Effects of temperature on the response of composite bolted joints

Development of experimental and numerical methodologies for the investigation of composite and hybrid metal-composite fastened joints subjected to impact loads

“…Typical matrix microcracks within a composite carbon/epoxy system of a bolted joint, close to the hole region, are illustrated in Figure 2-3 [22].…”

“…Composite bolted joint microscopic failure modes near the bearing zone (with M is denoted the matrix microcracking, while D and K indicate delamination and kink-band formation respectively) [22].…”

“…With respect to the damaged surfaces, tensile delamination is characterized by regions of smooth tensile matrix failure and river or chevron matrix markings, while shear delamination presents cusps or hackles [8,31,32]. Many experimental works indicated the significant contribution of delamination damage regarding the structural response and failure behaviour of composite fastened configurations [8,21,22,[33][34][35]. In particular, this type of failure does not appear only under bearing loading, which mainly results in compressive stresses around the hole in lap joint designs [21,22,34], but also under tensile or compressive loads in pull-through (or pull-out) joint configurations (out-ofplane loading cases) [8,33] and filled hole laminated coupons (pure in-plane loading cases) [34,35].…”

“…Many experimental works indicated the significant contribution of delamination damage regarding the structural response and failure behaviour of composite fastened configurations [8,21,22,[33][34][35]. In particular, this type of failure does not appear only under bearing loading, which mainly results in compressive stresses around the hole in lap joint designs [21,22,34], but also under tensile or compressive loads in pull-through (or pull-out) joint configurations (out-ofplane loading cases) [8,33] and filled hole laminated coupons (pure in-plane loading cases) [34,35]. Furthermore, in similar experimental campaigns [34,36,37] it was reported that the stacking sequence and the washer/fastener clamping forces can affect the bearing strength, as well as the delamination initiation and propagation.…”

“…Numerous experimental campaigns followed the above pioneering works making a significant contribution in the field of composite fastened joints behaviour [21,22,34,36,37,[156][157][158][159][160][161][162][163]. A big part of these works has been conducted in the frame of the European research program 'Bolted Joints in Composite Aircraft Structures (BOJCAS)', which was coordinated by the Limerick University.…”