Cement & concrete composites最新文献_第9页

Prediction of microbial-induced calcium carbonate precipitation for self-healing cementitious material

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-02-03 DOI: 10.1016/j.cemconcomp.2025.105945

Hsiao Wei Lee , Seyed Ali Rahmaninezhad , Li Meng , Wil V. Srubar III , Christopher M. Sales , Yaghoob (Amir) Farnam , Mija H. Hubler , Ahmad R. Najafi

{"title":"Prediction of microbial-induced calcium carbonate precipitation for self-healing cementitious material","authors":"Hsiao Wei Lee , Seyed Ali Rahmaninezhad , Li Meng , Wil V. Srubar III , Christopher M. Sales , Yaghoob (Amir) Farnam , Mija H. Hubler , Ahmad R. Najafi","doi":"10.1016/j.cemconcomp.2025.105945","DOIUrl":"10.1016/j.cemconcomp.2025.105945","url":null,"abstract":"<div><div>Microbial-induced calcium carbonate precipitation (MICCP) is a biomineralization process utilizing microbial metabolic activities to precipitate calcium carbonate (CaCO<sub>3</sub>). In recent years, there has been increasing interest in the application of MICCP in self-healing cementitious materials. In this research, the chemical and enzyme kinetics of MICCP were numerically modeled, focusing on the ureolytic bacteria responsible for the ureolysis reaction, which facilitates the precipitation of CaCO<sub>3</sub>. The model considers the growth and decay of bacteria, the ureolysis reaction catalyzed by the urease enzyme of the bacteria, the shift in bicarbonate equilibrium due to pH variation of the solution, and the calcium carbonate precipitation. In the simulation, the concentration of chemicals and bacteria as a function of time was computed. Additionally, the distribution of chemicals due to fluid transport were determined. The capability of the model was demonstrated through several benchmark simulations, including its application in self-healing concrete with a vascularized channel system. Experimental studies were also conducted to first calibrate the model parameters and then validate the model results. The predicted CaCO<sub>3</sub> precipitation defines a crack filling ratio, <span><math><msub><mrow><mi>h</mi></mrow><mrow><mi>d</mi></mrow></msub></math></span>, which is discussed in many damage-healing literature. Once the mechanical properties of MICCPs are determined, the strength recovery of self-healing concrete incorporating MICCP can then be further modeled.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"158 ","pages":"Article 105945"},"PeriodicalIF":10.8,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143077301","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}

引用次数: 0

Effects and mechanisms of the hybrid-modified SAP with calcium sulfate dihydrate on the properties of UHPC

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-01-31 DOI: 10.1016/j.cemconcomp.2025.105962

Deyu Kong , Zhentao Han , Zhiyang Chen , Chenxu Ni , Haotian Wu , Yaqian Liang , Kui He , Jintao Liu

{"title":"Effects and mechanisms of the hybrid-modified SAP with calcium sulfate dihydrate on the properties of UHPC","authors":"Deyu Kong , Zhentao Han , Zhiyang Chen , Chenxu Ni , Haotian Wu , Yaqian Liang , Kui He , Jintao Liu","doi":"10.1016/j.cemconcomp.2025.105962","DOIUrl":"10.1016/j.cemconcomp.2025.105962","url":null,"abstract":"<div><div>In the synthesis process of superabsorbent polymer (SAP), calcium sulfate dihydrate (C$H<sub>2</sub>) dispersion in water or colloidal silica sol (CSS) was used for the modification of SAP. The effects of modification on water absorption of SAP in water or saturated calcium hydroxide (CH) solution and the impacts and mechanism of the modified SAP on the performance of UHPC were investigated. The results showed that the modification results in a significant decrease in water absorption in both tap water and saturated CH solution for the SAP with water-based dispersion, but an increase in saturated CH solution though a decrease in tap water for that with the CSS-based dispersion. The SEM observation showed that a large amount of long ettringite crystals formed around the voids left by the SAP modified with the water-based dispersion. However, few ettringite crystals but more hydration products were observed to fill in the voids and a C-S-H gel shell-structure was also found in the voids left by the SAP modified with the CSS-based dispersion. Because of these, it was interestingly found that the crack resistance was further improved and a significant improvement in both flexural and compressive strength was observed, though the internal curing effect was weakened because some internal curing water carried by the SAP was consumed during the formation of the ettringite crystals and the C-S-H gels in the voids.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"157 ","pages":"Article 105962"},"PeriodicalIF":10.8,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143071710","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}

