地铁浅埋隧道爆破振动效应试验与数值模拟研究

以新疆乌鲁木齐市地铁1号线东线隧道中营工-小西沟区间段为工程背景，对地铁浅埋隧道爆破振动进行了多次监测试验，发现地铁浅埋隧道地表掌子面前后16 m监测范围内存在空洞效应现象，随着与掌子面距离由小变大，空洞效应现象出现先增强后减弱的趋势直至最后消失；运用LS-DYNA程序，采用拉格朗日算法和完全重启动相结合的方法对地铁浅埋隧道爆破振动进行数值模拟，也得出了地铁浅埋隧道地表掌子面前后存在空洞效应现象的结论，空洞效应现象存在的区域为掌子面两侧10 m范围内，空洞效应现象在掌子面两侧6 m处最为显著.通过将掏槽孔装药一次爆破调整为多分段爆破，减小了掏槽孔单段起爆药量，降低了掏槽孔爆破产生的地表振动效应. 

Experimental and Numerical Simulation Study on Blasting Seismic Effect of Subway Shallow Buried Tunnel

This paper took the Zhongyinggong-Xiaoxigou segment of Xinjiang Urumqi Line 1 subway tunnel as the engineering background. By conducting several vibration monitoring tests on the subway tunnel surface it was found that hollow effect phenomenon existed in the monitoring range of 16 m before and behind the tunnel face of the shallow subway tunnel. As the measure points got further from the tunnel face, hollow effect phenomenon showed the tendency of going up first, declining later, and disappeared finally. In this paper, lagrange algorithm and complete restart were adopted to simulate the blasting of subway shallow tunnel using LS-DYNA program. It showed that hollow effect phenomenon existed in the range of 10 m before and behind the tunnel face of the shallow subway tunnel; this phenomenon was most significant at the point of 6 m before and behind the tunnel face. By changing the blasting of the cut hole charge into multi section blasting, the single-stage detonation dose and the surface vibration effect were reduced. It not only ensured the safety of subway construction but also effectively controlled the impact of tunnel blasting construction on surrounding buildings.