Experimental and numerical studies of impacts on stainless steel plates subjected to rigid missiles at low velocity

Abstract In the study of nuclear power plant safety, particular attention must be paid to the eventuality of accidents during handling operations. It can be assumed that such accidents will involve the fall of a body, which may possibly be extremely massive, on the reactor structures. Impact velocity would tend to be relatively low (in the region of 10 m/s) but the amount of energy released may be great. In order to gain a fuller understanding of the problem, a series of tests has been conducted followed by numerical analysis to find the best models for the observed behaviour. Tests have been carried out by the CEA on circular stainless steel plates 467 mm in diameter and 4 to 10 mm thick, subjected to the effect of a rigid missile falling freely from a height of 2 to 6 m. The missile, which was ballasted to obtain a mass ranging from 100 and 250 kg, was a flat-nosed cylinder with a diameter of between 30 and 90 mm. Tests were carried out at increasing energy to determine the exact value at which a piece was punched out of the plate. The purpose of the tests was to make it possible to evaluate the effects of the different parameters involved in punching. They also offered the advantage of providing simple data which could easily be used to develop a numerical model for punching.