The application of advanced binder consisting of limestone, calcined clay and cement (LC3) promotes the development of low-carbon engineering cementitious composites (ECC). In order to improve the comprehensive properties of LC3-ECC, this paper investigates the feasibility of using nano CaCO3 (NC) to replace the limestone powder up to 20 % for LC3-ECC preparation through rheology and mechanical tests along with the micro-design calculation and microstructure analysis. Results indicate that the yield stress and plastic viscosity of LC3-ECC are largely improved with increasing NC replacement rate. Meanwhile, the compressive, flexural and tensile strengths of LC3-ECC with NC raise firstly and then decline, while the strengths are maximum at NC replacement rate of 5 % but the tensile strain capacity remains at 2.3 %. The hydration promotion effect and pore structure refinement effect of NC particles improve the mechanical strength of LC3-ECC, but the performance degradation occurs when the replacement rate of the NC exceeds 10 %. In micromechanics, the fibre bridging stress of LC3-ECC reinforced by NC with replacement rate of 5 % decreases by 18.5 % compared to that of without NC, but it grows with the increasing NC replacement rate. In combination with fresh, hardened and microstructure behaviour, LC3-ECC exhibits the optimum mechanical behaviour with the NC replacement rate of 10 %–15 %.
{"title":"Rheology and mechanical properties of limestone calcined clay based engineered cementitious composites with nano CaCO3","authors":"Yuting Wang , Meng Chen , Tong Zhang , Mingzhong Zhang","doi":"10.1016/j.cemconcomp.2025.105923","DOIUrl":"10.1016/j.cemconcomp.2025.105923","url":null,"abstract":"<div><div>The application of advanced binder consisting of limestone, calcined clay and cement (LC<sup>3</sup>) promotes the development of low-carbon engineering cementitious composites (ECC). In order to improve the comprehensive properties of LC<sup>3</sup>-ECC, this paper investigates the feasibility of using nano CaCO<sub>3</sub> (NC) to replace the limestone powder up to 20 % for LC<sup>3</sup>-ECC preparation through rheology and mechanical tests along with the micro-design calculation and microstructure analysis. Results indicate that the yield stress and plastic viscosity of LC<sup>3</sup>-ECC are largely improved with increasing NC replacement rate. Meanwhile, the compressive, flexural and tensile strengths of LC<sup>3</sup>-ECC with NC raise firstly and then decline, while the strengths are maximum at NC replacement rate of 5 % but the tensile strain capacity remains at 2.3 %. The hydration promotion effect and pore structure refinement effect of NC particles improve the mechanical strength of LC<sup>3</sup>-ECC, but the performance degradation occurs when the replacement rate of the NC exceeds 10 %. In micromechanics, the fibre bridging stress of LC<sup>3</sup>-ECC reinforced by NC with replacement rate of 5 % decreases by 18.5 % compared to that of without NC, but it grows with the increasing NC replacement rate. In combination with fresh, hardened and microstructure behaviour, LC<sup>3</sup>-ECC exhibits the optimum mechanical behaviour with the NC replacement rate of 10 %–15 %.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"157 ","pages":"Article 105923"},"PeriodicalIF":10.8,"publicationDate":"2025-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142935162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-07DOI: 10.1016/j.cemconcomp.2025.105925
Dingqiang Fan , Jian-Xin Lu , Xue-Sen Lv , Takafumi Noguchi , Rui Yu , Chi Sun Poon
This study introduces a novel strategy for carbon capture and utilization by incorporating CO2 into foams to develop CO2 foam concrete (CFC) with high performance. A conceptual design approach for CFC was first proposed by incorporating tailor-made CO2 foam into an optimized cement-based paste. The engineered CO2 foam exhibited fine size and good stability, but increasing CO2 concentration decreased stability. Then, the CO2 foam was used to fabricate CFC with high strength (about twice that of normal foam concrete at a similar density), excellent durability (comparable to normal concrete), and low thermal conductivity. Moreover, it was demonstrated that CO2 foam induced positive internal carbonation effects to further enhance the CFC performance. These effects included promoting cement hydration efficiency and generating CaCO3 on the foam wall for strength enhancement. Also, the rational use of CO2 foams optimized the CFC pore structures, including reducing porosity, refining pore size, and improving pore uniformity. The CFC exhibited exceptional carbon capture, sequestering 87 kg of CO2 per m3 of concrete by internal and external carbonations (active carbon reduction), and could reduce electricity consumption and the corresponding carbon emissions (indirect carbon reduction). This innovative material offers a promising pathway towards sustainable construction and carbon neutrality.
