摘要
为研究排气状态对非饱和土抗剪强度的影响,以云南昆明的红粘土和粉土为试验土样,以不排气不排水和排气不排水为控制条件进行三轴剪切试验。试验结果表明,排气条件下的非饱和土强度相较不排气时有所提高,且排气状态对红粘土抗剪强度的影响程度大于对粉土的影响程度;粘聚力与饱和度的关系呈非规律性,内摩擦角随饱和度的增大而减小;排气不排水条件下,粘聚力和内摩擦角均随干密度的增大而增大。试验结果证实了排气状态对非饱和土体抗剪强度的显著影响。
A series of non-exhaust and exhaust undrained triaxial compression tests was performed on unsaturated red cohesive soil and silty soil in Kunming area for study the influence of exhaust pore air on the shear strength of unsaturated soil.The test results show that the strength of unsaturated soil under the condition of exhaust is stronger than that of non-exhaust condition,and the influence degree of the red clay soil is greater than that of the silty soil.The relationship between cohesion and saturation is nonlinear.The friction angle decreases with increase of saturation degree.Both cohesion and friction angle increase with dry bulk density increasing.These are fully proved that pore air has impact on the shear strength of unsaturated soil.
引文
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