SPH modeling of dynamic impact of tsunami bore on bridge piers

• Mesh-free method is able to simulate a realistic free surface profile during bore-pier interaction
• Accurate prediction of the tsunami bore hydrodynamic force on the bridge pier
• Accurate prediction of the tsunami bore velocity field around the bridge pier
• Hydrodynamic force separation into the drag effect and the blockage effect
• Prediction of bed shear stress around a bridge pier under a tsunami bore

The Smoothed Particle Hydrodynamics (SPH) method is applied to investigate the impact of a tsunami bore on simplified bridge piers in this study. This work was motivated by observations of bridge damage during several recent tsunami events, and its aim is to further the understanding of the dynamic interaction between a tsunami bore and a bridge pier. This study is carried out by simulating a well-conducted physical experiment on a tsunami bore impingement on vertical columns with an SPH model, GPUSPH. The influences of bridge pier shape and orientation on free surface evolution and hydrodynamic loading are carefully examined. Furthermore, the unsteady flow field that is around and in the wake of the bridge pier is analyzed. Finally, GPUSPH is applied to explore the hydrodynamic force caused by the bridge pier blockage, the wave impact on structures, and the bed shear stress around a bridge pier due to a strong tsunami bore.