ABSTRACT

The dynamic response of a mild steel beam under repeated impacts is experimentally investigated. Repeated impacts are conducted on a drop weight machine, during which the impact mass and impact velocity are kept constant. The impact force, velocity of the indenter, displacement, and absorbed energy are obtained. The impact process between the indenter and the specimen is illustrated. Pseudo-shakedown phenomenon was observed during the repeated impacts. When a pseudo-shakedown state is reached, the beam behaves almost the same under each subsequent impact. The maximum contact force, maximum displacement of the beam, rebound velocity of the striker, contact time, all of them reach a constant value respectively and the permanent displacement of beam will not increase further more.