Investigation on Shape Effect of Rock Specimens to Uniaxial Compressive Strength and Modification of Performance Prediction Model of a Roadheader

Mun-Gyu Kim; Sang-Min Lee; Jung-Woo Cho; Sung-Hyun Choi; Jun-Won Eom

doi:10.7474/TUS.2021.31.6.440

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2021 Vol.31, Issue 6 Preview Page Next Page

Technical Note

Investigation on Shape Effect of Rock Specimens to Uniaxial Compressive Strength and Modification of Performance Prediction Model of a Roadheader 일축압축강도에 미치는 암석시편의 형상효과 고찰 및 로드헤더 굴진율 예측모델 수정

31 December 2021. pp. 440-459

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Abstract

Roadheaders have begun to be adopted in Korean tunneling sites. The performance prediction models proposed by the manufacturer are used by Korean construction companies. The models use UCS (uniaxial compressive strength) value to predict the net cutting rate, but the rock specimens conducted for the uniaxial compression test have 1.0 of the diameter to length ratio. It has been reported that the specimen shape generally influences the rock strength. The previous references studying the shape effect were cited, and the UCS data of Korean rocks are also updated to analyze the shape effect on UCS. The cause of effect was discussed by previous theory. The change amount of UCS values of Korean rocks was estimated by the data, and the modified prediction model for NCR was finally suggested.

Keywords

Roadheader

Net cutting rate

Uniaxial compressive strength

Performance prediction

Shape effect

Modified prediction model

최근 대형 로드헤더가 국내 터널현장에 도입되면서 해외 제조사의 굴진율 예측모델에 대한 관심이 증가하고 있다. 현재 주로 사용되는 해외모델은 압축강도로부터 굴진율을 예측하고 있는데, 암석 시험편의 직경 대 길이의 비율이 1.0인 시편을 일축압축시험으로 사용하고 있다. 일반적으로 시편의 형상과 치수는 강도에 영향을 미치는 것으로 알려져 있다. 본 기술보고에서는 직경 대 길이 비율에 따른 암석강도의 변화에 대한 기존 연구사례를 조사하였다. 그 형상효과에 대한 원인을 이론적으로 고찰하였다. 이를 토대로 국내 예정된 암종에 대해서 길이 비율에 따른 강도의 변화 양상을 예측하고 굴진율 수정모델을 제시하였다.

키워드

형상효과

일축압축강도

로드헤더

순굴진율

수정 예측모델

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Information

Publisher :Korean Society for Rock Mechanics and Rock Engineering
Publisher(Ko) :한국암반공학회
Journal Title :Tunnel and Underground Space
Journal Title(Ko) :터널과 지하공간
Volume : 31
No :6
Pages :440-459
Received Date : 2021-12-10
Revised Date : 2021-12-16
Accepted Date : 2021-12-17
DOI :https://doi.org/10.7474/TUS.2021.31.6.440

Tunnel and Underground Space ISSN:1225-1275(Print) 2287-1748(Online) 터널과 지하공간

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