• Journal of the Korean earth science society
• /
• v.39 no.6
• /
• pp.575-592
• /
• 2018

This study investigates the formation mechanism of columnar joints at the Sanin Kaigan Geopark in Japan based on its morphology, rock type and igneous structure. Columnar joints distribute to five areas of three prefectures. That is, Kyogasaki, Byobuiwa, Tateiwa and Kyugenkado in Kyotango area of Kyoto prefecture; Genbudo and Kinumaki Shrine in Toyooka City of Hyogo prefecture; Yoroinosode, Takanosushima, Mini-Yoroinosode in Kamicho Town of Hyogo prefecture; Miooshima and Nagasakihana, Shitaara Domon, Kuzakuishi, Moroyose dyke in Shinonsencho Town of Hyogo prefecture; Shirawara dyke in Iwamicho Town in Tottori prefecture. Igneous structures are divided into three types: lava flow, sill and dyke. Lithologies are divided into five types including basalt, andesite, dacite, rhyolite, and quartz porphyry. Lava flow shows colonnade and entablature. However, entablature is not seen in the sills and dykes in the area. Although the polygons of columnar joint vary from tetragon to octagon, hexagon is most frequently found. The width of colonnades ranges from 10cm to 1m, but their size does not correlate with its $SiO_2$ contents. Meanwhile, their size and morphology at single site are comparatively uniform.

• Proceedings of the Earthquake Engineering Society of Korea Conference
• /
• 2000.10a
• /
• pp.116-123
• /
• 2000

본 논문은 1995년 일본 남부 효고켄 남부 지진 (코베 대지진)에 의해 코베시에 위치하는 인공섬인 포트 아일랜등서 발생한 액상화 현상을 해석적 기법을 동원하여 액상화 현상의 저감 효과 혹은 방지를 위하여 실시되어져 오고 있는 여러 공법들의 타당성을 수치해석적인 입장에서 검증한 것이다. 따라서, 본 논문에서는 코베시에 의해 획득되어진 연직 방향의 지진 기록에 의해 포트 아일랜드 시공 당시 구역별로 다른 지반 개량 공법을 실시했고, 혹은 실시하지 않는 구역에 대해서 1차원 및 2차원 전응력 그리고 유효 응력 해석 기법을 동원하여 일련의 해석을 실시하였고 그 결과를 다각적인 방향에서 제시하였다.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.7 no.2
• /
• pp.9-20
• /
• 2003

At present, the information on the foundation-structure interaction is lacking. As a result, the seismic performance evaluation of buildings seldom considers the effect of the foundation performance on the building responses. Recent earthquakes such as the 1993 Hokkaido Nansei-oki Earthquake(M=7.8), the 1994 Northridge Earthquake(M=6.7), the 1995 Hyogoken-Nambu Earthquake(M=7.2), and the 1999 Chi-Chi Earthquake (M=7.6) have shown that building damages are significantly affected by the degree of damage sustained by the building foundation and the interaction between the building and the foundation. This paper presents a nonlinear seismic analysis method for the seismic performance evaluation of reinforced concrete buildings which considers the pile foundation-structure interaction. The proposed method is applied to an actual building which was damaged during the 1993 Hokkaido Nansei-oki Earthquake. The result reveal that the method is able to predict the performance of the building.