On the contact law and structure responses of sandwich beam subject to low-velocity impact

The paper presented the contact law and structural response of sandwich beam subject to low-velocity impact. Firstly, the upper face sheet of the sandwich beam is assumed as a beam supported on the elastic-plastic foundation. The quasi-static contact law is derived from the equilibrium equation of the beam associated with large deformation and axial tensile stiffness of the upper face sheet, and validated with the structure responses of the sandwich beam fixed on the rigid plate subject to low-velocity impact. Secondly, the structure responses of simply supported sandwich beam with low-velocity impact are investigated by energy-balance model, discrete model and complete model to obtain the impact duration, the history of contact force and the transverse deflection. In addition, the effects of the mass ratio and the initial velocity on the structural responses and the applicability of different models are investigated. The theoretical and numerical results demonstrate that the contact law proposed by present paper is efficient. All the models in the paper can be used to acquire the structural response when the mass ratio is large, and only the complete model can be accurately predict the response when the mass ratio is small or the initial velocity is large, and the impact duration predicted by complete model is not influenced by the initial velocity.