A numerical procedure has been developed to investigate the nonlinear and strain-rate-dependent deformation response of polymer matrix composite laminated plates under high strain-rate impact loadings. A recently developed strength of materials based micromechanics model, incorporating a set of nonlinear, strain-rate-dependent constitutive equations for the polymer matrix, is extended to account for the transverse shear effects during impact. Four different assumptions of transverse shear deformation are investigated to improve the developed strain-rate-dependent micromechanics model. The validities of these assumptions are investigated using numerical and theoretical approaches. A method to determine through the thickness strain and transverse Poisson’s ratio of the composite is developed. The revised micromechanics model is then implemented into a higher-order laminated plate theory that is modified to include the effects of inelastic strains. Parametric studies are conducted to investigate the mechanical response of composite plates under high strain-rate loadings. Results show that the transverse shear stresses cannot be neglected in the impact problem. A significant level of strain-rate dependency and material nonlinearity is found in the deformation response of representative composite specimens. I. Introduction T HERE is a growing need in military and civil applications for composite materials that not only have good structural characteristics, but that also have good penetration resistance and greater strength after impact. Polymer matrix composites are very susceptible to projectile impact such as fragments, flying debris, or a failed rotor blade. If not contained, a projectile traveling at ballistic velocity could penetrate a polymer matrix composite plate or shell and cause fires, hull damage, occupant injury, and component malfunction. For example, an engine containment system must be capable of containing fragments traveling at ballistic velocities from a failed fan blade. Also, such an impact event may compromise the structural integrity of the composite and lead to catastrophic failure. Thus, it is important to develop the ability to predict the deformation and failure behavior of polymer matrix composites subject to high strainrate loading conditions. An analysis methodology must be able to account for any strain-rate effects, material nonlinearities, and transverse shear effects that may be present in the impact problem. Also, the computational efficiency is critical in the numerical analysis of such a problem. The objective of this work is to develop an efficient numerical framework for the analysis of engine containment systems made of polymer matrix composites that addresses the issues just discussed.