Research Of Joints Of Steel Frames Transferring Force Outside Rectangular Tube Column

Steel structure has many advantages such as light weight, high strength, good seismicproperty, high industrialization, rapid construction, environment protection, sustainabledevelopment, high-tech involvement. Under the policies of steel structure and theimprovement of steel production, steel building develops rapidly. The design of steelstructure mainly includes two aspects. One is stability of components and the wholestructure, the other is joint performance's research. During the Northridge Earthquake in1994 and Hyogoken-Nanbu Earthquake in 1995, welding beam-column joints were greatlydestroyed. After surveys and researches on beam-column joints, technical measures andstrengthen measures to improve joint design were taken.In order to improve joints, there are two traditional methods. One is to strengthenjoints at the ends of beams; the other is to weaken beam parts near columns. Internal forcesbetween beams are mainly transferred by columns, failure of joints will occur mainly atbeam column joints.Traditional methods are changed in this dissertation. By adding plates on flanges ofbeams, a new steel frame joint, transferring force outside rectangle tube columns, is putforward. The internal forces between beams are mainly transferred by the adding plates.Traditional failure patterns were changed, that is to say joints will be broken at the point onthe beam where adding plates are connected.The non-linear finite element method program, ANSYS8.1 is used to analyze thejoints in this dissertation. Main works are following.1. Joint performances under the symmetry load are analyzed. Characters of their stressconcentration, stress distribution, failure modes and carting capacities were studied.2. By comparing of carrying capacities and stiffness of joints transferring forceoutside rectangle tube columns with those of traditional strengthening joints, reliability andsuperiority of these new joints are obvious.3. By analyzing joints with different widths, locations and thickness of the addingplates, their performances are studied further.By analyzing of these joints, effects of and sizes of adding plates are given. Furtherresearch of the joints could be done based on this dissertation.