摘要
采用动态光弹性技术,探讨了在保护性石料开采中使用的控制切割爆破技术中导向空孔的存在对切割缝的控制作用,分析了工程中常见的几种空孔配置形式的导向机理。考察了爆破应力波入射空孔时空孔周边的动应力分布情况。结果发现,正是由于应力波在空孔周边附近及炮孔爆炸时高压气体的准静态共同作用形成的动拉应力集中使沿炮孔与空孔连心线方向的裂纹优先扩展形成切割主裂缝,从而达到控制切制的目的。
By using dynamic photoelastic technology, the control effect of the leading hole to the cutting crack extension was investigated in cutting blasting used in some protective stone materials mining. The orientation control mechanism of several arrangments of uncharged boreholes with boreholes often used in ehgineering was analysed. The dynamic stress distribution near the leading hole was studied when stress wave is incident upon the leading holes. It was found that the dynamic tensil stress concentrations near the eadge of the leading holes formed both by the incidence of the stress wave and the quasi-static stress field produced by high pressure gas in boreholes make the cracks, along the direction of two holes, produce and extend easily and previously, so that the main cutting cracks can be formed to control cutting results well.
基金
云南省应用基础研究基金
关键词
控制切割爆破
空孔导向
爆破技术
cutting control blasting
leading holes
dynamic photoelasticity
