机场跑道下部隧道爆破施工的合理埋深研究

以正在规划中的重庆轨道交通轻轨三号线下穿重庆江北机场主跑道及滑行道的区段为研究背景,采用ANSYS/LS-DYNA动力有限元软件对不同埋深的隧道掘进爆破施工进行数值模拟,通过对地表爆破振速与埋深的关系的分析研究,得出隧道施工的合理埋深。模拟计算的结果显示:软件中的高性能炸药材料MAT_HIGH_EXPLOSIVE_BURN的模型能较好模拟爆炸荷载,模拟计算得出的地表最大振动速度与实测最大振速相近;地表震动响应随着隧道埋深的增加而减小;地表振动速度与爆破装药量近似呈正比例关系。结合机场跑道安全标准,确定了机场跑道下部的隧道爆破施工的合理埋深。

Study on Rational Blasting Depth of Tunnel Passing under through Airport Runway

Based on the Chongqing light rail line 3 project under planning, in which a tunnel will pass under through the Jiangbei airport runway, the excavation blasting for tunnel with different buried depths has been simulated numerically by dynamic finite element software ANSYS/LS-DYNA, and the relationship between ground vibration velocity and the tunnel buried depth is analyzed through the simulated results. The simulated results show that the model MAT_HIGH_ EXPLOSIVE_BURN for the blasting material simulated the blasting load well, and the obtained maximum vertical velocity is rational; the vibration response of ground decreases with the increasing buried depth and the vibration velocity of ground is fairly in direct proportion to explosive charge. The rational buried depth of the tunnel under the runway of airfield is set according to the safety standards of the runway.