A Practical Method for Assessment of Seismic-Induced Deformations of Underground Structures

The deformations of underground structures during seismic events are largely determined by the relative stiffness between the structure and the surrounding ground. A new analytical solution has been developed to estimate the deformations of buried structures. Soils exhibit a marked non-linear hysteretic behavior with cycles of loading. Such behavior can be incorporated into the analysis by an iterative scheme where the soils' shear stiffness is reduced with the structure's deformations. Initial verification of the method is done by comparing its predictions with those from a dynamic numerical analysis of the failure of the Daikai station in Kobe during the 1995 earthquake.