Fininte Element Analysis Of The Endplate Connection Joint's Bearing Capacity

With continuous development of economy in China in recent years, the construction industry has gained rapid growth, especially the application of steel frames in residential and commercial buildings. As is known to all, the mechanical behaviors of joints in steel frames are very important to the whole structure. In traditional structural design, it is often assumed that the joints between the columns and beams are ideally rigid or hinged.Actually,the real behaviors of joints,especially of the extended endplate connections,which belong to semi-rigid connections,are just between the two formers. On the other hand,the application of semi-rigid connections in steel frames can increase the structural damping,lengthen the natural period,and reduce the vibration amplitude,so it is very favorable for aseismatic design. Since the endplate connection is related to the interaction among beams,columns,endplate and bolts,etc,and always accompanied by the frying phenomenon etc., there are no corresponding provisions about endplate connections in China Steel Structure Code(GB 50017-2003).Component method is most widely and efectively used for semi-rigid connections such as endplate connections.With this method,endplate connections are divided into single component, such as endplate, column flange, column web, etc,and the behavior of each component is a nalyzed individually,then these components are assembled to induces the M-θcharacteristics of the whole joint.This paper is focused on the M-θcharacteristics of endplate connections.The component method is used in order to establish a simple and effective formula for practical application.In this paper,first,the mechanical performance of high strength bolt is introduced and compared between the related provisions in GB 50017-2003 with LRFD(AISC,1994),and Eurocode3(1993).Then,based on the Kulak model,an important component of endplate connections,T-stub,is analyzed,and some improvements on estimating the plastic load-carrying capacity of the model are presented,which result in a preferable agreement with the test results.By a pplying some research achievement for Kulak model in this paper to the Yee and Melchers' model of the endplate connections, a simplified formula of M -θrelationship is obtained,and its efficiency is proved by theoretical analysis and experimental results.