EFFECTS OF RESERVOIR BOTTOM SEDIMENTS ON HYDRODYNAMIC PRESSURE OF GRAVITY DAMS

Based on P-wave propagation theory, the boundary condition at the surf ace of the sediment is derived and the different boundary conditions a t the bottom of a reservoir are given as a unified form in this paper. With different boundary conditions at a reservoir bottom, a rigid gra vity dam has been analysed. From the results, it can be concluded that effects of the reservoir bottom sediment on the hydrodynamic response of gravity dams can be mainly attributed to the following two aspects : the amplification effect to enlarge the motion on the water-sediment interface and the damping effect to reduce the response of the system . It is a consideration of the amplification effect of the sediment on incident waves that makes this study very different from the previous studies on the hydrodynamic response of gravity dams.