Jan Barnat
Brno University of Technolgoy, Czech Republic
Title: Experimental analysis of selected adhesives for bonded anchors
Biography
Biography: Jan Barnat
Abstract
The analysis presented in this paper deals with some selected problems of special use of bonded anchors. One of the problem is the limit of bond strength provided by the adhesive, which is important parameter especially for use in high performance concrete.
The tension resistance of bonded anchor can be limited by all materials used in anchoring system. When the steel anchor is installed in concrete of strength above 60 MPa together with common anchoring length, then the bond strength performed by the adhesive can be the most limiting factor of the anchor resistance. Therefore, it is necessary to study the real behavior of the thin layer of adhesive and find the way how to improve the adhesive characteristics.
The first part of the contribution discusses the design approaches used in codes for the bond failure type. The influence of concrete and adhesive performance is closely described in related references.
All experiments presented in this paper were focused on the bond strength value. In case, when the adhesive is the resistance limiting material in the system, then the bond strength can be defined only as an adhesive shear strength. Therefore when the main goal is to study adhesive characteristics. The concrete can be excluded from the analysis. The special steel specimen, which is effective for the testing of this shear strength, was designed. The design of this specimen is presented in this paper as well as the problem of the testing of adhesive itself.
Designed mixtures of high performance epoxy resins and vinyl ester resins are tested and the results are presented. The effect of additives as milled limestone and also milled FRP reinforcement are also analyzed.