Wedge splitting test for a steel–concrete interface

This paper presents a test method designated for the determination of the stress–crack opening relationship of a steel–concrete interface. The method is based on the well known wedge splitting test (WST), and it is illustrated how to obtain the stress–crack opening relationship through an inverse analysis. This inversion method utilizes the cracked hinge model, modified such that it describes the problem at hand. In this paper, pure concrete and steel–concrete composite specimens are tested and compared. It turns out that interfacial cracking of a bimaterial specimen usually behaves as one of the parent materials, in this case concrete. The stress–crack opening relationship of both the concrete and bimaterial specimens are obtained through the proposed inverse analysis. The results show, that interfacial cracking is dominated by the so-called wall-effect and its behavior can be described as quasi-brittle. However, due to the wall-effect, interfacial cracking is more brittle than for the pure concrete.