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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.

An analytical formulation is presented for the prediction of ballistic impact behavior of fabric targets. The formulation is based on stress wave propagation in porous medium and energy balance between the rigid projectile and the fabric target. During the ballistic impact event, energy lost by the projectile is absorbed by the fabric target through various damage and energy absorbing mechanisms such as compression of the fabric 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 fabric target, in-plane friction between the warp and fill yarns and through the thickness friction between the moving projectile and the fabric target. The formulation presented considers both shear plugging and tensile failure of yarns during conical deformation and is valid for a wide range of fabric target thicknesses. Solution procedure for the evaluation of ballistic impact performance is presented. Further, experimental results are presented for the validation of analytical predictions. A good match is observed between the analytical predictions and the experimental results.