Elastomeric Concrete Plug Joints: A New Durable Bridge Expansion Joint Design

Expansion joints are important components of bridges that accommodate the movements between deck spans that result from thermal loads, traffic loads, and other environmental factors. Experience shows that joints undergo premature deterioration on a regular basis, which leads to unexpected problems caused by leakage of water and other corrosive chemicals over the components of the superstructure and substructure, which in turn leads to premature deterioration of those components. The Virginia Department of Transportation (DOT) has spent millions of dollars over more than 50 years for repair and replacement of joints. Several types of closed joints have been developed and installed in the past three decades to combat this problem. Jointless details at piers and abutments have also been developed and installed in the past three decades to eliminate the need for joints and the associated deterioration. However, the issue persists. The Virginia DOT’s Structure and Bridge Division has developed a new design for a flexible joint system with bonded and debonded zones. An elastomeric concrete material acts as the load-bearing surface as well as the component that allows free expansion and contraction. This joint system has been installed in selected pilot bridges on secondary roads for observation. The performance of this joint system and the challenges faced in its development are discussed.