黏土力学性能及干湿循环下的边坡稳定性数值模拟研究

雷 齐善
长江大学 城建学院 湖北荆州 434023

摘要

利用数值模拟和剪切实验的研究方法，在不同干湿循环次数和不同初始干密度的条件下，受干湿循环作用对黏性土抗剪强度的影响，对土样的剪切和结构特性进行了研究，结果表明：1）直接剪切试验中，在第一次干湿循环时，抗剪强度显著下降，随着循环次数的增加，抗剪强度在干燥时比湿透时要大。2）在数值模拟中，土质边坡的稳定性随着干湿循环次数的增加而逐渐降低，随着干湿循环次数的减少而逐渐提高，同时也增加或减少了边坡的最大移位。3）当降雨作用下黏土边坡含水量增加时，边坡最大位移大大增加，加速度导致边坡不稳定，受干湿循环影响，含水量增加，安全系数显著降低，导致边坡稳定性明显下降，同时边坡最大位移也达到极大值。

关键词

抗剪强度;干湿循环;边坡稳定性;数值模拟

参考

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