By taking of Hengsanlu tunnel as extension project in Guizhou province, three dimensional modeling was carried out to investigate the influence of explosion-induced impact load on the deformation characteristic, mechanical response and energy concentration of tunnel lining. Inspection of modeling reveals that energy concentration appears at the lining facing the explosion. Most vibration velocities of lining exceed the requirement of code, i.e., safety regulations for blasting in China. Explosion would lead to local damage of lining, rather than large zone collapse. Shear-damage appears in the explosion zone lining, as well as tensile damage in the nearby zone. Explosion-induced impact load plays minor role in neighboring tunnel where the hairline cracks take place at lining without instant instability phenomenon.%以贵州某公司扩建技改工程横三路隧道为依托,建立三维有限元动力模型,根据公安部门设定15 kg TNT炸药的要求,研究爆炸冲击荷载作用下二次衬砌结构变形特性、力学响应及能量分布.研究表明迎爆侧隧道结构出现能量集聚现象,大部分衬砌结构振动速度大于爆破安全规程的允许标准;爆炸所在的隧道衬砌结构局部破坏,但不会大面积坍塌.爆炸区域隧道衬砌以剪切破坏控制为主,附近衬砌结构发生受拉破坏.炸药冲击荷载对相邻隧道影响相对较小,结构发生开裂,不会造成瞬间垮塌失稳现象.
展开▼
