爆破荷载作用下邻近深埋隧道衬砌动力响应数值模拟

Numerical simulation of dynamic response of deep buried tunnel lining under adjacent blasting load

为了研究深埋小净距隧道在爆破荷载下的动力响应以及保证隧道的安全和稳定,以三洞分离隧道爆破开挖工程为背景,通过ANSYS/LS-DYNA模拟分析深埋小净距隧道在爆破荷载作用下的衬砌动力响应。分析了隧道同一截面拱顶、拱腰、拱脚不同测点,不同断面的振速和位移。研究结果表明:衬砌内侧(与净空面接触)拱脚首先产生振动,爆破卸载后,衬砌外侧(与岩石接触)振动速度达到峰值。纵断面的振动速度差异较大,水平位移的影响大于垂向位移的影响。最大位移出现在拱顶,其次出现在迎爆侧拱腰处。断面拱脚处测点振动加速度最大,受到的爆轰也最大。

In order to study the dynamic response of the deep buried tunnel with small net distance under blasting load and ensure the safety and stability of the tunnel,under the background of three-hole separation tunnel blasting excavation,ANSYS/LS-DYNA was used to analyze the dynamic response of deep-buried tunnel with small net distance.The vibration velocity and displacement of the same section of the tunnel are analyzed at different measuring points of the vault,arch waist and arch foot.The results show that the inner arch foot of the lining(the side in contact with the free surface)vibrates first,and the vibration velocity of the outer lining(the side in contact with the rock)reaches the peak after blasting discharge.There is great difference in vibration velocity at longitudinal section.The effect of horizontal displacement is greater than that of vertical displacement.The maximum displacement occurs at the arch top,followed by the side arch waist on the side facing the explosion.The vibration acceleration of the measuring point at the arch foot of the section is the largest and the detonation is also the largest.