Title:
Straight Talk About Anchorage to Concrete-Part II
Author(s):
Robert W. Cannon
Publication:
Structural Journal
Volume:
92
Issue:
6
Appears on pages(s):
724-734
Keywords:
anchorage (structural); bolts; compressive strength; concretes;
embedment; expansion; failure; rock bolts; splitting tensile strength; studs.
DOI:
10.14359/9666
Date:
11/1/1995
Abstract:
Part I discussed the basic differences in philosophy contributing to confusion concerning the direction to be taken regarding code requirements for anchorage to concrete. It also discussed the effects of confinement and the initiation and propagation of cracking at the anchor head on the variation in pullout capacity of the concrete with embedment. Part I dealt primarily with U.S. test data for headed and undercut anchors. The two types of anchors were found to differ only with respect to edge capacities and minimum edge distances required to develop the full pullout capacity of the concrete. Part II examines test data from the author’s files on self drill expansion anchors and wedge bolts, as well as the accumulation of test data by ACI Committee 349 from both the U.S. and Europe involving the testing of headed anchors, undercut anchors, and various types of expansion anchors. Two of the most frequently used types of expansion anchors are examined first for differences with respect to pullout capacity of the concrete and with respect to Part I conclusions. The large compilation of test data are then examined to identify differences and to ascertain those factors contributing to the differences.