Reduction of Local Scour around Bridge Piers Using Different Countermeasures.(Dept.C)

Abstract

Local scour around bridge piers is one of the main causes of bridge failure. Experimental and hydraulic models were carried out to investigate three types of scour reduction methods around a single oblong pier, called slots, upstream curved face and sacrificial piles. First, these methods were used alone then combination of them was made to achieve the minimum scour depth. The results revealed that slots, in general, have more influence in reducing scour depth than upstream curved face, with a reduction in the scour depth of about 25% of maximum scour. On the other hand, the upstream curved face and straight slot together appeared to be the most effective in reducing the scour around the bridge oblong pier, with a percentage reduction equal to about 30%. When using two sacrificial piles with upstream curved face slotted oblong pier were used, the least scour amongst all the arrangement with about 49% reduction in maximum scour depth upstream of the pier was achieved.