Experimental and Numerical Study of the Flexural Behavior of a Full-Scale Steel-Concrete Composite Beam

This study investigates the flexural behavior of a full-scale simply supported steel-concrete composite beam (SCCB) under monotonic loading. The deflection, strain, and relative slip of the SCCB were measured by sensors, and the digital image correlation (DIC) technique was used to monitor the full-field displacement, strain contours, and mid-span deflections. After matching the data of the DIC analysis, the finite element method was used to track the displacement, strain fields, and evolution process of the whole model. The results indicate that the shear stiffness of the group studs is highly correlated with the flexural behavior of the SCCB. The area moment of inertia of the steel beam has the greatest influence on the flexural capacity of the SCCB. Furthermore, it was found that increasing the concrete strength, stud density, and area moment of inertia of the steel beam can inhibit the occurrence of the tensile damage of the concrete slab, while improving the area moment of inertia of the concrete slab has a contrary effect. Moreover, increasing the stud density can not only improve the initial overall stiffness of the SCCB, but can also reduce the attenuation of the overall stiffness before the yield of the steel beam.