CEMENT & CONCRETE COMPOSITES
·
2025
·
IF 13.1
Jihong Jiang,Yanchun Miao,Qianping Ran,Yali Li,Yunjian Li,Zongshuo Tao,Zeyu Lu
Fly ash, a by-product of coal combustion, is a pozzolanic solid waste with annual production of 1.63 billion tonnes, which has been widely used to replace cement clinker to develop sustainable concrete. However, the incorporation of high volumes of inert fly ash significantly reduces the early mechanical strength of concrete due to its low pozzolanic activity. This study presents an innovative strategy to effectively enhance the reactivity of fly ash by utilizing hydroxyl free radicals (•OH), highly reactive oxidative species generated by nano-TiO 2 under UV light excitation. Experimental results demonstrated that photoexcited nano-TiO 2 significantly promoted the depolymerization of inert glassy phases in fly ash, resulting in a 28 % increase in Ca(OH) 2 consumption within 72 h. Consequently, the compressive and flexural strengths of mortar at 28 days increased by 37 % and 16 %, respectively, with a strength activity index reaching 95.4 %. In addition, the water absorption and chloride ion diffusion coefficient were reduced by 15 % and 18 %, respectively, due to a more refined pore structure driven by enhanced pozzolanic reactivity. Density Functional Theory (DFT) calculations further revealed that •OH substantially lowered the energy barrier for Si-O-Al bonds cleavage (from 22.93 kcal/mol for OH − to 8.54 kcal/mol for •OH), confirming its superior catalytic efficiency and thermodynamic advantage. In conclusion, the findings confirm that photoexcited nano-TiO 2 can serve as an effective activator for enhancing the utilization efficiency of fly ash in sustainable concrete.
研究领域:
建筑材料学
·
可持续发展工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2024
·
IF 7.4
Chuanlin Hu,Yedongyang Liu,Xiong Qian,Yukun Qin,Yemin Dong,Fazhou Wang
The MgO production worldwide is mainly achieved through the calcination of magnesite in the wake of higher energy requirements. This study proposes an energy-saving calcination strategy through low-temperature partially calcining hydromagnesite (4MgCO 3 ·Mg(OH) 2 ·4H 2 O). Furthermore, the feasibility of using the partially calcined hydromagnesite and slag to produce a sustainable cementitious material was investigated by various techniques. This approach requires relatively low temperature and short processing time with a potential energy saving of production and CO 2 emission of fuel combustion. Moreover, it accelerates the hydration rate due to amorphous magnesium carbonate. Results indicated that the amorphous magnesium carbonate is formed during the partial calcination of hydromagnesite. It tends to transform to nesquehonite (MgCO 3 ·3H 2 O) in the initial stage of hydration, which is responsible for promoting early hydration and excellent early compressive strength. Finally, the reaction mechanism of the partially calcined hydromagnesite-based cementitious materials has been established, demonstrating its enormous potential for preparing low-carbon cementitious materials.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
CEMENT & CONCRETE COMPOSITES
·
2022
·
IF 9.93
Ruiquan Jia,Qiang Wang,Ting Luo
Understanding the workability of alkali-activated phosphorus slag (AAPS) pastes is fundamental for their efficient application. This study revealed the novel mutual inhibition mechanism through which the alkali dose and silicate modulus affect the workability of AAPS pastes based on the hydration reaction . The slump loss of NaOH-activated phosphorus slag (NAPS) paste was slow, and that of waterglass-activated phosphorus slag (WAPS) paste was faster because the soluble Si in waterglass accelerated the dissolution of the phosphorus slag (PS). At a moderate waterglass modulus, the slump losses of the WAPS pastes were slow because the moderate [Al]/{[Ca]+[Mg]} ratio in the pore solution minimized the difference in the magnitude of mutual inhibition between Ca, Mg and Al, causing all hydrates to form slowly. However, at higher and lower waterglass moduli, the WAPS pastes exhibited fast slump losses because hydrates with excess elements formed rapidly due to the excessively high or low [Al]/{[Ca]+[Mg]} ratio.
