Fastening elements in concrete structures - numerical simulations

Abstract

Anchoring elements such as headed and expansion studs and grouted or undercut anchors, are often used for local transfer of loads into concrete members. In order to better understand the failure mechanism, a large number of experiments have been carried out in the past. However, due to the complicated three-dimensional load transfer a very few or no numerical studies have been performed for a number of different fastening situations i.e. influence of the embedment depth, crack-width inftuence (fastening in cracked concrete), influence of the edge distance etc. Therefore, in the present study some results of the axisymmetric and three-dimensional numerical analysis of the headed studs embedded in plane concrete block are presented. Influence of different geometrical and material parameters have been studied employing finite element method and nonlocal microplane model. Comparison between experimental and numerical results indicate reasonable good agreement. Generally it has been observed that the failure mechanism is governed by fracture energy rather than by tensile strength of concrete. As a consequence, the size effect is strong and close to linear elastic fracture mechanics.