小净距隧道施工中减振技术研究

双洞小净距隧道中夹岩柱一般都比较小,因此后行洞爆破施工对先行洞有较明显的影响。本文介绍云(阳)-万(州)高速公路张家山隧道小净距段施工中,采用小循环进尺、分区开挖的台阶分部法和短台阶断面法开挖,并控制最大段装药量、段间隔时间、确定合理的爆破参数和对先行洞最不利部位振速监测等一系列爆破减振控制技术,保证了小净距段先行洞的安全和后行洞施工的顺利进行。

Studies on Week Blasting Vibration Technological Measures Performed in Small Clear Distance Tunnel

In general, as the small clear distance between two-line tunnels, excavating blast in following tunnel will affect structure safety of the existing ones. Based on the practical situation of small clear distance zone at the ZHANGJIASHAN Tunnel in the YUN-WAN Expressway, the construction control technology were discussed concerning weak-vibration blast, which contained a series of technological measures such as mini-bench constructing method, excavating sequence and monitoring adopted in existing tunnel for control the blasting vibration. Results showed that the structure safety of existing tunnel and the construction of following one were assured.