TY - JOUR T1 - Effect of Position of Bridge pier on Scouring Depth in 180 Degree Rivers TT - اثر موقعیت پایه پل استوانه‌ای بر عمق آبشستگی در قوس 180 درجه رودخانه‌ها JF - JSTNAR JO - JSTNAR VL - 15 IS - 57 UR - http://jstnar.iut.ac.ir/article-1-1855-en.html Y1 - 2011 SP - 1 EP - 9 KW - Local scour KW - Bridge pier KW - 180 degree bend KW - Secondary flow KW - Clear-water scour. N2 - In this research, the effect of installing position of bridge pier on scouring depth was studied in a bend laboratory flume, which is made of Plexiglas with 180 bend and a relative radius of Rc/B=4.7. Tests were conducted using one pier 6 cm in diameter under four discharge conditions with constant depth of 12 cm and clear-water conditions. Flume bed was fully paved by uniform sand. It was found that maximum scouring depth occurred in bend when bridge pier was installed in the position of 60 degrees. Also, in all situations increased scouring depth occurred by increasing discharge. M3 ER -