Title:
Breakout Capacity of Anchors in Concrete
Part 1: Tension
Author(s):
Mansour Shirvani, Richard E. Klingner, and Herman L. Graves III
Publication:
Structural Journal
Volume:
101
Issue:
6
Appears on pages(s):
812-820
Keywords:
anchorage; breakout; concrete; tension
DOI:
10.14359/13456
Date:
11/1/2004
Abstract:
The overall objective of this paper is to evaluate four different procedures for predicting the concrete breakout capacity of tensile anchors under static and dynamic loading, and in uncracked and cracked concrete. An existing public-domain database of tensile anchors was evaluated and updated. Observed capacities of tensile anchors failing by concrete breakout were compared with the predictions of three methods: the 45-degree cone method; the concrete capacity (CC) method and a variation on it; and a theoretical method. Each predictive method was then evaluated using Monte Carlo analyses to predict the probability of failure by concrete breakout, using the design framework of ACI 349-90, Appendix B “Steel Embedments.” That framework was used because it was the reference of the U.S. Nuclear Regulatory Commission (U.S. NRC) at the time the research was conducted. Those methods were used because they were latest available in 1997 and 1998, when this research was conducted. Based on the results of this evaluation and on other information, procedures are proposed for designing tensile anchors. Many of those procedures have been adopted into current design provisions (ACI 318-02 and ACI 349-01); the recommendations are still pertinent to those current provisions.