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Showing papers on "Cement published in 2022"


Journal ArticleDOI
TL;DR: In this article , the influence of recycled aggregate addition on the fresh and hardened properties of geopolymer concrete is comprehensively reviewed in this paper, and the studies suggest significant improvement in the workability on addition of recycled aggregates to geopolymer concrete.
Abstract: Several industrial by-products are extensively used again as a supplementary cementitious material or aggregates in the interest to reduce environmental footprints in terms of energy depletion, pollution, waste disposition, resource depletion, and global warming related with conventional cement. A remarkable quantity of industrial scrap materials, primarily designated as construction and demolition waste from the construction industry, has transformed into crucial apprehension of governments. In the recent past, substantial explorations have been accomplished to appreciate the distinct characteristics of concrete, employing recycled aggregates from construction and demolition waste. Geopolymer composite is a new cementitious material, and it appears to be a potential replacement for conventional cement concrete. This paper summarises the previous research concerning the utilisation of recycled aggregate as a partial or complete supplants for conventional aggregates in geopolymer concrete. The influence of recycled aggregate addition on the fresh and hardened properties of geopolymer concrete is comprehensively reviewed in this paper. The studies suggest significant improvement in the workability on addition of recycled aggregates to geopolymer concrete. However, the addition results in increased water absorption and sorptivity.

101 citations


Journal ArticleDOI
TL;DR: In this paper , the authors present a new material that can be used as a partial substitute for cement in the production of ultra high performance concrete (UHPC), which is an industrial waste product of ferrosilicon (FS) alloy, available as furnace slag.

98 citations


Journal ArticleDOI
TL;DR: In this article , the authors reviewed the literature discussing the use of recycled glass waste in concrete as a partial or complete replacement for aggregates, focusing on the effect of recycling glass waste on the fresh and mechanical properties of concrete.
Abstract: The safe disposal of an enormous amount of waste glass (WG) in several countries has become a severe environmental issue. In contrast, concrete production consumes a large amount of natural resources and contributes to environmental greenhouse gas emissions. It is widely known that many kinds of waste may be utilized rather than raw materials in the field of construction materials. However, for the wide use of waste in building construction, it is necessary to ensure that the characteristics of the resulting building materials are appropriate. Recycled glass waste is one of the most attractive waste materials that can be used to create sustainable concrete compounds. Therefore, researchers focus on the production of concrete and cement mortar by utilizing waste glass as an aggregate or as a pozzolanic material. In this article, the literature discussing the use of recycled glass waste in concrete as a partial or complete replacement for aggregates has been reviewed by focusing on the effect of recycled glass waste on the fresh and mechanical properties of concrete.

84 citations


Journal ArticleDOI
TL;DR: In this article, the authors integrated carbon-negative rice husk biochar and yard waste biochar (YBC) as green additives into the binder for low carbon stabilization/solidification (S/S) of municipal solid waste incineration (MSWI) fly ash.

77 citations


Journal ArticleDOI
Xi Jiang, Rui Xiao, Yun Bai, Baoshan Huang, Yuetan Ma 
TL;DR: In this paper , the effect of using waste glass powder (WGP) as an ordinary Portland cement (OPC) supplementary material on the paste specimens at ambient temperature and after exposure to high temperatures (800 °C, 1000 °C and 1200 °C).

76 citations


Journal ArticleDOI
TL;DR: In this article , the authors integrated carbon-negative rice husk biochar and yard waste biochar (YBC) as green additives into the binder for low carbon stabilization/solidification (S/S) of municipal solid waste incineration (MSWI) fly ash.

69 citations


Journal ArticleDOI
TL;DR: Wang et al. as mentioned in this paper developed a new low-carbon ecological ultra-high-performance concrete with high strength and excellent durability, namely sulfoaluminate cement-based reactive powder concrete (SACRPC).

68 citations


Journal ArticleDOI
TL;DR: In this article , a model for the estimation of the compressive strength of concretes incorporating metakaolin is developed and parametrically evaluated, using soft computing techniques, using a database of 867 experimental specimens.

