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Comparison of advance rate and powder factor of two- and three-free-face blasting

2, 3 자유면 발파의 굴진율 및 비장약량 비교

  • Youngmin Yoon (Dept. of Energy Systems Engineering, Seoul National University) ;
  • Seokwon Jeon (Dept. of Energy Systems Engineering, Seoul National University)
  • 윤영민 (서울대학교 에너지시스템공학부) ;
  • 전석원 (서울대학교 에너지시스템공학부)
  • Received : 2024.05.31
  • Accepted : 2024.09.20
  • Published : 2024.09.30

Abstract

Advance rate significantly affects both the construction period and cost in tunnel blasting. As such, there has been persistent research dedicated to the development of innovative blasting technique aimed at enhancing the advance rate. This paper aims to provide fundamental insights into the differences in advance rate and the powder factor between two- and three-free-face blasting, laying the groundwork for the advancement of tunnel blasting techniques. Large-scale cement mortar specimens were fabricated, and blasting tests were conducted for both two- and three-free-face blasting. Experimental findings were then compared with those from numerical simulation. Notably, an increase in the number of free faces, under uniform conditions, significantly improved the advance rate while reducing the powder factor. The outcomes of this study serve as crucial groundwork for devising blasting patterns employing three-free-face blasting, characterized by improved advance rates and minimized powder factors. Consequently, the anticipated outcomes include an overall improvement in tunnel advance rates and a reduction in the number of drilling holes and the amounts of explosives.

터널 발파에서 굴진율은 공사기간과 공사비에 영향을 미치는 중요한 요소이므로 굴진율 증대를 위한 발파공법개발 연구가 계속해서 이루어지고 있다. 본 논문에서는 굴진율 증대를 위한 새로운 발파패턴 개발을 위한 기초자료 확보를 목적으로 2, 3 자유면 발파의 굴진율과 비장약량의 차이를 비교하고자 하였다. 대형 시멘트 모르타르 시험체를 제작하여 2, 3 자유면 발파실험을 수행하고, 실험 결과를 수치해석 결과와 비교하였다. 동일 조건하에서 2자유면 발파보다 3자유면 발파 시 귤진율이 크게 증가하였고, 비장약량은 감소하였다. 본 연구의 결과는 3자유면을 활용한 발파패턴 개발에 활용될 것이며, 이를 통한 터널 및 노천 발파에 있어서의 굴진율 증대 및 천공 수와 화약량 감소 효과를 기대한다.

Keywords

Acknowledgement

본 연구는 2021년도 정부(산업통상자원부)의 재원으로 해외자원개발협회의 지원을 받아 수행되었습니다(2021060003, 스마트 마이닝 전문 인력 양성). 이에 감사드립니다.

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