Article
Construction & Building Technology
Jinpeng Dai, Qicai Wang, Xuyu Lou, Xueying Bao, Bo Zhang, Jianqiang Wang, Xin Zhang
Summary: This study investigated the effects of water-cement ratio and low temperature on the hydration heat of cement. The results showed that the cumulative hydration heat and heat evolution rate were influenced by the water-cement ratio and curing temperature, impacting the overall hydration process.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Chemistry, Physical
Jun Zhang, Guoju Ke, Yuzhang Liu
Summary: Compared to OPC, CSA displays very early-age strength and faster heat-releasing rate during hydration, with three exothermic peaks identified during the process. The addition of SF affects the timing of reaction peaks, while decreasing w/c significantly reduces heat release peaks. An optimal use of SCMs in CSA pastes under different w/c can greatly decrease heat releasing while maintaining the required strength.
Article
Construction & Building Technology
Fangmei Huang, Zhangli Hu, Shusen Li, Jianzhong Liu, Fangyu Han, Jiaping Liu
Summary: In this study, the mechanical properties, deformation, and mass change of cement pastes with a water-to-cement ratio of 0.17 under different curing conditions were compared. It was found that the compressive strength of the cement pastes initially increased and then decreased. Water consumption-induced non-uniform shrinkage played a dominant role in the evolution of the mechanical properties under self-desiccating and drying conditions. Hydration affected by water adsorption/desorption had a stronger influence on compressive strength development compared to the weakening effect induced by water adsorption/desorption itself. The contribution of the swelling of the calcium-silicate-hydrates gel on the expansion of cement paste in saturated conditions was also confirmed.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Environmental Sciences
Hamideh Mehdizadeh, Xiaoxiao Jia, Kim Hung Mo, Tung-Chai Ling
Summary: This study investigated the influence of water-to-cement ratio on the microstructure and microhardness properties of cement paste, as well as its impact on the carbonation reaction. The experimental results demonstrated that higher water-to-cement ratio led to greater hydration, affecting carbonation efficiency and depth.
ENVIRONMENTAL POLLUTION
(2021)
Article
Construction & Building Technology
Enlai Dong, Gang Li, Ziao Chen, Yuan Feng, Zhiyu Wang, Dingqiang Fan, Kangning Liu, Tianyi Yin, Rui Yu
Summary: This study investigates the hydration characteristics of ternary cementitious materials of portland cement-sulfoaluminate cement-gypsum (TCM) under restricted water content based on magnetism-heat theory. Various techniques were used to analyze the properties and reaction process of TCM, and the results showed that TCM prepared in this study exhibited high compressive strength and the duration of different hydration stages could be effectively quantified using the magnetism-heat theory.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Thermodynamics
Fanghui Han, Shaomin Song, Juanhong Liu, Ruidong Wu
Summary: The study found that partial substitution of iron tailing powder with slag can improve the properties of ternary blended cement, especially at low water/binder ratio. High temperature has a significant impact on the exothermic rate and cumulative heat of hydration. Excessive addition of iron tailing powder negatively affects the development of cement properties.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2021)
Article
Construction & Building Technology
Zhaoxia Yan, Haibo Zhang, Yu Zhu
Summary: This paper investigates the hydration process and kinetics of sulfoaluminate cement, and finds that the water/cement ratio (W/C) affects the hydration exothermic characteristics, microstructure, and strength of the cement.
