Experimental Investigation of the Energy Dissipation and the Downstream Relative Depth of Pool in the Sloped Gabion Drop and the Sloped simple Drop

The present study investigated the characteristics of hydraulic parameters of Sloped Gabion Drops and Simple Drops. Therefore, 120 different experiments were performed on both types of sloped gabion drop and sloped simple drop with three angles and two heights. Results showed that by increasing the relative critical depth in both tested models, causes a reduction in relative energy dissipation rate but an increase in relative downstream depth. Comparing the results for sloped gabion drops and sloped simple drops showed that the use of gabion structures with three angles and two heights which, have been investigated, increases the average energy dissipation efficiency 561% and the average downstream relative depth 50.1% compared to the simple drops. So, this results in a decrease in the erosion of the downstream bed of the structure and the length of the pool. The results showed that as the angle of incline increases, the average energy dissipation efficiency decreases and, the average downstream relative depth increases. The results showed that the change in the angle of the incline in sloped gabion drops had a relatively small effect, in comparison with the simple drops due to the physical properties and the complex hydraulic effects of the flow through the porous structure. Also, some relationships were presented to estimate the relative energy dissipation rate and the downstream relative depth rate in the sloped gabion drops by using 80% percent of laboratory data, and the rest 20% of the data were used to test the relationships with the evaluation criteria.