Determination of stability numbers for soil slopes following non-associated non-coaxial flow rule

Abstract

The assumption of an associated flow rule overestimates the volume increase during shear than that is observed for most of the soils and also for an associated flow rule the stresses acting over various rupture surfaces do not appear in the energy rate expressions. For a non-associated non-coaxial flow rule it is essential to define the stresses along the rupture surface to find the rate of dissipation of internal energy. In the present work, stability number for the homogeneous soil slope obeying non-associated non-coaxial flow rule has been determined by defining the stresses along the rupture surface using the assumption of interslice forces as earlier introduced by Fellenius (1936) and Bishop (1955). In the analysis, effects of seismic force have been also incorporated. Optimization methods and neural network have been implemented to obtain the stability numbers. The result indicates that the effect of dilatancy angle (ψ) on the results was seen to be less significant for non-coaxial flow rule. In the neural network analysis genetic algorithm has been used in the training phase to get better results.