Collision energy absorption of ships' bow structures

The energy absorbed during the collapse of ship's bow structures in a collision is largely due to the plastic work done by axial crumpling of the plate elements in the structures. In this paper a method is presented for predicting crushing strength of ships' bow structures during a collision.The method of predicting the crushing strength of a variety of structural elements is described using the kinematic method of plasticity. Effects of strain-rate on the axial of crushung of structural elements are included. The crushing strenght of a ship's bow structure is obtained by summing the energy dissipated in all individual structural elements. The theoretical predictions are compared with experimental results for ships' bow models. The paper concludes with an example of the application of the theoretical method to a ship collision with a concrete pier.