Experimental Study on Erosion of Opposing Bank at the Confluence of a Culvert and a Channel

This research provides an analysis of the erosion of channel banks opposing a point flow. The confluence of channels is common in hydraulic facilities; however, little research exists on quantifying the erosion. In practical cases, protection of the opposite bank in front of a culvert is designed solely based on engineers’ prior experience and judgment, due to the lack of a standard procedure. Due to the lack of established guidelines, a higher possibility of an over/underestimated design can occur. In order to study the effects of geometry and flow conditions on erosion, a stream table is utilized with scaling of the culvert and channels. To simulate the fluvial streams, a material made from recycled plastic or sandy soils is used. By running experiments with different flow rates and channel geometries, such as Froude number, angle of flow, discharge ratio, and culvert size, we can observe how the point flow of a culvert will affect the erosion of opposing banks. Data collected from these experiments will be used to develop empirical equations to quantify the erosion of channel banks for different flows and culvert geometries. The outcomes of this ongoing research will serve as guidelines for designing bank protection measures in front of culverts, in addition to providing a scaling methodology for future research endeavors related to erosion and sediment transport in the confluence of streams.