Investigation of Scour Reduction at Downstream Side Flushing Causeway – An Experimental Approach

Abstract

Listen

Translate article

Scouring poses a significant threat to the causeway, potentially resulting in its damage or complete failure. The force of fast-moving water acts upon the foundation, sweeping away sediment that otherwise stabilizes the causeway. In the current investigation, scour at downstream side of flushing causeway (with no vent) under four different conditions and glass sided open channel. A wooden model of causeway with different elevation above sand bed (D50) was placed for different four conditions. A total of 36 cases were performed in the laboratory to investigate scour. The result shows that scours at the downstream side of the causeway increase with increase in the Froude number (0.16–33). The maximum scour was observed at causeway elevation of 6cm above sand bed and Froude number 0.33. It was observed that scour at the downstream side of causeway reduced by providing riprap and vegetation as a countermeasure. Scour depth at the downstream side of the causeway reduced up to 40% for 6cm elevation of causeway above bed level and 25% for 6cm elevation of causeway above bed level when vegetation was used as a countermeasure. It was concluded that countermeasures such as riprap, and vegetation reduced scour depth at the downstream side causeway up to significance level.