Evaluating the performance of guardrail posts installed by driving through asphalt layers.

Details

• Creators:
  Scott, David ; White, Donald ; Stewart, Lauren ; Arson, Chloe ; Bakhtiary, Esmaeel ; Lee, Seo-Hun
• Corporate Creators:
  Georgia Institute of Technology. School of Civil and Environmental Engineering
• Corporate Contributors:
  United States. Federal Highway Administration
• Subject/TRT Terms:
  • Guardrails
  • Posts
  • Asphalt pavements
  • Installation
  • State of the practice
  • Finite element method
  • Evaluation
• Publication/ Report Number:
  FHWA-GA-15-1321
• Resource Type:
  Tech Report
• Geographical Coverage:
  Georgia
• Corporate Publisher:
  Georgia. Department of Transportation. Office of Research
• Abstract:
  The preferred procedure for guardrail installation in the State of Georgia includes a layer of asphalt (usually ; referred to as a “mow strip”) placed to retard vegetation growth around the guardrail. The objective of this multi-phase ; research program is to develop effective alternatives to post installation methods that incorporate a leave-out around the ; post. The work described in this report represents Phase I of the overall research effort. The research team evaluated ; the structural performance of guardrail posts installed in accordance with current GDOT (Georgia Department of ; Transportation) procedures that include an asphalt mow strip, as well as alternative installation options developed in ; conjunction with GDOT personnel. The current state of practice related to the use of asphalt vegetation barriers in the ; United States was identified through on a nationwide survey. An experimental program was carried out in accordance ; with applicable AASHTO guidelines. In parallel with the experimental program, a three dimensional finite element ; model was developed for a guardrail post installed through an asphalt layer. Results from the experimental program ; and finite element analyses were used to develop a series of quantitative criteria to evaluate the performance of the ; various post/mow strip configurations. Parametric studies were conducted on pertinent geometric variables in terms of ; the quantitative performance criteria. The results of this Phase I research program demonstrate that (1) there are ; potential combinations of mow strip thickness and rear distance that are likely to result in satisfactory dynamic ; performance, and (2) two techniques appear effective in reducing the ground-level restraint imparted by a mow strip on ; a guardrail system: decreasing the mow strip rear distance behind the post, and pre-cutting the mow strip in the region ; behind the post.
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• Format:
  PDF
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/29717/dot_29717_DS1.pdf
• File Type:
  [PDF - 12.92 MB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:7c5241e8f8ffa90621e615e1b38d279f8b3918769a7ee770a07b040aef0c34b6