Slope stability analysis by strength reduction method based on average residual displacement increment criterion

The strength reduction method (SRM) is one of the main methods for evaluating slope stability and its key step is to select failure criteria reasonably and correctly. At present, non-convergence of numerical iteration, penetration of plastic zone, and the catastrophe of characteristic points displacement are usually used as slope failure criteria. To avoid the randomness of selecting characteristic points and the subjective error, this paper presents a new criterion: residual displacement increment criterion based on the displacement catastrophe criterion of characteristic points. In this criterion, the average residual displacement increment is calculated after each reduction, and the strength reduction factor corresponding to the maximum average residual displacement increment is regarded as the safety factor of the slope. This new criterion avoids the randomness of selecting characteristic points and the subjective error of judging the displacement mutation point artificially. The two-dimensional slope stability calculated by this criterion is compared with the other three criteria and Spencer method, which verifies the applicability and accuracy of this criterion.