{"title":"Carbon capture and storage CO2 foam concrete towards higher performance: Design, preparation and characteristics","authors":"Dingqiang Fan , Jian-Xin Lu , Xue-Sen Lv , Takafumi Noguchi , Rui Yu , Chi Sun Poon","doi":"10.1016/j.cemconcomp.2025.105925","DOIUrl":"10.1016/j.cemconcomp.2025.105925","url":null,"abstract":"<div><div>This study introduces a novel strategy for carbon capture and utilization by incorporating CO<sub>2</sub> into foams to develop CO<sub>2</sub> foam concrete (CFC) with high performance. A conceptual design approach for CFC was first proposed by incorporating tailor-made CO<sub>2</sub> foam into an optimized cement-based paste. The engineered CO<sub>2</sub> foam exhibited fine size and good stability, but increasing CO<sub>2</sub> concentration decreased stability. Then, the CO<sub>2</sub> foam was used to fabricate CFC with high strength (about twice that of normal foam concrete at a similar density), excellent durability (comparable to normal concrete), and low thermal conductivity. Moreover, it was demonstrated that CO<sub>2</sub> foam induced positive internal carbonation effects to further enhance the CFC performance. These effects included promoting cement hydration efficiency and generating CaCO<sub>3</sub> on the foam wall for strength enhancement. Also, the rational use of CO<sub>2</sub> foams optimized the CFC pore structures, including reducing porosity, refining pore size, and improving pore uniformity. The CFC exhibited exceptional carbon capture, sequestering 87 kg of CO<sub>2</sub> per m<sup>3</sup> of concrete by internal and external carbonations (active carbon reduction), and could reduce electricity consumption and the corresponding carbon emissions (indirect carbon reduction). This innovative material offers a promising pathway towards sustainable construction and carbon neutrality.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"157 ","pages":"Article 105925"},"PeriodicalIF":10.8,"publicationDate":"2025-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142935161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-06DOI: 10.1016/j.cemconcomp.2025.105922
Yanjie Tang , Katrin Schollbach , Sieger van der Laan , Wei Chen
This study investigates the hydration of basic oxygen furnace (BOF) slag activated by dipotassium hydrogen phosphate (DKP) up to 3 wt%. The findings reveal that DKP-activated BOF slag pastes exhibit improved strength, leaching behavior, and carbonation resistance. DKP-activated BOF slag pastes facilitate the completion of the main exothermic reaction within 3 days. Increasing DKP from 1 to 3 wt% extends the induction period while enhancing overall hydration heat. This is attributed to the consumption of C2S and brownmillerite, and the formation of hydrogarnet, C-S-H gel, and layered double hydroxides (LDHs). Concomitantly, porosity reduces from 40.73 to 22.36 %, leading to significant strength gaining from 1.9 to 42.5 MPa over 28 days. Moreover, DKP-containing samples exhibit satisfactory carbonation resistance and limited heavy metal leaching, complying with the Dutch Soil Quality Decree (SQD). The study highlights the potential of phosphate activation to enhance the durability and environmental performance of BOF slag-based materials.
