Similarity laws of structures under impact load: Geometric and material distortion

Recent developments of similarity laws in structural impact have focused on methods of altering the impact velocity to overcome strain-rate effects and differences in material mechanical properties. The present study shows a more comprehensive framework where density, material properties and small thickness distortion are all taken into account when relating scaled models to prototypes under impact loads. The procedure is applied to using theoretical solutions of impact loaded structures such as beams, circular plates and a double plate structure. In addition, numerical simulation is performed to assess the behaviour of a double plate structure, circular plates under impact and impulsive loading. Results have shown that differences in density, strength properties as well as thickness distortions can all be compensated by respecting dimensionless number based on plastic bending moment M-0 and mass ratio. This allows one to predict the response of a large structure by testing a small scale model, even when they are made of different materials.