Dam-Break Experiments on the Effect of Roughness Blocks in Open-Channels

Dam-break experiments simulate the sudden release of stored upstream water and its impact on a model. Since the stored water depth is the only adjustable parameter, it is difficult to control the flow velocity and inundation depth. In this study, roughness blocks were installed on the channel bed to regulate the flow, and the effects of their arrangement and height were examined. These blocks reduced the flow velocity, Froude number, and the drag forces on the model. The results revealed that the drag coefficients on the model depended on whether the dam-break flow overtopped or bypassed the roughness blocks.