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Determination of equivalent elastic modulus of shotcrete-tetragonal lattice girder composite

사변형 격자지보재-숏크리트 합성부재의 등가물성 결정 기법

  • Kang, Kyung-Nam (Dept. of Civil Engineering, Inha University) ;
  • Song, Ki-Il (Dept. of Civil Engineering, Inha University) ;
  • Kim, Sun Gil (Civil Infrastructure Research Division, Kolon Global Corporation) ;
  • Kim, Kyoung Chul (Civil Infrastructure Research Division, Kolon Global Corporation)
  • 강경남 (인하대학교 토목공학과) ;
  • 송기일 (인하대학교 토목공학과) ;
  • 김선길 (코오롱글로벌 기술연구소) ;
  • 김경철 (코오롱글로벌 기술연구소)
  • Received : 2020.01.14
  • Accepted : 2020.03.20
  • Published : 2020.03.31

Abstract

Steel set is a structure that stabilize the NATM tunnel until the installation of shotcrete, and it is combined after the shotcrete is installed to improve stability. In this study, determination approach for the equivalent elastic modulus of shotcrete-lattice girder composite is newly suggested for tunneling simulation. Also, a method was presented to calibrate the equivalent elastic modulus through the comparison of the full 3D model and equivalent model. When the conventional equivalent elastic modulus is used for shotcrete-lattice girder composite, the flexural strength of equivalent model is 130% smaller than that of full 3D model. Equivalent elastic modulus is adjusted considering the error of flexural strength. It is found that the error of flexural strength obtained from adjusted equivalent model using adjusted equivalent elastic modulus is reduced less than 1%.

Acknowledgement

Supported by : 한국연구재단

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