Analysis Of Anti-seismic Response For Considering Spatial Effect For Aqueduct

The seismic input is the precondition and base of structural response, ft is assumed in the conventional coherent-vibration input that all of the support points have the same ground movements, while carrying on the analysis of the large aqueduct structure to response of earthquake. This is equal to treat foundation as rigid body. If the structural size is far smaller than the wavelength of earthquake, this kind of hypothesis can be accepted. Actually, because the difference of the seismic character and geology and seismic transmission, the ingoing seismic wave is variable on the time and space, even other conditions are completely consistent, the time which each support point of aqueduct receive seismic wave is fall behind each other, because the distance of support points to the focus of earthquake is different, in same time, the movement which received by each support point is different, this is the question of multi-support seismic input. Using ANS YS soft ware and basing on the model of the Ming-he aqueduct, this paper founds seventeen-span model. Basing on the modal analysis of the structure, according to Ansys Parameter Design Language, the program of coherent-vibration input and multi-support seismic input are compiled. Using these programs, this paper calculates the dynamic response of model. In the analysis of multi-support seismic input, this paper analyses the influence of velocity of seismic wave on the response of earthquake. As key nodes, fourteen nodes are chosen, comparing change of coherent-vibration input and multi-support seismic input, analyzing the influence on the model via changing the velocity of seismic wave. Analysis results in the conclusion: the natural period is almost the same as the predominant period of seismic wave, the first ten modes of vibration are lateral. In the dynamic analysis, the result of multi-support input is larger than coherent-vibration input While velocity of seismic wave changes, for each key node, transverse displacement is larger than vertical displacement, with the increasing of velocity, transverse displacement is decreasing, as a whole, vertical displacement also has decreasing trend; for transverse acceleration, under the function of the first four velocity, the maximal value is decreasing smoothly, as velocity is equal to 2000m/s, it increases for little range ,which as twice to three times as velocity is equal to 200m/s; for vertical acceleration, with increasing of velocity, the maximal value decreases significantly; for transverse internal force, transverse moment, with the increasing of velocity, they decrease; longitudinal...