Pull-Out Testing of Mechanical and Adhesive Anchors for High-Strength Concrete

Abstract

Experimental pull-out tests are conducted to evaluate the pull-out behavior of mechanical and adhesive post-installed concrete anchors embedded in high-strength concrete. The study compares measured pull-out capacities with code-based strength predictions in accordance with ACI 318 anchorage provisions. Anchors are installed in concrete blocks by drilling holes following manufacturers’ installation requirements. Mechanical anchors are installed using hammer-driven expansion, whereas adhesive anchors are installed by injecting epoxy into the drilled holes prior to anchor placement. Mechanical anchors are tested immediately after installation, while adhesive anchors are tested after a minimum epoxy curing period of 24 hours. Pull-out testing is performed using an M2008 heavy-duty tester. Concrete blocks measure 20 in × 20 in in plan and 8 in in thickness and are cast with a mix design achieving a compressive strength exceeding 8 ksi. Anchors are placed at corner, edge, and interior locations to investigate the influence of anchor location on pull-out capacity and failure mode. Experimental results are compared with pull-out strength predictions based on ACI 318 provisions using the 8-ksi concrete strength limitation. The results highlight the influence of concrete strength, anchor type, installation method, and edge distance on pull-out performance and provide insight into the applicability of current code-based design assumptions for post-installed anchors subjected to pull-out loading.