LONG-TERM CONDITION MONITORING OF A SRC BUILDING BEFORE AND AFTER THE 2011 OFF THE PACIFIC COAST OF TOHOKU EARTHQUAKE

• MORITA Koichi

  National Institute for Land and Infrastructure Management

• KASHIMA Toshihide

  Building Research Institute

• HAMAMOTO Takuji

  Tokyo City University

Bibliographic Information

Other Title

• 東北地方太平洋沖地震前後のSRC造建築物の長期状態モニタリング
• トウホク チホウ タイヘイヨウオキ ジシン ゼンゴ ノ S RCズクリ ケンチクブツ ノ チョウキ ジョウタイ モニタリング

Abstract

 In this study, we identified superstructure stiffness and sway/rocking stiffness using seismic observation data for an eight-story steel-encased reinforced concrete building for which continuous seismic observation had been made since the completion of construction. We analyzed the structural aging and amplitude dependence of superstructure stiffness and sway/rocking stiffness.<br> The target building is the Research Center for Disaster Risk Management of the National Institute for Land and Infrastructure Management (completed in March 1998). Accelerometers on the nearby surface ground, the first basement level, the first floor, the second floor, the fifth floor, and the eighth floor are utilized for the identification.<br> Following three types of natural frequencies with consideration of the influence of the interaction were determined:<br> 1) Combined system, including horizontal motion and rotational motion of the foundation: Natural frequency of SRB type; f_SRB<br> (Input: Acceleration of the ground surface 20 m away from the building)<br> 2) Upper deformation + rotational motion: Natural frequency of RB type; f_RB<br> (Input: Acceleration of the first basement level)<br> 3) Fixed-base system of building deformation only: Natural frequency of B type; f_B<br> (Input: Acceleration of the first basement level + rotational motion of the foundation)<br> These tree-type natural frequencies tend to decrease due to aging and dropped down after the 2011 off the pacific coast of Tohoku earthquake.<br> By using these three natural frequencies, sway/rocking stiffness is estimated. The rocking stiffness tends to increase due to aging, and after Tohoku earthquake sway/rocking stiffness decreases. In large-PGA cases, the sway/rocking stiffness tends to be smaller. Minimum identified values are a little larger than values calculated from soil investigation data.<br> Superstructure stiffness is identified by using natural frequency and participation function. Superstructure stiffness tends to decrease due to aging and dropped down after the 2011 off the pacific coast of Tohoku earthquake. By comparing the identified superstructure stiffness after the 2011 off the pacific coast of Tohoku earthquake and the stiffness from push-over analysis, structure should be between crack point and yielding point. Decreasing rate of lower story stiffness is a little bit larger than that of upper story stiffness. This tendency is same as the results by visual inspection.

Journal

• Journal of Structural and Construction Engineering (Transactions of AIJ)

  Journal of Structural and Construction Engineering (Transactions of AIJ) 81 (730), 2037-2044, 2016

  Architectural Institute of Japan

Keywords

• Long-term condition monitoring
• Strong motion observation
• System identification
• Soil-structure interaction
• Sway-rocking model
• Accumulative damage

Details

• CRID: 1390001205604089984
• NII Article ID: 130006964588
• NII Article ID: 200000365885
• NII Book ID: AN10438559
• DOI: 10.3130/aijs.81.2037
• ISSN: 18818153
• ISSN: 13404202
• NDL BIB ID: 027780497
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I027780497
• Web Site: https://www.jstage.jst.go.jp/article/aijs/81/730/81_2037/_pdf
• Text Lang: ja
• Data Source:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed