IMPACT OF COMPOSITE STRUCTURES - THE MOMENTUM BALANCE METHOD

The momentum balance method which is based on the impulse momentum pri nciple is used to study the transverse impact of a simply supported co mposite beam. In this method the effects of local contact behavior is accounted for through the use of an appropriate coefficient of restitu tion obtained from an elastic-plastic contact law. This greatly simpli fies the problem by decoupling the equations of motion, and for the pr oblem studied, facilitates an analytical solution. The momentum balanc e solution is compared to the numerical solution of the same problem u sing the nonlinear elastic-plastic contact law. The proposed method gi ves very good results for the post impact behavior of both the impacte r and the beam. In certain cases, it yields satisfactory results for t he dynamic behavior even during contact. The momentum balance method, with an appropriate coefficient of restitution obtained from the conta ct law, is physically the same as using the contact law itself, with t he difference that the local deformation is neglected.