Coupling Boundary Element Reliability Algorithms applied to Probabilistic Analysis of Crack Propagation in Structures subject to Fatigue

摘要

This paper presents a coupled model using the boundary element method and thernreliability algorithms for the analysis of probabilistic crack growth. Fatigue andrncrack propagation are phenomena affected by high uncertainties, whererndeterministic methods fail to predict accurately the structural life. The boundaryrnelement method has been recognized as an accurate and efficient numericalrntechnique in modelling mixed mode crack propagation, which is very interesting forrnreliability analysis. The coupled procedure allows us to consider uncertainties duringrnthe crack growth process. In addition, it calculates the probability of fatigue failurernfor complex structural geometry and loading. Two coupling procedures werernconsidered: direct coupling between reliability algorithm and mechanical solver andrnindirect coupling using the response surface method. Numerical examples show thernperformance of the proposed models in lifetime assessment under uncertainties.