城市超浅埋小净距隧道爆破振动响应特性研究

为分析浅埋小净距隧道爆破引起地表及临近先行隧道振动的影响，开展爆破振动现场监测实验，得到了各典型爆破段引起地表及已开挖隧道迎爆侧的振动传播规律。结果表明：地表及邻近隧道对应爆破掌子面前后25m范围内，前方质点速度大于后方，但后方各点的振速衰减比前方快；地表各测点振动速度垂直方向分量最大，切线方向与径向方向相近，已开挖隧道迎爆侧边墙各测点径向方向分量最大，为垂向和轴向的1.5～4.0倍；掏槽和扩槽爆破时受岩石夹制作用大，引起地表和已开挖隧道振动速度相对较大，辅助和周边装药段爆破振动较小；并依据国家《爆破安全规程》，对隧道易破坏位置进行了分析。研究成果可为同类隧道爆破开挖与振动控制提供参考。

Blasting vibration response characteristics of urban super-shallow#br#buried small clear distance tunnel

In order to analyze the impact of shallow-buried and small clear distance tunnel blasting on the ground surface and the vibration of the adjacent excavated tunnel, an on-site blasting vibration monitoring experiment was carried out. And the vibration characteristics and changes of the ground surface and the side wall of the preceding excavated tunnel induced by the typical segment blasting were obtained. The results showed that: on the ground surface and the excavated tunnel, the vibration velocity measured at a symmetrical position within 25m in front and back of the blasting surface, the particle velocity in front is greater than the rear, but the vibration velocity of each point at the rear decays faster than the front. The vertical velocity component of the vibration velocity at each measuring point on the ground surface is the largest, and the tangential direction is similar to the radial direction. The vertical component is the largest, which is 1.5-4.0 times of the tangential and radial directions-the cut and expansion blasting is greatly affected by the rock clamp, which causes relatively high vibration velocity of the ground surface and the excavated tunnel, and the auxiliary and surrounding charge section blasting is small. According to the national “Blasting Safety Regulations”, the vulnerable positions of the tunnel are also analyzed. This research work can provide a reference for blasting excavation and vibration control in similar tunnels.