64 citations


Journal ArticleDOI
TL;DR: In this paper, an innovative magnesium oxysulfate cement (MOSC) binder was designed for stabilization/solidification (S/S) of MSWI fly ash, focusing on the interactions between MOSC binder and typical metallic cations (Pb2+)/oxyanions (AsO33-).

64 citations


Journal ArticleDOI
Keiko Sasaki1
TL;DR: In this paper , an innovative magnesium oxysulfate cement (MOSC) binder was designed for stabilization/solidification (S/S) of MSWI fly ash, focusing on the interactions between MOSC binder and typical metallic cations (Pb2+)/oxyanions (AsO33-).

64 citations


Journal ArticleDOI
TL;DR: In this article , the effect of waste glass on the mechanical properties of concrete was examined by conducting a series of compressive strength, splitting tensile strength and flexural strength tests, where waste glass powder was first used as a partial replacement for cement and six different ratios of WGP were utilized in concrete production.
Abstract: In this study, the effect of waste glass on the mechanical properties of concrete was examined by conducting a series of compressive strength, splitting tensile strength and flexural strength tests. According to this aim, waste glass powder (WGP) was first used as a partial replacement for cement and six different ratios of WGP were utilized in concrete production: 0%, 10%, 20%, 30%, 40%, and 50%. To examine the combined effect of different ratios of WGP on concrete performance, mixed samples (10%, 20%, 30%) were then prepared by replacing cement, and fine and coarse aggregates with both WGP and crashed glass particles. Workability and slump values of concrete produced with different amounts of waste glass were determined on the fresh state of concrete, and these properties were compared with those of plain concrete. For the hardened concrete, 150 mm × 150 mm × 150 mm cubic specimens and cylindrical specimens with a diameter of 100 mm and a height of 200 mm were tested to identify the compressive strength and splitting tensile strength of the concrete produced with waste glass. Next, a three-point bending test was carried out on samples with dimensions of 100 × 100 × 400 mm, and a span length of 300 mm to obtain the flexure behavior of different mixtures. According to the results obtained, a 20% substitution of WGP as cement can be considered the optimum dose. On the other hand, for concrete produced with combined WGP and crashed glass particles, mechanical properties increased up to a certain limit and then decreased owing to poor workability. Thus, 10% can be considered the optimum replacement level, as combined waste glass shows considerably higher strength and better workability properties. Furthermore, scanning electron microscope (SEM) analysis was performed to investigate the microstructure of the composition. Good adhesion was observed between the waste glass and cementitious concrete. Lastly, practical empirical equations have been developed to determine the compressive strength, splitting tensile strength, and flexure strength of concrete with different amounts of waste glass. Instead of conducting an experiment, these strength values of the concrete produced with glass powder can be easily estimated at the design stage with the help of proposed expressions.

Journal ArticleDOI
TL;DR: In this paper , the influence of two types of Magnesia expansion agent on the hydration, as well as the shrinkage behavior of LHP cement-based materials, were studied via pore structural and fractal analysis.
Abstract: Currently, low heat Portland (LHP) cement is widely used in mass concrete structures. The magnesia expansion agent (MgO) can be adopted to reduce the shrinkage of conventional Portland cement-based materials, but very few studies can be found that investigate the influence of MgO on the properties of LHP cement-based materials. In this study, the influences of two types of MgO on the hydration, as well as the shrinkage behavior of LHP cement-based materials, were studied via pore structural and fractal analysis. The results indicate: (1) The addition of reactive MgO (with a reactivity of 50 s and shortened as M50 thereafter) not only extends the induction stage of LHP cement by about 1–2 h, but also slightly increases the hydration heat. In contrast, the addition of weak reactive MgO (with a reactivity of 300 s and shortened as M300 thereafter) could not prolong the induction stage of LHP cement. (2) The addition of 4 wt.%–8 wt.% MgO (by weight of binder) lowers the mechanical property of LHP concrete. Higher dosages of MgO and stronger reactivity lead to a larger reduction in mechanical properties at all of the hydration times studied. M300 favors the strength improvement of LHP concrete at later ages. (3) M50 effectively compensates the shrinkage of LHP concrete at a much earlier time than M300, whereas M300 compensates the long-term shrinkage more effectively than M50. Thus, M300 with an optimal dosage of 8 wt.% is suggested to be applied in mass LHP concrete structures. (4) The addition of M50 obviously refines the pore structures of LHP concrete at 7 days, whereas M300 starts to refine the pore structure at around 60 days. At 360 days, the concretes containing M300 exhibits much finer pore structures than those containing M50. (5) Fractal dimension is closely correlated with the pore structure of LHP concrete. Both pore structure and fractal dimension exhibit weak (or no) correlations with shrinkage of LHP concrete.

