Title: Stress Versus Time-To-Failure Test Method for Evaluating the Sustained Load Performance of Adhesive Anchor Systems in Concrete

Author(s): Todd M. Davis and Ronald A. Cook

Publication: Symposium Paper

Volume: 283

Issue:

Appears on pages(s): 1-12

Keywords: Adhesive anchors, creep, stress versus time-to-failure, sustained load testing.

DOI: 10.14359/51683764

Date: 3/1/2012

Abstract:
ASTM E488 and ASTM E1512 as well as ICC-ES AC308 and ACI 355.4 have extensive testing protocols for the short-term and long-term evaluation of adhesive anchor systems. Currently the sustained load testing procedures establish residual load and displacement criteria on projected displacements from a 1000 hour sustained load test. An anchor is considered approved for sustained load if it meets these pass/fail criteria. In an NCHRP research project conducted at the University of Florida, an AASHTO standard (AASHTO TP 84-10) was developed to evaluate the sustained load performance of adhesive anchor systems based on a stress versus time-to-failure approach common with many testing protocols. Adhesive anchors are loaded to failure at various percentages of the mean static load as determined from static load tests. The resulting stress versus time-to-failure relationship generated from this test method is very useful to an engineer designing with adhesive anchors under sustained load. A subsequent NCHRP research project conducted in partnership at the University of Florida and the University of Stuttgart will utilize this test method to evaluate the long-term performance of adhesive anchor systems under sustained load coupled with various installation and in-service conditions (temperature, moisture, etc).