela Grădinaru
- Faculty of Civil Engineering and Building Services, “Gheorghe Asachi” Technical University of Iași, 700050 Iași, Romania;
| | - Adrian Alexandru Șerbănoiu
- Faculty of Civil Engineering and Building Services, “Gheorghe Asachi” Technical University of Iași, 700050 Iași, Romania;
- Correspondence:
| | - Radu Muntean
- Faculty of Civil Engineering, Transilvania University of Brașov, 500152 Brașov, Romania;
| | - Bogdan Vasile Șerbănoiu
- Faculty of Architecture “G.M. Cantacuzino”, “Gheorghe Asachi” Technical University of Iași, 700050 Iași, Romania;
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Experimental Investigation and Image Processing to Predict the Properties of Concrete with the Addition of Nano Silica and Rice Husk Ash. CRYSTALS 2021. [DOI: 10.3390/cryst11101230] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The use of the combination of ultrafine rice husk ash (RHA) and nano silica (NS) enhances the compactness of hardened concrete, but there is still a lack of studies that address the effects of NS and RHA on the workability, mechanical properties and pore microstructure of concrete. This study mainly aims to investigate the influence of the pore size distribution in multiphysics concrete model modified by NS and RHA and to determine the workability and mechanical properties of concrete with NS and RHA. In this work, NS and RHA were used as 0, 5, 10, 15 and 20% replacements of ordinary Portland cement (OPC) in concrete grade M20. Concrete mixed with NS and RHA showed improved performance for up to 10% addition of NS and RHA. Further addition of NS and RHA showed a decrease in performance at 7, 14 and 28 days. The decrease in concrete porosity was also found to be up to 10% when adding NS and RHA to cement. Image processing was performed on the cement-based materials to describe the microstructure of the targeted material without damage. The results from the experimental and tomography images were utilized to investigate the concrete microstructure and predict its inner properties.
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Influence of Composition and Technological Factors on Variatropic Efficiency and Constructive Quality Coefficients of Lightweight Vibro-Centrifuged Concrete with Alkalized Mixing Water. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11199293] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Alkalization technology and its application to obtain high-performance concrete compositions is an urgent scientific problem that opens opportunities for improving building structures. The article is devoted to the new technology of manufacturing reinforced concrete structures with low energy consumption, resource, and labor intensity based on the improved variatropic configuration of vibro-centrifuged concrete using activated water with high pH. The synergistic effect of the joint use of the proposed novel solutions has been theoretically and experimentally proved. Thus, growth in physical and mechanical characteristics of up to 15–20% was obtained, the structure and its operational ability were improved (the effectiveness of structural improvement, expressed as a percentage, reached values over 70%, concerning control samples). A positive effect on the properties of vibro-centrifuged concrete over the entire thickness of the annular section has been revealed. A method for controlling the integral characteristics of concrete has been obtained. The possibility of regulating the variatropic structure and controlling the differential characteristics of vibro-centrifuged concrete has been established. An assessment of the constructive quality and variatropic efficiency of vibro-centrifuged concrete was carried out, and new calculated dependencies were proposed, expressed in the form of relative coefficients.
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Application of Advanced Machine Learning Approaches to Predict the Compressive Strength of Concrete Containing Supplementary Cementitious Materials. MATERIALS 2021; 14:ma14195762. [PMID: 34640160 PMCID: PMC8510219 DOI: 10.3390/ma14195762] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 09/22/2021] [Accepted: 09/29/2021] [Indexed: 11/16/2022]
Abstract
The casting and testing specimens for determining the mechanical properties of concrete is a time-consuming activity. This study employed supervised machine learning techniques, bagging, AdaBoost, gene expression programming, and decision tree to estimate the compressive strength of concrete containing supplementary cementitious materials (fly ash and blast furnace slag). The performance of the models was compared and assessed using the coefficient of determination (R2), mean absolute error, mean square error, and root mean square error. The performance of the model was further validated using the k-fold cross-validation approach. Compared to the other employed approaches, the bagging model was more effective in predicting results, with an R2 value of 0.92. A sensitivity analysis was also prepared to determine the level of contribution of each parameter utilized to run the models. The use of machine learning (ML) techniques to predict the mechanical properties of concrete will be beneficial to the field of civil engineering because it will save time, effort, and resources. The proposed techniques are efficient to forecast the strength properties of concrete containing supplementary cementitious materials (SCM) and pave the way towards the intelligent design of concrete elements and structures.
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The Apparent Activation Energy of a Novel Low-Calcium Silicate Hydraulic Binder. MATERIALS 2021; 14:ma14185347. [PMID: 34576569 PMCID: PMC8469558 DOI: 10.3390/ma14185347] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 08/19/2021] [Accepted: 09/13/2021] [Indexed: 11/16/2022]
Abstract
In this work, the apparent activation energy (Ea) of a novel low-calcium binder was, for the first time, experimentally determined, using a calorimetric approach. Additionally, a correlation between the Ea, measured at the acceleration period with the C/S ratio of the hydration product is proposed. The Ea of the prepared pastes was determined through isothermal calorimetry tests by calculating the specific rate of reaction at different temperatures, using two different approaches. When comparing the Ea, at the acceleration period of this novel binder with the one published for alite and belite, we observed that its value is higher, which may be a result of a different hydration product formed with a distinct C/S ratio. Finally, to study the temperature effect on the compressive strength at early ages, a set of experiments with mortars was performed. The results showed that the longer the curing time at 35 °C, the higher the compressive strength after 2 days of hydration, which suggests a higher initial development of hydration products. This study also indicated that the novel binder has a higher sensitivity to temperature when compared with ordinary Portland cement (OPC).
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