Laboratory Testing, Field Installation, and Monitoring of a Silicone Foam Sealant for Bridge Expansion Joints

Abstract

Bridge expansion joint sealants are used to deter water and corrosive materials from leaking through the joint and damaging the bridge structure. However, problems with leakage from failing joint sealants have been observed. In response to this situation, a silicone foam sealant designed for small-movement bridge expansion joints was developed. The foam sealant proved to be easy to use and economical. In previously reported studies, various laboratory tests were conducted to evaluate the foam sealant’s tensile strength, compressive strength, reaction to various temperatures, stress relaxation, creep behavior, and bonding capabilities to various substrate materials, such as steel, asphalt, concrete, and polymer concrete. In the current study, further laboratory tests were conducted on the sealant. These tests included ponding and freeze-thaw resistance. The subject study included the development and use of an application procedure to install the silicone foam sealant into bridge expansion joints. After being applied to expansion joints on four bridges in the Northeast (Connecticut, New Hampshire, Rhode Island, and New York), continuous monitoring of the temperature, precipitation, and physical condition of the sealant was conducted for over 1 year. Based on these tests, it can be concluded that the silicone foam sealant is as easy to install and as durable as conventional solid sealants.