Experimental Study: Effects of Pier Position and Critical Velocity Ratio on Scour Pattern in Two Consecutive Bends Under Clear Water Condition

This study investigated scour and sedimentation processes around a cylindrical bridge pier in two consecutive channel bends. These tests were conducted for different positions of the piers on the path and for different critical velocity ratios (U/Uc). Therefore, the scour variations were investigated for piers installed at eight different positions of the two consecutive channel bends for three different cases of U/Uc (0.9, 0.95, and 0.98). The results indicated that as the piers were fixed at the subsequent positions of the upstream bend, the scour depth arose in the vicinity of the piers; installation of the pier at the 0° angle resulted in the minimum scour depth and its position at 90 and 135° angles bred the greatest scour depth. In addition, from the beginning to the middle of the downstream bend, this trend continued to rise, so a 45