Dynamic Stability Analysis Of Large-span Suspend-dome Structure Under The Traveling Wave Seismic Excitation

As a new type of composite spatial structure form, which is based on the concept of integral tension structure, the suspend-dome structure integrates the upper single-layer spherical latticed shell structure and lower suspended structure. It’s mainly limited to small and medium span for the research of stability of suspend-dome structure under single-dimensional seismic excitation in past years. While the effect of spatial variation earthquake, especially for the traveling wave seismic excitation, should be considered for large-span suspend-dome structure. In this paper, dynamic stability characteristics of large-span suspend-dome structure considered the effect of single-dimensional and multi-dimensional are analyzed by means of the finite element software ANSYS. The main contents are as follows:1、In the reasonable value of the prestressed cables range, the suspend-dome with high value of the prestressed cables and rise-span ratio has a high bearing capacity, while the suspend-dome with high value of the prestressed cables and low value of rise-span ratio has a low bearing capacity. As for the suspend-dome with the same value of the prestressed cables and different rise-span ratio, the suspend-dome with high rise-span will has a strong bearing capacity under the same seismic wave.2、The suspend-dome with the same rise-span ratio and value of the prestressed cables will have a stronger capacity under the incentive of El-Centro wave than Los-Angeles natural seismic wave, mainly because the previous orders natural vibration frequency of large-span suspend-dome generally less than1s,whereas Los-Angeles natural seismic wave response spectrum value significantly greater than El-Centro seismic wave during0～1s.3、Considering the traveling wave seismic excitation, dynamic stabilities of suspend-dome of120m span under horizontal, vertical and three-dimensional seismic excitation is calculated respectively in the incentive action of different wave velocity compared to the effect of single-dimensional seismic excitation and the regular pattern of the effect of single-dimensional and multi-dimensional indicates that the wave passage effect of both the vertical, horizontal and three-dimensional earthquake decrease the bearing capacity of the structure, but the horizontal and three-dimensional one affects much more while the vertical one affects less, mainly because maybe seismic excitation make cable relax under the traveling wave seismic excitation. The bearing capacity of the structure under three-dimensional earthquake is extremely close to the bearing capacity of the structure under horizontal earthquake under the same condition. So the result indicates that the bearing capacity of the structure under three-dimensional earthquake is controlled by the horizontal component.