Evaluation of UHPC as a Repair Material for Corroded Steel Bridge Girders

Abstract

Corrosion damage of steel girder ends is a prevalent problem throughout the United States. This damage is often caused by leaking expansion joints, which deposit water and chlorides on the girders. Section loss at these critical locations can be detrimental to the bearing capacity of the girder. Current repair methods are costly, time consuming, and disruptive to traffic. A new repair method has been proposed by the University of Connecticut and the Connecticut Department of Transportation using ultra-high performance concrete (UHPC) to repair these corroded steel girder ends. The repair consists of welding headed shear studs to the undamaged portions of the web and encasing the girder in UHPC. The shear studs provide an alternate load path from the girder to the UHPC panels to bypass the corroded region. A series of full-scale 54-in. (1.37-m) deep plate girder specimens were tested to evaluate the load-carrying performance of the UHPC repair with different panel heights, stud layouts, and UHPC materials. The experimental program included a baseline corroded girder with no repair and three corroded girders repaired with UHPC. Conventional forming and casting techniques were used for each of the repairs in order to establish standard procedures that could be adopted for field implementation. One of the girders was exposed to simulated service-level vibrations during curing to demonstrate the ability to implement the repair without interrupting traffic. The results show that the UHPC repair presents a viable option for restoring the load bearing capacity of damaged girders with reduced plate thicknesses due to corrosion.