Abstract: This paper puts forward a kind of steel-RPC composite deck with a smooth-plate shear-force connector. The structure can not only solve asphalt pavement's disease of a steel bridge, but also can improve the deck's lateral stiffness, being help for easing the stress concentration and fatigue cracking at the place of U rib stiffeners. Based on this structure, a push-out test for smooth-plate shear-force connectors was conducted. 6 specimens were divided into two groups by the connectors' thickness of 4mm and 10mm. The test inspected the thickness's impact on shear bearing capacity and failure mode. The results show that the root of the connector will be yielded in tension when the connector is thin, that RPC under the connector is crushed when the connector is thick, and that the working mechanism is similar to that of steel fittings. Comparing a 10mm thickness connector with a 4mm thickness one, the bearing capacity is improved 43.6%, the stiffness of shear is improved 35%, and ductility decreased slightly, but two sets of test piece's ductility factor are both greater than 3.5. Finally, a simplified formula for smooth-plate shear-force connector's shear bearing-capacity is given, and the calculation result is more secure than test results, which can provide a reference for the design.