Probabilistic Finite Element for Fracture Mechanics

摘要

This paper presents a probabilistic methodology for fracture mechanics analysis of cracked structures. The main focus is on probabilistic aspect which related the nature of crack in material. The methodology involves finite element analysis; statistical models for uncertainty in material properties, crack size, fracture toughness and loads; and standard reliability methods for evaluating probabilistic characteristics of fracture parameter. When a crack is observed, the problem is to know whether it is suitable to repair the structure as a priority or if it can be justified that an accident will not occur. Therefore, the probabilistic analysis can provide the failure probability knowing that there is a crack and that the load can reach accidental values defined in a particular range. The probability of failure caused by uncertainties related to loads and material properties of the structure is estimated using Monte Carlo simulation technique. Numerical examples are presented to show that probabilistic methodology based on Monte Carlo simulation provides accurate estimates of failure probability for use in fracture mechanics.