CONSTRUCTION AND BUILDING MATERIALS
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2025
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IF 8
Xiaoping Wang,Rongling Zhang,Weichen Xu,Yanshuai Wang,Xinmin Ma,Jianjun Feng
To address the deterioration of concrete structures caused by severe sulfate corrosion in western regions, which leads to reduced durability and safety, a self-sensing and self-healing anti-corrosion microcapsule with sulfate ion responsiveness was designed using polyacrylamide (PAM) as the core material and ionic liquids (ILs) as the shell material. The optimal stirring temperature and duration for microcapsule preparation were determined based on measurements of particle size distribution, ion-responsive behavior, and encapsulation efficiency. The microcapsules were incorporated into concrete at dosages of 1 %, 2 %, and 3 % of the cementitious material, and their effects on dynamic elastic modulus, pore structure, and sulfate ion concentration were examined. The mechanism was elucidated, and the sulfate corrosion rate of concrete after 480 days of indoor exposure was evaluated. The results indicate that when the stirring temperature is maintained at 70 °C and the stirring duration is 24 h, the microcapsules exhibit a uniform particle size distribution and the highest encapsulation efficiency. However, the temperature has minimal influence on the ion-responsive rate. The incorporation of microcapsules reduced the early-stage dynamic elastic modulus of concrete but significantly improved it at later stages compared to the control group. Based on the variation in relative dynamic elastic modulus, the sulfate corrosion process of concrete was divided into a performance enhancement phase, a degradation phase, and a deterioration phase, with the degradation and deterioration phases significantly delayed by the incorporation of self-sensing and self-healing microcapsules. The addition of microcapsules significantly reduced the proportion of harmful and more harmful pores, decreased the sulfate ion penetration depth, and enhanced the corrosion resistance of concrete. The findings provide a novel solution for enhancing sulfate corrosion resistance in concrete exposed to saline soil environments in western regions.
研究领域:
材料科学
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土木工程
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化学工程
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DOI
高影响因子
GEOMICROBIOLOGY JOURNAL
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2025
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IF 1.9
Chunxiang Qian,Xian Hu,Yaya Yuan,Junjie Zhang,Yijin Fan
Microbial induction of carbonate precipitation is common in nature, carbonic anhydrase (CA) secreted by microorganisms plays an important role in catalyzing the precipitation of CaCO3 from CO2. This study investigated how pH and temperature regulate microbial CA production, activity, and structure, and further examined their effects on CaCO3 deposition, steel slag carbon sequestration, and concrete crack healing. The results demonstrated that bacteria efficiently produced CA and maintained its activity over a broad range of alkaline pH levels and temperatures, the optimal conditions pH 9 and 30°C facilitated both bacterial CA production and activity by regulating growth and metabolism. Furthermore, pH and temperature modulated CA activity by altering its secondary structure (α-helices, β-turns) and weakening the enzyme’s active center for CO2 at higher pH, which consequently influenced CaCO3 deposition efficiency. The microbial treatment significantly enhanced carbon fixation in steel slag, with an 18.9% carbon sequestration rate at 48 hours, an 8% increase over the control group. In concrete crack-healing tests, the application of alkali-resistant microorganisms restored water permeability resistance to 93.24% of the original concrete after 28 d of healing. Microbial mineralization technology has great potential in steel slag carbon sequestration and self-healing concrete.
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DOI
高影响因子
Journal of Building Engineering
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2024
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IF 6.7
Yanjie Tang,Yue Li,Xiang Liu,Wanyu Chen,Katrin Schollbach,Wei Chen
The corrosion of embedded rebar in self-healing concrete is seldom reported on and deserves more intensive attention. This study focuses on utilizing biomimetic-induced hydroxyapatite as a means of achieving autonomous self-healing to target issues associated with rebar corrosion in concrete structures. A comprehensive evaluation of the synthesized supramolecular hydrogel as self-healing agent carrier, the simulated self-healing products, and the reinforcement corrosion behaviour in the upscaled self-healing concrete beams was conducted. Results show that the synthesized 2,6-bis [N-(carboxyethyl carbonyl)amino] pyridine (DAP) hydrogel qualifies as a healing agent carrier with high loading capacity and intelligent response after cracking. The feasibility of hydroxyapatite formation via a combination of phosphate ions released by the supramolecular hydrogel and the available calcium ions leached by the cement matrix has been substantiated. The addition of phosphate as the healing agent is effective in mitigating the corrosion of rebar in the designed self-healing concrete beam. It can be explained by the synergistic effect of surface adsorption of chloride ions by the formed hydroxyapatite and the corrosion inhibitor role of the released phosphate.
研究领域:
土木工程
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材料科学
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生物学
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DOI
高影响因子
Journal of Building Engineering
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2025
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IF 7.4
Zhenxing Du,Chenglong Li,Penggang Wang,Zuquan Jin,Li Tian,Aoshen Wang,Min Zhang
To overcome limitations of single-trigger self-healing systems, this study developed microcapsules (MCs) responsive to both mechanical stress and chloride ions for marine concrete repair. Ethyl cellulose/nano-silica shells encapsulating epoxy resin were synthesized via solvent evaporation method, with PbSO 4 embedded for chloride activation. MCs exhibited optimal size (70–120 μm), thermal stability (>190 °C), and homogeneous PbSO 4 distribution. Increasing PbSO 4 content enhanced chloride responsiveness, forming pores that released healing agent via osmotic pressure, while improving MC stiffness. Additionally, the self-healing mortars demonstrate notable strength recovery, with the highest healing rate of 126.30 % under standard curing and 114.50 % under seawater curing, reflecting the MCs' robust performance in aggressive environments. Cracks up to 229.7 μm width were effectively healed within 7 days, with healing efficiency positively correlating with PbSO 4 content. The porosity reduction rate rose with the increase in PbSO4 dosage, reducing porosity by 9.42 %–26.71 % post-healing. Additionally, MC significantly enhanced the chloride ion permeability resistance of self-healing mortars, achieving a reduction rate of 67.37 %–84.90 %. This d ual-trigger system provides targeted, efficient self-healing for marine concrete infrastructure, significantly enhancing durability.
研究领域:
材料科学
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土木工程
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建筑材料
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腐蚀防护
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智能材料
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结构耐久性
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）