Behaviour of steel–precast composite girders with through-bolt shear connectors under static loading

Abstract

Accelerated bridge construction methods are being increasingly used to construct new bridges and replace existing ones. For the accelerated construction of steel–precast concrete composite bridges, a suitable shear connection detail is needed to develop composite action between the steel girders and the precast concrete deck panels. In this paper, a recent study is presented on the use of through-bolts to make this shear connection. Specifically, an experimental study is summarized, wherein static push tests have been performed on through-bolt connections with several parameters investigated including the bolt diameter, bolt pretension, and steel–concrete contact surface properties. While ultimate shear loads are achieved with through-bolts similar to those seen for conventional shear studs, the initial slip load is generally seen to be much lower than the ultimate load. A mechanistic model, capable of predicting the through-bolt connector ultimate capacity, is proposed and shown to give reliable predictions of the test results. Lastly, a finite element (FE) analysis study is presented, wherein the load–slip behaviour obtained from the push tests is incorporated in a model of a full-scale bridge girder and the effect of varying the bolt diameter and spacing on the girder behaviour is investigated.