Effect of Microwave Irradiation on Mechanical Properties and Pick Cutting Performance of Pocheon Granite

Minseong Park; Minseok Ju; Gyeong-Min Ki; Hyunsik Kim; Hoyoung Jeong

doi:10.7474/TUS.2026.36.4.362

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2026 Vol.36, Issue 4 Preview Page Next Page

Original Article

Effect of Microwave Irradiation on Mechanical Properties and Pick Cutting Performance of Pocheon Granite 마이크로웨이브 조사에 따른 포천화강암의 역학적 물성 변화 및 픽커터 절삭 성능 평가

31 August 2026. pp. 362-379

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Abstract

Mechanical excavation is widely used in hard rock excavation because it enables continuous excavation while reducing vibration, noise, and overbreak compared with conventional drilling and blasting. However, in high-strength rocks such as granite, excavation efficiency is often reduced because of high cutting resistance and severe cutter wear. Accordingly, microwave pretreatment has attracted considerable attention as a promising technique for weakening hard rock prior to mechanical excavation. Microwave irradiation induces localized heating and differential thermal expansion among constituent minerals, generating microcracks that degrade the mechanical properties of the rock and improve its cuttability. This study quantitatively investigated the influence of microwave irradiation on the mechanical properties and cutting performance of Pocheon granite. The experimental results showed that microwave irradiation reduced the elastic wave velocities by 23.2% for P-waves and 16.1% for S-waves. The mechanical strength also decreased, with reductions of 35.2% in Brazilian tensile strength and 25.5% in uniaxial compressive strength. In addition, the cutting force and specific energy decreased, while the proportion of fine rock fragments increased. Microwave irradiation significantly reduced the mechanical strength, cutting force, and specific energy while promoting finer fragmentation, demonstrating its potential as a pretreatment technique for improving the efficiency of hard-rock mechanical excavation.

Keywords

Pick cutter

LCM test

Cutting force

Microwave irradiation

기계식 굴착은 발파 굴착에 비해 진동, 소음 및 여굴을 저감할 수 있으며 연속 굴착이 가능하다는 장점을 가진다. 화강암과 같은 고강도 경암 조건에서는 높은 절삭하중과 커터 마모로 인해 굴착 효율이 저하되는 문제가 발생한다. 이에 따라 암석 내부에 열적 손상을 유도하여 절삭저항을 감소시키는 마이크로웨이브 전처리 기술이 경암 굴착의 유망한 보조 공법으로 주목받고 있다. 마이크로웨이브 조사는 암석 내부의 국부적 온도 상승과 광물 간 열팽창 차이에 의해 미세균열을 발생시킬 수 있으며, 이는 암석의 역학적 물성 저하와 절삭 효율 향상으로 이어질 수 있다. 본 연구에서는 국내 포천 화강암을 대상으로 마이크로웨이브 조사에 따른 역학적 물성 변화와 절삭성능 변화를 정량적으로 평가하였다. 이를 위해 탄성파 속도, 일축압축강도 및 간접인장강도를 측정하였으며, 픽 커터를 이용한 선형절삭시험을 통해 절삭력, 수직력, 비에너지 및 파쇄물 입도분포의 변화를 분석하였다. 시험 결과, 마이크로웨이브 조사에 따라 탄성파 속도는 P파는 23.2%, S파는 16.1% 감소하였고, 역학적 강도의 경우 간접인장강도는 35,2%, 일축압축강도 25.5% 감소하였으며, 절삭력과 비에너지는 감소하고 세립 파쇄물의 비율이 증가하였다. 이러한 결과는 마이크로웨이브 전처리가 경암 굴착 시 절삭저항을 감소시키고 절삭효율을 향상시킬 수 있는 효과적인 보조 공법이 될 수 있음을 시사한다.

키워드

픽커터

선형절삭시험

절삭하중

마이크로웨이브 조사

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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 : 36
No :4
Pages :362-379
Received Date : 2026-07-20
Revised Date : 2026-07-31
Accepted Date : 2026-08-10
DOI :https://doi.org/10.7474/TUS.2026.36.4.362

Tunnel and Underground SpaceISSN:1225-1275(Print) 2287-1748(Online)한국암반공학회

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