| 摘要: |
为了客观评价硫酸盐侵蚀下混凝土传输-反应-损伤的全过程，基于结晶压理论、体积膨胀理论及Fick第二定律，建立了考虑孔隙率、曲折度和临界损伤程度的传输模型，并通过交替隐式差分法实现了硫酸盐传输变系数求解.结果表明：预测模型结果与试验结果基本吻合，最大误差为26.7%，可较好地预测混凝土中SO42-![]() ![]() 的扩散规律；硫酸盐质量分数和临界损伤程度对混凝土剥落具有较大的影响，相同临界损伤程度下5%硫酸钠溶液中混凝土的剥落速率比其在3%硫酸钠溶液中快51.8%；相同硫酸盐质量分数下临界损伤程度从0.80增大至0.95时，混凝土的剥落厚度减小了42.9%. |
| 关键词: 混凝土 硫酸盐 传输-反应 临界损伤程度 孔结构 数值模拟 |
| DOI：10.3969/j.issn.1007-9629.2023.10.001 |
| 分类号:TU528.01 |
| 基金项目:国家杰出青年科学基金资助项目（51925903）； 国家自然科学基金资助项目（51878155） |
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| Numerical Simulation of Sulfate Attack in Concrete |
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JIANG Jinyang1, ZHENG Haorui2, SUN Guowen2, WANG Fengjuan1, LIU Zhiyong1
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1.School of Materials Science and Engineering， Southeast University， Nanjing 211189， China;2.School of Materials Science and Engineering， Shijiazhuang Tiedao University， Shijiazhuang 050043， China
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| Abstract: |
| To objectively evaluate the whole process of transport-reaction-damage of concrete under sulfate attack， a transport model considering porosity， tortuosity and critical damage degree was established based on the theory of crystallization pressure， volume expansion theory and Fick’s second law. The variable coefficient of sulfate transport was solved by alternating implicit difference method. The results show that the prediction model results are basically consistent with the experimental results， with the maximum error of 26.7%， it can effectively predict the diffusion law of sulfate ions in concrete. Analysis of influencing factors shows that the concentration of sulfate attack and the critical damage degree have a significant impact on the spalling thickness of concrete cover. Under the same critical damage degree， the spalling speed in 5% sodium sulfate solution is 51.8% higher than that in 3% sodium sulfate solution. At the same concentration of sodium sulfate solution， the critical damage degree increases from 0.80 to 0.95， and the spalling thickness decreases by 42.9%. |
| Key words: concrete sulfate transport-reaction critical damage degree pore structure numerical simulation |