Journal ArticleDOI
TL;DR: In this article , the effect of ammonium nitrate (NH4NO3) on the unity weight and strength of glass mortar by performing experimental tests was studied. But the experimental results showed that the effect on the density of mortar containing recycled glass powder (GP) is less critical than that of conventional mortar.

Journal ArticleDOI
TL;DR: In this article , the authors developed a model to analyze the theoretical CO 2 emissions of alternative low-carbon cements, which can be used to calculate the fuel consumed in the production of new low carbon cements based on the theory of heat balance.

Journal ArticleDOI
TL;DR: In this article , the fracture toughness of quaternary binder concretes has been evaluated using the Digital Image Correlation (DIC) measurements and visual analysis of cracks propagation.

Journal ArticleDOI
TL;DR: In this article , expanded perlite and fine-sized waste glass sand were used as the main aggregates in concrete mixes to reduce the pore network connectivity and increase the insulation properties of foam concrete.

Journal ArticleDOI
TL;DR: In this paper , ground glass powder and crushed waste glass were used to replace coarse and fine aggregates, and significant progress in the tensile strength of the concrete was achieved by 14%, while the waste glass used as a fractional replacement for the fine aggregate.
Abstract: In this study, ground glass powder and crushed waste glass were used to replace coarse and fine aggregates. Within the scope of the study, fine aggregate (FA) and coarse aggregate (CA) were changed separately with proportions of 10%, 20%, 40%, and 50%. According to the mechanical test, including compression, splitting tensile, and flexural tests, the waste glass powder creates a better pozzolanic effect and increases the strength, while the glass particles tend to decrease the strength when they are swapped with aggregates. As observed in the splitting tensile test, noteworthy progress in the tensile strength of the concrete was achieved by 14%, while the waste glass used as a fractional replacement for the fine aggregate. In samples where glass particles were swapped with CA, the tensile strength tended to decrease. It was noticed that with the adding of waste glass at 10%, 20%, 40%, and 50% of FA swapped, the increase in flexural strength was 3.2%, 6.3%, 11.1%, and 4.8%, respectively, in amount to the reference one (6.3 MPa). Scanning electron microscope (SEM) analysis consequences also confirm the strength consequences obtained from the experimental study. While it is seen that glass powder provides better bonding with cement with its pozzolanic effect and this has a positive effect on strength consequences, it is seen that voids are formed in the samples where large glass pieces are swapped with aggregate and this affects the strength negatively. Furthermore, simple equations using existing data in the literature and the consequences obtained from the current study were also developed to predict mechanical properties of the concrete with recycled glass for practical applications. Based on findings obtained from our study, 20% replacement for FA and CA with waste glass is recommended.