引用次数: 0

Relation between pore structure uniformity and compressive strength of iron tailings mortar

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-01-31 DOI: 10.1016/j.cemconcomp.2025.105964

Yi Li, Mengxuan Yu, Wei Li, Xin Bian

{"title":"Relation between pore structure uniformity and compressive strength of iron tailings mortar","authors":"Yi Li, Mengxuan Yu, Wei Li, Xin Bian","doi":"10.1016/j.cemconcomp.2025.105964","DOIUrl":"10.1016/j.cemconcomp.2025.105964","url":null,"abstract":"<div><div>Pore structure uniformity is one of the key factors affecting the compressive strength of mortar. This study proposed two new methods to characterize the uniformity of pore distribution and established their relationship with compressive strength. Compressive and pore structure tests were carried out on ordinary mortar, iron tailings mortar, and iron tailings mortar containing basalt fibers and polyacrylate emulsion. The first method uses the quadrat-based method calculated based on pore area and regional distribution, while the second method utilizes the average nearest neighbor index determined based on the distance between pore boundaries. Correlation analysis was used to model the relation between pore distribution uniformity and compressive strength. The results showed that iron tailings, basalt fibers and polyacrylate emulsion all reduced the compressive strength and pore distribution uniformity of mortar. The standard deviation of porosity and the average nearest neighbor index can accurately characterize the uniformity of pore distribution of mortar. Both methods show strong linear correlations with the compressive strength, in particular with the average nearest neighbor index. By introducing new methods to accurately characterize the uniformity of the pore distribution of mortar, this study provides the theoretical basis for in-depth understanding of the influence of pores on the macroscopic properties of materials.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"157 ","pages":"Article 105964"},"PeriodicalIF":10.8,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143071709","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}

引用次数: 0

Integrated assessment of magnesium phosphate cement repaired concrete from the perspective of mechanical, geometric and electrochemical compatibility

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-01-30 DOI: 10.1016/j.cemconcomp.2025.105958

Sijia Liu , Ken Yang , Long Yu , Linglin Xu , Qiang Yuan , Kai Wu , Zhenghong Yang

{"title":"Integrated assessment of magnesium phosphate cement repaired concrete from the perspective of mechanical, geometric and electrochemical compatibility","authors":"Sijia Liu , Ken Yang , Long Yu , Linglin Xu , Qiang Yuan , Kai Wu , Zhenghong Yang","doi":"10.1016/j.cemconcomp.2025.105958","DOIUrl":"10.1016/j.cemconcomp.2025.105958","url":null,"abstract":"<div><div>Magnesium phosphate cement (MPC) has gained more and more attention in the field of rapid repair and strengthening of normal concrete and reinforced concrete structures. Although the performance of MPC itself is of great concern, its compatibility with existing concrete is poorly understood. An effective testing method is necessary to assess the reliability of utilizing MPC mortar repairing construction comprehensively. In this work, systematic assessment methods regarding the mechanical, geometric and electrochemical compatibility between MPC repair mortar and concrete substrate were proposed. Five interesting repaired patterns were designed. The observed results showed that the composite system demonstrates excellent interfacial bonding and overall mechanical properties. The 3-h bond strength of the vertical repair interface repaired pattern reached 3.1 MPa, and comparable or even higher flexural strength was observed in the horizontal interface and compound interface repaired patterns. A novel MPC-NC ring was employed to monitor the interface bond stress evolution, which is a time-dependent function that develops rapidly in the early stages and is affected by relative humidity. The steel rebar in the repaired system (half repair mortar/half concrete substrate) exhibited superior corrosion protection even after 180 days of exposure in 3.5 wt% NaCl solution. The electrochemical compatibility mechanism can be contributed to the passivation process and the inhibition of charge transfer in the repaired area. This study lays a solid foundation for applying MPC repair material in practical engineering and carries out a compatibility evaluation.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"157 ","pages":"Article 105958"},"PeriodicalIF":10.8,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143071711","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}

引用次数: 0

Improving the performance of SiO2 nanoparticles in portland-limestone cementitious systems using silica-limestone composites

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-01-29 DOI: 10.1016/j.cemconcomp.2025.105961

