Limit equilibrium analysis for effect of strength parameter of side slope on stability

In order to study the effect of the shear strength parameters of rock and soil on the stability of side slope, both theoretical derivation and calculation with Bishop limit equilibrium method were adopted to change the cohesive force c and internal friction angle φ of rock and soil, respectively. And the variation of both safety factor and sliding surface of side slope was discussed. The results show that when the cohesive force or internal friction angle changes, the safety factor of side slope will change. However, the variation of sliding surface is affected by the function η cφ which is related to the cohesive force and internal friction angle. When η cφ is a constant value, the sliding surface will not change with the variation of shear strength parameters. When η cφ increases, the sliding surface of side slope will move from the near slope surface to the inside of side slope gradually. Inversely, when η cφ decreases, the sliding surface of side slope will move from the inside of side slope to the near slope surface. The present results can provide the references for the theoretical and practical investigation in the stability of side slope.