MAGAZINE OF CONCRETE RESEARCH
(2022)
Article
Construction & Building Technology
Junxia Liu, Yimeng Yan, Zhongyu Li, Fei Yang, Ran Hai, Mengtian Yuan
Summary: Potassium magnesium phosphate cement (MKPC) was modified with red mud pretreated with potassium dihydrogen phosphate (KH2PO4) to enhance its water resistance, volume stability, and economy. The effects of pretreated red mud on the properties of MKPC such as fluidity, setting time, mechanical properties, water resistance, and hydration heat were investigated. The results showed that the water resistance of MKPC was significantly improved with the increase of pretreated red mud content, while the peak temperature and hydration heat were reduced. The involvement of pretreated red mud refined the crystal structure of MgKPO4·6H2O and reduced the concentration of dead burned magnesium oxide (MgO) and KH2PO4 in MKPC mixture.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Yujiao Li, Meinan Wang, Gongbing Yue, Yuanxin Guo, Zixi Xie, Qiuyi Li, Mingxu Chen, Liang Wang
Summary: This study investigated the effects of three alkaline electrolysed water, potassium-based electrolysed water (KEW), sodium-based electrolysed water (NEW), and electrolytic tap water (ETW), on the early-strength and hydration behavior of cement composites. The results showed that all three alkaline electrolysed water could improve the workability and strength of cement composites to some extent. The 28-day compressive strength of KEW, NEW, and ETW mortar increased by 7.1%, 7.7%, and 2.1%, respectively, compared to ordinary tap water mortar. The hydration process of KEW and NEW pastes was accelerated, resulting in more hydration heat and products, and a more compact paste microstructure. In contrast, the effect of ETW on the hydration behavior of paste was not noticeable, possibly due to its low OH- concentration and ionic activity, as well as the lack of positively charged metal ions.
Article
Construction & Building Technology
Xiaojuan Shu, Yuxiang Jiang, Yang Zhao, Zhenghui Xu, Mingyan Shen, Xingu Zhong
Summary: This paper proposes a new exothermic hydration model of cement-based materials, which takes into consideration the different reaction rates of multi-component active substances. The model is fit based on the experimental data and the Arrhenius chemical expression. The results show that the proposed model is more accurate than the monomial exponential function model, especially before the initial setting time.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Haitao Zhao, Yu Xiang, Wen Xu, Xiaodong Chen, Yue Zhu, Haotian Wu, Shibin Liu
Summary: The transverse relaxation time (T-2) signals of physically bound water in cement paste were monitored using low-field nuclear magnetic resonance (LF-NMR) to indicate water content change and characterize the early-age hydration process. The hydration process was divided into four typical periods using the null points of the second derivative curve obtained from the T-2 signals and hydration time, and the influences of water-cement ratio (w/c) and hydration heat regulating materials (HHRM) on the hydration process were analyzed. The experimental results showed that the hydration rate of pure cement paste in the accelerated period was positively correlated with w/c. The addition of HHRM extended all four periods and resulted in a faster initial period and a slower accelerated period of hydration rate. Lastly, an early-age hydration model of cementitious materials was proposed considering w/c and HHRM content based on the LF-NMR test results.
JOURNAL OF WUHAN UNIVERSITY OF TECHNOLOGY-MATERIALS SCIENCE EDITION
(2023)
Article
Construction & Building Technology
Zhishan Xu, Yongsheng Ji, Zhanguo Ma, Shengnan Xu, Jie Zhang, Zhongzhe Zhang, Qi Xue
Summary: This paper investigates the effects of ultrasonic action on cement-based materials and proposes that ultrasonic dispersion can effectively disperse cement particles, enhance mechanical properties, reduce the viscosity of the paste, and accelerate hydration rate.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Jiaoyang Lv, Bo Tian, Lihui Li, Lei Quan
Summary: In this study, we evaluated the effects of hydration heat inhibitors on the early hydration heat release process of cement and its main mineral components. The results showed that hydration heat inhibitors can reduce the heat release rate of cementitious materials and have a substantial effect on tricalcium silicate clinker.
