Probabilistic structural stability prediction

Abstract

In this paper, an efficient reliability analysis method for durability of structural components subjected to external and inertia loads with time-dependent variable amplitudes is presented. This proposed method is able to support reliability analysis of crack initiation and crack propagation lives of practical applications, considering uncertainties such as material properties, manufacturing tolerance, and initial crack size. Three techniques are employed to support the probabilistic durability prediction: (i) strain-based approach for multi-axial crack initiation life prediction and linear elastic fracture mechanics (LEFM) approach for crack propagation life prediction, (ii) statistics-based approach for reliability analysis, and (Hi) sensitivity analysis and optimization methods for searching the most probable point (MPP) in the random variable space to compute the fatigue failure probability using the first-order reliability analysis method (FORM). A two-point approximation method (TPA) is employed to speed up the MPP search. A tracked vehicle roadarm is presented to demonstrate feasibility of the proposed method.