隧道下穿既有省道不稳定坡体微扰动施工技术研究

Study on Micro Disturbance Construction Technology of Tunnel Under Crossing Existing Provincial Highway Unstable Slope

为解决山岭重丘区公路隧道下穿既有省道施工扰动问题,采用抗滑桩与锚索防护+拱盖法进洞+机械开挖与控制爆破+洞内支护加强措施的微扰动施工技术,并结合现场爆破振动监测数据,对施工参数进行控制,分析微扰动施工技术的合理性。工程实践表明,微扰动施工技术可减小对围岩的扰动,有利于隧道洞顶坡体稳定,保证隧道顺利贯通,且不对既有省道交通造成影响,具有良好施工效果。

In order to solve the construction disturbance problem of highway tunnel under crossing existing provincial highway in mountainous hilly areas,the micro disturbance construction technology of anti slide pile and anchor cable protection,arch cover method,mechanical excavation and controlled blasting,strengthening measures of support in the tunnel is adopted.Combined with the on-site blasting vibration monitoring data,the construction parameters are controlled,and the rationality of micro disturbance construction technology is analyzed.The engineering practice shows that the micro disturbance construction technology can reduce the disturbance to the surrounding rock,which is conducive to the stability of the tunnel top slope,ensures the smooth connection of the tunnel,and does not affect the traffic of the existing provincial highway,so it has good construction effect.