Analysis of the mechanisms of slope failures triggered by the 2007 Chuetsu Oki earthquake |
| |
| Authors: | Ivan B Gratchev Ikuo Towhata |
| |
| Institution: | (1) School of Engineering, Griffith University, Gold Coast Campus, Gold Coast, QLD, 4222, Australia;(2) Department of Civil Engineering, The University of Tokyo, Tokyo, Japan |
| |
| Abstract: | The 2007 Chuetsu Oki earthquake (MJMA = 6.6) triggered more than one hundred slope failures in the northwest part of Niigata prefecture, Japan. A reconnaissance
survey conducted by the authors revealed that although most of the failures were only a few meters deep, they still caused
significant damage to roads, railways, and houses. It was also found that a vast number of shallow slides were concentrated
along the coastal line of the Japan Sea, while only few, but relatively larger failures occurred in a mountainous part of
the study area, which is located in a considerable distance from the earthquake’s epicenter. This paper summarizes the reconnaissance
observations, describes the geologic characteristics of the area covered by landslides, provides characterization of major
types of the landslides, and examines the causes and mechanisms of typical failures. In addition, this paper seeks to investigate
the mechanism of the Ohzumi landslide, the largest slide triggered by the Chuetsu Oki earthquake. For this purpose, a comprehensive
analysis that included field investigation and laboratory testing of soils samples was performed. Results of field investigation
suggested that the failure plane of the Ohzumi landslide formed in a saturated layer of sandy soil near a boundary with bedrock.
Data from undrained cyclic loading triaxial compression tests indicated that the sandy material was highly susceptible to
generation of high excess pore-water pressures during earthquake loading. On the basis of the obtained results and the outcome
of seismic response and slope stability analyses, the authors posited an explanation on the mechanism of the Ohzumi landslide. |
| |
| Keywords: | |
| 本文献已被 SpringerLink 等数据库收录！ |
|
