Flexural behaviour of profiled steel–concrete composite beams: tests and simulation

Although steel–concrete composite beams are widely used, the research on the synergistic effect of stud spacing and concrete strength on the flexural performance of profiled steel–concrete composite beams is not yet sufficiently in depth. To address this gap, three specimens (ZH1, ZH2, ZH3) were designed. Through four-point bending tests, Abaqus simulations and parameter analyses, the effects of stud spacing (224 mm × 80 mm, 504 mm × 80 mm) and concrete strength (C40, C50) on failure modes, crack propagation, ultimate bearing capacity, and so on, were investigated. In the simulation, the damage plastic model was adopted for concrete and the double-line model for steel. The results show that the spacing of the stud significantly affects the crack resistance and load-bearing capacity. The cracking load of ZH1 is 31% higher than that of ZH2, and its ultimate bearing capacity is 17.5% higher than that of ZH2. High-strength concrete enhances crack resistance but reduces ductility. The simulation results are in good agreement with the experimental data, verifying the accuracy of the model. Parameter analysis indicates that reducing the bolt spacing can enhance the flexural performance of the composite beam and is suitable for bridge engineering. This study provides theoretical and engineering references for the design of steel–concrete composite beams.