Response of typical sites to different earthquake motion input

A lot of studies on site soil nonlinear characteristics show that the site soil nonlinear effect become more and more obvious with the increase of earthquake excitation. For the first time, soil nonlinear behavior was discovered by the geotechnical engineers from laboratory tests, and then the seismologists confirmed it by analyzing the record data from strong motion observation. Generally speaking, the site soil nonlinear behavior will appear beyond an acceleration value, however, to different sites, there will be different earthquake motion input levels causing site soil nonlinear behavior. In this paper, a method is proposed to determine the corresponding earthquake motion input threshold in typical sites, based on the relationship between the shear wave velocity variation ratio and the earthquake excitation.