On the prediction of bolted single-lap composite joints

A new set of failure criteria to predict composite failure in single-lap bolted-joints is proposed. The present failure criteria are an extension of Chang–Lessard criteria considering a three-dimensional stress field and including out-of-plane failure modes. The advantage with respect to other three-dimensional failure criteria is the consideration of non-linear shear stress–strain relationship. The failure criteria were implemented in a finite element model and validated through comparison with experiments in literature. Stresses were calculated by a non-linear finite element model developed in ABAQUS/Standard which considers material and geometric nonlinearities. A progressive damage model was implemented in a USDFLD subroutine. The model predicted the effect of secondary bending and tightening torque showing an excellent agreement with experimental results. Moreover, results were compared with those reported in literature using Hashin failure criteria. In addition, a parametric study was carried out to analyse the influence of friction coefficient and tightening torque.