新建京张高铁立体交叉隧道爆破振动控制研究

Study on Blasting Vibration Control of Three-dimensional Cross Tunnel on Beijing to Zhangjiakou High-speed Railway

为研究重载铁路交叉隧道爆破振动规律及控制爆破优化措施,以新建京张高铁草帽山隧道下穿既有唐呼重载铁路北草帽山隧道交叉工程为背景,选取与交叉段岩性相近,围岩等级分别为Ⅲ、Ⅳ及Ⅴ级的洞身段爆破施工,进行爆破振速的现场实测;通过数据拟合,得到相关爆破工程参数K、α;而后通过公式反演得到不同隧道围岩级别下穿时的最大装药量及最小控爆距离;基于经验公式理论分析,提出可实践的优化三段式爆破施工方案。现场试验证实,优化后的三段式爆破方案可以有效地减小爆破施工引起的振动,有助于本隧道下穿工程安全顺利通过。

In order to study the law of blasting vibration and optimization of the tunnel over passing the heavy haul railway,this paper selects the tunnel section with similar mechanical properties at the cross section for blasting vibration monitoring test,and classifies the collected data according to the rock grade with reference to the three-dimensional cross tunnel on Beijing to Zhangjiakou high-speed railway on Caomaoshan mountain. Through data fitting, relevant blasting engineering parameters K and α are obtained; then with formula inversion, corresponding charge and blasting distance under different surrounding rock grades is determined. Based on the theoretical analysis of empirical formula,feasible three-stage blasting construction scheme is put forward. The Field test confirms that the optimized blasting program can effectively reduce the vibration caused by blasting construction to allow successful construction of the tunnel.