隧道爆破现场高速图像采集与精确控制爆破参数研究  

High-speed photography image acquisition system in tunnel blasting and parameters study on precisely controlled blasting

作　　者：龚敏[1] 吴昊骏 GONG Min;WU Haojun(School of Civil and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China)

机构地区：[1]北京科技大学土木与资源工程学院,北京100083

出　　处：《爆炸与冲击》2019年第5期1-10,共10页Explosion and Shock Waves

基　　金：国家自然科学基金(51678048);重庆市科技开发计划重点项目(cstc2014yykfB30002)

摘　　要：受隧道内环境恶劣、相机防护等诸多因素制约,隧道现场爆破的高速图像采集与分析尚未实现,而这对精准控制爆破参数非常重要。以重庆某隧道为研究背景,在解决现场测试技术难题基础上,得到隧道爆破过程完整图像并同时获取爆破振动数据;据此分析了隧道爆破岩石破裂现象:炸药起爆15～18 ms后岩体移动,21 ms左右形成空洞并不断扩展后抛出;探讨了同对掏槽眼爆破协同作用时间与微差降振时间之间的矛盾,研究表明兼顾二者作用的起爆时差为8～50 ms;通过分析爆破裂隙扩展曲线特点并结合实测振动数据,确定起爆54 ms时形成第二临空面,较按过去方法确定的时间更精确,以此进行现场掏槽段位设计的降振效果良好;研究结果可为精准控制爆破提供参考。Parameter design of precise controlled blasting in urban tunnels is crucial, which needs the high- speed photography image acquisition and study on the dynamic failure process of rock on field. However, it has not been studied in-depth in the past due to restrict of many factors, the factors include protection of the camera and the bad environment. Based on the technical problems tests on field are solved in a tunnel in Chongqing, China. Original data that include the images of the complete blasting process in tunnel and the blasting vibration data are collected simultaneously, which is the basis for analyzing the phenomenon of rock burst during blasting. 15 18 ms after initiation, the rock masses begin to move and caves are expanded continuously while the rock masses are thrown at about 21 ms. The blast effects is much better if the millisecond delay time between two blast-holes sets 8 50 ms, which can balance the contradiction between two blasting effects, one is the blasting synergetic effect between a pair of cutting holes, and the other is vibration reduction effects of millisecond blasting. The second free face is formed at 54 ms by analyzing the characteristics of crack propagation curves combined with field-measured vibration data. The method is more accurate than the time determined by past methods. Based on this, the optimized on-field delay design of detonators was carried out and got good vibration reduction results. The results can serve as a reference for precise controlled blasting of tunnel in the future.

关 键 词：隧道爆破 数字高速摄像方法 微差爆破 振动控制 岩石破裂过程 

分 类 号：O389[理学—流体力学]