Application of Rotary Cutting Test for Performance Assessment of Tunnel Boring Extender

Hoyoung Jeong; Seokwon Jeon; Jung-Woo Cho

doi:10.7474/TUS.2022.32.4.243

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2022 Vol.32, Issue 4 Next Page

Technical Note

Application of Rotary Cutting Test for Performance Assessment of Tunnel Boring Extender TBE의 굴착성능 평가를 위한 회전식 절삭시험의 적용

31 August 2022. pp. 243-253

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Abstract

In this study, the cutting efficiency of TBE (Tunnel Boring Extender) was evaluated by using rotary cutting tester. In the rotary cutting test, a specimen which has a drilled hollow hole at the center was made of rock-like material. The specimen was cut by UDC (undercutting disc cutter) with spiral cutting path to simulate the cutting process of TBE. The cutting forces and specific energy were evaluated under different cutting conditions. The results indicated that the cutter forces of UDC linearly increased with the vertical and radial penetration depths. Among the three directional cutter forces, the normal force is larger than other force components. While the specific energy decreased with the two penetration depths, in particular, it was presumed that the specific energy was minimized at a certain value of the ratio of radial to vertical penetration depth.

Keywords

Rotary cutting test

TBE (Tunnel Boring Extender)

Undercutting

Cutting efficiency

본 연구에서는 회전식 절삭시험기를 활용하여 TBE (Tunnel Boring Extender)의 굴착효율을 평가하였다. 회전식절삭시험에서 TBE에 의한 굴착과정을 모사하기 위하여 중앙부가 선행 굴착되어 있는 중공형의 암석모사시험체를 모르타르를 이용하여 제작하였다. 회전식 절삭시험기에 설치된 언더커팅 디스크(undercutting disc cutter, UDC)를 이용하여 나선궤적을 따라 암석을 절삭함으로써 TBE에 의한 굴착과정을 모사하였으며, 언더커팅 디스크의 절삭조건을 변화시켜가며 절삭조건들이 커터작용력 및 비에너지에 미치는 영향을 살펴보았다. 시험결과로부터 UDC의 커터작용력은 반경압입깊이와 수직압입깊이가 증가함에 따라 선형적으로 증가하는 경향을 확인할 수 있었으며, 세 방향의 작용력 중 수직력의 비중이 매우 크게 나타났다. 반면 비에너지는 반경방향과 수직방향 압입깊이에 따라 지속적으로 감소하는 경향을 나타내었고, 특히 두 압입깊이의 비에 따라 비에너지가 최소화되는 지점이 나타날 것으로 판단되었다.

키워드

회전식 절삭시험

TBE (Tunnel Boring Extender)

언더커팅

절삭효율

References

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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 : 32
No :4
Pages :243-253
Received Date : 2022-08-10
Revised Date : 2022-08-16
Accepted Date : 2022-08-16
DOI :https://doi.org/10.7474/TUS.2022.32.4.243

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

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