Research On The Effect Of Joints Stiffness On The Stability Of Reticulated Shells

Owning to some prominent properties of such structures, such as low mass, high rigidity and pleasing appearance, etc., recently there has been an increasing application of reticulated shells in engineering.All kinds of connection ways exist in reticulated shells. No matter what kinds of connection ways applied, joints stiffness on the connection will considerably affect the bearing capacity of such structures. In designing, single-layer reticulated shells are considered as space frames with perfectly rigid connection, while double-layer reticulated shells are modeled as space trusses with frictionless pin connection for convinces. Actually, the semi-rigid connection is really the truth. Stability is regarded as one of the most capital elements during the design of reticulated shells. So it is very important to take into account the joints stiffness in the stability analysis, for the sake of theoretical research and engineering design.In this dissertation, stability research on reticulated shell structures is reviewed. In order to detect the critical points and trace the buckling equilibrium path, the arc-length method is introduced. The classical element connection model and joint connection model is investigated, based on which a new model is established and the semi-rigid connection matrix is derived.The arithmetic of how to consider the new model is designed grounded on the APDL in ANSYS, a general FEA program. Based on the theory and the arithmetic presented in the paper, a lot of bearing capacity of many types for reticulated shells under all kinds of joint stiffness is obtained, and a series of useful conclusions are drawn.Finally an experiment is conducted and numerical analysis of the experiment model is carried out. The comparison between numerical results and the experimental one shows that the method we put forward is feasible.