Journal ArticleDOI
TL;DR: In this article , the effects of multilayer graphene (MLG) on the hydration, microstructure, and mechanical properties of ultra-high-performance concrete were investigated.
Abstract: Multi-layer graphene (MLG) has excellent mechanical properties and a unique stacked structure. In this paper, sulphoaluminate cement replaced ordinary portland cement to prepare low-carbon ecological ultra-high-performance-concrete (UHPC); the effects of MLG on the hydration, microstructure, and mechanical properties of UHPC were investigated, revealing the hydration mechanism and reinforcing mechanism of MLG on UHPC. Results show that adding MLG can significantly enhance the macro performance of UHPC. When the MLG content is 0.08%, UHPC has better macro performance. Compared with the M0 group, the flexural strength and compressive strength of the M3 group increased by 31.6%, 35.3%, 43.3%, 50.9%, and 9.5%, 13.5%, 22.2%, 21.7% after curing for 1 d, 7 d, 28 d, and 56 d, respectively. We quantitatively characterized the content of hydration product changes in UHPC. Various characterization analyses showed that the adsorption effect and nucleation effect of MLG promoted the hydrolysis and ions exchange of Ca2+ and Al3+, which provided sites for the growth of hydration products and accelerated the hydration process of cement, forming more hydration products, including AFt (ettringite) and AH3 (gibbsite). AFt, AH3, and MLG are closely connected, filling the pores and reducing the porosity of the matrix, optimizing the pore structure, and the medium and large pores transformed into micro-nano pores. Revealing the multi-level reinforcing mechanism, namely hydration products (AFt, AH3) and MLG filling the pores; MLG prevented the extension of micro-cracks and changed micro-cracks development path through filling effect, deflection effect, pulling out, and bridging effect.

Journal ArticleDOI
TL;DR: In this article , the authors reviewed the mechanisms that lead to concrete deterioration due to the coupling action of FT cycles and other factors, such as the use of air-entraining agents, the incorporation of fibers and the replacement of cement with pozzolanic cementitious materials.

Journal ArticleDOI
TL;DR: In this paper , the authors provide a comprehensive summary of recent developments on the use of nanomaterials as a performance enhancer in cement/geopolymer concrete. And they confirm the feasibility of using the nano-materials in cement concrete, with the required properties of building materials.
Abstract: In past decades, researchers have tried to improve the durability of concrete by integrating supplementary cementitious materials into concrete. Recent advancements in the field of nano-engineered concrete have reported that nanomaterials significantly improve the mechanical and durability properties of concrete. This paper provides a comprehensive summary of recent developments on the use of nanomaterials as a performance enhancer in cement/geopolymer concrete. Many significant correlations associated with the reinforcement of cementitious matrices using nano-TiO2, nano-Fe2O3, nanoclay/metakaolin, and nano-CaCO3 were studied. Performance aspects such as fresh properties, microstructure, mechanical and durability characteristics, and the influence of various particle sizes have been reviewed. The findings from this review confirm the feasibility of using the nanomaterials in cement concrete, with the required properties of building materials. It is also expected that this review provides better insight into using nanomaterials in concrete for the benefit of academic and fundamental research and promotes its practical application in the construction industry.

Journal ArticleDOI
TL;DR: In this paper , the influence of the magnesium-phosphorus molar (M/P) ratio and water-to-binder (W/B) ratio on the hydration product is explored by the thermodynamic simulation.
Abstract: Magnesium phosphate cement (MPC) paste is hardened by the acid–base reaction between magnesium oxide and phosphate. This work collects and evaluates the thermodynamic data at 25 ℃ and a pressure of 0.1 MPa and establishes the hydration reaction model of MPC pastes. The influence of the magnesium–phosphorus molar (M/P) ratio and water-to-binder (W/B) ratio on the hydration product is explored by the thermodynamic simulation. Following this, the initial and ultimate states of the hydration state of MPC pastes are visualized, and the porosity of different pastes as well as fractal analysis are presented. The result shows that a small M/P ratio is beneficial for the formation of main hydration products. The boric acid acts as a retarder, has a significant effect on lowering the pH of the paste, and slows down the formation of hydration products. After the porosity comparison, it can be concluded that the decreasing of M/P and W/B ratios helps reduce porosity. In addition, the fractal dimension Df of MPC pastes is positively proportional to the porosity, and small M/P ratios as well as small W/B ratios are beneficial for reducing the Df of MKPC pastes.

Journal ArticleDOI
TL;DR: In this article , the most widely used accelerators for cast and sprayed concrete are reviewed, focusing on their influence on the aluminate and silicate reaction of cement hydration as well as the setting and hardening depending on the dosage of the admixture.