{"title":"Activation of BOF slag with dipotassium hydrogen phosphate: Enhancing hydration, carbonation resistance, and heavy metal leaching","authors":"Yanjie Tang , Katrin Schollbach , Sieger van der Laan , Wei Chen","doi":"10.1016/j.cemconcomp.2025.105922","DOIUrl":"10.1016/j.cemconcomp.2025.105922","url":null,"abstract":"<div><div>This study investigates the hydration of basic oxygen furnace (BOF) slag activated by dipotassium hydrogen phosphate (DKP) up to 3 wt%. The findings reveal that DKP-activated BOF slag pastes exhibit improved strength, leaching behavior, and carbonation resistance. DKP-activated BOF slag pastes facilitate the completion of the main exothermic reaction within 3 days. Increasing DKP from 1 to 3 wt% extends the induction period while enhancing overall hydration heat. This is attributed to the consumption of C<sub>2</sub>S and brownmillerite, and the formation of hydrogarnet, C-S-H gel, and layered double hydroxides (LDHs). Concomitantly, porosity reduces from 40.73 to 22.36 %, leading to significant strength gaining from 1.9 to 42.5 MPa over 28 days. Moreover, DKP-containing samples exhibit satisfactory carbonation resistance and limited heavy metal leaching, complying with the Dutch Soil Quality Decree (SQD). The study highlights the potential of phosphate activation to enhance the durability and environmental performance of BOF slag-based materials.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"157 ","pages":"Article 105922"},"PeriodicalIF":10.8,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142928992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-06DOI: 10.1016/j.cemconcomp.2025.105927
Qi Zhang , Pan Feng , Xuyan Shen , Yuxi Cai , Houru Zhen , Zhichao Liu
Maximizing the use of solid wastes to replace energy-intensive cement while maintaining the comparable mechanical properties is a promising strategy for developing negative carbon building materials. In this paper, full steel slag/carbide slag blocks were prepared by pressing and subsequent carbonation to enhance mechanical properties and capture CO2. The evolution of carbonation degree and compressive strength with varying liquid to solid ratios and carbonation durations were characterized, followed by a comparative analysis of carbonation strengthening mechanisms. The results show that carbonation significantly improves compressive strengths, exhibiting a linear relationship between carbonation degree and compressive strength. The maximum carbonation degrees and compressive strengths achieved were 24.56 % and 79.68 MPa for full steel slag blocks, and 64.46 %, 44.64 MPa for full carbide slag blocks, respectively. Although the maximum carbonation degree of full steel slag blocks is only about one-third of that of the full carbide slag blocks, their superior compressive strength can be attributed to denser microstructures, stronger bonding properties between steel slag particles and carbonated products, and a larger effective elastic modulus. This study provides a new insight into the carbonation strengthening mechanisms based on the inherent properties of different materials and introduces a novel concept for creating high-performance, eco-friendly building materials.
{"title":"Comparative analysis of carbonation strengthening mechanisms in full solid waste materials: Steel slag vs. carbide slag","authors":"Qi Zhang , Pan Feng , Xuyan Shen , Yuxi Cai , Houru Zhen , Zhichao Liu","doi":"10.1016/j.cemconcomp.2025.105927","DOIUrl":"10.1016/j.cemconcomp.2025.105927","url":null,"abstract":"<div><div>Maximizing the use of solid wastes to replace energy-intensive cement while maintaining the comparable mechanical properties is a promising strategy for developing negative carbon building materials. In this paper, full steel slag/carbide slag blocks were prepared by pressing and subsequent carbonation to enhance mechanical properties and capture CO<sub>2</sub>. The evolution of carbonation degree and compressive strength with varying liquid to solid ratios and carbonation durations were characterized, followed by a comparative analysis of carbonation strengthening mechanisms. The results show that carbonation significantly improves compressive strengths, exhibiting a linear relationship between carbonation degree and compressive strength. The maximum carbonation degrees and compressive strengths achieved were 24.56 % and 79.68 MPa for full steel slag blocks, and 64.46 %, 44.64 MPa for full carbide slag blocks, respectively. Although the maximum carbonation degree of full steel slag blocks is only about one-third of that of the full carbide slag blocks, their superior compressive strength can be attributed to denser microstructures, stronger bonding properties between steel slag particles and carbonated products, and a larger effective elastic modulus. This study provides a new insight into the carbonation strengthening mechanisms based on the inherent properties of different materials and introduces a novel concept for creating high-performance, eco-friendly building materials.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"157 ","pages":"Article 105927"},"PeriodicalIF":10.8,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142935085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-06DOI: 10.1016/j.cemconcomp.2025.105921
