Shear behaviour of trapezoidal column panels. II: Parametric study and cruciform element

• Characterization of the shear behaviour of trapezoidal column panels
• Proposal of a general semi-rigid mechanical model for joints with beams of unequal depths
• Parametric analysis and calibration of the mechanical model
• Development of a cruciform element for frame analysis of steel structures
• Numerical simulations and experimental results assess the accuracy and efficiency of the cruciform element.

In recent years a considerable effort has been dedicated to improve the knowledge on the behaviour of semi-rigid steel connections by techniques such as the component method. One of the most important components of the connections is the column web under shear. This component has a well-known and defined behaviour for the case of rectangular panels, which results in internal beam to column joints with beams of equal depth. However, when the right and left beams have different depths the shear panel becomes trapezoidal, and the application of the formulation corresponding to rectangular panels produces inaccurate results. The results of different laboratory tests and finite element simulations have been shown in the companion Part I paper. Also a mechanical model was proposed to characterize its behaviour.In the present work, the results of a wide parametric study, carried out by means of calibrated finite elements models, are shown. These results form the basis to characterize the different components, and define the analytical expressions for the stiffness of the proposed mechanical model. Additionally, a cruciform finite element has been developed that captures the behaviour of the proposed mechanical model. This general cruciform element is suitable for semi-rigid connections and can be used for the global analysis of semi-rigid steel frames. Finally, this approach is applied to several practical cases and the results are shown.