The Stiffness Of The T-shaped Joint Joint Of The Circular Steel Tube And Its Influence On The Overall Performance Of The Hollow Truss

In Steel structure, joint connection mode is very important, because the joint failure could make the failure of a number of bars which associated with the joint, and could resulte in overall structural damage. As the steel structural members in a common connection node, the tubular joints design is a important step in steel structure design. Actually, tubular joints is a semi-rigid joints, and it has a certain bending stiffness. The shells which is used by the semi-rigid joints has a certain carrying capacity and it is different to the shells which is used by a rigid joints. So it is a great engineering application value that the tubular joints impact bending performance under axial force.Firstly, the unstiffened property of tubular joint stiffness and the importance of the research on Simulative Method of tubular joint stiffness are introduced. Three element of tubular joint stiffness are introduced, their advantage and disadvantage are compared. By the analysis of typical examples, the simulative result of shell element is similar to the Moment-curvature beam element, but the result of spring element is different to them, because effect of axial force for bending stiffness is not considered by the spring element. Moment-curvature beam element consider the impact of axial forces.Secondly, used common T- joints for the study in flat steel truss structure, used the shell element of the finite element software ADINA to establishe modle of tubular joints, and research how the geometric parameters of the structure and force parameters impact the joints of in-plane bending properties.Thirdly, used the Linear analysis of space structural design software 3D3 S and systematically analysis that the design parameters(include the way of bearing support,the mode of connection, span ratio of structure, depth-span ratio, the ratio of webs and chords,and the thickness of structure webs) impact the structural properties, and provide reference for further research and engineering staff.Finally, prepared with program which consider the stiffness of joints, and study the effect on the structure of joint stiffness and overall stability by ADINA. The structure of double nonlinear stability analysis couled result the different load- displacement curve of vierendeel Truss, included the way of bearing support, depth-span ratio of structure, adbominal-span ratio,the thickness of braces. The research shows that the Joints Stiffness has a great effect on the overall performance of the vierendeel truss structure.