The Interstate Highway System plays a vital role in our economic development by providing a continuous corridor for transporting goods and services. Currently, there is a need for repair and expansion of the existing highways, which include all bridges along its path. Because of the high demand for the highway system, repair and expansion must occur rapidly and efficiently. In recent years, precast bridge deck systems have become an efficient way to reduce construction time during repair. This thesis presents the experimental research of the behavior of the U-Bar joint detail used in precast bridge deck systems. This detail consists of staggered reinforcement extending beyond the precast deck portion into the joint. Six specimens utilizing the U-Bar detail were constructed and tested. Three specimens were tested in flexure to simulate the forces applied in a longitudinal deck joint, while three specimens were tested in pure tension to simulate the forces experienced in a transverse deck joint located over an interior pier. A tight 180° bend at 3db was desired in order to minimize the thickness of the deck. To achieve this tight bend, deformed wire reinforcement was chosen for the U-Bar detail due to the favorable material properties of deformed wire reinforcement. The purpose of the testing was to determine if the joint details could generate a precast deck system that could emulate the monolithic cast-in-place deck systems already in use. For monolithic behavior in a precast deck system, the joints must be able transfer shear, tension and moments. In this research, the joint overlap length was the most dominant variable, and should not be less than 152.4 mm (6”). The precast bridge deck joint should consist of high strength concrete with f’c of at least 68.9 MPa (10 ksi). The longitudinal reinforcement spacing should be no greater than 152.4 mm (6”).

The Interstate Highway System plays a vital role in our economic development by providing a continuous corridor for transporting goods and services. Currently, there is a need for repair and expansion of the existing highways, which include all bridges along its path. Because of the high demand for the highway system, repair and expansion must occur rapidly and efficiently. In recent years, precast bridge deck systems have become an efficient way to reduce construction time during repair. This thesis presents the experimental research of the behavior of the U-Bar joint detail used in precast bridge deck systems. This detail consists of staggered reinforcement extending beyond the precast deck portion into the joint. Six specimens utilizing the U-Bar detail were constructed and tested. Three specimens were tested in flexure to simulate the forces applied in a longitudinal deck joint, while three specimens were tested in pure tension to simulate the forces experienced in a transverse deck joint located over an interior pier. A tight 180° bend at 3db was desired in order to minimize the thickness of the deck. To achieve this tight bend, deformed wire reinforcement was chosen for the U-Bar detail due to the favorable material properties of deformed wire reinforcement. The purpose of the testing was to determine if the joint details could generate a precast deck system that could emulate the monolithic cast-in-place deck systems already in use. For monolithic behavior in a precast deck system, the joints must be able transfer shear, tension and moments. In this research, the joint overlap length was the most dominant variable, and should not be less than 152.4 mm (6”). The precast bridge deck joint should consist of high strength concrete with f’c of at least 68.9 MPa (10 ksi). The longitudinal reinforcement spacing should be no greater than 152.4 mm (6”).

The purpose of this research was to identify the types of joints available for use on concrete bridge decks and to investigate the performance characteristics of each type, including primary functions and movement ranges. Eleven reports on joint performance published by state departments of transportation and universities nationwide were analyzed in order to obtain information on joint performance problems typically encountered by state transportation agencies. In addition, test methods and specifications provided by the American Society for Testing and Materials (ASTM) were reviewed for application by bridge engineers to ensure the adequacy of deck joints. The research indicates that compression seals should be used to accommodate movements less than 2 in., while strip seals should be used for movements up to 4 in. A lubricant conforming to ASTM D 4070, Standard Specification for Adhesive Lubricant for Installation of Preformed Elastomeric Bridge Compression Seals in Concrete Structures, should be applied during installation of compression and strip seals. Finger joints with troughs should be used instead of reinforced elastomeric joints and modular elastomeric joints for movements greater than 4 in. To maximize the performance of finger joints, ensuring adequate structural properties of the finger plates and proper installation of the troughs is necessary. When Utah Department of Transportation (UDOT) engineers conduct in-house experiments on bridge deck joints in the future, they should be more consistent and provide more information about the bridge structures in reports, including, for example, the anticipated deck movements, average daily traffic, and design loads for the bridges. Also, UDOT should establish a consistent evaluation program for investigating joint products during the approval process. The program should include quantitative measurements including, but not limited to, debris accumulation, adhesion and cohesion of the joint material, condition of anchorages and header materials, watertightness of the joints, condition of the concrete edges of the deck, deterioration of substructures, ride quality, noise level under travel, and general appearance of the joints. These experimental data should then be thoroughly documented in the resulting reports.