Nonlinear Dynamic Analysis Of Single-Layer Grid Shell Considering Support-frame

Grid shell has characteristics of great rigidity, light dead weight, magnificent structure, and good synthetic technology index. It is one of the main large span structural styles. At present, domestic documentation has getten many achievements in static and dynamic natures of grid shell. However, most of these research achievements are made separately on considerations of lower support-system and upper grid shell, imitate the support of grid shell with simply supported or fixed supported, and then independently calculate mechanical nature. As a matter of fact, most grid shells base on support-frame. Earthquake loading is passed to support-frame through ground motion, and then to grid shell through support-frame. If researching the earthquake resistant behavior of the spacious structure without considering the effects of support-frame, we will produce great deviation. Therefore, the research of dynamic analysis of grid shell with the effects of support-frame under earthquake effects has great importance.Because there are shortcomings in analysis of grid shell, in this passage, a system composed by shell and support-frame will be analyzed by using nonlinear finite element method and finite element program ANSYS.In the analysis, firstly, make the static analysis of the whole structure and get bending moment of beam end; secondly, make the model analysis and find out its free vibration and natural frequency; thirdly, figure out the damping ratio of the single-layer shell with support-frame by using the method of potential energy weighted; lastly, make the dynamic analysis of the whole structural system to get nodal displacement, nodal acceleration and axial force of each pole. Work out the time travel curve of the nodal displacement, the time travel curve of the nodal acceleration and the time travel curve of the motional internal force of the bar to find out the earthquake resistant behavior of the support-frame to the shell. In addition, alter the rigidities of frame to get the earthquake resistant behavior of the shell with the different rigidities of frame.Moreover, the research on grid shell with support-frame has been put into prospects.