静力弯曲荷载作用下地下结构混凝土硫酸盐侵蚀试验研究

摘要

硫酸盐侵蚀是导致地下结构混凝土材料性能劣化的主要原因之一。进行了静力弯曲荷载与硫酸盐浸泡耦合腐蚀试验，测定并研究了混凝土残余抗弯强度退化规律和相对动弹性模量的发展规律；利用化学滴定方法（ EDTA）测得了混凝土中硫酸根离子的浓度分布规律。试验结果表明，长期静力荷载及硫酸盐侵蚀的共同作用加速了混凝土材料中硫酸根离子的扩散和材料性能的劣化。%Sulfate attack is one of the main causes leading to mechanical deterioration of underground concrete materials. The corrosive experiment of specimens subjected to static bending load and sulfate was undertaken. The deterioration of residual flexural strength of concrete and relative dynamic modulus of elasticity were measured and studied. The chemical titration method( EDTA)was utilized to measure the distribution of sulfate ion concentration in concrete. The test results show that the coupled action of long-term static ben-ding load and sulfate attack accelerated the diffusion of sulfate ions in to concrete and deterioration of material properties of concrete.