Brahim Mazian , Giana Almeida , Nils Frantz , Patrick Perré
Lime-hemp concrete (LHC) emerges as a sustainable building material due to its low embodied energy, carbon storage capabilities, and interesting properties for both winter and summer comfort. However, a comprehensive understanding of its moisture behavior is pivotal for its development and application in construction. This study investigates the moisture sorption behavior and isotherm characteristics of LHC across four formulations varying in density (321–478 kg/m³) and binder/particle weight ratios (BP = 1 and 2). Using a strict equilibrium criterion, over 3000 h of Dynamic Vapor Sorption (DVS), experiments revealed some formulations failed to reach equilibrium during adsorption at RH levels above 60 %, indicating irreversible processes characterized by offsets in equilibrium moisture content (EMC) at 0 % RH after a complete cycle. These phenomena were attributed to insufficient water availability during mixing and/or excessive compaction. Formulations with a higher weight ratio (B/P = 2) and significant compaction, such as BP2_420, exhibited the highest desorption offset (7.5 % EMC), while those with a lower B/P weight ratio (B/P = 1), such as BP1_379, showed reduced offsets below 2 %, due to better water distribution. The study also showed that reversible sorption behavior, corrected for offsets, could be accurately described using the Guggenheim-Anderson-de Boer (GAB) model. Finally, the rule of mixtures reliably predicted sorption isotherms by combining the GAB parameters of hemp shive particles and binder, with deviations limited to a maximum error of 2.3 %.
{"title":"In-depth analysis of Lime-hemp concrete and water vapor interactions: Effect of water default and prediction of the sorption behavior","authors":"Brahim Mazian , Giana Almeida , Nils Frantz , Patrick Perré","doi":"10.1016/j.cemconcomp.2025.105921","DOIUrl":"10.1016/j.cemconcomp.2025.105921","url":null,"abstract":"<div><div>Lime-hemp concrete (LHC) emerges as a sustainable building material due to its low embodied energy, carbon storage capabilities, and interesting properties for both winter and summer comfort. However, a comprehensive understanding of its moisture behavior is pivotal for its development and application in construction. This study investigates the moisture sorption behavior and isotherm characteristics of LHC across four formulations varying in density (321–478 kg/m³) and binder/particle weight ratios (BP = 1 and 2). Using a strict equilibrium criterion, over 3000 h of Dynamic Vapor Sorption (DVS), experiments revealed some formulations failed to reach equilibrium during adsorption at RH levels above 60 %, indicating irreversible processes characterized by offsets in equilibrium moisture content (EMC) at 0 % RH after a complete cycle. These phenomena were attributed to insufficient water availability during mixing and/or excessive compaction. Formulations with a higher weight ratio (B/P = 2) and significant compaction, such as BP2_420, exhibited the highest desorption offset (7.5 % EMC), while those with a lower B/P weight ratio (B/P = 1), such as BP1_379, showed reduced offsets below 2 %, due to better water distribution. The study also showed that reversible sorption behavior, corrected for offsets, could be accurately described using the Guggenheim-Anderson-de Boer (GAB) model. Finally, the rule of mixtures reliably predicted sorption isotherms by combining the GAB parameters of hemp shive particles and binder, with deviations limited to a maximum error of 2.3 %.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"157 ","pages":"Article 105921"},"PeriodicalIF":10.8,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142928994","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-03DOI: 10.1016/j.cemconcomp.2025.105920
Ying Hua , Zhichao Zhang , Lu Yuan , Jueshi Qian , Yanfei Yue , Zhen Li , Xingwen Jia
The soluble phosphates in phosphogypsum (PG) are generally considered to hinder its utilization without pretreatments. This paper investigated the positive effect of soluble phosphates on the strength development of anhydrite calcined from PG at 800 °C for 1 h. PG, washed PG with different soluble phosphate contents, washed PG added with washed water, and flue gas desulfurization gypsum (FGD) were used to prepare anhydrite. The hydration degree and strength development of anhydrite were measured. The effect mechanism was explored by XRD, FTIR, and SEM. Results showed the 28-day strength decreased from 35.9 MPa to almost no strength when the soluble P2O5 content decreased from 0.7480 % to 0.0471 %. Soluble phosphates in PG would affect the microstructure of anhydrite particles, promoting the strength development, however, they did not affect the strength of anhydrite calcined from FGD. It is concluded that the soluble phosphates in PG are beneficial for manufacturing anhydrite, which is a promising utilization.
