土壤环境中电场与硫酸盐对水泥基材料性能的影响及机理

Effect of Electrical Field and Sulfate on Cement-based Materials under Soil Environment and Its Mechanism

在土壤环境中,脉冲电场与硫酸盐共同作用来模拟城市轨道交通环境,研究该环境对水泥基材料性能的影响。通过外观破坏、抗压强度、离子分布、扫描电子显微镜(SEM/EDS)及X射线衍射(XRD)等方法表征。研究表明:在土壤环境中,电场会加速SO2-4的迁移。电场条件下的SO2-4迁移量约为未施加电场的2~4倍;同时,电场条件下水泥基材料的抗压强度下降幅度约为未施加电场的4~10倍。表明城市轨道交通环境中的水泥基材料遭受比普通环境更为严重的硫酸盐侵蚀,应采取一定的措施预防和减缓。

Sulfate and electrical pulse acted together under soil environment to simulate the urban railway system and study the effect on cement-based materials. The changes were analyzed by appearance corrosion,corrosion resistant coefficient,distribution of sulfate ions,scanning electron microscope（ SEM/EDS） and X-ray diffraction（ XRD）. The results show that the electrical pulse accelerated the migration of sulfate ions in specimens. The amount of specimens with electrical field is 2-4 times as those without electrical field; the decrease of compressive strength with electrical field is 4-10 times as those without electrical field. It shows cement-based materials of urban railway system suffer more severe sulfate attack,so some measures should be taken to prevent and slow down the effect.