Relationship between the protective effect for chloride ion permeation and microstructure of polymer cement waterproofing membrane

在高W/B的聚合物水泥防水卷材中，可观察到横截面方向的材料分离现象。这种试件表现出类似于脆性破坏的行为，拉应力增加，伸长率显著降低。基层混凝土防水膜的应用大大减少了氯离子的渗透。然而，防水薄膜并不能完全阻止氯离子渗透到基材中。防水膜被拉长穿过基材裂纹，这种拉长降低了屏蔽性能，允许氯离子渗透到裂纹空间。EPMA观察和模拟结果表明，固化过程中材料分离。聚合物水泥防水卷材中水泥硬化段和聚合物段的分布对其力学性能和屏蔽性能有很大影响。

Material separation in the cross sectional direction was observed in polymer cement waterproofing membranes fabricated with high W/B,. Such pieces showed a behavior similar to brittle failure, with enhanced tensile stress and a significantly reduced rate of elongation.The application of a waterproofing membrane for substrate concrete drastically reduced the Chloride ion penetration. However, a waterproofing membrane does not completely prevent the penetration of Chloride ion into the substrate. The waterproofing membranes are elongated across the substrate cracking and this elongation deteriorates the shielding performance, permitting permeation of Chloride ion into the crack space.The EPMA observations and simulation results show the material separation during the curing process. The mechanical properties and shielding performance are strongly affected by the distribution of cement hardened body sections and polymer sections that comprise the polymer cement waterproofing membranes.