研究领域:
土木工程
·
材料科学
✓ 已验证
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2025
·
IF 8
Nan Chen,Shengtao Gao,Zijian Zong,Yingyu Wang,Dejin Xu,Chuanlei Zhu,Peiyuan Chen
This paper proposes using coal gangue powder (CGP) as an alternative to silica fume (SF) in cement-based systems, towards to high-value recycling of this coal waste. In cement-based systems, CGP offers a more affordable substitute for SF as a supplementary cementitious material. Mechanical activation enhances CGP’s reactivity by inducing structural disorder and increasing surface area, which facilitates its participation in hydration reactions. Additionally, its water retention capacity contributes to prolonged hydration and improved microstructural densification. Employing techniques such as BET analysis, rheological testing, XRD, TG-DTG, hydration kinetics, compressive strength and nanoindentation, the research compares the effects of CGP and SF on paste properties. The results indicate that SF increases plastic viscosity by 9.18 %–30.61 % and enhances compressive strength by 4.68 % at 28d, while CGP-added pastes show slight plastic viscosity to gain more distinctive rheological properties. CGP-added pastes demonstrate a comparable cumulative mass loss in TG-DTG, highlighting its positive impact on cement hydration. Additionally, CGP modifies the pore structure, increasing gel pore volume at lower dosages while maintaining a balanced distribution at higher dosages. These findings suggest that mechanically activated CGP can partially replicate SF’s effects on hydration and microstructural refinement, providing a sustainable and economical approach to enhancing cement-based materials.
研究领域:
建筑材料学
·
资源与环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF WUHAN UNIVERSITY OF TECHNOLOGY-MATERIALS SCIENCE EDITION
·
2020
·Vol. 35
·期 3
·611-619
·
IF 0.64
Zhang Feng,Bai Yin,Cai Yuebo,Chen Bo,Ning Fengwei
Triisopropanolamine (TIPA) was used as an early strength component to study its effects on mortar strength, cement paste setting time and early hydration characteristic of cement. And the early strength mechanism of TIPA at low temperature of 5 °C was also discussed. The results showed that, at 5 °C, the incorporation of TIPA promoted the condensation of cement paste, shortened the initial and final setting time, and accelerated the strength development of specimens at all ages, among which the strength after 3 d increased significantly. The 1, 3, 7, and 28 d compressive strength ratios of the mortars mixed with 1% TIPA could reach 196%, 179%, 160% and 110% respectively, and the mortar strength after 3 d exceeded that of the contrast sample cured at 20 °C. Under low temperature condition, TIPA could promote the hydration reaction of cement, shorten the induction period and advance the acceleration period. Furthermore, the maximum heat release rate and cumulative heat release quantity would be all increased, and the cumulative heat release of the cement mixed with TIPA hydrated for 12 h and 7 d increased 73% and 38% respectively. TIPA could shorten the nucleation and crystal growth (NG) stage and increase its hydration degree significantly, so it promoted cement hydration reaction. Additionally, the hydration reaction rates in phase boundary reaction (I) phase and diffusion reaction (D) phase were increased, and the duration of I process was prolonged, thereby the development of specimen strength would be accelerated. TIPA did not obviously change the types of hydration products, but increased the content of Ca(OH) 2 in the samples and the degree of cement hydration. After hydration to 7 d, large amounts of hydration products, whose surface was smooth, were formed and bonded into sheets, and the structural density of samples improved significantly.
