Kentucky, as most other states, has in the past relied on the AASHTO "Barrier Guide'' for guidance in the installation of guardrail. Additional information related to barrier selection and installation was recently published in the form of the AASHTO "Roadside Design Guide. " However, considerable judgement is required for application of this information and it was determined that significant benefit could be derived from development of guidelines representative of conditions in Kentucky. Listed below are significant results from this study.

  1. Results from a previous survey of guardrail standards and guidelines were summarized and it was found that only a few states suggested use of reduced guardrail standards.
  2. Warranting guidelines for clear zones and embankments based on Kentucky accident severities and costs were developed from a computer program included as part of the ''Roadside Design Guide. "
  3. For low service level roads, several operational barrier systems were recommended for consideration when the W-beam, blocked-out guardrail is found to be impractical due to geometric, terrain, or cost constraints.
  4. A procedure was developed to identify and prioritize highway sections in need of guardrail based on determining locations with critical numbers and rates of run-off-road accidents, conducting a field survey to tabulate hazard-index points, and performing a cost-effectiveness analysis.

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The contents of this report reflect the views of the authors who are responsible for the facts and accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the University of Kentucky, the Kentucky Transportation Cabinet, nor the Federal Highway Administration. This report does not constitute a standard, specification, or regulation. The inclusion of manufacturer names and tradenames are for identification purposes and are not to be considered as endorsements.