Static And Dynamic Stability Analysis Of Sheet Space Structure

Sheet space structure system is a new type of structure system that emerged under the basic national circumstances of China and the development of international space structure.The design of the structure is inspired by the aviation field.Applied the principles of aviation structures to architectural structures,the new space structure system is obtained,which is light weight,high strength and economic.For remarkable good mechanical properties and economic advantages,an in-depth study on the key issues of this structure system is extremely important and conducive to the development of space structure in China.Imperfections are one of the important factors affecting the stability of sheet space structure.In this paper,the description and distribution features of stochastic imperfections are analyzed.A new method of stochastic imperfection analysis is proposed,which is called spherical truncated univariate normal stochastic imperfection analysis method.In this method,the initial geometric imperfections are described in spherical coordinates and the distribution function is assumed as truncated univariate normal,which is more realistic.Furthermore,the value method of ultimate load for stochastic imperfection analysis is studied to obtain the most dangerous imperfection model of sheet space structure.Studying the mechanical properties of sheet space structure needs large scale parametric analysis.In this paper,the parametric modeling of common geometric expanding types of sheet space structure is proposed,and the modeling program is compiled by APDL language,which lays a research foundation for large-scale parametric analysis.The static stability of spherical sheet space structure is studied by large scale parameterization.The variation rule of static stability ultimate load is studied with different structural parameters.The influence law of initial geometric imperfections on the static stability initial geometric imperfections of sheet space structure is obtained in the way of the most dangerous imperfection model of sheet space structure.The equivalent stiffness of sheet space structure is determined by method of simulated shell,and the fitting formula is carried out by analyzing the results data of large-scale parametric analysis.Finally,the practical design formula for the static stability ultimate load of sheet space structure is obtained,which is considering with the influence of the initial geometric imperfections.The wind resistance of sheet space structure is studied from two aspects of wind pressure coefficient and wind-induced vibration response.The calculation model of numerical wind tunnel is established,and the simulation data was compared with the experimental data to illustrate the validity of the numerical wind tunnel model,the calculation program of the numerical wind tunnel is compiled.Through the combination of the wind pressure coefficient and the wind speed time series of the structure,the load input of the wind-induced vibration response analysis and the transient dynamic analysis of the sheet space structure is completed.The vibration response is compared to reflect the difference between the wind-induced response of the spatial structure of the plate and the structure of the reticulated shell,and further explains the advantages of the spatial structure of the plate in terms of dynamic response.Finally,the influence of structural parameters which are damping ratio,span,and rise-span ratio on the wind-induced vibration response of sheet space structure is analyzed and studied.The influence law curve of wind vibration coefficient of sheet space structure is obtained which is affected by damping ratio,rise-span ratio and span of the structure.The dynamic stability of sheet space structure was analyzed by using BR criterion.The most dangerous dynamic load is obtained.The influence of dynamic stability critical load of sheet space structure is analyzed by considering the material nonlinearity.The effects of span,span ratio and initial imperfections on dynamic stability of sheet space structure were studied,and the variation law of the dynamic critical load of sheet space structure is obtained.The calculation process of parametric design method of sheet space structure needs the repeated use of finite element software,and the data processing of the large-scale parametric analysis is complicated.The C# programming language is used to design a special analysis software for the sheet space structure system,in which the command flow and data processing program of the corresponding CAE software are packaged into the software background.The key technology points including the visualization window,parameter transmission,file output and closed call program interface is solved,the software greatly improves the efficiency of sheet spatial structure analysis,and it provides the necessary promotion for the spread of sheet space structure system.