Journal of the Korean Geosynthetics Society (한국지반신소재학회논문집)

Korean Geosynthetics Society (한국지반신소재학회)
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A Study on Stabilization of the Collapsed Slope due to Gyeongju Earthquake at Seokguram Access Road based on Geological Investigation

지질학적 조사를 바탕으로 한 경주지진으로 붕괴된 석굴암 진입도로 비탈면의 안정성 평가에 관한 연구

  • Kim, Seung-Hyun (Integrated Road Management Research Center, Korea Institute of Civil engineering & building Technology) ;
  • Lee, Kwang-Wu (Department of Infrastructure Safety Research, Korea Institute of Civil engineering & building Technology)
  • Received : 2019.12.03
  • Accepted : 2019.12.17
  • Published : 2019.12.30
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Abstract

Rockfall failure at the access road to Seokguram were occurred due to the earthquake on September 12, 2016. A detailed investigation was carried out in order to find out the cause of the rockfall, to identify the risk of the entire sites, and to prepare proper countermeasure methods and mitigation. We checked for geological and topographical characteristics of overall slopes alongside the access road to Seokguram and made a face map. In addition, we analyzed topographical factors caused by the earthquake through calculating a degree of slope, degree of bearing, upslope contributing area, and wetness index with the use of shading relief map. As a result, we confirmed that the large rockfall occurred with a weak section. In this study, we also evaluated the overall slope stability of the entire access road to Seokguram in order to classify it into danger and caution zones depending on the risk of collapse.

2016년 9월 12일 발생한 경주지진의 영향으로 석굴암 진입도로 구간 내 대형낙석이 발생되었다. 낙석의 발생 원인 규명과 진입도로 전체 구간의 비탈면 위험성을 확인하고, 적정한 대책방안을 마련하기 위한 정밀조사가 실시되었다. 석굴암 진입도로 주변의 지형 및 지질 특성 확인, 현황도 작성을 통한 특성 파악 등을 바탕으로 구간별 위험도를 위험, 주의, 안정으로 분류하였다. 또한 음영기복도를 활용하여 경사도, 방위도, 상부사면기여면적, 습윤지수 등을 도출함으로써, 지진 발생으로 인한 위험 구간과 지형적 요인의 특성에 대하여 고찰하였고, 이를 통해 대형낙석 발생 구간이 취약 구간이었음을 확인할 수 있었다. 본 연구를 통해 석굴암 진입도로 전반에 대한 비탈면 안정 상태를 평가하여, 붕괴 위험정도에 따라 위험구간과 주의구간으로 분류함으로써, 석굴암 진입도로 주변의 산사태 관리를 위한 기반을 마련하였다.

Keywords

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