Optimized Pre-Tensioning and Re-Tightening Approaches for Anchor Rods for Highway Signs, Luminaires, and Traffic Signals (SLTS)

Previous studies and field investigations have demonstrated that anchor rods at the base of structural posts for Highway Signs, Luminaires, and Traffic Signals (SLTS) are susceptible to relaxation. This results in loosening of base connections and premature failure of such structural supports. On the other hand, re-tightening of anchor rods 48 hours after the installation requires significant resources, manpower, and additional costs. This implementation project aims to review past studies, systematically study the pre-tensioning methods and re-tightening procedures through experimental testing to fill the knowledge gap, and to propose an optimized method for pre-tensioning and re-tightening of anchor rod connections to result in acceptable relaxation, while minimizing the resources for doing so, and minimizing chances of over-tightening. In the end, the proposed methodology will be implemented in two local structural supports for SLTS in the state of Minnesota to evaluate the effectiveness of the proposed methodology.

• Record URL:
  • https://researchprojects.dot.state.mn.us/projectpages/details?id=30593&type=CONTRACT

Language

• English

Project

• Status: Active
• Funding: $197,579.00
• Contract Numbers:

  1058722

• Sponsor Organizations:

  Minnesota Department of Transportation

  395 John Ireland Boulevard
  St Paul, MN  United States  55155
• Managing Organizations:

  Minnesota Department of Transportation

  Office of Research & Innovation
  395 John Ireland Boulevard, MS 330
  St. Paul, MN  United States  55155-1899
• Performing Organizations:

  University of Minnesota

  Department of Civil, Environmental and Geo-Engineering
  Minneapolis, MN  United States  55455
• Principal Investigators:

  Mortazavi, Pedram

• Start Date: 20250401
• Expected Completion Date: 20270531
• Actual Completion Date: 0

Subject/Index Terms

• TRT Terms: Luminaires; Optimization; Posts; Pretensioning; Rods; Structural supports; Traffic signals; Traffic signs
• Geographic Terms: Minnesota
• Subject Areas: Bridges and other structures; Construction; Highways; Maintenance and Preservation;

Filing Info

• Accession Number: 01950510
• Record Type: Research project
• Source Agency: Minnesota Department of Transportation
• Contract Numbers: 1058722
• Files: RIP, STATEDOT
• Created Date: Apr 1 2025 4:33PM