Analysis Of Multi-point Earthquake Excitation Of Long-span Spatial Structures

The influence of spatial variation of seismic ground motion on Long-span Spatial structures can't be neglected. This article focuses on the multi- point input earthquake time interval analysis of long span spatial structure. Comparison analysis between multi-point input and consistent input in carried, finally find beneficial conclusion.Under the multi- spots input function, the structure equation of motion cannot simply apply mechanically the motion equation of consistent input, the formula must reinfer.Based on the above theory, the parameter is set reasonably in application and a serial calculation measures are taken to improve the precision. The seismic response analysis of space structure are studied through the non-uniform time history method including 4 apparent velocity vapp=50m/s, 100m/s,150m/s and 200m/s.A Long-span gymnasium which will be built in our province is analyzed under both non-uniform excitation and simple support excitation. The number and distribution of frame with greatly different stress and the relation to the apparent velocity are studied. It shows that the influence of presdo-static displacement on the frames force near the base is great. Wave-passage effect is decreased with the increase of the apparent velocity. Incoherent effect is irrelative to the apparent velocity. And the safety is insure within the specific span while non-uniform excitation is substituted by simple support excitation.