土壤含水率对浅层滑坡体不同层次土壤抗剪强度的影响

采用5种土壤质量含水率(0.05,0.08,0.10,0.12,0.15)水平,进行浅层滑坡体不同层次土壤在不同含水率条件下的不固结不排水剪切试验.试验表明,浅层滑坡体不同层次土壤抗剪强度与土壤含水率密切相关.土壤含水率对浅层滑坡体A层、B层和C层土壤抗剪强度指标的影响呈现出相同的规律.A层、B层和C层土壤黏聚力均随着土壤含水率的增加基本呈先增大后减小的趋势,在土壤含水率为0.10左右时土壤黏聚力达到其最大值,在相同土壤含水率条件下,土壤黏聚力的分布规律为C层>B层>A层.A层、B层和C层土壤内摩擦角随着土壤含水率的增加近似呈线性减小,在相同土壤含水率条件下.土壤内摩擦角的分布规律为C层>B层>A层,但就随土壤含水率的增加,土壤内摩擦角减小的速率而言,呈现出B层>A层>C层的规律.消除和减轻地表水的危害是我国西南丘陵山地滑坡灾害防治的重要环节.

Effects of Soil Water Content on Soil Shearing Strength to Different Soil Layer of Shallow Landslide

The triaxial shearing test under unconsolidated-undrained condition was carried out in laboratory with five soil water content(W/W)of 0.05,0.08,0.10,0.12,0.15 for different soillayer of shallow landslide.Experimental data indicated that there was close relation between soil water content and soil shearing strength.Effects of soil water content on soil shearing strength was similar to different soil layer of shallow landslide.Soil cohesive force firstly increased and then decreased with the increasing of soil water content,and it reached to the maximum at the water content of about 0.10.There was C layer>B layer>A layer about soil cohesive force under same soil water content.Soil internal frictional angle decreased linearly with the increasing of soil water content to different soil layer of shallow landslide and there was C layer>B layer >A layer about soil internal frictional angle under same soil water content,but there was B layer>A layer>C layer about the decreasing rate of soil internal frictional angle with the increasing of soil water content.It was the key to fathering landslide that the damage of surface water was eliminated or lightened.