On the prediction of bolted single-lap composite joints

Abstract

a b s t r a c tA new set of failure criteria to predict composite failure in single lap bolted joints is proposed. The pres ent 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 imple mented 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 con siders 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 excel lent agreement with experimental results. Moreover, results were compared with those reported in lit erature using Hashin failure criteria. In addition, a parametric study was carried out to analyse the influence of friction coefficient and tightening torque.

Analysis of Bolted Flanged Panel Joint for GRP Sectional Tanks

“…Increasing bolt preload does not lead to significant increase in frictional forces due to the low coefficient of friction between the composite panels hence not significantly improving the slip resistance of the joints. This explains why there is no significant effect on the deflection and stress levels in the panels with increasing bolt preload [34,35].…”

Numerical investigation on the effect of externally exerted loads on particular bolts forces in the multi-bolted flange joint

“…• bez udziału śruby, z oddziaływaniem siłowym napięcia wstępnego [5,35], • płaskie [33,34], • ze śrubą modelowaną za pomocą elementu typu GAP [18], • ze śrubą, w której trzpień śruby modeluje się jako element belkowy, natomiast jej łeb -jako element odkształcalny lub sztywny [15,21,22], • przestrzenne [24,27,36].…”

Static and Fatigue Failure of Bolted Joints in Hybrid Composite-Aluminium Aircraft Structures

“…Based on this expression, Chang and Chang [69] and Chang and Lessard [70], proposed another criterion, in which shear strain-stress nonlinearity [71] was included in form of a third-order polynomial. Further modifications, as including the out-of-plane stresses were introduced by Olmedo and Santiuste [72]. This criterion is used in Paper II of this thesis, in the context of FE-modelling of bolted joint failure using solid elements.…”

“…The stiffness terms are chosen depending on the failure mode, but the reduction level to which they are reduced is somewhat arbitrary. The approach has been implemented in bolted joint models in a number of studies [72,[76][77][78][79][80] and has also been used in Paper II.…”

“…They range from 2D models with rigid pins representing the bolt [78,105,106], to 3D solid models with or without damage development in the composite [47,52,72,76,80,103,[107][108][109][110][111] and they include parameters such as bolt pretension, bolt clearance, the effect of countersunk/protruding bolt heads, different failure initiation and damage progression models, by-pass loading, implicit/explicit solution methods etc. This work includes solid models of countersunk single-lap joints, cf.…”