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A generalized analytical formulation is presented for the prediction of ballistic impact behavior of 2D woven fabric composite laminates impacted with a rigid cylindrical projectile. The formulation is valid for a wide range of laminate thicknesses. The formulation is based on stress wave propagation and energy balance between the projectile and the composite target. During the ballistic impact event, the energy lost by the projectile is absorbed by the target through various damage and energy absorbing mechanisms such as compression of the target directly below the projectile, compression in the region surrounding the impacted zone, shear plugging, stretching and tensile failure of yarns/layers in the region consisting of primary yarns, tensile deformation of yarns/layers in the region consisting of secondary yarns, conical deformation on the back face of the target, delamination, matrix cracking, and friction between the projectile and the target. The formulation presented considers both shear plugging and tensile failure during conical deformation. Solution procedure for the evaluation of ballistic impact performance is presented. Experimental validation is performed on the ballistic impact behavior of two types of composite specimens: 2D plain weave E-glass/epoxy and 2D 8H satin weave T300 carbon/epoxy. Typical results on ballistic limit velocity and energy absorbed by various mechanisms are presented.

Performance of three-dimensional orthogonal woven E-glass/epoxy composites under high velocity impact is presented. The analytical method used is based on wave propagation and energy balance between the projectile and the target. Different damage and energy absorbing mechanisms for a typical three-dimensional orthogonal woven composite are compression of the target directly below the projectile, compression in the surrounding region of the impacted zone, tension in the region consisting of primary yarns, tensile deformation in the region consisting of secondary yarns, shear plugging, bulge formation on the back face of the target, matrix cracking and friction between the target and the projectile. Experimental studies are also presented on high strain rate characterization, shear plugging behavior and high velocity impact behavior. For comparison, studies are also presented on the performance of two-dimensional plain weave E-glass/epoxy composites. A good match is observed between the analytical predictions and experimentally obtained limit velocities for complete penetration. It is observed that limit velocity for complete penetration for threedimensional woven composite is higher than that for two-dimensional plain weave composite.

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