冻融损伤对表面防水混凝土渗透性影响研究

Study of Influence of Freezing-thawing Damage on Permeability Behavior of Surface Water-proofing Concrete

对表面防水混凝土和普通混凝土试件进行加速冻融循环试验,在不同循环次数下测定试件的水和氯离子渗透性,旨在研究冻融损伤对表面防水混凝土渗透性影响,为实际工程中表面防水混凝土的结构和耐久性设计提供理论依据。试验结果表明:表面防水混凝土的水和氯离子渗透量均随着冻融循环次数的增加而增加,但是,对比普通混凝土试件,在相同的冻融循环次数下,表面防水混凝土仍具有较好的抗渗透性能,可以有效降低水和氯离子的侵入量;当冻融循环次数为100次时,水灰比为0.4的普通混凝土试件最大毛细吸水量和氯离子含量分别是表面防水混凝土试件的10.18倍和1.89倍。

The accelerated freezing-thawing cycle tests with different cycling times are carried out for surface waterproofing concrete and common concrete,so as to learn the influence of freezing-thawing damage on permeability behavior of surface water-proofing concrete. The test results show that： 1） The penetrations of water and chloridion of surface water-proofing concrete increase with the freezing-thawing cycle time increases. 2） The permeability behavior of surface water-proofing concrete is superior to that of common concrete in same freezing-thawing cycle time. 3） The maximum capillary suction volume and the chloridion content of common concrete with water-concrete ratio of 0. 4 and under 100 times of freezing-thawing cycles are 10. 18 times and 1. 89 times that of surface water-proofing concrete respectively.