Abstract:
The objective of the study is to investigate by experiment of the characteristics of flow through thestepped gabion spillways. The width of the stepped gabion spillways is 0.40 m and the slopes of thestepped gabion spillways are 30?, 45?, and 60? with total drop height 1.50, 2.12, and 2.60 m,respectively. The step height is 5 percent of the total drop height. The discharge through the steppedgabion spillways varying from 4 to 68 l/s. Base on dimensional analysis, the importants parametersare analyzed and the relevant dimensionless parameter are formed. It was found that the energy offlow was more dissipated in the stepped gabions spillways than in the plain stepped spillways about10 percent. The energy loss was influenced by the spillways drop number, the slope of thespillways, and the size of the filled stone. At the same spillways drop number, the energy loss in themilder slope was greater than that of the steeper one. As the energy loss of flow increased, thevelocity of flow decreased. The velocity of flow at the outlet of the stepped gabion spillways wasless than that of the plain stepped spillways about 14 percent. In addition, it was found that flowpressure acting on the step face could be reduced by the filled stones in the gabion boxes by about27 percent from these occurred on the plain stepped spillways of the same dimensions.