{"title":"Effect of soluble phosphate on strength development of anhydrite calcined from phosphogypsum","authors":"Ying Hua , Zhichao Zhang , Lu Yuan , Jueshi Qian , Yanfei Yue , Zhen Li , Xingwen Jia","doi":"10.1016/j.cemconcomp.2025.105920","DOIUrl":"10.1016/j.cemconcomp.2025.105920","url":null,"abstract":"<div><div>The soluble phosphates in phosphogypsum (PG) are generally considered to hinder its utilization without pretreatments. This paper investigated the positive effect of soluble phosphates on the strength development of anhydrite calcined from PG at 800 °C for 1 h. PG, washed PG with different soluble phosphate contents, washed PG added with washed water, and flue gas desulfurization gypsum (FGD) were used to prepare anhydrite. The hydration degree and strength development of anhydrite were measured. The effect mechanism was explored by XRD, FTIR, and SEM. Results showed the 28-day strength decreased from 35.9 MPa to almost no strength when the soluble P<sub>2</sub>O<sub>5</sub> content decreased from 0.7480 % to 0.0471 %. Soluble phosphates in PG would affect the microstructure of anhydrite particles, promoting the strength development, however, they did not affect the strength of anhydrite calcined from FGD. It is concluded that the soluble phosphates in PG are beneficial for manufacturing anhydrite, which is a promising utilization.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"157 ","pages":"Article 105920"},"PeriodicalIF":10.8,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142917111","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study explores the effect of polymer concentration on the dispersion of carbon nanotubes (CNTs) and the mechanical properties of cement-based materials via tests and molecular dynamics (MD) simulations. The results showed that all three polymers (ethylene-vinyl acetate (EVA), styrene-acrylate (SAE), and styrene-butadiene (SB) copolymers) significantly enhanced CNTs’ dispersion. The key factors driving this improvement are the coordination bond, H-bonds, π-π stacking, and van der Waals forces between the polymer and CNTs, which promote strong adsorption. This reduces the interaction energy generated among the CNTs. Additionally, the combined use of polymers and CNTs improves the mechanical properties of cement-based materials. First, the polymer films and CNTs formed a mesh structure inside the mortar, linking the hydration products, unhydrated cement particles, and aggregates. Secondly, the polymer films wrapped around the surface of the CNTs, which promoted the bond strength between the CNTs and calcium silicate hydrate. The synergistic effect between the polymers and CNTs is a promising approach for the development of advanced cementitious composites. The polymer promoted the dispersion of CNTs, whereas the CNTs compensated for the reduced compressive strength of the polymer-modified mortar and promoted hydration.
