Shear behaviour of in-situ concrete stitches of precast concrete segmental bridges

Abstract

The in-situ concrete stitches of a precast concrete segmental bridge are locations of potential weakness for the entire bridge deck but relatively little work has been carried out in this area. In the current practice, the in-situ stitches are usually designed to be capable of sustaining considerable sagging moment but only minimal hogging moment. Therefore, failure of these joints is possible under exceptional circumstances when the hogging moment is high, which may potentially trigger a progressive collapse. In the light of this, an extensive experimental study on the structural behaviour of the in-situ concrete stitches has been carried out. This paper focuses on the behaviour of stitches under direct shear. The effects of various parameters on the shear strength and failure characteristics were studied. Details of the experiments and other preliminary conclusions drawn based on analysis of the present results are presented in this paper. © 2011 Taylor & Francis Group, London.