The local scour around bridge piers—a review of remedial techniques

ABSTRACT

The paper briefly describes the mechanics of local scour process around bridge pier and gives an in-depth review of the various techniques employed for local scour control and protection. The most common armoring device is placing of riprap stones around the pier. Despite the effectiveness of riprap armoring countermeasure, it faces some limitations such as cost ineffectiveness and susceptible to channel bed degradation. The performance of various flow-altering devices is studied. The combination of slot and collar plate can be a suitable solution to prevent the local scour if well designed and constructed properly. The combination of permeable sheet piles with riprap can even reduce the scour depth effectively up to 91% in live bed scour conditions. The combination of vanes and collar plate around oblong bridge pier results into less extent of scour and produces a higher degree performance potential of 86.36% as compared with unprotected oblong pier. Although the composite device has higher scour reduction potential than individual device, there is no guarantee that there will be complete elimination of local scour. Therefore, more research is needed to analyze the stability of this device on the prototype and field application and enhance their efficacy furthermore.

KEYWORDS:

• Local scour
• armoring devices
• flow-altering devices
• riprap
• collar plate
• sacrificial piles

Disclosure statement

No potential conflict of interest was reported by the authors.