DFI Journal: Vol III: 2 Issues (No. 1 May 2009 and No. 2 Nov 2009), (DFI)
Reduction of Local Scour around Cylindrical Bridge Piers Using Upstream Protective Piles (Vol. 3 No. 1)
Dr. A. K. Bhattacharya; Dr. S. Basack
Cylindrical bridge piers are widely used and equations exist that can predict the maximum depth of local scour around such piers. Scour around piers is an undesirable phenomenon, as it requires the foundation to be placed to a greater depth resulting in increased cost, making it worthwhile to investigate scour-reducing measures. A number of scour-reducing measures have been tried out for cylindrical bridge piers including placing a concrete collar around the pier, having a delta-wing projecting upstream in front of the pier, placing riprap around the pier, using a group of piers instead of a single pier, having a slot in the pier aligned in the longitudinal direction. The objective of this study is to investigate the effect of upstream protective piles on reduction of maximum local scour depth around a cylindrical bridge pier. The upstream piles are placed at different radial distances in front of the pier and the scour depths are observed. The proposed equation of Dey (1997) for determining the maximum depth of scour around a cylindrical bridge pier is used. The reduction of local scour around the pier is compared with local scour around an unprotected pier.
|article #1665; publication #1002 (DFIJ-III)|