Dam-Break Surges with Floating Debris

Abstract

The effect of floating debris on dam-break surges is studied experimentally. Hexahedron plastic particles having a specific gravity of 0.92 are used as debris. In addition to qualitative investigation of the surge behavior, the speed and height of the surges are plotted for various downstream to upstream depth ratios and debris concentration. The results are compared with the clear-water surges. Deceleration and the increase in height of the surge are more pronounced for smaller initial depths downstream of the gate. In general, the speed of the surge is found to be a function of downstream to upstream depth ratio, the ratio of the mass of the debris per unit surface area to the mass of the water per unit surface area upstream of the gate, and the particle size relative to the upstream depth. The wave height, on the other hand, is found to be a function of the depth and concentration ratios for smaller initial downstream depths. For higher initial downstream depths, the wave height is a function of the depth ratio only.