控爆技术在邻近营业线铁路隧道小净距施工中的应用

Application of Controlled Blasting Technology in Small Net Distance Construction of Adjacent Operating Railway Tunnels

新郁山隧道平导与既有渝怀线铁路隧道水平最小净距只有7m,地质条件差,设计采用控制爆破施工,要求既有隧道爆破振速不大于2.5cm/s,施工难度和风险极大。为确保在隧道平导爆破施工时既有线运营安全可控,通过对爆破振速监测,研究孔眼设计、装药方式及起爆网路设计施工方法,并在正式施工中得到成功应用,保证了隧道平导开挖工程的安全高效完成,并对邻近营业线隧道爆破施工具有很强的指导意义。

The minimum horizontal net distance of the Xinyu Mountain tunnel adit and the existing Chongqing -Huaihua Railway tunnel is only 7m and the geological condition is poor. The design adopts controlled blasting . It is required that the existing tunnel blasting vibration velocity is not more than 2.5 cm/s , so the construction is extremely difficult and risky . In order to ensure the safe and controllable operation of the existing railway during the tunneling and blasting construction , through the monitoring of the blasting vibration velocity , the study of the hole design , the charging method and the design method of the detonation network , and the successful application in the formal construction , the safe and efficient completion of tunneling excavation gas been ensured and it has a strong guiding significance for the tunneling blasting construction of the adjacent business line .