A Study on the Correlation between Coal Mining Subsidence and Underground Goaf

페탄광지역의 지반침하발생과 지하 채굴적의 상관관계 연구

  • Choi, Jong-Kuk (Department of Earth System Sciences, Yonsei University) ;
  • Kim, Ki-Dong (Geohazard Information Laboratory, Department of Geoinformation Engineering, Sejong University) ;
  • Song, Kyo-Young (Geological Mapping Group, Korea Institute of Geoscience and Mineral Resources) ;
  • Jo, Min-Jeong (Department of Earth System Sciences, Yonsei University)
  • 최종국 (연세대학교 지구시스템과학과) ;
  • 김기동 (세종대학교 지구정보공학과 지질재해정보연구실) ;
  • 송교영 (한국지질자원연구원 지질도.지구조연구실) ;
  • 조민정 (연세대학교 지구시스템과학과)
  • Published : 2008.08.28

Abstract

This study is to examine a relation between coal mining subsidence occurrence at abandoned underground coal mines and underground goaf with respect to surface geology, subsurface structure, depth and thickness of coal beds and the distribution of drifts. A study is carried out at the site where susceptibility of coal mining subsidence was proven high in a previous study. In that previous study, the susceptibility of coal mining subsidence was spatially analyzed by GIS using digitized geological maps, investigation reports, digitized mining tunnel maps without consideration of subsurface structure and the multi-level arrangement of drifts. Here we analyze geological characteristics around the goaf and the distribution of coal seam based upon digitized geological maps and investigation reports on the study area. And digitized mining tunnel maps are also used to analyze the depth and multi-level arrangement of drifts. The results show that weakened surface rock strength, relatively shallow depth and large thickness of coal seam below the surface are closely related to the coal mining subsidence occurrence. Complicatedly inter-connected drifts, shallow depth of drifts and surface rock fractures are revealed as additional control factors affecting coal mining subsidence. These factors examined in this study as well as original factors should be taken into account for the quantitative estimation of coal mining subsidence occurrence at abandoned underground coal mine.

이 연구에서는 폐탄광 지역에서 발생하는 지반침하와 지하 채굴적 사이의 상관성을 지질, 지하구조, 탄층의 심도와 두께, 지하갱도의 분포 측면에서 분석하고자 하였다. 연구대상 지역은 강원도 삼척시 삼척탄전에 속하며, 채굴적 특성을 고려하지 않은 기존의 연구에서 수치지질도, 수치갱내도, 현장조사보고서 자료와 GIS의 공간분석기법을 적용하여 지반침하 취약성이 높게 분석된 지역에 해당된다. 연구지역에 대한 수치지질도 및 지반안정성 조사 보고서를 기반으로 연구지역내에서 지반침하가 관측된 지역의 분포, 지표 및 지하의 지질구조와 탄층의 분포현황을 분석하였고, 수치갱내도 자료를 이용하여 지하 갱도의 심도 및 중첩분포 현황을 분석하였다. 연구결과, 지표의 암석 강도 저하, 얕은 심도와 두꺼운 층후의 함탄층 존재가 지반침하 발생과 밀접한 관련이 있는 것으로 분석되었다. 또한, 다수의 중첩된 갱도의 분포 및 얕은 심도의 지하 갱도 존재, 단층의 존재 역시 지반침하발생에 영향을 주는 주요인으로 확인되었다. 지반침하 위험지역을 정량적으로 예측함에 있어, 연구결과로 나타난 지반침하 관련 요인을 추가로 데이터베이스화하여 폐탄광 지역별로 적합한 지반침하예측 모델을 구축한다면 폐탄광 지역의 지반침하위험 예측 및 예방에 매우 효과적일 것으로 판단된다.

Keywords

References

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