SETTLEMENT OF BRIDGE APPROACHES (THE BUMP AT THE END OF THE BRIDGE)

This synthesis will be of interest to state Departments of Transportation (DOTs) geotechnical, structural, roadway design, construction, and maintenance engineers; DOT research staff; and personnel in local transportation agencies. This synthesis describes the current state of the practice for the design, construction, and maintenance of bridge approaches to reduce, eliminate, or compensate for settlement at the bridge/abutment/embankment interface or "the bump at the end of the bridge". It discusses the geotechnical and structural engineering design and procedural factors to reduce the bump at the end of the bridge, and includes numerous illustrations. This report of the Transportation Research Board presents data obtained from a review of the literature and a survey of the state DOTs. It is a supplemental update to Synthesis of Highway Practice 159: "Design and Construction of Bridge Approaches" (1990). The synthesis identifies and describes techniques that have been used to alleviate the problem of the bump at the end of the bridge including the location and cause of settlement and methods used to reduce settlement. In addition, the types of interaction between various divisions of the DOTs in the design, construction, and maintenance of bridge approaches are addressed.