Experimental Study of Local Force Transmission Mechanism of Steel-concrete Connection in Hybrid Continuous Rigid Frame Bridge

Abstract:

Three specimens of steel-concrete connection with different structures were designed to analyze the effects of connectors and back bearing plates on force transmission in the connection. It is shown that under 1.80 times of the design load， the connection in practical engineering is in the elastic state； when the axial force is 4.65 times of the design load and the shear force is 1.80 times of the design load， the connection reaches the elastic limit state； when the axial force is 6.65 times of the design load， the concrete inside the steel cells in the connection collapses and reaches the failure state. The back bearing plate is the most important component for axial force transmission in the structure. The back bearing plate bears 50%~60% of the axial force in the elastic stage， while the back bearing plate bears 35%~42% of the axial force in the plastic phase. In the mixed joint mode of perfobond plate connectors and stud connectors， the stud connectors played a minor role. The connection and force transmission between the steel box plates and the filled concrete could be realized by only setting the perfobond plate connectors.

Key words:rigid frame bridge;hybrid beam;steel-concrete connection;bearing capacity;force transmission mechanism