摘要
Recycled aggregate concrete(RAC) specimens with different recycled coarse aggregate replacement ratios by mass(R) are fully immersed in a 10% chloride solution for 235 days. Both free chloride concentration(Cf) and total chloride concentration(Ct) are then measured employing a rapid chloride test(RCT) system. The Fick's second diffusion law is verified by the test data and used to predict chloride concentration distribution at different immersion periods. Additionally, pore structures of the new and old mortar in RAC are tested by mercury intrusion porosimetry(MIP). It is found that binding chloride concentration(Cb) linearly increases with Cf. In natural aggregate concrete(NAC), Cf is obviously smaller than that in the RAC in the same testing environment and this is different from the test results of Ct and Cb. Furthermore, the effects of R on the chloride concentration of RAC become severe for specimens subjected to long immersion periods, which can be explained in terms of the pore structures of the new mortar and old adhesive mortar in RAC.
Recycled aggregate concrete (RAC) specimens with different recycled zoarse aggregate replacement ratios by mass (R) are fully immersed in a 10% chloride solution for 235 days. Both free chloride concentration (CI) and total chloride concentration (Ct) are then measured employing a rapid chloride test (RCT) system. The Fick's second diffusion law is verified by the test data and used to predict chloride concentration distribution at different immersion periods. Addilionally, pore structures of the new and old mortar in RAC are tested by mercury intrusion porosimetrV (MIP). It is found that bind- ing chloride concentration (Cb) linearly increases with Cf. In natural aggregate concrete (NAC), Cf is obviously smaller than that in the RAC in the same testing environment and this is different from the test results of Ct and Cb. Furthermore, the effects of R on the chloride concentration of RAC become severe for specimens subjected to long immersion periods, which can be explained in terms of the pore structures of the new mortar and old adhesive mortar in RAC.
基金
supported by the National Natural Science Foundation of China(Grant Nos.51325802,51250110074)
关键词
再生骨料混凝土
测试环境
氯离子扩散
氯化物溶液
氯离子浓度
循环
测重
RAC
recycled aggregate concrete (RAC), chloride diffusion, rapid chloride test (RCT), pore structure, Fick's second diffu-sion law, chloride binding