摘要: |
Precast concrete bridge rail systems offer several advantages over traditional cast-in-place rail designs, including reduced construction time and costs, installation in a wide range of environmental conditions, easier maintenance and repair, improved railing quality, and greater flexibility for aesthetic treatments. The objective of this project was to develop a precast concrete bridge rail system that met the TL-4 impact safety standards provided in MASH. The design criteria for the new bridge rail system included criteria for barrier geometry, provisions for open and closed rail options, constructability, weight limitations, segment length, design impact loads, connection of barrier segments, and connection to the bridge deck among other factors. The research effort proceeded in several phases. First, the research focused on determining the overall concept for the new bridge rail system in terms of the rail configuration and geometry as well as the required barrier reinforcement. Next, design concepts for the joints connecting adjacent rail segments were designed and subjected to dynamic component testing in order to select a design capable of meeting design criteria for the precast bridge rail system. After selection of an appropriate rail joint, the researchers developed connection details for the attachment of the rail to the bridge deck. |