Considerations in the Estimation of Rock Mass Strength by Measured Displacement-Based Inverse Analysis

Dohyun Park

doi:10.32390/ksmer.2019.56.3.270

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2019 Vol.56, Issue 3 Preview Page Next Page

Research Paper

Considerations in the Estimation of Rock Mass Strength by Measured Displacement-Based Inverse Analysis 계측변위 기반의 역해석에 의한 암반강도 추정 시 고려사항

30 June 2019. pp. 270-279

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Abstract

To ensure construction safety, field measurements in the underground excavation are conducted to investigate possible differences between the ground behavior predicted in the design phase and that observed during construction. When there is a significant difference between these two, a reexamination of the adequacy of excavation design is needed. In this reexamination, the properties of the rock mass should be updated to simulate the ground behavior observed in the field. Inverse analysis can be used as an alternative to field and laboratory tests for determining the properties of the surrounding rock masses. Based on excavation examples applying the Mohr-Coulomb plasticity model, we identified strength parameters of the surrounding rock by ground displacement-based inverse analysis. These applications showed different identification results of the strength parameters, which were dependent on the input displacement conditions. Using these results, we described considerations on the parameter estimation of rock mass strength by ground displacement-based inverse analysis.

Keywords

Inverse analysis

Parameter estimation

Rock mass strength

Field measurement

지하굴착 공사에서 현장계측은 설계단계에서 예측된 지반거동과 시공단계에서 관측된 지반거동의 차이를 조사하고 이로부터 굴착공사의 안전을 확보하기 위해 수행된다. 설계단계와 시공단계의 지반거동이 크게 상이한 경우에는 굴착설계의 적정성을 재검토할 필요가 있다. 이를 위해 현장의 암반거동을 모사할 수 있는 재료물성이 재산정되어야 하며, 주변암반의 물성을 파악하기 위한 현장 및 실내시험에 대한 대안으로서 역해석 기법이 활용될 수 있다. 본 연구에서는 Mohr-Coulomb 탄소성 재료모델을 적용한 굴착예제에 대해 지반변위 기반의 역해석을 적용하여 주변암반의 강도 매개변수를 추정하였다. 계측된 입력변위 조건에 따라 강도 매개변수 추정결과가 다르게 나타났고 이를 토대로 지반변위 기반의 역해석에 의한 암반강도 추정 시 고려사항에 대해 기술하였다.

키워드

역해석

매개변수 추정

암반강도

현장계측

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Information

Publisher :The Korean Society of Mineral and Energy Resources Engineers
Publisher(Ko) :한국자원공학회
Journal Title :Journal of the Korean Society of Mineral and Energy Resources Engineers
Journal Title(Ko) :한국자원공학회지
Volume : 56
No :3
Pages :270-279
Received Date : 2019-06-03
Revised Date : 2019-06-20
Accepted Date : 2019-06-21
DOI :https://doi.org/10.32390/ksmer.2019.56.3.270

Journal of the Korean Society of Mineral and Energy Resources Engineers ISSN:2288-0291(Print) 2288-2790(Online) 한국자원공학회지

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