Reliability analysis of a woven composite Pi-joint structure

Abstract

The finite element (FE) method combined with multicontinuum theory (MCT) for analyzing composites was coupled with reliability analysis to develop a probabilistic, progressive failure, multiscale analysis of a three-dimensional braided composite Pi-joint subject to shear loading. The constituent engineering constants, ply strengths, and structural geometric parameters were treated as random variables. Failure was defined in the progressive failure framework as a minimum structure stiffness. NESSUS reliability analysis, HELIUS MCT, and Abaqus® FE analysis software packages were interfaced to create a global framework for performing multiscale reliability analysis of the composite structure. The reliability analysis resulted in the calculation of the probability of failure and sensitivities of the probability of failure to the random variables defined in the model. The model's probability of failure was most sensitive to the geometric parameters defining the thickness of the upright portion of the Pi-joint and the depth of the Pi-joint. The model's response was also sensitive to the compressive strength of the composite.