Ultimate Bearing Capacity Analysis of a Super-Long Rock-Socketed Filling Pile Based on Catastrophe Theory

Abstract

Based on the catastrophe theory of nonlinear science, a cusp catastrophe model of a super-long pile under axially load is established, and the vertical ultimate bearing capacity expression of super-long pile is derived. By fitting pile load-settlement field test data, the coefficients of a hypothetical super-long pile load-deformation curve and the value of ultimate bearing capacity are obtained. The results show that: the cusp catastrophe model is applicable to the determination of ultimate bearing capacity, and can be used to predict the buckling failure of a super-long pile. In addition, a fold catastrophe model is established to investigate the effects of plastic softening on the ultimate bearing capacity. The derived ultimate bearing capacity expression implies that the radius of the elastic and the plastic softening zones are relevant to the ultimate bearing capacity.