地铁隧道浅埋段下穿砖混结构房屋爆破振动控制研究

Control of Blasting Vibration in Shallow Depth Tunnel Construction Under Brick and Concrete Residential Buildings

以中国大连地铁的浅埋隧道南关岭镇-南关岭站区间为例,给出了人性化的爆破振动速度控制指标。为控制爆破振动,配置大孔径(直径100mm)减振孔并通过预裂爆破形成两道隔振带;采用上下台阶法开挖,掏槽部位尽量下移,增加起爆点与建筑物的距离,降低掏槽引起的爆破振动;提出孔外小段位非电导爆管雷管实现孔内外综合微差方法,在提高爆破振动主频的同时控制了爆破振动速度。实践证明,该区间的爆破振动控制在1.0cm/s,振动主频158.6Hz,持续时长1 150ms,解决了"爆破扰民"问题。

taking the study of a section of shallow tunnel between Nanguanling town and Nanguanling station of the Dalian Metro in China as example,the blasting vibration velocity control targets are given. For blasting vibration control,a large aperture( 100-mm diameter) damping hole is produced and two vibration isolation bands are formed by pre-split blasting.Using the benching tunneling method,the undercutting part is positioned as low as possible to increase the distance between the initial blasting point and the building and to reduce the blasting vibration caused by the undercutting. The inside and outside comprehensive millisecond method is implemented by placing a small-stage non-electric detonator outside the hole,improving the blasting vibration frequency and at the same time controlling the blasting vibration velocity. Our analysis shows that the blasting vibrations during the blasting are controlled,with a vibration velocity of 1. 0cm / s,vibration frequency of 158. 6Hz,and the vibrations last 1 150 ms. These parameters indicate that the blasting does not cause excessive vibration that will cause disturbance to residents.