Closed form solution of planar rock slope stability under Hoek and Brown (1980) failure criterion and non-associative plasticity

摘要

Rock slope stability is analysed assuming toe planar failure surfaces. Dimensionless magnitudes and the non-linear Hoek and Brown (1980) strength law are used. The strength law, which is verified by the stresses on the failure plane, is established depending on dilatancy. Constant dilatancy angles are assumed. The angle of dilatancy values are fixed depending on the degree of fracturing and weathering of the rock mass following Hoek and Brown (1997) recommendations. Under Spencer's assumptions (1967), a close form mathematical solution is obtained when Δx → dx. The relationships between slope height, slope inclination with its safety factor are provided. These values are compared, with the same input data: a) with the results obtained from the computer calculations using a well-known software code and b) with other simplified methods.