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2020 Vol.30, Issue 1

Research Article

A Study on the Suitability of the Mohr-Coulomb Model for Numerical Analysis of Ground Excavation

지반굴착 시 Mohr-Coulomb 모델 적합성에 관한 수치해석적 분석

Jonghyun Lee1*
,
Hyunsik Jin2
,
Joonsang An3
,
Yong Baek4
,
Hyeongsuk Yoon5
이 종현1*
,
진 현식2
,
안 준상3
,
백 용4
,
윤 형석5
1Senior Researcher, Multi Disaster Countermeasures Organization, Korea Institute of Civil Engineering and Building Technology
2CEO, HNG Consultants Co., Ltd.
3CEO, BasisSoft, Inc.
4Research Fellow, Multi Disaster Countermeasures Organization, Korea Institute of Civil Engineering and Building Technology
5Professor, Department of Civil & Environmental Technology, Inha Technical College
1한국건설기술연구원 복합재난대응연구단 수석연구원
2(주)HNG컨설턴트 대표
3(주)베이시스소프트 대표
4한국건설기술연구원 복합재난대응연구단 연구위원
5인하공업전문대학 토목환경과 교수
*Corresponding Author
31 March 2020. pp. 1-15
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Abstract

The Mohr-Coulomb model is mainly used in evaluating the behavior of the ground in numerical analyses of domestic ground excavation. This study analyzes its limitations and compares its numerical results with the hyperbolic model, a model that closely follows actual ground behavior during excavation. Recent applications of the Mohr-Coulomb model in Korea have tended to impose arbitrary special boundary conditions to control the problem of excessive heaving of the ground excavation surface. This adjustment only controls the size of the heaving of the excavation surface, implying that the ground behavior is distorted from the actual behavior. This study compares results from the hyperbolic model (hardening soil model) and the Mohr-Coulomb model, and confirms that the hyperbolic model provides both a more-suitable solution to the problem of heaving during excavation and the actual stress-strain behavior. In numerical analyses of ground excavation, the hyperbolic model is expected to give results consistent with the actual ground behavior.

Keywords
ground excavation
heaving
hyperbolic model
numerical analysis

본 연구에서는 국내 지반굴착에 의한 지반거동 수치해석 평가 시 주로 사용되고 있는 Mohr-Coulomb 모델의 한계점을 분석하고, 실제 지반굴착 거동에 잘 부합되는 Hyperbolic 모델과 수치해석 결과를 비교하였다. 최근 국내에서 Mohr-Coulomb 모델 사용 시 지반굴착면이 실제보다 과다하게 융기되는 현상을 제어하기 위해서 특별한 경계조건을 임의대로 부과해서 해결하는 경향이 있다. 이러한 결과는 굴착면의 융기량의 크기만 제어할 뿐 지반거동이 실제와 왜곡되어 나타나는 문제점을 내포하고 있다. 본 연구에서 Hyperbolic 모델(Hardening Soil model)을 사용한 결과와 Mohr-Coulomb 모델을 사용한 결과를 비교하여, Hyperbolic 모델이 굴착 지반 융기량 및 실제 지반의 응력-변형거동에 더 잘 부합됨을 확인하였다. 지반굴착에 관한 수치해석 분석 시 Hyperbolic 모델을 사용하는 것이 실제 지반거동에 부합되는 결과를 얻을 수 있을 것으로 판단된다.

키워드
지반굴착
융기
hyperbolic 모델
수치해석
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Information
  • Publisher :Korean Society of Engineering Geology
  • Publisher(Ko) :대한지질공학회
  • Journal Title :The Journal of Engineering Geology
  • Journal Title(Ko) :지질공학
  • Volume : 30
  • No :1
  • Pages :1-15
  • Received Date : 2020-01-09
  • Accepted Date : 2020-02-05
  • DOI :https://doi.org/10.9720/kseg.2020.1.001
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