Polygonal slip surface

The program performs stability analysis of rock blocks moving along the polygonal slip surface. Owing to the complexity of the general solution the program admits the following assumptions:

• motion of rock blocks is only translational
• blocks translate along the polygonal slip surface formed either by planar planes or planes with moderate waviness
• rock blocks are divided by joints with known directions
• actual deformation of rock mass inside the blocks is negligible
• failure on the polygonal slip surface and along joints is driven by the Mohr-coulomb failure criterion
• the same factor of safety is assumed for all joints and along the entire polygonal slip surface
• all rock blocks are in contact (opening of joints is not allowed)
• the shear forces on the polygonal slip surface have the same sign

The Mohr-Coulomb shear strength parameters on the slip surface and on joints separating individual block are the main input data for the determination of stability of rock blocks. The solution is further influenced by the weight of block (depends on the geometry and bulk weight of rock), anchorage, surcharge, influence of water and seismic effects.

The basic theoretical grounds of the solution are described here.

Polygonal slip surface

Literature:

Rock mechanics 8, Stabilitätsberechnung ebener und räumlicher Felsböschungen,1976, pp. 73 – 113