Advances in Civil Engineering
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2018
·
IF 0.827
Rui Ma,Liping Guo,Wei Sun,Zhidan Rong
Silica fume (SF) is a valuable nanoscaled industrial by-product used in cementitious materials owing to its filling and pozzolanic effect. However, the heavy agglomeration of SF is a severe and common problem. In this study, surface modification with polyacrylic acid (PAA) was applied on SF to achieve a better dispersion and to optimize the hydration process of cement at early age. The particle size distribution and surface properties of SF, as well as the cement hydration with modified SF, were investigated. The results demonstrated that the agglomeration of SF particles was efficiently mitigated by the surface treatment with PAA, and the acceleration effect of SF was delayed by the resistance of the surface layer at early age. However, the grafted PAA layer eventually dropped in alkali solution after 6 hours, and the hydration rate was increased again and continued for long time. This work indicated that surface-modified SF was well dispersed and was able to regulate the hydration rate of cement.
研究领域:
建筑材料学
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胶凝材料科学
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产品关联
DOI
高影响因子
Crystals
·
2022
·Vol. 12
·期 2
·144
·
IF 2.67
Shun Zhou,Xiaotao Zhang,Han Zhou,Dongxu Li
In the present research work, the ternary effects of varying dosages of graphene oxide encapsulated silica fume (GOSF), nano-silica sol (SS), and fly ash (FA) on the rheological properties, compressive strength, the content and crystal size of calcium hydroxide (CH), porosity, water absorption, and microstructure of cement were studied. The results showed that the incorporation of SF improved the dispersion of GO in the cement matrix. GOSF was prepared through electrostatic attraction between the positively charged SF and negatively charged GO. The ternary mixture of GOSF, SS, and FA had a synergistic effect that improved the performance of cement. When the curing age of cement reached 28 days, the compressive strength reached a peak of 86.5 MPa, the minimum values of content and crystal size of CH were 11.55% and 45.69 nm, respectively, and the minimum values of water absorption and porosity were 0.0011 cm/s0.5and 13.56%, respectively. In terms of microstructure, the denser structure of C-S-H gel and the regular arrangement of CH were noticed.Keywords:silica fume;silica sol;graphene oxide;fly ash;orthogonal experiment
研究领域:
土木工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
CEMENT & CONCRETE COMPOSITES
·
2024
·
IF 10.8
Aidarus Yonis,Yanchen Oinam,Prabhat Vashistha,Aron Berhanu Degefa,Geta Bekalu Belayneh,Solmoi Park,Sukhoon Pyo
This study investigates the environmental and mechanical implications of incorporating silica fume into lime-activated thermo-mechanically treated waste concrete powder (TMWCP) to develop a sustainable clinker-free binder. The novel activation method involves thermo-mechanical treatment of WCP, followed by lime and calcium formate chemical activation. The results demonstrated that incorporating silica fume enhanced the pozzolanic reactivity , which led to the formation of C–S–H, pore refinement, and a dramatic increase in compressive strength . For instance, the incorporation of 20 % and 25 % silica fume exhibited compressive strength of 46 MPa and 43 MPa after 28 days of curing. The developed clinker-free binder with the addition of 20 % silica fume demonstrated a reduction in mineral resource consumption of 99.3 % and CO 2 emissions of 13 % and 69.3 % compared to the sample without silica fume and ordinary Portland cement , respectively. This study offers a promising avenue for the widespread utilization of WCP as an environmentally friendly clinker-free binder.
研究领域:
建筑材料学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2020
·
IF 4.419
Yongshan Tan,Hongfa Yu,Shikuan Sun,Chengyou Wu,Hao Ding
Silica fume (SF) as an important supplementary cementitious material has been widely used in Portland cement, but few published articles have reported on the effect of SF on the performance and hydration mechanism of basic magnesium sulfate cement (BMSC). In the present work, the properties, microstructure and hydration mechanism of BMSC influenced by SF was studied systematically. The results show that the setting time and compressive strength of BMSC may increase with the increase of SF content, while the hydration heat will decrease with the increase of SF content. Mercury intrusion porosimetry (MIP), X-ray computed tomography (X-CT), scanning electron microscope- Energy dispersive spectrometer (SEM-EDS) results show that SF exhibits filling effect in the BMSC matrix, which makes the microstructure of BMSC matrix with SF more compact. In addition, solid-state magnetic resonance (NMR) and SEM-EDS analysis indicate that the activity of SF was excited in the BMSC matrix, resulting in the formation of M−S−H gel.
