呼伦贝尔沙质草原表土物理力学性质

Top Soil Texture,Physical and Mechanical Property of the Hulunbuir Sandy Grassland,Inner Mongolia,China

通过野外现场调查、载荷试验、轻型圆锥动力触探及室内试验,对呼伦贝尔沙质草原厚度30cm的表层沙土物理力学性质及承载力、剪切变形特征进行研究。结果表明:表层沙土工程分类为细砂,颗粒级配不良,沿深度有明显分层;干密度1.34~1.51g·cm-3,黏聚力12~27.4kPa,内摩擦角22.5°~24.0°,变形模量8.5 MPa;各指标表明沙土的工程性质上部差于下部;沙土承载力特征值和极限承载力分别为150kPa和300kPa,承载力不足导致表层沙土发生冲剪破坏(塑性破坏)和整体剪切破坏(脆性破坏)。

Research into topsoil texture,physical and mechanical properties within the depth of thirteen centimeters has been carried out based on field survey and laboratory tests on bearing capacity and shear deformation analysis in the sandy grassland of Hulunbuir,Inner Mongolia.It is discovered that the topsoil could be named fine sand,with poor grain size distribution,and layered structure.Soil dry density is between 1.34 g·cm-3 and 1.51 g·cm-3,soil cohesive forces between 12 kPa and 27.4 kPa,soil internal friction angle falls between 22.5°and 24°,and soil modulus of deformation is 8.5 MPa.It was discovered that the soil engineering property of the lower bed is better.Top soil characteristic value of bearing capacity was150 kPa,and its ultimate bearing capacity was 300 kPa.Punching shear destruction(The plastic damage)and General shear failure(Brittle failure)is usual as soil carrying capacity is weak.