Stability of Slurry Trenches with Inclined Ground Surface

Abstract

AbstractA method for assessing stability of slurry trenches within an inclined ground surface is presented using the Coulomb-type force equilibrium method. The influence of ground surface inclination on trench stability and angle of critical failure surface is investigated via parametric studies on an example trench. As expected, the factor of safety decreases considerably with an increase in the ground surface inclination. It is shown that it is unconservative to neglect ground surface inclination while analyzing trench stability. According to the example, no significant error in the minimum factor of safety is introduced by using the failure surface inclination angle of 45°+ϕ′/2 for trenches with an inclined ground surface. It is also found that differences between the angle of critical failure surface and 45°+ϕ′/2 may exist; therefore, the angle of the critical failure surface needs to be determined instead of using 45°+ϕ′/2 for the design of remedial measures.