Improve long periodic ground motion evaluation with the epicenter on the border between Fukushima and Ibaraki prefectures in seismic design of nuclear facilities

Kirita, Fumio; Tominaga, Masahiro; Yamazaki, Toshihiko; Seshimo, Kazuyoshi; Uryu, Mitsuru

JAEA-Research 2022-006, 61 Pages, 2023/02

JAEA-Research-2022-006.pdf:6.24MB

Nuclear Fuel Cycle Engineering Laboratories (NCL) has been observing ground motion for a long time. On the border from northern Ibaraki prefecture to Fukushima prefecture, inland crustal earthquakes occur less frequently until the 2011 off the Pacific coast of Tohoku Earthquake (hereinafter referred to as Tohoku Earthquake). After Tohoku Earthquake, aftershocks have become more frequent in this area, and in the Hamadori region of Fukushima earthquake that a remarkable long periodic component was observed in the NCL seismic observation record. Until now there were no such things that long periodic components were observed at the observation points near the epicenter of April 2011 Fukushima earthquake, but it was thought basin structure in deep basement around the NCL affected the propagation process to NCL by reflection survey result. As basement structure of NCL affected the seismic wave propagation process, the seismic wave repeatedly reflects and refracts. For that reason, long periodic components of seismic waves may be possibly amplified. In this study, in order to refine the long periodic ground motion evaluation, using a three dimensional ground structure model (3D model) that can reflect the shape of the deep basement structure around the NCL. When modeling 3D ground structure which has a width of about 80km and a length of about 110km and ranges from the epicenter area of April 2011 Fukushima earthquake to the northern coastal area of Ibaraki prefecture modeled, improved the optimum ground structure model using multiple observation records and performed simulation analysis.

Long-term monitoring of natural frequencies of a full-scale 4-story building E-defense experimental projects for steel buildings

Kirita, Fumio

no journal, , 

no abstracts in English

Amplitude dependence of natural frequency on a base-isolated building during earthquake

Kirita, Fumio; Uryu, Mitsuru; Yamazaki, Toshihiko; Nakanishi, Ryuji

no journal, , 

no abstracts in English

A Study on the response characteristics of base-isolated structures for earthquake motion, 2

Nakanishi, Ryuji; Uryu, Mitsuru; Yamazaki, Toshihiko; Hashimura, Hirohiko; Kirita, Fumio; Kojima, Keidai

no journal, , 

no abstracts in English

Long-term evaluation of natural frequency of a base-isolated building before and after the 2011 off the Pacific coast of Tohoku earthquake

Kirita, Fumio; Uryu, Mitsuru; Yamazaki, Toshihiko; Hashimura, Hirohiko; Nakanishi, Ryuji; Kojima, Keidai

no journal, , 

no abstracts in English

Performance evaluation of lead dampers on base-isolated building attacked by the 2011 off the Pacific coast of Tohoku earthquake, 2

Kirita, Fumio; Uryu, Mitsuru; Yamazaki, Toshihiko; Hashimura, Hirohiko; Nakanishi, Ryuji; Kojima, Keidai

no journal, , 

no abstracts in English

Performance evaluation of lead dampers on base-isolated building attacked by the 2011 off the Pacific coast of Tohoku earthquake, 4

Nakanishi, Ryuji; Uryu, Mitsuru; Yamazaki, Toshihiko; Hashimura, Hirohiko; Kirita, Fumio; Kojima, Keidai

no journal, , 

no abstracts in English

Evaluated source, path and site amplification factors using outcrop records at KiK-net in Ibaraki region

Yuzawa, Yutaka*; Uryu, Mitsuru; Yamazaki, Toshihiko; Kirita, Fumio; Mashimo, Mitsugu*

no journal, , 

no abstracts in English

Evaluation of long-period ground motion in northern Ibaraki coastal areas on earthquake occurred in the border of Fukushima-Ibaraki prefectures, 1

Yasuda, Masahiro; Uryu, Mitsuru; Yamazaki, Toshihiko; Kirita, Fumio; Fujihara, Satoru*; Kawaji, Kaoru*

no journal, , 

no abstracts in English

Evaluation of long-period ground motion generated from intraplate earthquakes around Ibaraki and Fukushima prefectures

Fujihara, Satoru*; Kirita, Fumio; Kawaji, Kaoru*; Yamazaki, Toshihiko; Uryu, Mitsuru; Yasuda, Masahiro

no journal, , 

no abstracts in English