Title: Shear Strength of Dry and Epoxy Joints for Ultra-High- Performance Fiber-Reinforced Concrete

Author(s): Balamurugan A. Gopal, Farzad Hejazi, Milad Hafezolghorani, and Yen Lei Voo

Publication: Structural Journal

Volume: 117

Issue: 1

Appears on pages(s): 279-288

Keywords: bridges; dry; epoxy; joint; precast; shear keys; shear strength; ultra-high-performance fiber-reinforced concrete (UHPFRC)

DOI: 10.14359/51718078

Date: 1/1/2020

Abstract:
Joints between precast segmental bridge girders (PSBGs) represent the locations of discontinuity through which compression and shear forces are transmitted. Therefore, knowledge of the joint behavior to accurately predict the response of PSBGs is essential. The aim of this research is to investigate the shear behavior, shear capacity, and shear-transfer mechanisms of the ultra-high-performance fiber-reinforced concrete (UHPFRC) keyed dry and epoxy joints. For this purpose, a series of full-scale UHPFRC keyed joint specimens were manufactured and tested with three variable parameters—namely, number of shear keys, confining stress, and the type of joint (dry or epoxy). The observations from experimental tests showed that the capacity of the UHPFRC keyed joints increased with increasing confining pressure applied across the joint, number of shear keys, and the epoxy layers applied on joints. Furthermore, a new design shear model for UHPFRC precast segmental bridges was developed and validated with experimental data.