Dynamic Analysis of Influence of Soil Damping Nonlinearity on Foundation Stability

Abstract

Aiming at the sliding instability problem of foundation-based system under the action of earthquake and other dynamics, nonlinear cusp catastrophe analysis model which conforms the actual working behavior of foundation-based system is established by using the catastrophe theory. It describes the whole process of catastrophic instability of the system and analyze the basic stability. Based on the research of many nonlinear factors contained in the system that has been considered so far, the inherent influence of the nonlinear factors of soil damping in the actual working environment is considered and analyzed for the first time. Under the linear, quadratic and cubic nonlinear conditions, the most general expression of soil damping reflecting the system’s instability and catastrophe of the system bifurcation set is derived. The results show that the nonlinear characteristics of damping directly affect the correct evaluation of the ultimate bearing capacity of the foundation. Although ignoring the nonlinear influence of damping will not change its catastrophic properties, but will underestimate the ultimate bearing capacity of the foundation.