Establishment of direct shear strength model of river sand and its application in high embankment of sand

Sand is generally considered to be cohesionless material, but there is small cohesion for sand with certain moisture content. It is reasonable to consider the cohesion when analyzing the stability of side slope of high sand embankment. In this paper, direct shear tests of the Shuhe River sand (in Shandong province, China) were done at different moisture contents and dry densities, and a multiple regression equation of shear strength was established based on the test results. The strength parameters (including cohesion and internal friction angle) at the given moisture contents and dry densities could be predicted according to the established regression equation. Based on this, the side slope stability of high sand embankment under different wet conditions was analyzed with the shear strength reduction method (SSRM).Results showed that the high embankment of sand with slope of 1:1.5 and edge thickness (weathered rock materials) of 2.0 meters was stable.