Qitong Liu , Payam Hosseini , Bu Wang

{"title":"Improving the performance of SiO2 nanoparticles in portland-limestone cementitious systems using silica-limestone composites","authors":"Qitong Liu , Payam Hosseini , Bu Wang","doi":"10.1016/j.cemconcomp.2025.105961","DOIUrl":"10.1016/j.cemconcomp.2025.105961","url":null,"abstract":"<div><div>This study examines the effectiveness of doping SiO<sub>2</sub> nanoparticles onto limestone substrates to mitigate nanoparticle agglomeration, thereby enhancing their performance through improved dispersion within the cement paste matrix. SiO<sub>2</sub> nanoparticles were doped onto the limestone particles using the wet doping method, and the resulting SiO<sub>2</sub>-nanoparticle-limestone composite was incorporated into cement paste systems. To thoroughly examine the effects of SiO<sub>2</sub>-nanoparticle-limestone composite on the properties of cement paste mixtures, SiO<sub>2</sub> nanoparticles with two different specific surface areas (90 m<sup>2</sup>/g and 300 m<sup>2</sup>/g) and at various dosages (1.4 %, 2.8 %, and 5.6 % by weight of the total binder) were doped onto the limestone particles. Results show that doping SiO<sub>2</sub> nanoparticles onto the limestone particles reduced the required amount of superplasticizer, decreased calcium hydroxide content through intensified pozzolanic activity, refined the pore structure, and enhanced compressive strength in cement paste systems, compared to the direct addition of colloidal SiO<sub>2</sub> nanoparticles during mixing process. These findings suggest that the SiO<sub>2</sub>-nanoparticle-doped limestone composite has the potential to develop cement-based materials with substantially reduced clinker content, enhanced mechanical strength, and a refined pore structure.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"157 ","pages":"Article 105961"},"PeriodicalIF":10.8,"publicationDate":"2025-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143055592","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}

引用次数: 0

Improved microstructure and compressive strength of pastes and mortars containing MgO-SiO2 cement produced by combined calcination of MgCO3 and kaolin

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-01-28 DOI: 10.1016/j.cemconcomp.2025.105959

J.P.B. Batista , G.C. Cordeiro , L.F. Ribeiro , J.C.B. Moraes

{"title":"Improved microstructure and compressive strength of pastes and mortars containing MgO-SiO2 cement produced by combined calcination of MgCO3 and kaolin","authors":"J.P.B. Batista , G.C. Cordeiro , L.F. Ribeiro , J.C.B. Moraes","doi":"10.1016/j.cemconcomp.2025.105959","DOIUrl":"10.1016/j.cemconcomp.2025.105959","url":null,"abstract":"<div><div>MgO-SiO<sub>2</sub> cement was produced by combined calcination of MgCO<sub>3</sub> and kaolin as raw materials, at a MgCO<sub>3</sub>/kaolin mass ratio of 3.0 and 800 °C for 45 min. Separate calcination of MgCO<sub>3</sub> and kaolin was also conducted under the same conditions. Raw materials were characterized based on their chemical composition, bulk density, particle size distribution, XRD, FTIR, and BET specific surface area, and the MgO-SiO<sub>2</sub> cement produced was analyzed using XRD, FTIR, SEM/EDS, BET specific surface area, and particle size distribution. Pastes were produced to characterize microstructure and the reaction process (XRD, FTIR, TGA, isothermal calorimetry, chemical shrinkage, and SEM/EDS), and mortars to assess compressive strength. The results of BET and SEM/EDS analyses of the cements confirmed that combined calcination increased particle adhesion. Microstructural analyses of pastes after 28 days of curing at 25 °C showed the formation of a dense matrix of M-A-S-H reaction product, with aluminum incorporated into the M-A-S-H structure; brucite and hydrotalcite were also generated after the reaction process. Paste reaction results demonstrated that combined calcination produced cement with a higher degree of reaction after 72 h at 25 °C. The highest compressive strength (42.0 MPa) in mortars obtained by combined calcination was recorded after 28 days of curing at 25 °C, 223 % higher than that of separately calcined cement (13.0 MPa). As such, this study successfully applied combined calcination to produce a more strength MgO-SiO<sub>2</sub> cement.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"157 ","pages":"Article 105959"},"PeriodicalIF":10.8,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143050073","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}

引用次数: 0

Corrosion resistance of zinc in a low-carbon binder with belitic calcium sulfoaluminate cement

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-01-27 DOI: 10.1016/j.cemconcomp.2025.105956

