According to the practice of vertical shaft engineering, two types of composite structural model specimens of steel beam and slab are designed and made. According to whether shear connectors are set between steel skeleton and concrete slab, the two specimens are divided into two types: the shear model without spot welding of beam and slab, and the shear model with intesgral casting of beam and slab. Through the uniaxial static loading test at three-point bending, the flexural capacity of the structure was obtained, and the load-deflection curve and load-strain curve of the mid-span were plotted to analyze the failure characteristics. Through the comparative test, it can be seen that the installation of shear connectors can effectively improve the integrity of the structure and the flexural bearing capacity, delay the cracking time of concrete slabs and slow down the development of cracks. Reducing the height of the section can improve the stability of the structure and increase the utilization rate of the working space.