Structural Analysis Of Frame Considering Bending And Shearing Deformation Characteristics Of Joint

Semi-rigid connection is a kind of connect between rigid and pinned connections which widely exits in engineering practice. The advantage of semi-rigid connections has also got a great deal of research and approval. Many scholars at home and abroad have done a great deal of painstaking working and made a series of research results. The traditional study of semi-rigid connection is a series of explorations about rotating semi-rigid. But sometimes it can be found that the influence of the shear-slip relationships of semi-rigid joints on the structure can not been ignored.In this paper, a mechanical model composed of a bar element and two springs at each end is present which can be used to consider the bending and the shearing deformation of joint. Analyses of the element considering both the shear-slip relationships and the moment-rotation and shear-slip relationships of the joint are carried out using basic mechanics method for the first time. The stiffness matrixes of this two type elements are derived. Some reaction forces at the end of these elements are obtained when they are subjected to five kinds of different loads. The relation of displacement between the bar element and the joint is derived. The entire analysis of frames composed by this kind of element is present. Comparing with the method which uses panel zone of joints to consider the shearing deformation of joint in the structure, it can be see that this method using the element present in this paper has a advantage that the element number of structure does not increase.In this paper, two computational procedures for plane steel frame are programmed using the computer language VB respectively:considering the linear and the non-linear performance of the joint. For the second procedure, Newton-Raphson iterative method is used to solve non-linear equations. As an example, the linear and non-linear analyses of a structure are done. Displacements of nodes and the composing elements, as well as the force vectors of these elements are derived using the computational procedure programmed. When the load is imposed progressively, the corresponding load-displacement curve is drawn. By the comparing of the examples, it can be seen that the moment-rotation and the shear-slip relationship of joint can greatly affect the behavior of the structure. If these semi-rigid performances can be considered seriously, the result of analysis will be closer to that of practice engineering.