摘要
考虑粗骨料分布的随机性及氯离子结合的非线性对氯离子扩散性的影响,对再生混凝土中氯离子扩散进行数值建模与细观仿真分析,并将数值模拟结果与已有试验数据进行对比;通过改变老硬化砂浆扩散系数、新硬化砂浆扩散系数、老界面过渡区扩散系数及浸泡时间,对比研究了不同情况下再生混凝土中氯离子的扩散特性.结果表明:数值模拟结果与试验结果接近;再生混凝土中氯离子沿扩散深度方向呈波浪式下降;随着扩散系数的增大及浸泡时间的增长,氯离子扩散速度加快;随着再生粗骨料取代率的增加,氯离子扩散速度也增加;相同扩散深度处,不同随机骨料模型中氯离子含量最大值接近,说明所采用的随机骨料模型模拟结果具有较好的稳定性.
Concerning the effects of the random distribution of coarse aggregate and the non-linear characteristic of chloride binding on chloride diffusion,the modeling and microscopic simulation analysis for the chloride diffusion characteristics of recycled aggregate concrete （RAC ）are carried out.The simulation results are compared with the test results.Then,the chloride diffusion character-istics with different diffusion coefficients of old mortar,new mortar and old interfacial transition zone （ITZ）and different immersion times are studied.The results indicate that the simulation results and the test results are similar.The distribution of chloride diffusion in RAC declines wavily along the diffusion depth.The chloride diffusion speed accelerates with the increase of the diffusion coeffi-cients and the immersion time.Besides,with the increase of the replacement percentage of recycled coarse aggregate （RCA ）,the chloride diffusion speed of RAC increases.At the same diffusion depth,the maximum chloride concentrations in different random RAC models are similar,indicating that the simulation results of the proposed random RAC model has a good stability.
出处
《东南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2014年第6期1240-1245,共6页
Journal of Southeast University：Natural Science Edition
基金
国家自然科学基金资助项目(51325802)
关键词
再生混凝土
再生粗骨料
随机分布
氯离子扩散
细观数值模拟
recycled aggregate concrete （RAC）
recycled coarse aggregate （RCA）
random distri-bution
chloride diffusion
mesoscopic numerical simulation
