Full scale testing of ultra-high performance concrete closure joint for prefabricated full-depth precast concrete bridge deck panel system

Abstract

The main objective of the transverse joint between prefabricated full-depth precast concrete deck panels is to prevent the relative vertical movement between the panels and to transfer the loads between adjacent panels without cracking. The most common failure mode for these types of joints during their service life are the interface cracks. Such cracks serve as a conduit for ingress of water into the superstructure, leading to further deterioration requiring frequent maintenance. UHPC is known for its high tensile and bond strengths and is often considered as a joint fill material that has the potential to make this connection more durable. This research has been initiated to investigate if closure joints cast using UHPC material can compete with the performance of monolithic deck systems. The experimental program consisted of two full-scale concrete bridge decks that were statically tested until failure. One bridge deck was a jointed panel deck (JPD) consisting of two half-size panels connected by UHPC closure joint, while the control deck was a full panel deck (FPD) cast as one monolithic specimen. Both decks were connected to the steel girders with UHPC shear pockets that contained four to six shear studs welded to the girder flange. The JPD had rectangular tapered shear pockets and the FPD had circular shaped pockets. The results indicated that the JPD and FPD reached the same ultimate loads, and both failed via concrete punching at the load point situated adjacent to the closure joint of JPD. The results demonstrated that using UHPC closure joint resulted in similar performance and behaviour under loading as the monolithic deck. The interfacial failure was not indicated even at ultimate loads. This confirms the ability of the UHPC closure joint to transfer the load to the adjacent panel. The results also indicated the use of circular or rectangular pockets led to similar behaviours.