A GEOTECHNICAL PERSPECTIVE: DESIGN AND CONSTRUCTION OF HIGHWAY BRIDGE FOUNDATIONS FOR SCOUR

Scour of foundation soil and rock is the most common cause of bridge failures. To address this problem, the American Association of State Highway and Transportation Officials and the Federal Highway Administration developed and implemented comprehensive and stringent design guidelines and codes during the late 1980s and early 1990s. Although scour related losses have been significantly reduced as a result of their implementation, significant concurrent increases in foundation costs and construction difficulty have occurred as well. This paper examines the causes of scour related escalation in foundation costs and constructability difficulties from a geotechnical perspective. The focus will be on: (a) key considerations within the current scour design and construction processes; (b) application of scour codes and guidelines; (c) gaps in processes and guidelines; and (d) scour research priorities.