A Case Study on Elephant Foot Method for Railway Tunneling in Large Fault Zone

대규모 단층대구간에서의 철도터널 우각부 보강공법 적용성 연구

  • 이길용 ((주)선진엔지니어링 철도본부) ;
  • 오정호 (한국교통대학교 철도인프라시스템공학과) ;
  • 조계환 ((주)케이알티씨 지반공학부) ;
  • 이두수 ((주)케이알티씨 지반공학부)
  • Received : 2016.07.07
  • Accepted : 2016.09.06
  • Published : 2016.12.01


In this study, an attempt was made to conduct a case study on the development of ground expansive displacement due to lack of bearing capacity of original ground in spite of applying reinforcement treatments that intended to enhance the stability of big size high-speed rail tunnel in large fault zone. For the purpose of this, in-situ measurements made in the middle of excavation stage were analyzed in order to characterize ground responses and numerical analysis was performed to evaluate the effectiveness of reinforcement technique such as elephant foot method applied for this site via comparing with field monitoring measurements. In addition, further numerical studies were carried out to investigate the influence of leg pile installation angle and length, which is one of types of elephant foot method. The results revealed that the optimum condition for the leg pile installation is to maintain 45 degree of installation angle along with 6 meter of embedment depth.


Supported by : 한국교통대학교


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