地铁区间隧道在地面爆炸荷载作用下的数值模拟

Numerical simulation of section subway tunnel under surface explosion

为了考察炸弹在地面爆炸时对地铁区间隧道的影响,应用LS-DYNA软件分析了在地铁上方不同当量装药爆炸时地铁区间隧道的动力响应。模型中考虑了隧道衬砌周围介质中锚杆对介质的锚固作用,得到不同情况下地铁区间隧道的位移、速度及应变时程曲线,并据此进行地面爆炸时地铁区间隧道的安全评估。计算结果表明:地铁区间隧道的顶部和底部中央是比较容易出现破坏的位置,在距离地面1.5 m处100 kgTNT当量炸药爆炸时地铁区间隧道是安全的。

Dynamic responses of section subway tunnel were studied by using LS-DYNA under different yields of surface explosion for evaluation the blast-induced effects. The reinforcement of blot in the surrounding media are taken into consideration in the FEM models. The time histories of displacement, speed and strain of some key points of section subway tunnel were obtained under the different yields, and the safety assessment of subway structures under the surface explosions was completed. The numerical results indicates that the top part and the center at the bottom of the section subway tunnel are more damaged zones, and the section subway tunnel is safe when 100 kg TNT detonates at the height of 1.5 m.