爆炸荷载作用下地铁隧道的冲击反应研究

随着地铁的大规模兴建，地铁隧道的抗爆防护研究成为一个迫切需要解决的问题。针对南京地铁区间隧道的实际工程地质条件，建立了地铁隧道的冲击反应计算模型和各种材料的模型，采用流固耦合算法， 对10kgTNT炸药作用下地铁隧道的冲击反应进行了全面研究。研究结果表明，隧道衬砌的速度和加速度变化与超压有关，随着距爆心距离的增大，爆炸冲击波对衬砌结构的影响逐渐减弱，而且在爆炸的初始时刻，隧道衬砌处于受拉状态，随着时间的推移，超压峰值逐渐衰减，隧道衬砌则由受拉状态变为受压状态，并逐渐趋于稳定，从而为地铁隧道的抗爆防护和应急预案的制定提供了依据。

Shock responses of a metro tunnel subjected to explosive loads

With large-scale construction of metro,the anti-explosion protection of metro tunnels becomes an urgent problem.Aiming at the practical engineering geological conditions of running tunnels in Nanjing metro,a calculation model for shock responses of a metro tunnel was established,and comprehensive study on shock response of a metro tunnel under action of 10kg TNT was conducted with fluid-structure coupling computation.The results indicated that velocity and acceleration variations of the liner are related with overpressure and with increase in the distance from the blasting center,the influence of the explosive shock waves on the liner structure decreases;moreover,at the initial time of the explosion,the liner of the metro is in tensile state,and with time passing,the peak value of the overpressure decreases gradually,then the tensile state of the tunnel liner changes into a compressed one and tends to be stable finally.The results provided a reference for anti-explosion protection of a metro tunnel and making an emergent preplan.