Research Of Nature Frequency Calculating Model About Soil-superstructure Interaction

For a long time, the rigid ground assumption has been mostly adopted for earthquake response analysis in the common civil engineering design in which only the superstructure is considered in the model. However, real structure always interacts with foundation and soil, which form a integral system, so the rigid ground assumption must result in some inaccuracy. This problem has been drawing academic attention and leading to applicable results. With a large number of large-scale and complex structure emerging, the soil-superstructure interaction problem will be further addressed.Nowadays most research on soil-superstructure interaction focus on the algorithms, but in application using commercial analysis package is more feasible. The widely using of response spectrum method requires accurate natural vibration frequency of the structure, which would necessarily change when soil-superstructure interaction is considered. So the determination of natural vibration frequency is one of the difficulties in earthquake engineering.Focused on the problem above, this paper first present a review about the research of soil-superstructure interaction, after establishing a "no mass" model for natural vibration frequency with soil-superstructure interaction effects in consideration a verification of parameters and model is made using SAP2000.