Derivation of the bondslip characteristics for FRP plated steel members

In order to understand the behaviour of steel members retrofitted using adhesively bonded fibre
reinforced polymer (FRP) plates, the bondslip characteristics of the adhesive joint between the FRP and
steel must first be established. This is important so that debonding does not occur whilst the members
are in service. Previously, purely empirical research on establishing the bondslip characteristics involved
strain gauging the length of the FRP plate, which can lead to a major scatter of results as well as
underestimating the peak shear stress. The subject of this paper is to describe a technique for quantifying
the bondslip characteristics based on a structural mechanics approach and which does not require strain
gauging the plate. Two types of pull tests and a partial-interaction numerical model are used to quantify
the major characteristics of the bondslip and two types of adhesive are used to illustrate the approach.