FRONTIERS IN MATERIALS
(2022)
Article
Construction & Building Technology
Zhenhai Xu, Zhaoheng Guo, Yasong Zhao, Shujun Li, Xu Luo, Gaofeng Chen, Cheng Liu, Jianming Gao
Summary: This study investigates the hydration of blended cement with high-volume slag and nano-silica. The results show that nano-silica can enhance the hydration of slag and cement before 3 days, but inhibits the hydration after 3 days. Additionally, nano-silica improves the pore structure and compressive strength of hardened paste.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Construction & Building Technology
Seon Yeol Lee, Van Thong Nguyen, Sang-Yeop Chung, Jae-Heum Moon, Dong Joo Kim
Summary: A cement hydration model based on multiphase voxels and a novel dissolution rate was proposed to simulate the hydration of CNT-reinforced cement paste. The model was validated by considering accelerated or delayed hydration due to CNTs and superplasticizers. It can simulate the formation of low-density and high-density CSHs using multiphase voxels and was validated using previous experimental data.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Construction & Building Technology
Qi Jiang, Wei Liu, Shaopeng Wu, Xuanwen Gou
Summary: This study analyzes the erosion mechanisms of NaCl solution on asphalt concrete and finds that NaCl solution softens asphalt and promotes the intrusion of crystalline salt into it. Salt crystallization alters the surface roughness of aggregates, resulting in a decrease in skid resistance but an improvement in compressive strength. Additionally, the concentration of NaCl solution initially has no significant impact on the mechanical performance of asphalt concrete, but its domination gradually increases with the intensification of cyclic effects.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Lili Kan, Lan-qing Dai, Ning Kong, Bin Peng, Fei Wang
Summary: This paper investigates the effect of freezing and thawing cycles on the tensile behavior of cracked ultra-high performance concrete (UHPC). The results show that long-term freezing and thawing action deteriorates the cracking strength, tensile strength, tensile strain, and strain energy of cracked UHPC. On the other hand, the action of water generally favors the development of tensile properties of UHPC. The crack distribution tends to be unsaturated under freezing and thawing environment, and the re-hydration reaction is hindered. The pore structure near the crack varies under different environments.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Xin Xiao, Jingwei Li, Qingke Meng, Xiangshan Hou, Yanhui Liu, Xujiang Wang, Wenlong Wang, Shengtao Lu, Yuzhong Li, Yanpeng Mao, Tong Li
Summary: Preparing gypsum-based self-leveling mortar (GSLM) using beta-hemihydrate gypsum and solid wastes-derived sulfoaluminate cement (WSAC) can improve the mechanical performance of the mortar, but phosphorus impurities can weaken the hydration speed and degree.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Sihang Bao, Junzhen Di, Yanrong Dong, Ziqing Gao, Qing Gu, Yuanfang Zhao, Hongyu Zhai
Summary: Tailings dam break and leakage accidents pose a threat to the safety of people in mining areas and cause severe environmental pollution. This study focuses on solidifying tailing sand using microbial induced calcite precipitation (MICP) to improve strength and fix heavy metals. The curing time of MICP bio-cemented tailings is found to significantly impact the strength of tailings, while its effect on heavy metal fixation is minimal. The optimized MICP curing time is 10 days, resulting in improved strength and cementation of tailings particles.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Ferhat Benmahiddine, Fares Bennai, Achraf Charaka, Ameur El Amine Hamami, Abdelkader Tahakourt, Rafik Belarbi
Summary: This paper studied the effects of hysteresis on the hygrothermal behavior at the building scale. Through laboratory validation and numerical simulations, it was found that hysteresis has a significant impact on the relative humidity and total heat fluxes in buildings, while it does not have a noticeable effect on temperature variations.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
You Gao, Wei He, Xiayang Zhang, De'an Sun, Pei Li
Summary: This study determined the boundary line between the swelling and compression deformation zone in lateritic clay through wetting tests, and proposed a simple bimodal SWRC model. It also found that the existing strength model underestimated the tested values in the medium to high suction range, therefore a segmented strength equation was introduced for enhanced predictions of the strength properties of lateritic clay.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Prabhath Ranjan Kumar Soda, Asheer Mogal, Kalyan Chakravarthy, Nikhil Thota, Nimish Bandaru, Sanjay Kumar Shukla, K. M. Mini
