CRASHWORTHINESS ANALYSIS OF A LOCK GATE IMPACTED BY THREE DIFFERENT RIVER SHIPS

This paper presents a study of the crashworthiness of the Pierre Bénite lock gate using a FEM approach. This gate situated in the Rhône river (south of Lyon) is collided by three different river ships : - a 6000 DWT convoy of barges with an initial velocity of 1m/s, - 3500 DWT carrier Rhône-Liner with an initial velocity of 1m/s, - a 2200 DWT passenger vessel with initial velocities of 1m/s and 2m/s. An analytical elastic analysis of the crashworthiness of a lock gate was carried out by J.C Rodet for the «Compagnie Nationale du Rhône». This analysis showed that : - the kinetic energy of a river ship which impacts a lock gate with a velocity of 1m/s is not entirely dissipated by the elastic energy of the lock gate, - the lock gate elastic response may result in dangerous reaction forces at the supporting chains, - empirical or analytical methods [2] generally used to determine the impact forces and resulting indentations of struck ship hulls may be applied to the lock gate but they have to be validated by a non-linear finite element analysis. An overview of the elastic analysis is presented in section 2 below. As we found that an elastic analysis was insufficient to quantify the damage, we decided to conduct a numerical analysis (section 3).