THE EFFICACY OF THE MOMENTUM BALANCE METHOD IN TRANSVERSE IMPACT PROBLEMS

An elastic-plastic contact law that incorporates local permanent defor mation in the contact zone has been used to investigate the efficacy o f the momentum balance method in transverse impact problems. The momen tum balance solution is compared to the numerical solution of the same equations using the contact law. It is shown that the momentum balanc e method gives very good results for the post impact behavior of both the impacter and the beam. In certain cases, it is also shown to yield satisfactory results for the dynamic behavior during contact. It is d emonstrated that the momentum balance method with an appropriate coeff icient of restitution obtained from the contact law, is physically the same as using the contact law itself, with the difference that the lo cal deformation is neglected.