Summary: This study investigates the use of encapsulated bacteria to improve the self-healing ability of concrete. Through various tests, it is found that using 20% cement-coated alginate beads (CCAB) and 5% nanosilica (NS) can achieve optimal strength and healing. This research is significant for enhancing the durability of concrete.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Shizhe Wang, Haiping Wu, Wen Yang, Wei Wang, Zhibo Zhu, Kun Nie, Luoxin Wang, Hua Wang, Jing Wu
Summary: In this study, photothermal-heat storage concrete (PHSC) was developed with excellent photothermal conversion performance and heat storage capacity. By absorbing and storing solar energy during the day and releasing it at night, PHSC can effectively reduce energy consumption in buildings.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Robin Deb, Jialuo He, Geetika Mishra, Yaghoob (Amir) Farnam
Summary: Incorporation techniques of phase change materials in cementitious composites have a significant influence on thermal properties. This study investigated the thermal behavior of low-temperature PCM when subjected to varying temperature change rates and pore confinement inside the porous network of lightweight aggregates. The results showed that ramp rates affect the nucleation and crystallization growth process during the phase transition, and the pore structure of the aggregates affects the supercooling phenomenon and confinement pressure of the PCM.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Eduardo Ferreira, Payam Sotoudeh, Dagmar Svecova
Summary: This study investigates the fatigue behavior of concrete under different stress reversal conditions. The results indicate that stress reversal generally causes more severe damage and reduces the cycles to failure compared to tensile fatigue. Additionally, adding some level of compression contributes to the energy required for failure under stress reversal fatigue. Specimens with higher concentration of fractured aggregates achieve longer fatigue lives.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Mag Raj Gehlot, Sandeep Shrivastava
Summary: This study evaluates the compatibility relationship between plaster bonds and the substrate under an accelerated aging environment, and finds that incorporating an appropriate amount of granite cutting waste can improve the strength parameters and adhesion of the cement mortar.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Min Zhang, Qirui Luo, Mingke Deng, Shixing Zhao
Summary: This study investigated the bond behavior between carbon FRCM composites with added short fibers and concrete substrates. The effects of different factors were considered and 36 specimens were tested and discussed. The experimental results were analyzed in terms of failure mode, load-slip curve, and characteristic parameters, and the contribution of weft yarns was taken into account in the developed bondslip model.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Dengkai Liu, Hongniao Chen, Ray Kai Leung Su
Summary: The susceptibility of building stones to fire and high temperature was investigated in this study by examining their physical and mechanical properties. The results show that both compressive and tensile properties of stones are affected by temperature changes. The tensile strength is particularly sensitive to temperature changes, requiring special attention to the components subjected to tensile stress in stone buildings. Principal component analysis was used to predict the mechanical properties of stones, providing a new method for calculating the residual mechanical properties after high temperature or fire.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Joso Maria Raposo, Eduardo Cavaco, Luis Costa Neves, Eduardo Julio
Summary: This paper investigates the correlation between the friction coefficient and the surface roughness of concrete-to-concrete interfaces. Experimental tests were performed on specimens with different surface treatments, and the surface roughness parameters were analyzed and correlated with the shear strength and friction coefficient. The results showed that certain roughness parameters had a strong positive correlation with the friction coefficient, while others had little or no correlation. A novel combined roughness parameter with optimized correlation was proposed.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Chiara Riccardi, Massimo Losa
Summary: The interest in using bio materials in asphalt pavements is growing due to economic reasons and environmental benefits. This study aimed to review the use of bio extenders as additives in binders, with a focus on replacements greater than 20% of fossil binder. The properties of bio-extended binders were found to vary substantially depending on the biomass source and production process.
CONSTRUCTION AND BUILDING MATERIALS
(2024)