Wenxuan Li, Jinjie Shi

{"title":"Corrosion resistance of zinc in a low-carbon binder with belitic calcium sulfoaluminate cement","authors":"Wenxuan Li, Jinjie Shi","doi":"10.1016/j.cemconcomp.2025.105956","DOIUrl":"10.1016/j.cemconcomp.2025.105956","url":null,"abstract":"<div><div>This study investigated the passivation ability and chloride-induced corrosion behavior of galvanized steel in the pore solutions of belitic calcium sulfoaluminate (BCSA) cement. Pure zinc was used to simulate the galvanized coating, and ordinary Portland cement (OPC) solution was also tested for the comparison purpose. A comparable passivation behavior was observed for pure zinc in the OPC solution and a mixture solution of 50 % OPC and 50 % BCSA cement (abbreviated as PSA solution). On the one hand, due to the high Ca<sup>2+</sup> ion concentration and low alkalinity of the PSA solution, which is conducive to zinc passivity, a more stable protective layer of calcium hydroxyzincate (CHZ) was generated on the zinc surface. On the other hand, the passivation ability of zinc was reduced to some extent by the high SO<sub>4</sub><sup>2−</sup> ion concentration in the PSA solution. During the corrosion stage induced by exogenous chlorides, a different variation tendency was found for the corrosion resistance of zinc in OPC and PSA solutions over exposure time. Owing to the synergetic attack by SO<sub>4</sub><sup>2−</sup> and Cl<sup>−</sup> ions, the critical chloride concentration of zinc in the PSA solution was only 0.3 M, as determined by a sharp drop of <em>E</em><sub>corr</sub> and <em>R</em><sub>p</sub> values, while zinc in the OPC solution exhibited a much higher chloride resistance with the critical chloride concentration of 0.8 M. However, this detrimental effect on the corrosion resistance of zinc in the PSA solution was less pronounced with prolonged exposure due to the formation of protective corrosion products.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"157 ","pages":"Article 105956"},"PeriodicalIF":10.8,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143044283","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}

引用次数: 0

An innovative structural energy storage solution using fly ash-cement composites for net-zero energy buildings

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-01-27 DOI: 10.1016/j.cemconcomp.2025.105960

Ruidan Liu , Pan Feng , Zhaolong Liu , Long Yuan , Guanghui Tao , Zhenqi Yu , Xiangyu Meng , Jian Chen

{"title":"An innovative structural energy storage solution using fly ash-cement composites for net-zero energy buildings","authors":"Ruidan Liu , Pan Feng , Zhaolong Liu , Long Yuan , Guanghui Tao , Zhenqi Yu , Xiangyu Meng , Jian Chen","doi":"10.1016/j.cemconcomp.2025.105960","DOIUrl":"10.1016/j.cemconcomp.2025.105960","url":null,"abstract":"<div><div>The rapid advancement of renewable energy highlights the urgent need for safe, cost-effective, and scalable energy storage solutions, particularly for net-zero energy buildings. In this study, we introduce an innovative energy storage solution utilizing fly ash-cement composites (FCS) as multifunctional components. The FCS, incorporating fly ash as a mineral admixture, achieves a refined pore structure and homogeneous air void distribution during early hydration, leveraging the ball-bearing characteristics and pozzolanic effect of fly ash. The optimized FCS, containing 50 wt% fly ash, exhibited an impressive ionic conductivity of 25.6 mS cm<sup>−1</sup> and a compressive strength of 5.5 MPa after just one day of curing. When integrated into structural energy storage systems, it delivers a high specific capacitance of 102.4 mAh g<sup>−1</sup> at 0.1 A g<sup>−1</sup>, an energy density of 73 Wh kg<sup>−1</sup>, and a power density of 76.3 W kg<sup>−1</sup>, maintaining 92.9 % capacitance retention over 2000 cycles. These results underscore the scalability, cost efficiency, and structural benefits of FCS, offering a promising pathway to integrate energy storage directly into buildings and infrastructure. Moreover, this strategy provides a sustainable, high-value application for large volumes of industrial solid waste while addressing energy challenges in extreme environments such as deep-sea, deep-earth, and extraterrestrial constructions.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"157 ","pages":"Article 105960"},"PeriodicalIF":10.8,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143050074","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}

引用次数: 0

Feasibility study of using carbonated and ultrasound treated electric arc furnace slag as a nano-enhanced supplementary cementitious material

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-01-27 DOI: 10.1016/j.cemconcomp.2025.105946