研究领域:
建筑材料学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Shuai Li,Yaowu Wei,Bingrong Li,Xiujuan Wang,Junfeng Chen
The phase composition, microstructure, and hydration process of C 3 A with different MgO content were compared to elucidate the mechanism of hydration resistance of CaO improved by MgO–C 3 A solid solution . The process of hydration heat release was detected by isothermal calorimetry and the hydration products were analyzed by X-ray diffraction and scanning electron microscope. The results showed that the addition of MgO resulted in lattice distortion of C 3 A. In the middle and late stages of the hydration process, Mg(OH) 2 and amorphous gel-like substances covered the surface of the unreacted C 3 A and reduced the hydration reaction rate. The addition of MgO effectively reduced the hydration activity of the MgO–C 3 A solid solution that indicated the addition of MgO can improve the hydration resistance of CaO materials.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CEMENT AND CONCRETE RESEARCH
·
2022
·
IF 11.958
Gaoyin Zhang,Dan Long,Weining Xu,Xiaowei Cheng,Sheng Huang,Chunmei Zhang,Ming Zhou,Kaiyuan Mei,Liwei Zhang
High-ferrite oil-cement (HFOC) has attracted extensive research interest owing to its excellent mechanical properties and corrosion resistance . However, it is difficult to distinguish ferrite and its hydration products in cement paste . Therefore, establishing the mechanism of improvement of the mechanical properties of Portland cement upon the addition of ferrite is challenging. In this study, spherical ferrite (SF) was prepared via jet granulation to explore the mechanism of hydration and improvement of mechanical properties of oil-well cement pastes upon the addition of ferrites. XRD results showed that the crystal structure of the SF is consistent with that of ferrite. Phase analysis of the hydration products revealed that the hydration products in the AFm phase gradually covered the SF particles entirely during the early hydration reaction and transformed into cubic crystals C 3 (A, F)H 6 during the subsequent hydration reaction. The assessment of mechanical properties demonstrated that the compressive and tensile strengths of the oil-well cement paste increased by 11.7 % and 17.5 %, respectively, upon the addition of 4 % SF. Moreover, the addition of SF reduced the elastic modulus of the cement paste. The mechanical properties enhancement mechanism of SF in oil well cement involves participating in the hydration process of oil-well cement and consuming fracture energy . This study provides theoretical support for the development mechanism of mechanical properties of oil-well cement.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2021
·
IF 6.141
Zhengbin Yan,Pengwei Yang,Jiaxin Huang,Qian Jia,Jing Wen,Jinmei Dong,Weixin Zheng,Chenggong Chang,Hongning Wang,Ruoyu Chen
In this work, the Magnesium oxychloride cement (MOC) added with five kinds of inorganic salts (CaCl 2 , Ca(NO 3 ) 2 , KCl, LiCl, and NH 4 NO 3 ) were prepared under the low temperature (5 ℃), and the effects of inorganic salts on the hydration reaction and engineering properties were investigated. The results show that the addition of inorganic salt can significantly improve the hydration reaction rate, increase the content of the 5-phase, and shorten the curing time. Compared with pure MOC, the compressive strength of MOC added with CaCl 2 increased by about 128% after 7 days of curing. Moreover, the existence of inorganic salts weakened the surface shielding layer [Mg(H 2 O) 6 ] 2+ of active MgO, thereby improving the zeta potential of active MgO and promoting the diffusion rate of Mg 2+ . Overall, these results could provide valuable information for studying the hydration reaction and engineering performance of MOC at low temperatures.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Minerals Metallurgy and Materials
·
2024
·Vol. 31
·期 3
·562-573
·
IF 5.6
Wang Qianqian,Yao Zequn,Guo Lijie,Shen Xiaodong
Water-quenched copper-nickel metallurgical slag enriched with olivine minerals exhibits promising potential for the production of CO 2 -mineralized cementitious materials. In this work, copper-nickel slag-based cementitious material (CNCM) was synthesized by using different chemical activation methods to enhance its hydration reactivity and CO 2 mineralization capacity. Different water curing ages and carbonation conditions were explored related to their carbonation and mechanical properties development. Meanwhile, thermogravimetry differential scanning calorimetry and X-ray diffraction methods were applied to evaluate the CO 2 adsorption amount and carbonation products of CNCM. Microstructure development of carbonated CNCM blocks was examined by backscattered electron imaging (BSE) with energy-dispersive X-ray spectrometry. Results showed that among the studied samples, the CNCM sample that was subjected to water curing for 3 d exhibited the highest CO 2 sequestration amount of 8.51wt% at 80°C and 72 h while presenting the compressive strength of 39.07 MPa. This result indicated that 1 t of this CNCM can sequester 85.1 kg of CO 2 and exhibit high compressive strength. Although the addition of citric acid did not improve strength development, it was beneficial to increase the CO 2 diffusion and adsorption amount under the same carbonation conditions from BSE results. This work provides guidance for synthesizing CO 2 -mineralized cementitious materials using large amounts of metallurgical slags containing olivine minerals.
