可溶盐离子对高含盐水泥土强度影响的机理分析

Mechanism Analysis of Influence of Soluble Salt Ions on Strength of Salt-rich Cement-soil

通过室内不同龄期水泥土无侧限抗压强度试验,探讨了高含盐水泥土中Mg2+、Cl-、SO42-离子含量变化对水泥土强度的影响,并借助X射线衍射技术和电子扫描显微镜来研究可溶盐离子引起水泥土强度增长的过程和机理。研究结果表明:Mg2+、Cl-、SO42-离子对水泥土强度有不同的负面影响,且离子含量越高负面影响越大;Mg2+、Cl-、SO42-离子不仅改变水泥土微观结构,而且抑制C-S-H和C-A-H的生成,从而导致水泥土强度降低。

Through laboratory test of cement-soil＇s unconfined compressive strength, the influence of Mg^2＋ ,Cl and SO4^2- content on the strength of salt-rich cement soil was explored, and the process and mechanism of causing the increase of salt-rich cement-soil＇s strength were studied through X-ray diffraction and scanning electronic microscopy （SEM）. The research results show that Mg2＋ ,Cl^- and SO4^2- have negative influence on cement-soil＇s strength and the higher the ion content is, the greater the negative effect is; Mg^2＋ ,Cl^- and SO4^2- not only change cement-soil＇s micro-structure, but also restrain the formation of C-S-H and C-A-H, which result in the decrease of cement-soil＇s strength.