隧道下穿既有铁路爆破的稳定控制技术研究

RESEARCH ON CONSTRUCTION CONTROL TECHNOLOGY FOR BLAST IN TUNNEL CROSSING EXISTING RAILWAY

以泰安大型抽水蓄能电站输水隧洞为工程背景,结合国内现有研究成果和规范,研究隧洞穿越京沪铁路时爆破施工的稳定控制技术。以现代信息化施工理论为依据,充分运用现场监控量测,对第1阶段的爆破振速进行监测,通过回归分析,对2个重要的爆破参数K,α进行优化,并应用于第2阶段的现场爆破施工;最终现场监测结果表明,优化后的最大装药量等爆破参数设计合理,该爆破设计在现阶段未对京沪铁路产生较大影响;同时,运用数值模拟的方法,得到地表处的垂直振速随时间的变化规律,所得最大振速符合规范要求,验证该次爆破设计是合理的。该研究成果为今后类似浅埋隧道近距离穿越建筑物的爆破掘进工程在理论上和施工方法上提供了参考借鉴。

Based on the transmission water tunnel in the Tai′an pumped-storage power station,the construction technique about blasting stabilization as tunnel crosses the Beijing-Shanghai Railway is studied,combining with the current study results and codes.The research intends to ensure the construction safety of the tunnel on the stocks and keep the minimum damage to the near railway.According to the modern information construction theory,the field monitoring technique is used to obtain the blasting vibration velocity during the first phase.And then the regression analysis is carried out using the monitoring data.Based on the regression analysis,the blasting parameters of the latter phase are optimised and applied during the field construction of the second phase.The final monitoring result indicates that the operation of the railway is not influenced by the construction of tunnels obviously.At the same time,the numerical simulation is employed and the variable rule about the vertical vibration velocity with time is received through the simulation.The largest blasting velocity of the surface near the embankment obtained by the numerical simulation can be proved to be accordance with the criterion,which validates that this kind of control technique about blasting stabilization is reasonable and ensure the safety of the tunnel construction and railway management.The problem about new tunnel crossing neighbouring railway is solved,which offers the theoretical and methodological experiences to the similar engineering.