Scale modeling of the Bouzina Dam flood mitigation structures

Abstract

The design of the RCC (roller-compacted concrete) Bouzina Dam (Batna Province, Algeria) was verified using a scale model. The length scale of the physical model was 1:40 and the hydraulic parameters were scaled applying the Froude similarity. The tests focused on a standard Creager profiled spillway crest (with five bays), a converging stepped chute and a stilling basin. The main design problem was selecting the optimal shape of the stepped chute side walls. The converging chute generated standing waves, resulting in a significant flow depth increase in the vicinity of the walls. The optimal shape of the side walls was selected through a trial-and-error procedure, ensuring the most favorable flow conditions. Improving the flow conditions in the chute resulted in better flow conditions inside the stilling basin as well, so that the initially proposed energy-dissipation baffle blocks could be removed. Measurements of hydraulic parameters (water levels, depths, velocities, pressures) on the scale model verified the proposed improvements (compared to the original design).