Experiment Research And Theoretical Analysis On Multi-Support And Multi-Dimensional Earthquake Of Large Span Structures

In order to satisfy the various architectural and function demands, the large-span bridge structure such as the stadium roof, bridge occupy the important components in the contemporary engineering, while the design span and size of new structure are rise in nowadays. Earthquake is one of the natural disasters against humanity community, which often cause huge loss of lives and property. If a bridge was destroyed in an earthquake, it will not only bring directly huge economic-losses, but also would seriously affect disaster emergency, post-earthquake relief work and production resuming. With the number of large-span structures increasing sharply, study on the seismic response characteristics of these structure types are called the out.Compared to the uniform excitation and one-way seismic wave excitation, multidimensional and multipoint earthquake excitation is more in line with the actual earthquake input. At present, both at home and abroad the seismic study on response of large-span structures to the multidimensional and multipoint earthquake excitation was limited to theoretical and numerical simulation only. Just because the limits of equipment, the multi-dimensional or multi-point shaking table test for the large-span structure has been in a "barren rock" of the situation.On multi-input study, set up the 3D numerical model of the practical engineering Qiandao Lake arch bridge, calculate the Qiandao Lake arch bridge response to earthquake by random method and time history analysis method. A long-span arch bridge reduced scale model is adopted in this paper to the shaking table test. And set up the numerical model to computer the corresponding results with finite element software. On multi-dimensional seismic area, this paper focused on national stadium roof by a big proportion model of the shaking table tests. Excited the stadium roof by the distribution of vertical, horizontal earthquake, as well as vertical and horizontal parallel to the seismic shock, analyze the seismic response characteristics with different seismic wave and different boundary conditions.By above research, achievements are follows:1. Set up the finite element model (FEM) of QianDaohu bridge which is long span concrete filled steel tube arch bridge. Analyze the traveling wave effect and stochastic response. Gain the conclusion that apparent wave velocity can increase the seismic response in a certain range. 2. Complete a long-span arch bridge model shaking table test and FEM numerical analysis. Get the dynamic response of transverse bridge to sinusoidal wave, the traveling wave effect and attenuation wave effect. The computer results are well in accordance with the test results.3. Design the shaking table test for the National Stadium roof which is large span two-way beam string structure with vertical, level, vertical-level two-direction earthquake excitation (its scale is so grand to be rare at home and abroad). And the numerical analysis was carried out. The structure seismic response characteristics were obtained.4. By the shaking table test and FEM analysis, the effect of support condition such as slide hinge support, hinge support and fixed support on the seismic response of the roof were achieved, which can be referred to the seismic design of the similar projects.