Single Layer Spherical Reticulated Shell Under Wind And Snow Load Stability Analysis

With the development of scientific technologies,reticulated shell structures has become lighter,thinner and long-span.The stability of reticulated shells has become the focus of reticulated shell designs.The static stability has established a relatively complete theoretical system thanks to many experts’ relentless efforts on it.However,due to the limitations of experimental conditions and calculation conditions,the problem of dynamic stability of reticulated shells remains,and the theoretical system has not developed well enough.Since the reticulated shell structure belongs to defect-sensitive materials,the problem of uneven distribution of the dynamic load on the reticulated shell structure becomes more prominent,and it often becomes a control load for the instability and collapse of the reticulated shell.Therefore,it is of great practical significance to study the dynamic stability of long-span reticulated shells under dynamic loads.The study of the dynamic stability of the reticulated shell under earthquake has formed a relatively mature theory.The distribution pattern of wind-snow combination load on the reticulated shell structure is more complicated,and it has a stronger effect on the heterogeneity of the reticulated shell.It has not yet formed an effective analysis method.Therefore,this paper analyzes the dynamic stability of a single-layer reticulated shell structure from the wind-snow load.1)A parametric user interface program was programmed using ANSYS’s own secondary development language APDL.The self-vibration characteristics of the reticulated shell were systematically analyzed,and the resonant frequency of the reticulated shell structure was found out.2)through the buckling analysis and nonlinear buckling analysis of the reticulated shell structure,the ultimate bearing capacity of the structure is calculated.The factors that affect the buckling of the reticulated shell are compared and analyzed,and the difference of the ultimate bearing capacity of the linear and nonlinear buckling structures is analyzed.3)Analyze the time-displacement characteristic curve when the reticulated shell structure is subjected to basic dynamic load(step load,harmonic load).For the reticulated shell under the basic dynamic loading,the effects of the initial defects and whether they are in the resonance region on the dynamic stability of the structure are compared and analyzed.4)Analyze the influence of various factors on wind load,and use MATLAB software to realize the numerical calculation of the wind load of Schwedler type single-layer spherical reticulated shell structure and the calculation of the uneven distribution of snow load on the surface of reticulated shell.5)by using the finite element software ANSYS analysis under wind load,biting,type of single-layer spherical reticulated shells of different geometric parameters(bar cross-sectional area,the rise-span ratio and span)influence on structure dynamic stability.