摘要: |
Precast (or portable) Concrete Barrier (PCB) is a guardrail system that is intended to contain and redirect a vehicle that has left the travel lane. Barrier connections are typically formed using steel wire or bar to form loops which are joined by a steel pin. While the materials used in connection systems are quite strong, exposure to the elements and winter maintenance chemicals can, over time, lead to corrosion and loss of effectiveness. The identification of such corrosion was a concern to the Montana Department of Transportation (MDT), which decided that additional research should be done on this issue to determine what, if any, past research has been done regarding PCB in general, PCB connection corrosion, the maintenance of barrier connection systems, and approaches to address corrosion on existing and future installations. The research would also identify approaches that may be taken in developing and implementing a transition plan for replacing PCB if needed. This report presents a synthesis of information from past published research and reports, as well as information from a survey of transportation agencies conducted as part of this project, regarding precast concrete barriers, the corrosion of their connection systems, approaches to rating/ranking this corrosion, and current state DOT practices for their maintenance and replacement. Potential strategies for prioritizing barrier replacement are identified and discussed. |