Experiment and numerical analysis on flexural behavior of cold-formed thin-walled C-shaped steel-paper straw board composite floors

As a new green material, steel-paper straw board (PSB) composite structures are widely used in practical engineering. This study proposed a new cold-formed thin-walled C-shaped steel-paper straw board (CFCSPSB) composite floor. To study its mechanical properties, flexural experiments were conducted on three composite floors. The experimental results showed that the combined effect of PSB and cold-formed thin-walled C-shaped steel (CFCS) beam was good, and the local buckling caused by the restraint effect of PSB on the CFCS beam was an important factor for the failure of the composite floor. On this basis, the composite floor was investigated by finite element analysis (FEA) software ANSYS, and the FEA results were consistent with the experimental results. Then, the effect of different factors on the flexural capacity of the composite floor was analysed by ANSYS. The obtained results showed that reducing the screw spacing and floor span, or increasing the CFCS beam cross-sectional size, web height of CFCS beam, and CFCS thickness could improve the flexural capacity of composite floors, and the calculation formula of flexural capacity for the composite floor was proposed.