Author(s): Alireza Masjedi; Hosein Kazemi; Elaheh Peymani Foroushani
Linked Author(s):
Keywords: Local scouring; Bridge pier; Bridge pier cape; Secondary flow
Abstract: Local scouring around the bridges pier is one of the most important causes of bridges demolition especially during the water floods. Scouring around the bridge piers in various position of river bend is among the most effective parameters in bridge designation. So for studying the scouring depth around the bridge pier in river bends, a series of experiments were set up in a Plexiglas laboratory flume with 180' bend and R/B=4.7 (R=Central radius of flume, B=Flume width). In this study, scouring phenomenon around the cylindrical pier in clean water condition were investigated by installing a cylindrical pier with 6 cm diameter in physical model of flume in the positions of 0,30,60,90,120,150 and 180 degree with flow discharge of 24,28,30 and 32 L/S and constant depth of 12 cm. Natural sand with uniform graining of D50=2mm and uniformity factor of 1.7 were used as bed materials. The results of this study show that, while cylindrical pier is placed in the bend, the maximum scouring depth is alternatively and maximum scouring occurs in position of 60 degrees. Also it was observed that in all positions, increasing the flow discharge increases the scouring depth.
Year: 2009