硫酸根侵蚀下水泥土力学性能的试验研究

Experimental Study on Compressive Strength of Cement Soil under Sulfate Attack

为探究硫酸根离子侵蚀对水泥土强度的影响,将水泥土浸泡于不同浓度的硫酸和硫酸镁中,通过室内无侧限抗压强度试验对比分析了溶液浓度、龄期对抗压强度的影响。结果表明:水泥土应力应变曲线先接近弹性阶段,随后荷载随位移的增大下降较快;在硫酸和硫酸镁侵蚀下,试样的抗压强度会发生变化,而硫酸镁侵蚀下的抗压强度更小;拟合得到抗压强度与硫酸镁浓度的二次函数;随龄期的增长,水泥土抗压强度增大,硫酸镁的影响使得水泥土的抗压强度减小;镁离子和硫酸根离子共同存在时,腐蚀性增强。

In order to investigate the effect of sulfate ion on the strength of cement soil,cement soil was immersed in different concentrations of sulfuric acid and magnesium sulfate.The effect of solution concentration and age on the compressive strength was analyzed by indoor unconfined compressive strength tests.The results show that the stress-strain curve of cement is close to the elastic phase,and then the load decreases rapidly with the increase of displacement.Under the attack of sulfuric acid and magnesium sulfate,the compressive strength of the sample will change,but the compressive strength under the erosion of magnesium sulfate is smaller.The quadratic function of compressive strength and magnesium sulfate concentration is fitted.With the increase of age,the compressive strength of cement soil increases,the compressive strength of cement soil decreases.Besides,when the magnesium ions and sulfate ions exist together,the corrosiveness will be enhanced.