RESPONSE OF PLATE AND SHELL STRUCTURES DUE TO LOW-VELOCITY IMPACT

The dynamic response of isotropic and laminated composite plate and sh ell structures under low velocity impact have been investigated using nine-node degenerated shell elements with assumed shear and membrane s train fields to model the target. The effects of large displacement an d change in thickness have been included during the formulation proces s of the shell element. The incremental form of governing equations is formulated based on the Updated Lagrangian approach where the effects of geometric nonlinearities as well as permanent deformation of targe t are accounted for. Both the Hertzian contact law and experimental in dentation law are incorporated into the finite element program to esta blish the contact force history. Numerical examples on isotropic and c omposite laminated plate and shell structures under low velocity impac t are presented.