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A numerical study on the 3-Dimensional shape characteristics of small underground cavities

소규모 지하공동 3차원 형상 특성을 반영한 수치해석에 관한 연구

  • 안준상 ((주)베이시스소프트 건설IT연구소) ;
  • 강경남 (인하대학교 토목공학과) ;
  • 송기일 (인하대학교 토목공학과) ;
  • 김우석 (한국건설기술연구원 인프라안전연구본부) ;
  • 김병찬 ((주)베이시스소프트 건설IT연구소)
  • Received : 2018.06.20
  • Accepted : 2018.07.31
  • Published : 2018.09.30

Abstract

When conducting the underground safety impact assessment under the special law in Korea, it is essential to investigate the occurrence of underground cavities. When underground cavities were discovered, the underground safety was assessed through numerical analysis. The previous study has suggested the stability evaluation based on the factor of safety by changing the 2D shape of the small underground cavity. In this study, the effects of small underground cavities considering 3D shapes were examined using a continuum analysis program and compared with the 2D results presented in previous study. If the 3-Dimensional shape of the underground cavity is found close to the sphere type, it would be reasonable to evaluate the factor of safety by the shear strength reduction method regardless of the size and position of the cavity. If a high-aspect ratio underground cavity with a depth of 2 m or more from the ground surface and an aspect ratio (a/b) of 2.0 or more is in the vertical direction, not only the factor of safety but the failure mode shape should be cautions in the stability evaluation using the shear strength reduction method. The results of this study are expected to be basic data on underground safety impact assessment.

Acknowledgement

Grant : 지반함몰 발생 및 피해저감을 위한 지반 안정성 평가 및 굴착.보강기술 개발

Supported by : 국토교통과학기술진흥원

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