Bridges and elevated sections of highway have to perform in extreme conditions. Handling changing weather conditions and high traffic loads means fixed and expansion joints need to allow for structure fluctuations, while being sealed to protect structure integrity.
Most bridges built after the late 1960s use preformed rubber compression to seal joints, which typically begin to fail after only a few years. This leads to water leaks and accumulation of de-icing salts and debris, which can rust or corrode the substructure components, columns and piers of a bridge or elevated roadway.
Replacing these seals can be an expensive and laborious process, especially when the likelihood that the new seals will fail again and require another replacement is considered.
The Colorado Department of Transportation (CDOT) was looking for a better solution when it needed to reseal the joints along I-70 in Glenwood Canyon. It wanted a cost-effective, easy installation that would prevent water from entering the joint and not require long road closure times.
Dow Corning and SSI Joint System Provides SolutionCDOT turned to Silicone Specialties, Inc. (SSI), a nosing material manufacturer and Dow Corning Sealant Distributor, and Dow Corning to learn more about the benefits of the X.J.S.® Expansion Joint System, which combines the tough, wear-resistance of SSI’s Silspec® 900 Polymer Nosing System (PNS) with the rapid-curing, high-movement capability of Dow Corning® 902 RCS Joint Sealant.
“There was a rubber seal in place when we began the project,” said Joe Kelly of G.A. Western Construction. “We removed the rubber, replaced it with an epoxy and then applied the X.J.S. system to the two-inch expansion joint. So far the project has done an excellent job of solving CDOT’s perennial problem with faulty two-inch joints.”
The X.J.S. system enhances joint performance without complicated installation or extensive road closures. “The X.J.S. system has provided a relatively simple solution for joint replacement and repair,” said Delmon French of the Colorado Department of Transportation. Road closures are a particular concern in remote areas, like Glenwood Canyon, where alternate routes are not available.
“We worked closely with CDOT’s bridge engineers to find ways to complete needed repairs with minimal impact on the traveling public,” noted Dale Baker of SSI Highway Products Sales. “The X.J.S. Joint System gave CDOT a flexible solution in terms of joint configuration and traffic accommodation when repairing bridge expansion joints in Glenwood Canyon.”
The X.J.S. system has been in use since the early 1990s throughout the United States in a wide variety of climates and configurations, proving their versatility. “Some of the joints are up to five years old and as of January 2008 have performed well in the harsh conditions experienced on this stretch of I-70,” reported CDOT’s French.
The product has been used successfully by DOTs and transportations authorities throughout the United States.
“We will definitely be working with the product on current and future projects,” said Kelly of G.A. Western Construction.
For more information about these and other Dow Corning materials for the construction industry, or for the name of the Dow Corning representative in your area, call toll-free 1-877-SEALANT (1-877-732-5268). Or visit our construction web site at www.dowcorning.com/construction.