Tunnel and Underground Space (터널과지하공간)

Korean Society for Rock Mechanics and Rock Engineering (한국암반공학회)
권호 표지
DOI QR코드

DOI QR Code

Numerical Study on Effect of Mesh Size on Vibration and Overpressure Propagation Induced by Underwater Blasting

수중발파로 인한 과압 및 진동 전파에서 메쉬크기의 영향에 대한 수치해석 연구

  • Jeong, Hoyoung (Department of Energy Resources Engineering, Pukyong National University) ;
  • Son, Hanam (Department of Energy Resources Engineering, Pukyong National University) ;
  • Kim, Suhan (Department of Civil Engineering, Pukyong National University) ;
  • Kim, Yeolwoo (Department of Civil Engineering, Pukyong National University)
  • 정호영 (부경대학교 에너지자원공학과) ;
  • 손한암 (부경대학교 에너지자원공학과) ;
  • 김수한 (부경대학교 토목공학과) ;
  • 김열우 (부경대학교 토목공학과)
  • Received : 2021.12.07
  • Accepted : 2021.12.13
  • Published : 2021.12.31
Download PDF
⟨ Previous Next ⟩

Abstract

This study performed to investigate the propagation characteristics of overpressure, impulse, vibration in underwater blasting. The difference between air blasting and underwater blasting is that noise and vibration propagate through water as a medium. In some cases, the noise and vibration propagates through various media (rock, water, air, etc.). In this study, the underwater blasting was simulated using AUTODYN, and the propagation characteristics of overpressure, impulse and vibration induced by blasting were analyzed. We mainly focused on the effect of mesh size on the overpressure, impulse and peak particle velocity from the underwater blasting simulation. The numerical results indicated that the overpressure and peak particle velocity tended to decrease as the mesh size increased, while the impulse increased with the mesh size. The results also indicated that the mesh dependence varied depending on the explosive charge and scaled distance.

본 연구에서는 수중발파에서 발생하는 과압, 충격량, 진동의 전파 특성을 평가하기 위하여 수행되었다. 육상에서의 발파와 비교하여 수중발파에서의 소음 및 진동의 전파 특성은 주로 물을 매개체로 하여 전파되는 차이를 가지고 있으며, 경우에 따라 다양한 매질(암반, 물, 공기 등)을 통과하면서 전파양상이 변화하는 특성도 지니고 있다. 본 연구에서는 AUTODYN을 이용하여 수중에서의 발파과정을 모사하고 발파로부터 생성된 과압, 충격량, 발파진동의 전파 특성에 대하여 분석하였다. 특히 메쉬크기가 수중발파해석으로부터 획득되는 과압, 충격량, 최대입자속도에 미치는 영향을 중점적으로 평가하였다. 전체적으로 과압과 최대입자속도는 메쉬의 크기가 증가함에 따라 감소하는 경향성을 나타내었고, 충격량은 메쉬의 크기와 함께 증가하는 경향을 보였다. 또한 본 연구의 결과로부터 메쉬 크기에 대한 의존성은 장약량과 환산거리에 따라서도 다르게 나타날 수 있다는 것을 확인하였다.

Keywords

Acknowledgement

이 논문은 2021학년도 부경대학교 국립대학육성사업 지원비에 의하여 연구되었음. 또한 2021년도 정부(과학기술정보통신부)의 재원으로 한국연구재단의 지원을 받아 수행된 연구임(No. NRF-2021R1G1A1091572).

References

  1. Chapman, T.C., Rose, T.A. and Smith, P.D., 1995, Blast wave simulation using AUTODYN2D: a parametric study, Int. J. Impact Eng. 16.5-6, 777-787. https://doi.org/10.1016/0734-743X(95)00012-Y
  2. Choi, T.H., Kim, J.H., Song, H.L. and Ko, C.S., 2015, Suggestion of safety level in fish farming by impulsive sound, Tunn. Undergr. Sp. 25.2, 125-132. https://doi.org/10.7474/TUS.2015.25.2.125
  3. Cole, R.H., 1948, Underwater Explosions, Dover Publications, New York, 1948.
  4. Kim, J. and Shin, H., 2008, Application of the ALE technique for underwater explosionanalysis of a submarine liquefied oxygen tank, Ocean Eng. 35, 812.822. https://doi.org/10.1016/j.oceaneng.2008.01.019
  5. Kim, Y.K. and Kim, S.K., 2018, A case of underwater blasting performance using a structural underwater charging system, Explosives and Blasting. 36.2, 27-35. https://doi.org/10.22704/KSEE.2018.36.2.027
  6. Krauthammer, T. and Otani, R.K., 1997, Mesh, gravity and load effects on finite element simulations of blast loaded reinforced concrete structures, Comput. Struct. 63, 1113-1120. https://doi.org/10.1016/S0045-7949(96)00406-3
  7. Lee, E.L., Hornig, H.C. and Kury, J.W., 1968, Adiabatic expansion of high explosives detonation products (Report UCRL 50422), Lawrence Livermore National Laboratory, Livermore, CA, USA.
  8. Lee, S., Kim, S.K. and Lee, Y.H., 2006, Study of blast ground vibration & noise measurements in-situ and effect analysis for numerical anaylsis, rational blasting design at an eel farm, Tunn. Undergr. Sp. 16.2, 179-188.
  9. Luccioni, B., Ambrosini, D. and Danesi, R., 2006, Blast load assessment using hydrocodes, Eng. Struct. 28.12, 1736-1744. https://doi.org/10.1016/j.engstruct.2006.02.016
  10. Park, Y.S., Park, S.J., Kang, S.H.,, Jeon, Y.B. and Gong, G.J., 2006, An experimental study on ground vibration equations by underwater blasting at construction site, Trans. Korean Soc. Noise Vib. 16.7, 777-783. https://doi.org/10.5050/KSNVN.2006.16.7.777
  11. Shi, Y., Li, Z. and Hao, H., 2008, Mesh size effect in numerical simulation of blast wave propagation and interaction with structures, Trans. Tianjin Univ. 14.6, 396-402. https://doi.org/10.1007/s12209-008-0068-9
  12. Wang, G., Wang, Y., Lu, W., Zhou, W., Chen, M. and Yan, P., 2016, On the determination of the mesh size for numerical simulations of shock wave propagation in near field underwater explosion, Appl. Ocean Res. 59, 1-9. https://doi.org/10.1016/j.apor.2016.05.011
  13. Zamyshlyayev, B. and Yakovlev, Y.S., 1973, Dynamic Load in Underwater Explosion, Naval Intelligence Support Center.