Title: Investigation of Pull-Through and Pullout Failure Modes of Torque-Controlled Expansion Anchors
Author(s): Zhao Chen, Somayeh Nassiri, Anthony Lamanna, and William Cofer
Publication: Structural Journal
Appears on pages(s): 17-27
Keywords: empirical model; expansion anchors; finite element model; pullout; pull-through
Torque-controlled expansion (TCE) anchors are common concrete anchors that commonly fail in pull-through (PT) and pullout (PO) modes when installed in deep effective embedment depths. While concrete breakout failure has been adequately researched, no design equation is available to predict the ultimate tensile strength in these failures (Np). To investigate the PT and PO failure modes, 128 tension tests on TCE anchors from three manufacturers in three diameters were tested in two effective embedment depths per diameter. Also, these tests were simulated by finite element models (FEMs) using ABAQUS. The FEMs accurately identified different failure modes, and the predicted strength agreed well with the Np test results. Additional FEM results were obtained by a parametric study, which showed that anchor diameter, effective embedment depth, concrete strength, and cone geometry are significant to Np results. An empirical prediction model for Np was developed. The model was validated by the test results.