兰渝铁路范家坪隧道出口危岩落石分析及防护设计

摘要

根据兰渝铁路范家坪隧道出口危岩落石发育情况,利用rockfall软件,建立危岩落石运动模型,分析落石的运动特征,实现危岩落石可视化,结合落石运动轨迹、落点分布情况、冲击能量、冲击力、弹跳高度、位移偏移量等研究成果,提出接长明洞和主被动防护相结合的落石综合防护措施.结果表明:在坡面坡积层和明洞回填土缓冲和消耗作用下,接长明洞和主被动防护网相结合的方法可有效防护危岩落石,降低落石冲击风险,保证洞口的安全.可保证隐式中墙复合式连拱隧道施工安全.%Based on the rockfall development of Lanzhou-Chongqing railway Fanjiaping Tunnel exit,the rockfall software to establish the dangerous rock movement model,analyze the motion characteristics of rockfall and realize the visualization of rockfall.In view of the trajectory,distribution,impact energy,impact force,bounce height,displacement offset and other research results associated with rockfall,comprehensive protective measures against rockfall are proposed by means of open cut tunnel extension and combination of active and passive protection.The results show that the proposed measures can effectively protect portal safety and reduce the risk of rockfall and guarantee normal construction of compound arch tunnel.