The research objective will be to determine the in-service performance of the NETC bridge railings and transition systems based on the percentage of fatal and serious injury crashes and barrier penetrations. The evaluation should examine all NETC bridge railing sites constructed in each cooperating state. Construction records and bridge inventories will be reviewed to develop an inventory of NETC bridge railings. Crash data for five years (and more if possible) will be collected for all NETC bridge railings identified in the inventory. Traffic data (e.g., posted speed limit, AADT and percent trucks) will also be collected, if available, for each inventoried NETC bridge rail. The crash, inventory and traffic data will be merged into a single database and the fatal and serious injury proportions will be calculated for each type of NETC railing by a variety of potentially confounding factors (e.g., posted speed limit, vehicle type, highway facility type, percent trucks, etc.). Similarly, the crash records will be examined for any indication of bridge railing penetration or rollover. This study should be conducted using the now available NCHRP 22-33 Guidance for the conduct of ISPEs. NCHRP 22-33 (Collaborative Approach to In-Service Performance Evaluations) has outlined an approach to the conduct of ISPEs which uses crash data to mimic the MASH evaluation criteria, thereby providing a direct comparison of actual field performance to the MASH evaluation criteria. Further, the NCHRP 22-33 Guidance was developed with the intent of collaborating across state lines to conduct more robust ISPEs just as is being proposed herein.
Technical Committee Members
- TC Chair, Jeff Folsom: Maine Department of Transportation
- David Kilpatrick, Connecticut Department of Transportation
- TBD, Massachusetts Department of Transportation
- Chelsea Noyes, New Hampshire Department of Transportation
- Chris Gagnon, Rhode Island Department of Transportation
- Chris Mooney, Vermont Agency of Transportation
AC Liaison: Dale Peabody, Maine Department of Transportation
Project Coordinator, Kirsten Seeber, CTC & Associates
MaineDOT is using these results to provide evidence that NETC rail performs well. MaineDOT changed their standard details to formally adopt MASH without crash testing because this study and the previous FEA modeling study show good performance.