Análise numérica de ligações viga-pilar com dupla cantoneira e com chapa de topo estendida em estruturas de aço

Abstract

In order to evaluate their behavior when submitted to simple bending, this paper presents a numerical analysis of two beam-column connection types in steel structures, of double web-angle connections and of extended end-plate connections. It is widely known that the real behavior of a connection in steel structure is not exactly the one defined in idealized models, such as perfectly rigid or perfectly pinned. In fact, it demonstrates an intermediary behavior which is called semi-rigid. This way, the aforementioned connections were chosen because they represent the opposite idealizations in structural design. A connection with double web-angle is usually regarded as perfectly pinned, despite having a certain rotational stiffness that would classify it as semi-rigid, and an extended end-plate connection, usually assumed as perfectly rigid, may not have sufficient rotational stiffness, depending on its geometry, which would classify it as semi-rigid. Numerical analysis was carried out on the finite element method based program ANSYS®, in which contour conditions, beam length, material properties and manners to apply the pretension on bolts were changed to observe the variation in the connection behavior. In order to obtain results that are closer to real behavior, the numerical models used volumetric elements, considering material and geometrical non-linearity, contact between materials and bolt pretension. Displacements on the beam’s end and the moment-rotation curve obtained numerically were compared with experimental results present in literature and analytical models. It was observed that both the beam length and the manners to apply the pretension, either by temperature variation or using program’s pretension element, did not change the connection behavior. In addition, despite some differences, numerical models showed similar behavior to experimental results present in literature, demonstrating the potential of numerical analysis based on the Finite Element Method to obtain the behavior of the connections.