A Study on Scour Failure at Bridge Foundation

Abstract

The success of a bridge relies on proper design and construction of its foundations. A Literature concerning water scouring at
bridge foundation and some cases of bridge failure were intensively reviewed. Two global cases and a local case of foundation failure
caused collapse of the bridge structure were selected for this study. The study was concentrated on Manshia Bridge in Khartoum. The
investigation involved field survey and laboratory testing on this project to examine the existing foundation conditions. The eastern
abutment investigated experienced sever failures in forms of excessive scouring and settlement in the embankment and the foundation
piles surrounded by water. The causes of these failures were found mainly linked to the high scouring rate of water lead to washout the soil from the embankment of the abutment and the foundation piles. The foundation design mistakes, poor construction, inadequate abutment protection and lack of maintenance were detected as the main cause of the bridge failure. To protect abutment against scouring problem, it is recommended to use rock protection for the embankment and river bed around the abutment.