Research On Static And Dynamic Performance Of Single-layer Semi-ellipsoidal Reticulated Shell

In recent years,most public buildings have adopted a single-layer reticulated shell structure.Because the reticulated shell structure has both the advantages of the grid structure and the thin shell structure,it has an indispensable position in the large-span spatial structure.This structure is not only beautiful in shape,smooth in flow,but also simple in construction and good in structure.However,with the extensive application of reticulated shell structures,research on regular reticulated shell structures such as spherical and ellipsoid surfaces is relatively mature,and research on irregular reticulated shell structures such as semi-ellipsoidal structures is less.If it possible to optimize the semi-ellipsoidal structure for more economical purposes.And if it possible to deal with stability problems of semi-ellipsoidal structures caused by node displacement deviation.And if it designed response to displacement deviation of nodes under earthquake action of semi-ellipsoidal structures.And if it based on the above questions of semi-ellipsoidal structures,this paper has done the following work:(1)As an example,this article takes the American Aviation Museum in Duxford.It abstract single-layer semi-ellipsoidal reticulated shell model.It drawed on the meshing of single-layer ellipsoidal reticulated shells.The semi-ellipsoidal reticulated shell structure is divided into: Ribbed type semi-ellipsoidal reticulated shell,Schwedler type semi-ellipsoidal reticulated shell,Lamella type semi-ellipsoidal reticulated shell,Kiewitt type semi-ellipsoidal reticulated shell,Three-way grid type semi-ellipsoidal reticulated shell,Geodesic type semi-ellipsoidal reticulated shell.The APDL language is used to compile the modeling macro program for the six semi-ellipsoidal reticulated shell structures.The realization of six semi-ellipsoid mesh shells can be automatically parametrically modeled.Then,It introduced a semi-ellipsoidal equation.It deduced the relationship between the geometric parameters of the semi-ellipsoidal reticulated shell structure.The spatial coordinates and structural length of each point of the ellipsoid are obtained.(2)Static analysis of six semi-ellipsoidal reticulated shell structures,using ANSYS software,with steel consumption of semi-ellipsoidal reticulated shell structure,length-to-span ratio,vector-span ratio,support conditions,boundary rod specifications and load distributionform as parameters To study these six parameters.It is found that the influence of these six parameter changes on the static performance of the semi-ellipsoidal reticulated shell structure,and it is concluded that it is beneficial to the actual structural engineering design and application.(3)The stability analysis of the half-ellipsoid reticulated shell structure,using the structure’s length-to-span ratio,vector-span ratio,supporting conditions and load distribution as parameters,study the influence of these four parameters on the eigenvalue buckling analysis of the structure;Long and short span ratio,vector-span ratio,supporting conditions,initial defects,load distribution and material nonlinearity are the parameters.These six parameters change the nonlinear analysis of the structure and the whole process of two types of semi-ellipsoidal reticulated shells at maximum buckling is obtained Load-displacement response curve,and obtained the influence law of six parameter changes on the semi-ellipsoidal reticulated shell stability and allowable bearing capacity and ultimate buckling.This provides a theoretical basis for actual engineering design.(4)The seismic response analysis of the semi-ellipsoidal reticulated shell structure was carried out.The dynamic characteristics of the structure were obtained through the analysis of the vibration mode participation coefficients,frequency spectrum characteristics and vibration mode characteristics of the two structures.Spectral analysis to obtain the damage characteristics of the structure under the X,Y,and Z earthquakes.Through the dynamic time-history analysis of the seismic response of the two semi-ellipsoidal lattice shell structures,the damage characteristics of the structures under the X,Y,and Z earthquake waves are obtained.This provides a theoretical basis for the seismic design of actual projects.