Static and fatigue behaviour of sandwich composite panels joined by blind fasteners

An experimental investigation has been carried out to estimate the static and fatigue behaviour of specimens made up of steel plates joined with sandwich composite panels by blind fasteners. A first set of pull-out and shear static tests has been performed using sandwich panels composed of a nomex honeycomb core between two laminates of glass/graphite/kevlar fibres in epoxy matrix. To fully estimate the performances of this kind of joint, pull-out and shear fatigue tests have been carried out in order to mark up the effect that reinforcement type and core thickness have on S-N curves of joints. Despite the scattered data, it was even possible to draw a single rather narrow band to deal with fatigue design analyses of all kinds of tested joints.