高速公路隧道下穿既有铁路隧道控制爆破技术

为确保公路隧道爆破施工过程中既有铁路隧道的结构安全,采取了以下措施严格控制爆破振动产生的危害。通过参考相关资料,将上行铁路隧道的振动安全控制标准确定为8.0cm/s。隧道采用台阶法开挖,上台阶爆破循环进尺为0.9m,以控制每次爆破的爆破规模。爆破施工过程中采取了一系列减振技术措施,如增加起爆段别、减少单段起爆药量、增加空孔数量等。爆破取得了良好效果,对既有隧道没有造成影响,达到了预期目的。

Control blasting technology of expressway tunnel underpass existing railway tunnel

For the safety of existing railway tunnel when the new one was in construction,some measurements were taken for controlling damage of blasting vibration.According to relevant safety standard information,the blasting vibration safety control standard was determined to be 8.0cm/s for the existing tunnel.Bench method was used and blasting advance per round of 0.9m was set up to reduce blasting scale at upper bench.A series of techniques were taken during tunnel blasting to reduce the vibration,such as increasing initiation segments,decreasing the charge amount per delay interval,drilling more empty holes and so on.A good blasting effect without any negative impact on the existing railway tunnel was finally achieved.