{"title":"Enhancing dispersion and mechanical properties of carbon nanotube-reinforced cement-based material using polymer emulsions","authors":"Shi-Wei Zhang , Ru Wang , Jiao-Long Zhang , Yong Yuan","doi":"10.1016/j.cemconcomp.2024.105910","DOIUrl":"10.1016/j.cemconcomp.2024.105910","url":null,"abstract":"<div><div>This study explores the effect of polymer concentration on the dispersion of carbon nanotubes (CNTs) and the mechanical properties of cement-based materials via tests and molecular dynamics (MD) simulations. The results showed that all three polymers (ethylene-vinyl acetate (EVA), styrene-acrylate (SAE), and styrene-butadiene (SB) copolymers) significantly enhanced CNTs’ dispersion. The key factors driving this improvement are the coordination bond, H-bonds, π-π stacking, and van der Waals forces between the polymer and CNTs, which promote strong adsorption. This reduces the interaction energy generated among the CNTs. Additionally, the combined use of polymers and CNTs improves the mechanical properties of cement-based materials. First, the polymer films and CNTs formed a mesh structure inside the mortar, linking the hydration products, unhydrated cement particles, and aggregates. Secondly, the polymer films wrapped around the surface of the CNTs, which promoted the bond strength between the CNTs and calcium silicate hydrate. The synergistic effect between the polymers and CNTs is a promising approach for the development of advanced cementitious composites. The polymer promoted the dispersion of CNTs, whereas the CNTs compensated for the reduced compressive strength of the polymer-modified mortar and promoted hydration.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"157 ","pages":"Article 105910"},"PeriodicalIF":10.8,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142924779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-03DOI: 10.1016/j.cemconcomp.2025.105919
Peiyun She , Shuhang Ye , Yiming Yao , Deju Zhu , Cong Lu
Textile reinforced engineered cementitious composite (TR-ECC) is a cementitious composite reinforced with continuous textiles and short random fibers, characterized by high tensile strength and strain capacity due to the successive formation of multiple fine cracks. Various tensile failure modes of TR-ECC have been extensively observed in experimental studies, while clear classification of these failure modes and their underlying mechanisms are to be explored. In this study, the novel established numerical model explains the causes of different tensile failure modes of TR-ECC based on the physical interactions among fibers, textiles, and the matrix. In the model, the tensile behavior of TR-ECC was innovatively simulated through a displacement-controlled loading method, while the stress field in different components was analyzed considering five phases: textiles, short fibers, matrix, textile/matrix interface, and fiber/matrix interface. With the proposed model, two distinct tensile failure modes (modes I and II) were identified. Simulated TR-ECC stress-strain curves (OP-I and OP-II) of both failure modes were acquired with adjustments of several key micro-properties on the same base curve under the guidance of the proposed model. OP-I achieved a tensile strength exceeding 9.5 MPa and maintained a strain capacity above 2 % due to secondary hardening after textile rupture, while OP-II exhibited stable multiple cracking with a lower peak strength of 7.2 MPa but a higher strain capacity exceeding 6 %. These two specific optimization strategies were proposed based on the model to address different material performance requirements, providing a framework for performance-driven design of TR-ECC to ensure optimal mechanical performance and durability.
