隧道爆破振动控制技术研究

Research on the Control Technology for Tunnel Blasting Vibration

研究目的:复杂环境下浅埋隧道钻爆施工的爆破振动问题最为敏感,工程实践中需要既能实现快速掘进又能降低敏感区段爆破振动的爆破技术。研究结论:结合开元寺隧道和杭州引水隧洞钻爆掘进中的爆破振动测试和分析,发现这两个埋深25 m左右的隧道掘进中,掏槽爆破产生的地表振动最为强烈。试验证明采用多级复式楔形掏槽可以有效降低爆破振动,同时利用高精度延时雷管或数码电子雷管调整掏槽爆破起爆时差,可以实现振动波错峰减振,并能改善掏槽效果,提高炮孔利用率。爆破试验过程中配合爆破振动监测,不断调整和优化掏槽爆破方案,最终顺利通过隧道浅埋振动敏感区,而且平均单炮进尺在3 m左右,地表爆破振动控制在1.5～2.5 cm/s。达到保证安全的前提下实现快速钻爆施工。

Research purposes： The blasting vibration is very sensitive in construction of the shallow burying tunnel under complicated environment with bore blasting method. The blasting technology that can realize rapid boring and reduce the blasting vibration in the sensitive area is really needed in the tunnel construction. Research conclusions： From the tests and analyses of the blasting vibration in construction of 25 m buried deep Kaiyuansi Tunnel and the diversion tunnel in Hangzhou with bore blasting method, it is found the ground vibration caused by undermine blasting is the most serious. The experiment shows application of multi - stage wedge undermine can reduce the blasting vibration effectively, and application of high - precise delay blasting cap or digital electric blasting cap to adjust the time difference of the undermine blasting can reduce the vibration of vibration wave by alternating peak, improve the undermine effect and utilization rate of the hole. Based on the monitoring the blasting vibration during the blasting experiment, the undermine blasting plan is continuously improved and optimized to achieve the goal of passing through the shallow buried sensitive area of the tunnel with about 3 m boring of each blasting and the ground blasting vibration of 1.5 - 2.5 cm/s. In this case, the rapid construction with bore blasting method is realized.