SPR 19-577: Evaluation and Update of Guardrail Rating Program

This Research Program for the period July 1, 2018 to June 30, 2020 is submitted in compliance with the provisions of Section 307 of Title 23, United States Code, and describes programs and operations for planning activities in the Kentucky Transportation Cabinet (KYTC) and the Kentucky Cooperative Transportation Research Program (KCTRP). This program modifies and updates such programs and is specifically intended to reflect the needs of the Kentucky Transportation Cabinet. It is fully expected that products from this program will also have national applications. The University of Kentucky Transportation Center is the main research group for the the Kentucky Transportation Cabinet. The SPR grant is the funding the is supplied each year for the many topics the Center is asked to research for KYTC The KCTRP is concerned with the development and conduct of a comprehensive research program in cooperation with the U.S. Department of Transportation, Federal Highway Administration (FHWA). In addition to research developed in cooperation with FHWA, the KCTRP may perform other services for the KYTC on a nonparticipating basis. The scope of these services could include activities such as research studies and special investigations of various engineering and operation activities. The Research Program and Implementation Advisory Committee (RPIAC), headed by the State Highway Engineer and coordinated through the Research Coordinator, will give direction to the research program. PROBLEM STATEMENT The KYTC's Division of Maintenance is responsible for managing identification and prioritization of roadway locations in need of guardrail. The current system in place for rating the need for guardrail installation ("Guardrail Rating Program") was updated in 2009 and crash/ accident data elements are not consistent with currently acceptable methodologies incorporated into the Highway Safety Manual (HSN[). Specifically, the "Accident Rate" element of the rating system, which is based on critical numbers of crashes and critical rate, should be replaced with the more statistically reliable "Potential for Crash Reduction" factor that can be determined based on HSM methodologies. In addition, the overall rating system should be reviewed to determine if the rating elements are appropriately weighted and if data input can be less dependent upon the experience of district personnel completing the rating forms. In some cases the level of experience and subjectivity of those inputting data has resulted in a degree of inconsistency in the overall process. OBJECTIVE Evaluate the KYTC's "Guardrail Rating Program" and recommend updates to improve the overall process and develop a more systematic means of analyzing all routes for guardrail needs to definitively identify those locations, which would benefit most from this type of safety improvement.