{"title":"Micromechanical model and performance-driven design strategy for textile reinforced engineered cementitious composite (TR-ECC)","authors":"Peiyun She , Shuhang Ye , Yiming Yao , Deju Zhu , Cong Lu","doi":"10.1016/j.cemconcomp.2025.105919","DOIUrl":"10.1016/j.cemconcomp.2025.105919","url":null,"abstract":"<div><div>Textile reinforced engineered cementitious composite (TR-ECC) is a cementitious composite reinforced with continuous textiles and short random fibers, characterized by high tensile strength and strain capacity due to the successive formation of multiple fine cracks. Various tensile failure modes of TR-ECC have been extensively observed in experimental studies, while clear classification of these failure modes and their underlying mechanisms are to be explored. In this study, the novel established numerical model explains the causes of different tensile failure modes of TR-ECC based on the physical interactions among fibers, textiles, and the matrix. In the model, the tensile behavior of TR-ECC was innovatively simulated through a displacement-controlled loading method, while the stress field in different components was analyzed considering five phases: textiles, short fibers, matrix, textile/matrix interface, and fiber/matrix interface. With the proposed model, two distinct tensile failure modes (modes I and II) were identified. Simulated TR-ECC stress-strain curves (OP-I and OP-II) of both failure modes were acquired with adjustments of several key micro-properties on the same base curve under the guidance of the proposed model. OP-I achieved a tensile strength exceeding 9.5 MPa and maintained a strain capacity above 2 % due to secondary hardening after textile rupture, while OP-II exhibited stable multiple cracking with a lower peak strength of 7.2 MPa but a higher strain capacity exceeding 6 %. These two specific optimization strategies were proposed based on the model to address different material performance requirements, providing a framework for performance-driven design of TR-ECC to ensure optimal mechanical performance and durability.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"157 ","pages":"Article 105919"},"PeriodicalIF":10.8,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142924778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-02DOI: 10.1016/j.cemconcomp.2024.105905
Sharu Bhagavathi Kandy , Sebastian Remke , Thiyagarajan Ranganathan , Shubham Kiran Wani , Xiaodi Dai , Narayanan Neithalath , Aditya Kumar , Mathieu Bauchy , Edward Garboczi , Torben Gädt , Samanvaya Srivastava , Gaurav Sant
An inability to accurately control the rate and extent of solidification of cementitious suspensions is a major impediment to creating geometrically complex structural shapes via 3D printing. In this work, we have developed a thermoresponsive rapid stiffening system that will stiffen suspensions of minerals such as quartz, limestone, portlandite, and Ordinary Portland Cement (OPC) over a wide pH range. When exposed to trigger temperatures between 40 °C and 70 °C, the polymer binder system undergoes a thermally triggered free radical polymerization (FRP) reaction, leading to an ultrafast stiffening of the suspension at an average rate on the order of 1 kPa/s and achieving MPa-level strength in less than a minute. The cured composites exhibit flexural strength and strain capacity far greater than OPC-based composites ( 25 MPa, 1 %). We successfully demonstrated 3D printing using these engineered slurries, showcasing their thermal response, thermal latency, and printability, thereby validating our design approach and its potential for diverse applications. These thermoresponsive slurries facilitate freestyle printing, non-horizontal printing, and the creation of complex geometries with high overhangs. This approach provides a means to surmount the significant limitations of extrusion-based 3D printing using particulate suspensions and open up new possibilities in integrating design and production.
{"title":"Design and function of thermoresponsive-ultrafast stiffening suspension formulations for 3D printing","authors":"Sharu Bhagavathi Kandy , Sebastian Remke , Thiyagarajan Ranganathan , Shubham Kiran Wani , Xiaodi Dai , Narayanan Neithalath , Aditya Kumar , Mathieu Bauchy , Edward Garboczi , Torben Gädt , Samanvaya Srivastava , Gaurav Sant","doi":"10.1016/j.cemconcomp.2024.105905","DOIUrl":"10.1016/j.cemconcomp.2024.105905","url":null,"abstract":"<div><div>An inability to accurately control the rate and extent of solidification of cementitious suspensions is a major impediment to creating geometrically complex structural shapes via 3D printing. In this work, we have developed a thermoresponsive rapid stiffening system that will stiffen suspensions of minerals such as quartz, limestone, portlandite, and