Dynamic response of anisotropic sandwich panels to underwater and in-air explosions

A study devoted to the dynamic response of sandwich panels to underwater and in-air explosions is presented. The study is carried out in the context of a geometrically nonlinear model of sandwich Structures featuring anisotropic laminated face sheets and a transversally compressible orthotropic core. The unsteady pressure generated by the explosion and acting on the face of the sandwich panel includes the effect of the pressure wave transmission through the core. Its implications on the structural time-histories as corresponding to the underwater and in-air explosions are put into evidence. The effects of the transverse core compressibility on dynamic response are highlighted. In this sense, one of its major implications is the possibility to capture interactively the global and local (wrinkling) dynamic response of the panel. It is shown that implementation of the structural tailoring technique in the face sheets can constitute an important mechanism toward enhancing the dynamic load carrying capacity of sandwich panels when exposed to blast pulses. Effects of the core, as well as the ones due to the ply-thickness, combined with that of ply-angle and stacking sequence of face sheets, orthotropy of the material of the core, geometrical nonlinearities, initial geometric imperfections and of the damping ratio are investigated, and their implications upon the dynamic response are highlighted and pertinent conclusions are outlined.