Abstract
The instrumental seismic intensity by JMA is used the filter of three types which consist of high cut, low cut and period function. An extended function of the low cut filter is used to evaluate the effect of long-period range on seismic intensity in the paper. An asymptotic filter processing of acceleration in the extended function is proposed to express the seismic intensity corresponding to velocity and displacement. The seismic intensity level using the running r.m.s. method is applied to clarify the effect of various frequency weighted acceleration on seismic intensity. The seismic intensity level to velocity and displacement is also discussed by comparing with spectral characteristics.