Journal ArticleDOI
TL;DR: In this article , the authors investigated the effect of using sugarcane leaf ash (SLA) as a pozzolanic material on the properties of UHSC and showed the efficiency of using SLA as a partial substitute of the 20% of cement weight with mechanical properties and durability higher than the mechanical properties of the reference mixture.
Abstract: The global expansion of agricultural production increases agricultural waste ash (AWA). Accordingly, AWA should be disposed to preserve the environment. This study focuses on using AWA as a partial substitute for cement to produce ultrahigh-strength concrete (UHSC). This research investigated the effect of using sugarcane leaf ash (SLA) as a pozzolanic material on the properties of UHSC. The cement replacement rates by SLA were 10%, 20% and 30% by weight. SLA was heat-treated at 400, 500, 600, 700 and 800 °C for 2 h to improve its physical and chemical properties. The effects of the heat-treated SLA on UHSC mechanical properties such as, compressive strength, split tensile strength, flexural strength and modulus of elasticity, were studied. The effects of heat-treated SLA on UHSC durability such as, water permeability, chloride penetration and sorptivity of UHSC were also investigated. In addition to, microstructure analysis of several UHSC mixtures was presented. Results showed the efficiency of SLA as a partial substitute of the 20% of cement weight with mechanical properties and durability higher than the mechanical properties and durability of the reference mixture. Compared with the reference mixture, the heat-treated SLA used as a partial substitute generally improved all properties. The UHSC containing SLA heat-treated at 700 °C and a 20% substitution rate achieved the best results of 162.5, 17.78, 24.05 and 55,820 MPa for compressive strength, tensile strength, bending strength and modulus of elasticity at test age of 28 days.

Journal ArticleDOI
TL;DR: In this paper , the authors proposed a novel model of aeolian sand-cement-modified gasification slag-paste backfill (ACGPB), which realized the safe disposal and resource utilization of hazardous solid wastes.

Journal ArticleDOI
TL;DR: In this article , a comprehensive study of the microstructural properties of ultra-high performance concrete (UHPC) provides essential information about the underlying causes of its mechanical properties.
Abstract: A comprehensive study of the microstructural properties of ultra-high performance concrete (UHPC) provides essential information about the underlying causes of its mechanical properties. The present article reviews studies that used X-ray diffraction (XRD), scanning electron microscope (SEM), mercury intrusion measurement (MIP), energy-dispersive X-ray spectroscopy (EDS), and thermal analysis to investigate the microstructure of UHPC containing silica sand and different cementitious materials as partial replacement of cement, including silica fume, zeolite, ground-granulated blast furnace slags, lithium slag, metakaolin, limestone powder, and rice husk ash. Moreover, the importance of microstructural analyses for expressing the cause of optimal percentages of different cement replacements, determining the best type of pozzolan, the appropriate sand in UHPC, and the appropriate curing method to create the best mechanical properties were highlighted. The results proved the rather small transition zone in the UHPC indicating a strong bond between the cement paste and the aggregates, and a very dense internal structure.

Journal ArticleDOI
TL;DR: In this article , low-carbon cement with a main phase of γ-C 2 S exhibits excellent carbonation activity in the presence of moisture, but its sintering temperature in a conventional furnace is about 1400 °C, which consumes a huge amount of energy.