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
·
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
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资源与环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
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2019
·Vol. 140
·期 5
·2225-2235
·
IF 2.471
Wang Yansheng,Xu Zhenhai,Wang Jinbang,Zhou Zonghui,Du Peng,Cheng Xin
Synergistic effect of nano-silica and silica fume on hydration properties was studied in cement-based materials. In the present study, various tests were used to characterize hydration properties including hydration rate, non-evaporable water content, crystal phase analysis, pore size distribution, micrographs of hydration products and compressive strength. The results showed that nano-silica can significantly increase the non-evaporable water content and decrease calcium hydroxide (CH) content at 3 days, while the silica fume takes equal effect at 28 days. The addition of 0.8 mass% nano-silica and 12.5 mass% silica fume can increase the total hydration heat of cement paste by 48.49% compared with the control sample. Besides, the total porosity of hardened cement sample reduces by 6.14%, which finally results in the more compact matrix of hardened paste. In addition, the microstructure of hardened paste changes from porous to dense matrix at 3 days after nano-silica and silica fume modification. Silica fume concrete incorporated with 1.2 mass% nano-silica significantly increased the compressive strength for 3 days. Synergistic effect mechanism of nano-silica and silica fume on the filling effect enriches particle size distribution by combination of nanoscale fineness of nano-silica and micron scale fineness of silica fume. In the meantime, nano-silica can effectively remedy the insufficient activity of the silica fume in the early age.
研究领域:
土木工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Sustainable Cement-Based Materials
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2017
·
IF 0
Xiuzhi Zhang,Xiaoha Du,Xiaoyan Zhao,Rui Zhang,Pengkun Hou,Zonghui Zhou,Xin Cheng
To understand the synergistic effect of nano-SiO2(NS) and silica fume (SF) on cement-based material, the hydration process, the compressive strength development, and the pore structure of cement-based materials with the addition of nano-SiO2 and SF were investigated. The results showed that the compressive strength of cement paste increased with the increase of NS, especially at the early ages. Compared with 10% SF, the incorporation of 3% NS in the cement pastes with 7%wt dosage of SF has the highest compressive strength (51.93 MPa). When replace SF with 3% NS, the hydration of cement was promoted, C–S–H gel increased as more calcium hydroxide was consumed. Three percent NS and 7% SF can significantly reduce the porosity of the cement matrix, which is also an explanation of the phenomenon of increased compressive strength.
研究领域:
土木工程
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材料科学
✓ 已验证
DOI
Materials Advances
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2024
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IF 5.2
Yan Xu,Jian Shen,Lingling Dong,Xiaoyi Jiao,Lei Zhang,Jiaqi Yang,Shanxiang Xu,Xianyan Yang,Huiming Zhong,Guoli Yang,Zhongru Gou
Some silicate- and phosphate-based bioactive ceramics exhibit excellent biocompatibility and undergo biodegradation to different extents, thereby attracting extensive attention and showing application in the field of bone tissue engineering. Moreover, functional ion doping is a versatile strategy for optimizing the performance of bioceramics. Herein, we developed a series of core–shell bio-ceramic granules, with zinc-doped wollastonite (CSi–Zn) as the core and tricalcium phosphate (TCP) or sodium-doped tricalcium phosphate (TCP–Na) as the shell, using a coaxial dual-nozzle system. The thickness ratio of the core and shell layers was finely controlled as 2 : 1 or 1 : 1. An in vitro immersion test demonstrated that the core–shell structure and functional ion doping could tailor the ion release behavior and granule dissolution in tris buffer, and the CSi component readily induced biomimetic re-mineralization in simulated body fluids. Critical size femoral bone defect repair experiments indicated that when the core–shell thickness ratio was 1 : 1, CSi–Zn@TCP granules exhibited superior bone repair performance at 18 weeks of post-implantation. This advantage was also particularly significant in the early stages (8 weeks) of post-implantation. Altogether, the tunable composition and structure of granule biomaterials offer excellent flexibility and feasibility, with the potential for the development of a series of derivative and variant products to address various clinical requirements.
研究领域:
生物材料学
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骨组织工程
·
医学材料
✓ 已验证
产品关联
DOI
高影响因子
Journal of Cleaner Production
·
2018
·
IF 5.651
Yan Chen,Han Ding,Beifu Wang,Qian Shi,Junkai Gao,Zhixing Cui,Yechao Wan
A new shape-stable phase change material (PEG/Dop-SF) was developed by using biomimetic modification of silica fume (SF) with dopamine (Dop) as the supporting matrix (Dop-SF). Biomimetic modification with dopamine has many advantages, such as a lack of toxicity and pollution, mild conditions and easy operation, and could improve the crystallization behaviours of PEG molecules in the PEG/Dop-SF. Moreover, the DSC results shows that the phase change enthalpy of PEG/Dop-SF is higher than that of PEG/SF. When the poly-dopamine adhered to the SF , the o-dihydroxybenzene of the dopamine linked with the hydroxyl of the SF by hydrogen bonding, leading to the freeing of the imino groups of poly-dopamine; therefore, in the process of fixing PEG in Dop-SF, the free imino groups of the poly-dopamine combined with the hydroxyl of the PEG by hydrogen bonding. This mechanism is inferred to characterize the interaction between PEG and Dop-SF. According to the results of the DSC and TGA measurements, the PEG/Dop-SF exhibited favourable heat storage capacity and thermal stability properties.
