Full-scale experimental study on shear behavior of multiple-keyed epoxy joints in precast concrete segmental bridges

Abstract

Precast concrete segmental bridges (PCSBs) have become a trend in bridge industry, the joint behavior between segments is critical to the mechanical performance of PCSBs. Compared with dry joints, epoxy joints are more widely used in practical engineering, but the researches on epoxy joints are relatively few. In this paper, an experimental investigation of the shear behavior of full-scale multiple-keyed epoxy joints under direct shear are presented, considering the parameters of joint type, confining stress, epoxy thickness, and key geometry. The crack patterns and failure modes of the test specimens were obtained and the influences of the parameters on the shear capacity were discussed. The existing formulas of joint shear capacity were assessed by the test results, and a new analytical prediction model that fully considers the uneven distribution of shear stress in the shear plane was derived based on Mohr’s stress circle, which can accurately predict the shear strength of epoxy joints.