01365737

Component

State Departments of Transportation are responsible for evaluating bridges over waterways for scour and stream stability to protect the traveling public. While stream stability is often considered as being independent of scour, they typically occur simultaneously. The Burr's Ferry Bridge over the Sabine River represents a case study where stream stability and scour occurred simultaneously, and led to extreme scour around Pier 3 that needed to be repaired immediately. The Burr's Ferry Bridge is located on Texas Highway 63 (TX 63) and Louisiana Highway 8 (LA 8), and spans across the Sabine River downstream of Toledo Bend dam and reservoir. The Burr's Ferry Bridge was constructed prior to the Toledo Bend dam being constructed and is located in a bend in the river. Prior to the dam being constructed the Sabine River migrated some during high flow events. However, after construction of the dam the river has undergone a series of dramatic migration shifts in the vicinity of the bridge which has caused extensive erosion and a change in flow direction. The changes in the vicinity of the bridge have exposed a pier that was previously protected, which led to extensive scour. The pier is founded on a spread footing supported by fine sand. During the most recent flooding scour occurred that created a water filled hole that extended down to and below the footing at certain locations. This caused great concern for the stability of the bridge and the traveling public, so immediate action was taken to place to determine repair measures so an emergency contract could be let. The repair measures taken were to use jet grouting to support and confine the footing, with a cap of lean concrete being used to deter future scour. This paper presents the background information, documentation of the scour, and details the repair measures.

This paper was sponsored by TRB committee AFP10 Engineering Geology

01362476

12-2230

English

15p

2012

Transportation Research Board 91st Annual Meeting

Digital/other

Figures; Maps; Photos; References; Tables

Bioremediation; Bridges; Case studies; Environmental impacts; Scour; Streambeds

Texas

Bridges and other structures; Environment; Highways; Maintenance and Preservation; I15: Environment; I24: Design of Bridges and Retaining Walls; I60: Maintenance

Transportation Research Board Annual Meeting 2012 Paper #12-2230

TRIS, TRB

Feb 8 2012 5:08PM