Scour depth downstream sharp-crested weir

Abstract

Weirs are hydraulic obstructions constructed across an open-channel flow causing a rise in water which is useful to convert water to the channels upstream as well as using these structures as a measuring device. There are different types, and a sharp-crested weir is one of them. Local scour downstream hydraulic structures are one of the most critical problems affecting their safety and stability. Many studies conducted to prevent these facilities from collapsing, but the effect of adding a solid apron downstream weir still need deep studies. The current study included a survey of scour reduction downstream sharp-crested weir using a solid apron consisting of three different lengths, four different discharges, and sand bed material to calculate the maximum depth and length of scour hole when using an apron solid. The results proved that the depth and length of the scour hole are reduced to 19.3% and 27.7%, respectively, when an apron solid is used. Two empirical equations were found to determine the maximum depth and length of the hole with a coefficient of determination are 0.892 and 0.804, respectively.