VERTICAL SEISMIC ACTION ANALYSIS OF THE STRUCTURE WITH FRAME-SUPPORTED TRANSFER FLOOR

摘要

The structure with frame-supported transfer floor performs relatively sensitivity to the vertical seismic action. In this paper, a series of framesupported transfer floor structure's threedimensional models are built with the aid of finite element analysis software SAP2000.By using modesuperposition response spectrum method and time history analysis method, their vertical seismic action is analyzed. Due to considering different seismic load cases combination, the differential rate of internal force is necessarily put forward and calculated. Those analyses and calculations present some perspectives as follows: the vertical seismic action of the transfer floor structure increases more remarkably than the horizontal seismic action does; when the transfer floor's span is larger (over 14m in the example of this paper), even in the region with seismic fortification intensity of 7-degree, especially 7.5-degree, the effect of vertical earthquake shouldn't be ignored; if the seismic code is applied mechanically and the vertical seismic action is ignored in that case, it will bring potential safety hazards, thus the adequate analyses shall be made on certain problems; the vertical seismic action behaves so significantly in the region with fortification intensity of 8-degree that it should be taken into account seriously no matter how large the transfer beam's span is.