Numerical Analysis of Dynamic Responses of Dam Gate Pier Structures Subjected to Ship Collisions

The global shipping industry has experienced rapid development in recent years, leading to increased ship impact hazards for bridge and hydraulic structures. In contrast to bridge piers, there is much less information about ship collision-induced responses of dam gate piers. The aim of this work is to explore ship impact behavior of gate piers of dams in different ship collision scenarios. A coupled acoustic-structure interaction methodology is used to carry out the numerical simulation work. After validation against empirical impact force predictions, parametric analyses are carried out to identify key factors influencing the ship collision response of the pier. Three key factors are identified: the ship weight, ship speed and impact angle. However, it is found that the impact behavior of the pier shows minimal sensitivity to the water level variations. The impact response of the pier is more sensitive to the ship speed variation than to the mass change while the momentum remains constant. This case study has shown that over 80% of the initial kinetic energy of the ship is dissipated through the hull deformation. The damage to the gate pier is relatively minor and localized, but the transient displacement at the gate hinge exceeds the permissible standard. Overall, this study strengthens the idea that controlling pier displacements should take precedence in ship impact scenarios. Post-collision inspections for gate piers should prioritize checking for excessive deformation of the gate hinge assemblies and potential water leakage in the transverse joints or at the gate side seals. Taken together, this study implies that gate piers of dams of conventional dimensions possess adequate resistance to normal ship collisions.