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
CONSTRUCTION AND BUILDING MATERIALS
·
2021
·
IF 6.141
Xiaoling Wang,Chenchen Gong,Jianguo Lei,Jing Dai,Lingchao Lu,Xin Cheng
The main focus of this study was to investigate the effect of silica fume (SF) and nano-silica (NS) on hydration behavior and mechanism of high sulfate resistance Portland cement (HSRPC), and were analyzed in terms of chemical shrinkage, setting time, compressive strength, rheology, pore structure, hydration heat, and hydration products. Experimental results showed that 5 wt% SF deepened the secondary hydration reaction of HSRPC, because calcium hydroxide (CH) produced by HSRPC hydrating effectively stimulated the pozzolanic activity of SF at later ages. Compared with HSRPC, the 28 d total porosity and CH content of HSRPC with 5 wt% SF respectively reduced by 6.1% and 4.4%. The corresponding compressive strength increased by 14.4%. 0.1–0.3 wt% NS moved up the acceleration period of the hydration and reduced setting time. Meanwhile, NS with high pozzolanic activity evidently increased chemical shrinkage and compressive strength at early ages. Compared with HSRPC, the 28 d total porosity of HSRPC with 5 wt% SF and 0.3 wt% NS reduced by 16.3%. The CH content in TG-DTG curve was reduced by 24.7%, which was consistent with the reduction of CH characteristic peak value. Therefore, in the later hydrating process, the synergistic effect of SF and NS significantly promoted the second hydration reaction.
研究领域:
土木工程
·
材料科学
✓ 已验证
DOI
高影响因子
CEMENT & CONCRETE COMPOSITES
·
2022
·
IF 9.93
Yangyang Zhang,Jun Chang,Qingxin Zhao,Wing Lun Lam,Peiliang Shen,Yanjie Sun,Dahai Zhao,Chi Sun Poon
Seawater and sea-sand based ultra-high performance concrete (UHPC) is currently regarded as one of the most innovative and promising construction materials. To provide design guidance for the usage of silica fume (SF) during the production of seawater and sea-sand based UHPC, this work investigated the effect of SF on the later-age macro-performances and micro/nanostructure of seawater ordinary Portland cement (OPC) pastes prepared with a low water-to-binder (W/B) ratio. The results showed that the optimal SF dosage in seawater OPC-SF system was 10 wt% while that for the deionized (DI) water OPC-SF system was 20 wt%. This showed that the usage of SF could be reduced for the production of the seawater based UHPC system. It was found that the later-age compressive strength of seawater OPC-SF system was increasingly degraded with increasing SF dosage when compared with the corresponding DI water OPC-SF system. The difference in the distribution of unhydrated clinkers in the matrix as SF addition increased was the main cause. The seawater OPC-10%SF system exhibited the highest compressive strength and the lowest pore content among all the seawater-OPC systems. Additionally, with the usage of this ultra-low W/B ratio, Friedel's salt was only present in the seawater OPC pastes prepared without SF, but absent in the seawater OPC-SF pastes.
研究领域:
建筑材料
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水泥基材料
·
混凝土耐久性
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纳米结构表征
·
海洋工程材料
✓ 已验证
DOI
高影响因子
Journal of Building Engineering
·
2025
·
IF 7.4
Qingping Wang,Zhiwei Cheng,Feifei Zhou,Jingyi Cai,Liang Yuan,Xiujuan Feng,Luyao Wang,Jiayao Zhang,Xiang Li
Research on anti-dispersion grouting materials helps improve the retention and durability of grout under water-bearing or flowing-water conditions, reduce material consumption and environmental risks, and provide technical and theoretical support for the reliability and sustainability of ground reinforcement projects. This research utilized coal gangue (CG), fly ash (FA), and silica fume (SF) as raw materials rich in silicon and aluminum. Alkali activators with varying concentrations were prepared by mixing sodium silicate solution with NaOH, and a small quantity of admixture was added to develop a cost-effective anti-dispersion grouting material (AGM). The macro tests evaluating fluidity, setting time, water-to-land strength ratio under static water conditions, and retention rate under flowing water conditions of AGM were designed using the response surface method. The reaction mechanism of AGM was investigated XRD, FTIR, SEM-EDS, and NMR techniques. The results indicate that when the content of hydroxyethyl methyl cellulose (HEMC) is 0.5 %, the modulus of water glass is 1.53M, and the concentration of alkali activator is 0.45, the optimal formula can be achieved. This material exhibits excellent flowability during construction, ensuring smooth grouting operations. It also demonstrates outstanding resistance to water scouring, forming a high-strength underwater consolidation body in static water environments.
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）