Numerical Simulation of the over and through flow Discharge in Broad-Crested Gabion Weirs with side Slopes

Document Type : Research Article


1 School of Water Sciences Engineering, Shahid Chamran University of Ahvaz, Ahvaz, Iran

2 Department of Civil Engineering, Islamic Azad University-Estahban Branch, Fars, Iran


During the recent years, Gabion weirs have been taken into consideration due to their compatibility with the environment, positive effect on river’s water quality and their simple design and implementation. In this research, the hydraulic parameters of flow around broad crested gabion weirs (BCGW) with various side slopes are investigated. Overall, a number of 21 models comprising 7 various geometries each with 3 different porosities including (43%, 44%, 46%) and in different discharges were simulated and studied. Results indicated that the discharge coefficient (Cd), through flow discharge and energy dissipation increased by increasing the average diameter of particles. In addition, Increasing the area of the porous media by changing side angles from 0 to 60 reduces the discharge coefficient and through flow discharge. At final stage, experimental equations are presented using Nonlinear Multivariable regression analysis in order to calculate the discharge coefficient and through flow discharge of these structures.


Main Subjects

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