Laboratory Investigation of Bridge Strip Seal Joint Termination Details
Strip seal termination turn-up at the barrier rail with a blockout
Turn-up specimen with blockout formed using blue insulation board
Straight-through terimation specimen using Watson Bowman Acme seal
Straight-through dogleg termination specimen using D.S. Brown seal
Start date: 05/01/14
End date: 02/28/16
- Laboratory Investigation of Bridge Strip Seal Joint Termination Details (4.97 mb pdf) February 2016
- Performance of Strip Seals in Iowa Bridges, Pilot Study (4.55 mb pdf) January 2001
- Laboratory Investigation of Bridge Strip Seal Joint Termination Details 938.92 kb pdf (Tech transfer summary) Feb 2016
- Laboratory Investigation of Bridge Strip Seal Joint Termination Details presentation slides (off site), Aug 2015
- Federal Highway Administration State Planning and Research Funding
- Iowa Department of Transportation
About the research
Bridge expansion joints, if not properly designed, constructed, and maintained, often lead to the deterioration of critical substructure elements. Strip seal expansion joints consisting of a steel extrusion and neoprene gland are one type of expansion joint and are commonly used by the Iowa Department of Transportation (DOT).
Strip seal expansion joints are susceptible to tears and pull outs that allow water, chlorides, and debris to infiltrate the joint, and subsequently the bearings below. One area of the strip seal that is particularly problematic is where it terminates at the interface between the deck and the barrier rail. The Iowa DOT has noted that the initial construction quality of the current strip seal termination detail is not satisfactory, nor ideal, and a need exists for re-evaluation and possibly re-design of this detail.
Desirable qualities of a strip seal termination detail provide a seal that is simple and fast to construct, facilitate quick gland removal and installation, and provide a reliable, durable barrier to prevent chloride-contaminated water from reaching the substructure.
To meet the objectives of this research project, several strip seal termination details were evaluated in the laboratory. Alternate termination details may not only function better than the current Iowa DOT standard, but are also less complicated to construct, facilitating better quality control. However, uncertainties still exist regarding the long-term effects of using straight-through details, with or without the dogleg, that could not be answered in the laboratory in the short time frame of the research project.