Comparison of permeable Groynes with triangular and linear arrangement in bridge abutment scour control

Bridges are important for establishing communication routes, and every year many bridges are destroyed due to scouring around the support. Spur dike are hydraulic structures that reduce scouring by diverting streamlines from structures. In this paper, a triangular arrangement for permeable spur dikes is proposed, and its performance with linear spur dikes in controlling the scouring of the abutment is numerically investigated and compared. To make a correct comparison, the permeability ratio and the distance of both triangular and linear arrangements were assumed to be the same. The results show that the linear arrangement of three series of two columns performs better than the similar triangular arrangement, and the linear arrangement of four and five series of two columns performs worse than the similar triangular arrangement. Also, among all the models, the triangular arrangement equivalent to two series of five is the most optimal. It reduces scour depth by 46% compared to the control case (Abutment without protective spur dike).