Long-Term Performance of Epoxy Adhesive Anchor Systems

Adhesive anchor systems are used to anchor both threaded rods and reinforcing bars into hardened concrete. Common transportation structure applications for adhesive anchor systems include bridge widening, structure-mounted signs and appurtenances, luminaires and light poles, concrete repair and rehabilitation, barrier retrofitting, utility installation on existing structures, and tunneling finishing. The objective of National Cooperative Highway Research Project 4-37, “Long-Term Performance of Epoxy Adhesive Anchor Systems,” was to develop proposed standard test methods, materials specifications, design specifications and guidelines, construction specifications and guidelines, and quality assurance guidelines for the use of adhesive anchor systems in transportation structure applications. Development of these standards was founded on the results of a comprehensive program of laboratory experiments to determine, predict, and verify the long-term performance of adhesive anchors under sustained load in their typical service applications and environments. The research investigated the effects of various parameters on the long-term bond strength of adhesive anchors in hardened concrete. Testing was conducted on three adhesives of different chemistries that had passed current product evaluation criteria requiring sustained load testing at 110°F. A stress versus time-to-failure approach was used to evaluate the effects of various parameters on the sustained load performance of adhesive anchors. Within the range of parameters studied, only elevated service temperature (>120°F) and manufacturer’s minimum cure time were shown to influence the sustained load performance beyond that predicted by short-term tests of fully cured adhesive. Rheological analysis of the adhesives alone was conducted to investigate any correlation with anchor testing in concrete, but no consistent relationships were discovered that applied to all three adhesives investigated. Additionally the effect of early-age concrete on the bond strength of adhesive anchors was investigated. This report, along with thirteen appendixes printed here and seven appendixes available to download from the NCHRP Project 04-37 web page at http://apps.trb.org/cmsfeed/TRBNetProjectDisplay.asp?ProjectID=2495, fully document the research.

Language

  • English

Media Info

  • Media Type: Print
  • Features: Appendices; Figures; Photos; References; Tables;
  • Pagination: 277p
  • Serial:
    • NCHRP Report
    • Issue Number: 757
    • Publisher: Transportation Research Board
    • ISSN: 0077-5614

Subject/Index Terms

Filing Info

  • Accession Number: 01500254
  • Record Type: Publication
  • ISBN: 9780309283571
  • Report/Paper Numbers: Project 04-37
  • Files: TRIS, TRB, ATRI
  • Created Date: Nov 27 2013 2:30PM