Sensitivity of seismic foundation bearing demand using random vibration theory and time history methods

27 August 2013


SASSI2010 solves the Soil-Structure Interaction (SSI) problem in the frequency domain. The user may enter either an Input Response Spectra (IRS) for a solution using the method of Random Vibration Theory (RVT) or a time history that is compatible to the IRS. When using RVT, the user may request maximum forces; whereas, with the time history method, time histories of forces may be requested.
The purpose of this paper is to assess the differences in foundation bearing pressure demand obtained using the Random Vibration Theory (RVT) method and the time history method.
An SSI model representative of a deeply embedded nuclear structure is generated for the studies. A soft soil profile is considered in conjunction with a motion typical of the western United States (WUS). The total seismic bearing demand is computed using two methods. The first method is by direct output from SASSI2010. In the second method, the total force is computed by summing the reaction forces for every time step.

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August 18-23, 2013
Transactions, SMiRT-22
San Francisco, California, USA