Research On Static And Seismic Behavior Of Pretensioned Cylinderical Reticulated Mega-structure

The prestensioned cylinderical reticulated mega-structure is composed of reticulated mega-structure and cable-strut tensile structure, which have advantages of both two structure forms. The new structure has reasonable structure force and can across larger space compared to the non-prestressed structure. Besides, the economic effieieney are significently improved in this structure. Based on the above benefits, the pretensioned reticulated mega-structure will have a good prospect and will be widely used in the further.By using ANSYS and the finite element theory to analysis the proprety of this structure. The main research work are as follows:(1) The difference of mechanics behavior between the reticulated mega-structure and the prestensioned reticulated mega-structure under four different load combination are analyzed in detail. Also,the influenee of kinds of parameters including the rise-span ration,prestress,height of struts are studied in order to obtain the difference proprety of the structure in two different cable arrangement.(2)The stability preformance is one of the main problem in desigen of spatial latticed shell. In order to reseaech the the bucking process of the structure,the eigenvalue buckling analysis and non-linear buckling analysis are carried out.First,using eigenvalue buckling analysis to get the theoretical bukling load of the structre with variable parameters.Then the nonlinear full range analysis with both geometric and material nonlinearity are considered, and the load-displacement path of the structure is analyzed by using the the Newton-Raphson and Arc-length method.Through which thestructure ultimate load-carrying capacity will be obtained.Besides,it also considering the influence of initial geometric defects,and half-span load etc to the stability of the structure.(3)The dynamic characteristics of prestensioned reticulated mega-structure are analyzed in this paper. a series of parameter analysis are carried out for the alteration regularity of natural vibration of the structure.Compared the vibration modes between the prestressed structure and traditional structure at last.(4)One of the seismic calculation methods –response spectrum analysis is used to analyse the seismic response of prestensioned reticulated mega-structure under lateral seismic action and vertical seismic action.(5)The elastoplatic response under frequent seismic actions of structure are calculated with the time-history analysis method.At last,compared the result of vibration mode-decomposition-response-spectra-method and time-history method.Some conclusions are summarized at the end of the thesis,and the problems which should studied in the future are also proposed,and hope to provide some reference for the engineering design.