Citation

Kobori T, Yamaguchi Y, Nakashima S, Shimizu N. J. Jpn. Soc. Dam Eng. 2015; 25(1): 6-15.

Vernacular Title

GPSを用いたロックフィルダム堤体の地震時変位挙動計測

Copyright

(Copyright © 2015, Japan Society of Dam Engineers)

DOI

10.11315/jsde.25.6

PMID

unavailable

Abstract

Exterior deformation is one of the most important items to measure when managing the safety of embankment dams. A conventional surveying method, using targets installed on the crest and the slopes of the embankment dams, is usually employed to measure exterior deformation. It is difficult, however, to measure the deformation by such a method immediately after an earthquake or other emergency. A displacement monitoring system using GPS (Global Positioning System) was developed to continuously monitor the deformation of dams. The system can provide three-dimensional displacements at many points simultaneously with high accuracy at the millimeter level. Ishibuchi Dam is a concrete-face rock-fill dam; it is one of the oldest rock-fill dams in Japan. After the large settlement caused by the Iwate-Miyagi Nairiku Earthquake of 2008, the above GPS displacement monitoring system was installed to continuously monitor the deformation behavior. On March 11, 2011, the Great East Japan Earthquake struck near the northeast coast of Honshu Island. This paper describes the results of the deformation monitoring of Ishibuchi Dam before, during, and after the Great East Japan Earthquake, and discusses the validity of the system for the safe management of dams after earthquakes.

Language: ja

Vernacular Abstract

筆者らは，高精度で連続計測が可能なGPSによるダム変位計測システムを開発し，多くのフィルダムに適用してきたが，これまでに大きな地震時におけるダム変位を計測する機会はなかった。東北地方太平洋沖地震の際，石淵ダムに設置していたGPS変位計測システムによって，地震前から地震後にかけて連続的にダム堤体の外部変位を計測することができた。本論文は，石淵ダムにおける地震時の変位計測結果を示すとともに，地震時の計測の即応性および地震によるダムの堤体変位について考察し，GPSによる変位計測の有効性を検証するものである。