Separated and combined effects of collar and sacrificial pile on scour reduction of bridge piers group

Document Type : Research Paper


University of Shiraz


Recognition and proposing some controlling methods to reduce destructive scour phenomenon is essential. In this study, the sacrificial piles, square collar and combination of sacrificial piles and square collar was used to control the scouring depth around the piers group. Two and three piers group along a line with a distance of 2.5D between the piers in longitudinal and transversal direction flow were investigated under clear water condition. The results showed that the effect of sacrificial piles in reducing the scour depth of the rear pier of pier groups in the flow direction is greater than single pier. The square collar was more effective in decreasing scour depth of front pier that equal to 72.22% and 69.23% in two and three piers group, respectively. The combination of sacrificial piles and square collar could further reduce the scouring depth. Also, in the two and three piers group in transverse direction of flow, the combination of sacrificial piles and square collar have shown more effective than square collar and sacrificial piles in decreasing the scour depth. The reduction of scour depth equal to 57.14% and 67.5%, for two and three piers groups respectively.


Main Subjects

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