Effect of Interface Properties on Structural Behavior of Prefabricated Composite Girders with Deck-to-Girder Non-interference Interface Connections

Abstract

Recently, significant research has focused on developing durable and resilient solutions for highway bridge construction and rehabilitation worldwide. Among these, prefabricated composite girders with innovative deck-to-girder non-interference interface connections have been proposed to enhance constructability by removing on-site obstacles. In this study, finite element modeling of the deck-to-girder non-interference interface connections was set up to simulate the interface properties which are verified through recently conducted experimental study results of the monolithic-scale test. A series of numerical parametric studies were performed to investigate the effect of interface properties on the structural behavior of prefabricated composite girders with deck-to-girder non-interference interface connections. By protecting the transverse deck rebars that take more significant role to hold the deck flexural strength, loop type interface intercrossing rebars have been adopted to secure a higher performance non-interference connections. The interactions and correlations of the interface surface properties and the loop-type inter-cross rebars have been thoroughly investigated through a series of parametric studies. It was found from the parametric studies that the loop-type interface rebars can minimize the impacts on the transverse deck reinforcements due to critical shear plane actions even though 50% lower friction or cohesion capacities would be assumed. Thus, it is simultaneously proved that the influence on the flexural behavior of prefabricated composite girders like this case was minimal, when the lower limit range of interface properties such as stiffness coefficient, peak value of traction, and effective separation in case of complete failure was applied. Since it has been seen that the ultimate strains in the loop reinforcement rebars can reach beyond the yield strain states in the lower case of friction capacity, indicating that slip increases, thereby affecting the stiffness of the girder. The management of non-shrink hydraulic injection grout is important. This study suggests a desirable simulation and approach of such interface surfaces to evaluate the structural behaviors and nominal resistances of the prefabricated and assembled girders.