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

Hoyoung Jeong; Hanam Son; Suhan Kim; Yeolwoo Kim

doi:10.7474/TUS.2021.31.6.578

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2021 Vol.31, Issue 6 Preview Page Next Page

Original Article

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

31 December 2021. pp. 578-592

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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.

Keywords

Underwater blasting

Mesh size

Overpressure

Impulse

Peak Particle Velocity (PPV)

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.

키워드

수중발파

메쉬크기

과압

충격량

최대입자속도

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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 :578-592
Received Date : 2021-12-07
Revised Date : 2021-12-13
Accepted Date : 2021-12-13
DOI :https://doi.org/10.7474/TUS.2021.31.6.578

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

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