This paper describes the development of the Washington State Department of Transportation's (WSDOT) bridgerail retrofit program. Prior to 1984, other than a program to upgrade low-base aluminium rails, the department's informal policy on replacing substandard bridgerails was to incorporate a replacement in a highway construction project to obtain a desired roadway width mandated by accident history. Otherwise, bridgerails were exempted from a project even if the approach rails were upgraded. As a result of this new retrofit policy, substandard bridgerails are being upgraded systematically, on an individual project basis, as part of WSDOT's resurfacing, restoration, and rehabilitation (3r) program. The retrofit program was developed to provide a uniform policy for upgrading substandard bridgerails. This policy is used in conjunction with our past practice of replacing substandard bridgerails with a concrete new jersey shaped barrier. Bridgerails addressed in the development of this program included open concrete baluster, steel post rails, and wooden rails. Systems considered for the retrofit program included w-beam, 12-gauge thrie beam, and 10-gauge thrie beam. In conjunction with this program, it was also important to develop appropriate approach rails and transition sections for these systems. The application of this bridgerail retrofit policy has proven to be of real value to the state of washington. It provides a low-cost solution to retrofitting bridgerailing.
Abstract