Ordinary Portland Cement (OPC) over a wide pH range. When exposed to trigger temperatures between 40 °C and 70 °C, the polymer binder system undergoes a thermally triggered free radical polymerization (FRP) reaction, leading to an ultrafast stiffening of the suspension at an average rate on the order of 1 kPa/s and achieving MPa-level strength in less than a minute. The cured composites exhibit flexural strength and strain capacity far greater than OPC-based composites (<span><math><mrow><msub><mi>σ</mi><mi>f</mi></msub></mrow></math></span> <span><math><mrow><mo>∼</mo></mrow></math></span> 25 MPa, <span><math><mrow><msub><mi>γ</mi><mi>f</mi></msub></mrow></math></span> <span><math><mrow><mo>></mo></mrow></math></span> 1 %). We successfully demonstrated 3D printing using these engineered slurries, showcasing their thermal response, thermal latency, and printability, thereby validating our design approach and its potential for diverse applications. These thermoresponsive slurries facilitate freestyle printing, non-horizontal printing, and the creation of complex geometries with high overhangs. This approach provides a means to surmount the significant limitations of extrusion-based 3D printing using particulate suspensions and open up new possibilities in integrating design and production.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"157 ","pages":"Article 105905"},"PeriodicalIF":10.8,"publicationDate":"2025-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142912361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-30DOI: 10.1016/j.cemconcomp.2024.105918
Heongwon Suh , Doheon Koo , Dong-Hee Son , Jin Park , Sooheon Kim , Baek-Il Bae , Chang-Sik Choi , Hongyun So , Sungchul Bae
This study addresses the limitations of conventional methods in incorporating nanomaterials, including prolonged dispersion times and handling challenges in construction field applications, by developing graphene oxide/functionalized carbon nanotube/nanosilica (GCS) sheets. The GCS sheet, as a portable sheet form of a nanomaterial composite, achieves high nanomaterial dispersibility with only 1 min of sonication. The dispersion efficiency of the GCS sheets was evaluated using UV–vis spectroscopy, zeta potential measurements, and transmission electron microscopy, and the impact on material properties was assessed using compressive strength tests. The hydration processes were investigated using X-ray diffraction and 29Si nuclear magnetic resonance, and the nanomaterial dispersion within the cement matrix was studied using synchrotron X-ray nanoimaging. The GCS sheet facilitated more effective nanosilica dispersion on the graphene oxide plane compared to the powder form, achieving optimal dispersion in 1 min. This resulted in enhanced compressive strength, increased polymerization of calcium silicate hydrates, and a more elongated pore structure owing to the reduced aggregation of the GCS composites.
{"title":"A novel strategy utilizing graphene oxide/functionalized carbon nanotube/nanosilica sheet for nanomaterial incorporation in cement paste","authors":"Heongwon Suh , Doheon Koo , Dong-Hee Son , Jin Park , Sooheon Kim , Baek-Il Bae , Chang-Sik Choi , Hongyun So , Sungchul Bae","doi":"10.1016/j.cemconcomp.2024.105918","DOIUrl":"10.1016/j.cemconcomp.2024.105918","url":null,"abstract":"<div><div>This study addresses the limitations of conventional methods in incorporating nanomaterials, including prolonged dispersion times and handling challenges in construction field applications, by developing graphene oxide/functionalized carbon nanotube/nanosilica (GCS) sheets. The GCS sheet, as a portable sheet form of a nanomaterial composite, achieves high nanomaterial dispersibility with only 1 min of sonication. The dispersion efficiency of the GCS sheets was evaluated using UV–vis spectroscopy, zeta potential measurements, and transmission electron microscopy, and the impact on material properties was assessed using compressive strength tests. The hydration processes were investigated using X-ray diffraction and <sup>29</sup>Si nuclear magnetic resonance, and the nanomaterial dispersion within the cement matrix was studied using synchrotron X-ray nanoimaging. The GCS sheet facilitated more effective nanosilica dispersion on the graphene oxide plane compared to the powder form, achieving optimal dispersion in 1 min. This resulted in enhanced compressive strength, increased polymerization of calcium silicate hydrates, and a more elongated pore structure owing to the reduced aggregation of the GCS composites.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"157 ","pages":"Article 105918"},"PeriodicalIF":10.8,"publicationDate":"2024-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142902105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}