Mechanical Performance Analysis And Optimization Of Steel Frame Beam-column And Column Base Joints

Steel frame joints have a direct effect on the strength stability and deformation of steel frame.In order to promote the overall performance of the steel frame structure,research on bolt welding connection beam-column joints and outsourced column base joints,finite element analysis method analyze the mechanical properties and structure of the node,and to simplify the node force transmission characteristics for related parameters into the steel frame as a whole in the link element model,analyzed the influence of the node to the whole structure.The main contents are as follows.The degree of stress concentration of the bolt-welded beam-column joints is smaller than that of the all-welded joints,and the angular stiffness of the all-welded beam-column joints is larger than that of the bolt-welded joints.In terms of beam-end flange structure,Wing reinforcement structure is the most conducive to improving the bearing capacity and seismic energy dissipation capacity of the joint,followed by the reinforcement-weakening structure of beam-end flange,and the worst one is the weakened structure of beam-end flange.When analyzing the effect of the bolt end distance on the joint,it is found that the end distance between 2.5d0 and 4d0 is the most unfavorable to the stress distribution on the joint plate,so the bolt end distance should be avoided as far as possible.Changing the strength of the connecting plate has a great influence on the bearing capacity of the joint and the uniform distribution of stress on the connecting plate,so the steel of the same size connecting plate should be selected not less than the strength of the steel column.The seismic performance and angular stiffness of the outsourced column base are greater than those of the exposed column foot.The flexural bearing capacity of exposed column foot is weakened in the absence of axial force.The ultimate bearing capacity and stress distribution of the joint are affected by the length of the bottom plate of the outsourced column base.When the length of bottom plate is 980mm,the bearing capacity and energy dissipation capacity of joints increase most obviously.The width-to-thickness ratio of the horizontal stiffeners of the outsourced column bases has no great influence on the bearing capacity and seismic capacity of the joints,only to prevent local yield,so its width-to-thickness ratio can be selected as the maximum in the code.The length of stud has an important effect on the bending resistance of reinforced concrete column.When the stud length is 120mm,the outsourced column base can obtain better seismic resistance and bearing capacity.According to the response spectrum method of seismic code,the influence of different construction nodes on the overall performance of steel frame is analyzed.It is found that bolt-welded rigid beam-column joints are more suitable for irregular steel frame buildings than all-welded rigid beam-column joints,while the outsourced column bases are not suitable for irregular buildings with small aspect ratio.Figure 86 Table 14 References 76...