研究领域:
材料科学
·
环境科学
·
矿物学
✓ 已验证
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2025
·
IF 8
Na Zhang,Anxin Liu,Ling Chen,Xiangyu Xue,Hongfa Yu,Mingfang Ba
This study systematically investigated the hydration process and phase evolution of MgO-MgSO₄-H₂O (M-M-H) systems with and without chemical additive at different hydration stages using X-ray diffraction (XRD), electrochemical impedance spectroscopy (EIS), hydration heat measurement, and microstructural characterization. The results demonstrate that the formation of magnesium oxysulfate cement (MOSc) product phases is intrinsically governed by Mg²⁺ concentration in the liquid phase, which is co-regulated by both raw material molar ratios and phase regions. At low Mg²⁺ concentrations, the primary hydration products in chemical additive-free MOSc are 3Mg(OH)₂·MgSO₄·8H₂O (3–1–8 phase) and Mg(OH)₂. When Mg²⁺ concentration reaches a critical threshold, 5Mg(OH)₂·MgSO₄·7H₂O (5–1–7 phase) additionally forms in the system. Chemical additive significantly alter the hydration process by enhancing Mg²⁺ concentration and promoting MgO particle participation, ultimately shifting the dominant product phases to 5–1–7 and Mg(OH)₂. These findings provide deeper mechanistic understanding of hydration reactions in M-M-H systems and offer important guidelines for research and applications of chemically modified MOSc.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Omega
·
2022
·
IF 4.132
Gang Wang,Hua Tan,Chunjing Lu,Ao Sun
SiO2@PEGMA composites were synthesized by grafting poly(ethylene glycol) methacrylate (PEGMA) on SiO2 nanoparticles via radical polymerization. The chemical structures of the SiO2@PEGMA composites were analyzed by Fourier transform infrared, 1H NMR, and transmission electron microscopy methods. The mechanical and fresh properties, hydration products, heat of hydration, microtopography, and pore structures were studied. The shell formed by the grafted PEGMA gave the SiO2@PEGMA composite a steric hindrance effect, which enabled it to have excellent dispersion stability even in the cement pore solution. The SiO2@PEGMA composites could not only effectively facilitate hydration reaction and generate calcium silicate hydrate (C–S–H) through the seeding effect but also make the pore structure more compact by the filling effect. Compared with other control groups, SiO2@PEGMA composites could obviously enhance the compressive strength of cement samples, which was increased by 36.7% after curing for 28 days.
研究领域:
材料科学
·
土木工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2019
·
IF 4.046
Wang Baomin,Deng Shuang
Graphene nanoplatelets (GNPs) with extraordinary mechanical properties have been widely cooperated in special and high-performance composites. However, the impact of GNPs on hydration process in cement composites is still ambiguous and controversial. In this research, the GNPs was dispersed by dispersants with ultrasonication. The GNPs/cement composites were prepared and their hydration process were monitored by isothermal calorimetry (TAM Air) and 29 Si NMR analysis. In addition, the pore structure and microstructure of GNPs/cement composites were tested with Mercury intrusion porosimeter (MIP) and Scanning electron microscope (SEM). And phase analysis was discussed by analysis of XRD and TG/DTG spectrums. The experimental results suggest that GNPs may contribute to accelerate the hydration reaction and more hydration products generated because of sufficient ion exchange in earlier ages and in this basis, a more compact microstructure and better mechanical properties of GNPs cement composites achieved.
研究领域:
材料科学
·
土木工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）