卢氏膨胀岩膨胀和强度试验研究

为了探讨不同初始含水量对卢氏膨胀岩的膨胀前后剪切强度的影响,以卢氏膨胀岩为研究对象进行了膨胀岩膨胀变形和直剪试验。试验结果表明:膨胀应变和膨胀压力随初始含水量的增加而减小;膨胀压力与初始含水量之间存在明显的负线性关系并建立了适用于卢氏膨胀岩的膨胀模型;对于膨胀前的膨胀岩随着初始含水量的增加,膨胀岩的剪切强度参数显著降低;膨胀后的膨胀岩剪切强度比膨胀前显著下降,表现为随初始含水量的增大粘聚力增大而内摩擦角基本保持不变的规律。

Study on Water Swelling and Softening Characteristics of Expansive Rock

In order to investigate the influence of different initial water content on the shear strength of the expansive rock before and after expansion,the expansion deformation and direct shear test of the expansive rock were carried out with the expansive rock as the research object.The test results show that the expansion strain and expansion pressure decrease with the increase of initial water content;there is a significant negative linear relationship between expansion pressure and initial water content and an expansion model suitable for expansive rock is established;With the increase of initial water content,the shear strength parameters of expansive rock decreased significantly.The shear strength of expanded expansive rock decreased significantly compared with that before expansion,which showed that the cohesive force increased with the increase of initial water content and the friction angle remains basically the same.