Journal ArticleDOI
TL;DR: In this article , a review of ground-granulated blast-furnace slag (GGBS) manufacturing and its physical, chemical and hydraulic activity and heat of hydration are thoroughly discussed.
Abstract: In the last few decades, the concrete industry has been massively expanded with the adoption of various kinds of binding materials. As a substitute to cement and in an effort to relieve ecofriendly difficulties linked with cement creation, the utilization of industrial waste as cementitious material can sharply reduce the amount of trash disposed of in lakes and landfills. With respect to the mechanical properties, durability and thermal behavior, ground-granulated blast-furnace slag (GGBS) delineates a rational way to develop sustainable cement and concrete. Apart from environmental benefits, the replacement of cement by GGBS illustrates an adequate way to mitigate the economic impact. Although many researchers concentrate on utilizing GGBS in concrete production, knowledge is scattered, and additional research is needed to better understand relationships among a wide spectrum of key questions and to more accurately determine these preliminary findings. This work aims to shed some light on the scientific literature focusing on the use and effectiveness of GGBS as an alternative to cement. First and foremost, basic information on GGBS manufacturing and its physical, chemical and hydraulic activity and heat of hydration are thoroughly discussed. In a following step, fresh concrete properties, such as flowability and mechanical strength, are examined. Furthermore, the durability of concrete, such as density, permeability, acid resistance, carbonation depth and dry shrinkage, are also reviewed and interpreted. It can be deduced that the chemical structure of GGBS is parallel to that of cement, as it shows the creditability of being partially integrated and overall suggests an alternative to Ordinary Portland Cement (OPC). On the basis of such adjustments, the mechanical strength of concrete with GGBS has shown an increase, to a certain degree; however, the flowability of concrete has been reduced. In addition, the durability of concrete containing GGBS cement is shown to be superior. The optimum percentage of GGBS is an essential aspect of better performance. Previous studies have suggested different optimum percentages of GGBS varying from 10 to 20%, depending on the source of GGBS, concrete mix design and particle size of GGBS. Finally, the review also presents some basic process improvement tips for future generations to use GGBS in concrete.

Journal ArticleDOI
TL;DR: In this paper , the performance of waste marble powder as a partial replacement for cement is examined with the aim of achieving more sustainable concrete, where a total of 15 specimens were manufactured and then tested to examine the bending behavior.
Abstract: The performance of waste marble powder as a partial replacement for cement is examined with the aim to achieve more sustainable concrete. Pursuant to this goal, a total of 15 specimens were manufactured and then tested to examine the bending behavior. The effects of longitudinal reinforcement ratio and waste marble powder ratio were selected as variables. The experimental results showed that different proportions of tension reinforcement and waste marble powder had different crack and bending impacts on reinforced concrete beams. As the waste marble powder amount in the concrete mixture is increased from 0% to 40%, it was detected that the crack type changes from a shear crack from to a flexural crack as the amount of waste marble powder increases in the mixing ratio. The experimental findings revealed that the waste marble powder can be successfully used as 10% of the partial replacement of cement. Increasing the waste marble powder ratio by more than 10% can significantly decrease the capacity of the beams, especially when longitudinal reinforcement ratio is high. The influence of waste marble as partial replacement on the capacity decreases as the longitudinal reinforcement ratio decreases. Therefore, 10%–20% marble waste can be utilized as a replacement for cement when the longitudinal reinforcement ratio is close to the balanced ratio and more than 20% waste marble ratio should be avoided for any cases.

Journal ArticleDOI
TL;DR: In this article , waste glass (WG) was used as a filler material that filled the voids between RCA to offset its negative impact on concrete performance, and a step towards sustainable concrete was made by utilizing recycled concrete aggregate (RCA) as a coarse aggregate.
Abstract: The current practice of concrete is thought to be unsuitable because it consumes large amounts of cement, sand, and aggregate, which causes depletion of natural resources. In this study, a step towards sustainable concrete was made by utilizing recycled concrete aggregate (RCA) as a coarse aggregate. However, researchers show that RCA causes a decrease in the performance of concrete due to porous nature. In this study, waste glass (WG) was used as a filler material that filled the voids between RCA to offset its negative impact on concrete performance. The substitution ratio of WG was 10, 20, or 30% by weight of cement, and RCA was 20, 40, and 60% by weight of coarse aggregate. The slump cone test was used to assess the fresh property, while compressive, split tensile, and punching strength were used to assess the mechanical performance. Test results indicated that the workability of concrete decreased with substitution of WG and RCA while mechanical performance improved up to a certain limit and then decreased due to lack of workability. Furthermore, a statical tool response surface methodology was used to predict various strength properties and optimization of RCA and WG.

Journal ArticleDOI
TL;DR: A systematic and scientific experimental study was conducted, in which 29 concrete mixes with steel slag partially or totally replacing natural aggregates and FA/SF partially replacing cement in an equal volume were prepared as discussed by the authors .