Jiongqi Chen , Weiyu Li , Wenjie Huang , Qiujin Chen , Yuwei Ma , Mingzhong Zhang , Zongjin Li , Jiyang Fu , Xiaowei Ouyang

{"title":"Feasibility study of using carbonated and ultrasound treated electric arc furnace slag as a nano-enhanced supplementary cementitious material","authors":"Jiongqi Chen , Weiyu Li , Wenjie Huang , Qiujin Chen , Yuwei Ma , Mingzhong Zhang , Zongjin Li , Jiyang Fu , Xiaowei Ouyang","doi":"10.1016/j.cemconcomp.2025.105946","DOIUrl":"10.1016/j.cemconcomp.2025.105946","url":null,"abstract":"<div><div>As a primary by-product of the electric arc furnace (EAF) steelmaking process, the relatively low carbonation capacity of EAF slag limits its use as a carbon-sequestering construction material. To address this limitation, this study proposed a two-step chemical-physical modification approach. First, a gas-solid carbonation process was applied, where humidity, temperature, CO₂ concentration, and carbonation duration were adjusted to specifically promote the growth of aragonite whiskers. Next, the carbonated EAF slag underwent liquid-phase ultrasound treatment, and the resulting liquid-solid mixture was used to prepare cement paste. The effect of the two-step modification was evaluated by characterizing the physical properties, microstructural evolution, and phase transformation of the EAF slag. The study further elucidated the feasibility of using modified EAF slag as a supplementary cementitious material (SCM) by examining its nucleation morphology, hydration products, and impact on hydration kinetics. Ultrasound treatment uniformly dispersed the aragonite whiskers, which acted as nanomaterials to fill the pores in the cement paste. Additionally, the exposed silica-rich surface facilitated the nucleation of C-S-H during hydration. The refined pore structure of the hardened paste ultimately resulted in a 30–50 % improvement in compressive strength compared to the untreated group and a 10–20 % increase compared to the pure ordinary Portland cement group. This study offers a novel perspective on utilizing EAF slag as an environmentally beneficial SCM, uncovering its potential properties while addressing the objectives of the CCUS strategy.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"157 ","pages":"Article 105946"},"PeriodicalIF":10.8,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143044287","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}

引用次数: 0

Influence of the water absorption-release processes of superabsorbent polymer with varying amounts of extra-entrained water on the surrounding cement paste

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-01-27 DOI: 10.1016/j.cemconcomp.2025.105953

Fangyu Chen , Jingjing Lyu , Xinchun Guan , Jing Qiao , Heqing Gou

{"title":"Influence of the water absorption-release processes of superabsorbent polymer with varying amounts of extra-entrained water on the surrounding cement paste","authors":"Fangyu Chen , Jingjing Lyu , Xinchun Guan , Jing Qiao , Heqing Gou","doi":"10.1016/j.cemconcomp.2025.105953","DOIUrl":"10.1016/j.cemconcomp.2025.105953","url":null,"abstract":"<div><div>This paper investigates the influence of the water absorption-release process of superabsorbent polymer (SAP) with varying amounts of extra-entrained water on the properties of the surrounding cement paste and the macroscopic cement paste. <sup>1</sup>H low-field nuclear magnetic resonance (NMR) was used to analyze the water absorption-release process of SAP. The macroscopic properties, including the void system, compressive strength, and autogenous shrinkage, were systematically examined. Furthermore, the degree of hydration, pore structure, and microscopic mechanical properties were investigated using large particle-size SAP (5 mm) to expand the internal curing zone. The results indicate the existence of an “equilibrium point” in the absorption-release process of SAP within cement paste. When exceeding the “equilibrium point”, the free water in the SAP is rapidly released, leading to an increase in the local water-cement ratio. This results in a looser pore structure and a reduction in the micro-mechanical properties of the internal curing zone, ultimately weakening the compressive strength. Conversely, when below the “equilibrium point”, SAP absorbs water, reducing the water-cement ratio, compacts the pore structure, and enhances the micro-mechanical properties of the internal curing zone. This improvement compensates for the reduction in compressive strength caused by voids. Additionally, when the extra-entrained water is below the “equilibrium point”, the more water entrained in SAP, the higher the gel and capillary water content, resulting in a greater reduction in autogenous shrinkage. However, when exceeding the “equilibrium point”, the content of gel and capillary water does not increase further, and autogenous shrinkage will not decrease any further.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"157 ","pages":"Article 105953"},"PeriodicalIF":10.8,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143044284","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}

引用次数: 0