Soil-Structure Interaction Analysis Of Nuclear Reactor Structure Subjected To Obliquely Incident Seismic Wave

Realization of the artificial boundary condition and the wave input are critical to Soil-Structure Interaction Analysis of nuclear reactor structure.To determine the wave input,one-dimensional or two-dimensional free-field problem is always analyzed,for vertically-incident plane waves or obliquely-incident direction parallel to the plane of two axes,which can not account for the arbitrary incident direction in three-dimensional problem.An input method of plane seismic wave incident in arbitrary direction is proposed in this paper.Combined with lumped-mass explicit FEM,the input for transmitting boundary and viscous-spring artificial boundary are realized.The main work is as follows:(1)Based on the basic theory of viscoelastic artificial boundary,the plane containing arbitrary incident direction and the coordinate vertical axis is selected.First,the two-dimensional free-field problem is analyzed through transfer matrix method.Then,the three-dimensional free-field motion is calculated by transformation between two coordinate systems.The transformation includes the displacement,speed and stress,which plays the role as the input for three-dimensional scattering problem.Furthermore,the realization of transmitting boundary condition and viscoelastic boundary wave input is given to realize the input of incident wave scattering problem subjected to obliquely incident seismic wave.(2)For a given nuclear structure model,the parallel technique is used to analyze soil-structure dynamic interaction under space oblique incident seismic wave.The influence of the incident angle of the seismic wave has been discussed on response of the soil,foundation and structure.The results show that the angle of space oblique incident seismic wave has a great influence on the response of soil-foundation-nuclear structure system(3)The frequency response function is obtained according to the results of linear soil-structure dynamic interaction analysis of nuclear power structure under the pulse input.Then the linear system response of soil-foundation-nuclear structure under designing seismic wave is obtained together with the related-point Floor spectrum,which can provide input for the seismic analysis of related equipment.