Seismic Response of a Rigid Steam Generator Suspended from a Simplified Supporting Structure

摘要

The loads in the vertical support rods and in the horizontal tie rods are investigated as a function of their geometric configuration when the base of a simple supporting structure is subjected to a set of earthquake accelerograms suitably normalized. Three dimensional linear equations of motion are derived assuming that the vertical support rods can carry compression, that the steam generator may be treated as a rigid body, and that the top girder system forms a rigid body. Numerical results are presented in a two-dimensional example. The main conclusions which can be made are that: (1) the dynamic loads in the vertical support rods are dependent upon the configuration of the horizontal tie rod with some configurations producing much smaller dynamic loads than others; (2) if the maximum acceleration of ground excitation is in the range of .3g, the influence of the unloading of some of the vertical support rods should be accounted for in the equations of motion including the deformation of the top support; and (3) attention should be given in design to the dynamic loads that the vertical support rod must carry.