PROBABILISTIC STRUCTURAL DURABILITY PREDICTION

An efficient reliability analysis method for durability of structural components subjected to external and inertial loads with time-dependen t variable amplitudes is presented, This method is able to support rel iability analysis of crack initiation and crack-propagation lives of p ractical applications, considering uncertainties such as material prop erties, manufacturing tolerances, and initial crack size, Three techni ques are employed to support the probabilistic durability prediction: 1) strain-based approach for multiaxial crack initiation life predicti on and linear elastic fracture mechanics approach for crack propagatio n-life prediction, 2) statistics based approach for reliability analys is, and 3) 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 ana lysis method, A two-point approximation method is employed to speed up the MPP search, A tracked-vehicle roadarm is presented to demonstrate feasibility of the proposed method.