NONLINEAR IMPACT ANALYSIS OF LAMINATED CYLINDRICAL AND DOUBLY-CURVED SHELLS

The nonlinear impact response of laminated composite cylindrical and d oubly curved shells is analyzed using a modified Hertzian contact law. A finite element model is developed based on Sander's shell theory an d includes shear deformation effects and nonlinearity due to large def lection. A nine noded isoparametric quadrilateral element is used to m odel the curved shell. The nonlinear time dependent equations are solv ed using an iterative scheme and Newmark's method. Numerical results f or the contact force and center deflection histories are presented for various impactor conditions, shell geometry and boundary conditions.