爆破冲击波在隧道变截面断面的传播特性
Propagation Characteristics of Blasting Shock Wave in Variable Cross Section of Tunnel
冯建平 1王耀华 2满军 3豆留盼 2方勇 2方晓峰2
作者信息
- 1. 中铁城市发展投资集团有限公司,成都 610218
- 2. 西南交通大学土木工程学院,成都 610031
- 3. 中铁二局第六工程有限公司,成都 610014
- 折叠
摘要
为研究爆破冲击波在隧道内复杂环境下的传播规律,以老营盘隧道为依托,通过建立三维数值模型,在LS-DYNA软件中分析了隧道断面变化不同系数下冲击波的传播规律.研究结果表明:冲击波经过变截面后,总体上以平面波的形式向前传播;冲击波传播至隧道断面扩大界面时,冲击波超压衰减速度加快,超压峰值降低;当断面扩大1.5倍时,冲击波冲量衰减系数为1.158,冲击波能量残留比率为74.5％;断面扩大倍数越大,冲击波超压衰减速度越大,能量衰减幅度越大;冲击波传播至隧道断面缩小界面时,冲击波超压增大,其衰减速度减缓,导致冲击波造成的损伤程度增加;当断面缩小系数取0.5时,冲击波冲量增强系数为0.687,冲击波能量放大系数为2.122;断面缩小系数越小,冲击波造成的损伤越大.
Abstract
In order to study the propagation law of blasting shock wave in the complex environment of tunnel,based on Laoyingpan tunnel,the propagation law of shock wave under different coefficients of tunnel section change was analyzed in LS-DYNA software by establishing a three-dimensional numerical model.The results show that after the shock wave passes through the variable cross section,it generally propagates in the form of plane wave.When the shock wave propagates to the enlarged interface of the tunnel section,the attenuation speed of the shock wave overpressure is accelerated and the overpressure peak is reduced.When the section is enlarged by 1.5 times,the attenuation coefficient of shock wave impulse is 1.158,and the residual ratio of shock wave energy is 74.5％.The larger the expansion ratio of the cross section,the greater the attenuation speed of the shock wave overpressure and the greater the energy attenuation amplitude.When the shock wave propagates to the reduced interface of the tunnel section,the overpressure of the shock wave increases,and its attenuation rate slows down,resulting in an increase in the degree of damage caused by the shock wave.When the section reduction coefficient is 0.5,the shock wave impulse enhancement coefficient is 0.687,and the shock wave energy amplification coefficient is 2.122.The smaller the reduction coefficient of the section,the greater the damage caused by the shock wave.
关键词
公路隧道/冲击波/变截面/传播规律Key words
highway tunnels/shock wave/variable cross-section/laws of transmission引用本文复制引用
出版年
2024
NETL
NSTL
万方数据