Enhancing bridge pier resilience against scouring during extreme flood condition using vegetation as a countermeasure-experimental approach

In the current investigation, scour mitigation around the bridge pier has been explored using vegetation of different densities (G/d) and aspect ratios (A/R) under various flow conditions. Initially, scour depth around the bridge pier was measured without vegetation elements, and afterwards vegetation elements were installed on the upstream side of the bridge pier to investigate maximum scour reduction. The result demonstrates that denser vegetation elements with a lower A/R value reduce scour depth significantly because of greater resistance to the flow. However, scour depth decreased by decreasing the G/d and A/R values from 2.85 to 0.71 and 18.5 to 7.45, respectively. A maximum scour reduction of 71.7% was observed by placing denser vegetation with A/R = 7.46 on the upstream side of the pier. The findings of the present research help to provide an eco-friendly solution for bridge pier scour mitigation.