硫酸盐环境下再生骨料混凝土的抗冻性能

Frost Resistance Property of Recycled Aggregate Concrete under Sulfate Environment

为了探讨再生骨料混凝土在硫酸盐作用下的抗冻耐久性能,选取再生粗骨料替代率为50%、100%的两组再生混凝土和普通骨料混凝土进行硫酸盐环境中的冻融试验,以质量损失率和相对动弹性模量判别混凝土的抗冻性能。结果表明:质量损失率用于表征再生骨料混凝土的损伤劣化规律具有一定的局限性;相对动弹性模量的变化比较敏感,可以很好的表征再生骨料混凝土的损伤程度;再生骨料混凝土的抗盐冻性能明显低于普通骨料混凝土。以此为基础,建立了Weibull概率函数与冻融损伤度之间的演化方程,演化方程可以很好表述冻融循环次数与相对动弹性模量的变化规律,为后续的分析研究提供了一定借鉴。

To explore frost resistance of recycled aggregate concrete with the help of sulfate,the experiment of freeze-thaw based on recycled aggregate concrete of which was 50 and 100 percent of replacement rates with two groups of recycled aggregate concrete and natural aggregate concrete in condition of sulfate was conducted to investigate the frost resistance property as the criterions were mass lose rates and relative dynamic modulus.The results showed the limited damage degree was characterized via mass lose rate and the change of relative dynamic modulus was sensitive,which can represent the damage degree of recycled aggregate concrete.The frost resistance of recycled aggregate is lower than natural concrete apparently,which can lay a basis for building the evolution equation which can illustrate the variation laws of frequency of freeze-thaw and relative dynamic modulus between Weibull probability function and freeze-thaw.It can provide some references for further studies.