A state-of-the-art, flexible, easy-to-replace plug-type expansion joint for the Delaware Memorial Bridge

Abstract

The modern flexible plug expansion joint, which uses a special polyurethane material rather than the asphaltic material traditionally used, has been developed to offer an optimal small-movement expansion joint solution, in many cases, to bridge construction and maintenance engineers. Its long- term performance is vastly superior to that of the asphaltic plug joint – thanks, for example, to its great strength and elasticity (with the material allowing 650% elongation before failure), its resistance to both very low and very high temperatures, and the special advantages it offers when used to replace old joints in existing structures with minimum impact on traffic. The expansion joint is described, in terms of properties, benefits and installation, with reference to an ongoing project to replace the expansion joints of the Delaware Memorial Bridge.