RELIABILITY MODELS FOR CRACK PROPAGATION ANALYSIS BY USING THE BOUNDARY ELEMENT METHOD

Resumo

This work presents a crack propagation analysis using an alternative boundary element
method (BEM), in both deterministic and probabilistic approach. The fracture effects are captured
using an initial stress field, this procedure leads to the appearance of a variable called dipole and
responsible for representing the cohesive zone. Both geometry and fracture boundary are discretized
using linear elements, the fracture elements are discontinuous. Regarding the structural reliability
analysis, the boundary element formulation was coupled with the reliability algorithms for
probabilistic analysis of crack problems. The fracture parameters are treated as random variables. First
Order Reliability Method (FORM) is used in order to evaluate the reliability index and the failure
probability for fractured problems. A comparative study between the Monte Carlo simulation
technique are performed. Numerical examples are presented in order to show the accuracy of the BEM
formulation in crack propagation analysis, as well in the assessment of structural reliability in two
dimensional problems.