Seismic instrumentation for the observation of strong motion in the free-field

• Mikami Atsushi

  徳島大学，工学部建設工学科

• Kamiyama Makoto

  東北工業大学，工学部環境情報工学科

• Sawada Tsutomu

  徳島大学，工学部建設工学科

• Matsuda Toshikazu

  徳島大学大学院

Bibliographic Information

Other Title

• 自由地盤の強震観測に及ぼす地震計設置台座の影響

Abstract

This paper discusses the seismic instrumentation for the strong motion observation in the free-field. A seismometer for the free-field observation is usually mounted on a concrete block whose motion deviates from that of the free-field ground since the block has a different level of stiffness and mass from the soil. Thus, the seismometer mounted on the concrete block may not correctly observe the free-field motion. We computed the concrete block / free-field motion transfer function in the frequency domain for various possible configurations of the block. The results indicate that the instrumentation on the concrete block provides reasonable free-field motion as long as the block is totally embedded and the embedment depth is less than 1 meter. If a portion of the concrete block projects above the ground surface, the portion will contribute to the rocking motion of the block, thus, the portion should be small in dimension and as light-weight as possible.

Journal

• Journal of Structural Engineering, A

  Journal of Structural Engineering, A 53A 321-328, 2007

  Japan Society of Civil Engineers

Keywords

• Instrumentation of seismometer
• free-field motion observation

Details

• CRID: 1390001205282771712
• NII Article ID: 130004503478
• DOI: 10.11532/structcivil.53a.321
• ISSN: 1881820X
• Data Source:
  • JaLC
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed