A Plate Type Edge-Lift Anchor: Influence of Reinforcing Configurations on Failure Loads

Abstract

AS3850 Tilt-up Concrete Construction [1] is the current standard for design of lifting anchors and bracing in Australia. However, this standard does not provide a recommendation for calculating the capacity of edge-lifting anchors (normally placed in the edge of thin wall elements) which are commonly used in the precast industry throughout Australia. These anchors may experience a load under tension or combined tension and shear during the lifting process. The American Concrete Institute (ACI)318-08 Building Code Requirements for Structural Concrete [2], the Precast Concrete Institute (PCI) Design Handbook – Precast and Prestressed Concrete [3], and ComitéEuro-International Du Béton(CEB)Design of Fastenings in Concrete [4] include provisions for general anchorage configurations (such as multiple face lift anchors) rather than what are typically seen in edgelifting anchors. Not only are anchor configurations for edge lifting anchors different from those described in these standards, but the reinforcement around the anchor can vary significantly to those denoted in standards.This paper is an evaluation of pull out test data for edge lift anchors in thin walled elements. Using the formula in the ACI 318-08 [2], developed predominantly for footed anchors, comparisons of the predicted capacity and the test pull out capacity of the edge lift anchors is made. Data is presented on 154 tests; the variables tested include concrete compressive strength at time of testing and the provision and arrangement of reinforcement. In addition to the edge lift anchors, 90 face lift footed anchors were also tested and some of the more relevant data is presented for these tests.