Experimental investigations on concrete cone failure of rectangular and non-rectangular anchor groups

Abstract

The current recommendations given in the codes and guidelines for design of anchorages to concrete are limited in scope to rectangular and regular anchor groups with a maximum of three anchors in a row. Furthermore, several assumptions are made, which may render the designs conservative but may also lead to unconservative results such as the required base plate thickness and the cracked concrete assumption. The aim of this experimental study was to investigate the load-displacement behaviour of tension loaded anchor group configurations that are either only partly covered or not covered by the current design provisions. Furthermore, this work aimed to generate an experimental database on the concrete cone failure of anchor groups under tension loading. The results of a comprehensive experimental program carried out on diverse anchor group configurations within and beyond the scope of the European Standard EN1992-4 are discussed focusing on several aspects such as (i) different geometric configurations, (ii) varying stiffness of the base plate, and (iii) influence of eccentricity. The experimental program contains tests on single anchors and on anchor groups in normal- and high-strength concrete. The testing concept, test setup and the test results are discussed in detail in this paper. Based on the evaluation of the test results presented here, a new analytical model is being developed for the concrete cone failure mode of tension loaded anchor groups that will be presented in a future paper.