隧道光面炮孔的围岩夹制力分布研究

Study on Distribution of Surrounding Rock Clamping Force of Smooth Blasting Hole in Tunnel

为了优化光面爆破装药结构设计,采用LS-DYNA数值模拟软件对光爆孔周边的岩石夹制力进行模拟,分析了不同围压、不同掘进断面及不同炮孔长度对炮孔周边岩石夹制力的影响。研究结果表明:隧道掘进断面的大小对夹制力的影响较小,而围压对夹制力的影响较大,其随围压呈线性增大。不同孔深情况下,夹制力沿炮孔深度的分布趋势相同。在孔口段应力集中较小,此段的夹制力最小;在炮孔中部呈现平缓的增长趋势,在接近孔底处呈陡然上升的趋势,此段为夹制力最大段。以上研究结果为空气间隔装药结构的设计提供参考,有助于设计的精细化。

In order to optimize the charge structure design of smooth blasting,LS-DYNA numerical simulation software was used to simulate the rock clamping force around the smooth blasting hole,and the effects of different confining pressures,different excavation sections and different blast hole lengths on the rock clamping force around the blast hole were analyzed.The results show that the size of the tunnel excava⁃tion section has little effect on the clamping force,while the confining pressure has a great influence on the clamping force,which increases linearly with the confining pressure.Under different hole depths,the distri⁃bution trend of clamping force along the hole depth is the same.The stress concentration in the orifice section is small,and the clamping force in this section is the smallest.The clamping force shows a gentle growth trend in the middle of the hole,and shows a steep upward trend near the bottom of the hole.This section is the maximum clamping force section.The above research results provide a reference for the design of airspaced charge structure and contribute to the refinement of design.