Model Test for Steel-Concrete Joint Section of Hybrid Girder Cable-Stayed Bridge

The main bridge of the Third Wanzhou Changjiang River Highway Bridge is a hybrid girder cable-stayed bridge with a main span of 730 m. The steel-concrete joint section is partially filled with concrete and equipped with rear-bearing plates. To examine the mechanical property of the steel-concrete joint section, a 1:4 scale model was prepared to carry out the load combination tests of maximum bending moment under the limit state of 1.0 and 1.4 times of load bearing capacity. ANSYS was used to establish the finite element model of the steel-concrete joint section to analyze the stress, deformation and interface slip in the steel-concrete joint section. The results show that the measured values are roughly consistent with the calculated values. Under the limit state of 1.0 times of the load combination of the maximum bending moment, the steel-concrete joint section is basically in elastic load bearing condition, and the stress is transferred from concrete beam to steel beam through the steel-concrete joint section evenly and smoothly. Under the limit state of 1.4 times of the load combination of the maximum bending moment, no cracks occur in the model concrete structure, and the stress of the steel structure does not exceed the design value suggested in the code. The deformation and interface slip of the steel-concrete joint section are small, showing good working performance. © 2019, Journal Press, China Railway Bridge Science Research Institute, Ltd. All right reserved.