同时起爆的双孔台阶模型试验研究  

Experimental study on simultaneous initiation in double-hole bench model

作　　者：刘鑫[1] 杨军[1] 唐红亮 LIU Xin;YANG Jun;TANG Hongliang(State Key Laboratory of Explosion Science and Technology,Beijing Institute of Technology,Beijing 100081,China)

机构地区：[1]北京理工大学爆炸与科学国家重点实验室,北京100081

出　　处：《岩石力学与工程学报》2020年第12期2460-2470,共11页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(51774043)。

摘　　要：随着数码电子雷管及逐孔起爆技术在露天矿山开采的广泛应用,毗邻双孔的应力波相互叠加作用已成为爆破技术领域研究的热点。利用花岗岩按照实际露天台阶缩比1/50制作双孔台阶模型,建立高速三维数字图像相关试验系统,基于全场应变、高速摄影图像和应力波分布特征对同时起爆的双孔台阶模型试验进行研究。试验结果初步表明:水平方向的主应变集中区优先产生于竖直方向的主应变集中区,结合高速摄影图像得到模型表面裂纹的演化过程,进一步地提出水平裂纹的起裂时间和起裂位置的判断方法;为了明确台阶表面的面外运动对变形测量的影响,对比3D-DIC与2D-DIC的分析结果,发现单一测点的最大应变误差大概为3.6%;装药量影响水平裂纹的起裂时间、水平裂纹张开角和裂纹总数量;最后,对双孔台阶模型同时起爆的应力波分布状态进行了分析。With the extensive application of digital electronic detonator and hole-by-hole initiation technology in open pit mining,the stress wave interaction of adjacent double holes has become a research hotspot in the field of blasting technology.In this paper,a double-hole bench model with a proportion of 1/50 to typical full-scale bench is designed from granite,an experimental system of high-speed three-dimensional digital image correlation is established,and simultaneous initiation in double-hole bench model is studied based on full-field strain,high-speed photographic image and stress wave distribution characteristics.The preliminary experimental results show that the horizontal principal strain concentration area occurs prior to the vertical principal strain concentration area.The surface crack evolution process of the bench model is obtained based on the high-speed photographic images,and then a method to determine the initiation time and location of the horizontal crack is proposed.In order to investigate the influence of the out-of-plane movement of the bench surface on the deformation measurement,the analysis results of 3 D-DIC and 2 D-DIC are compared,and it is found that the maximum strain error at a single measuring point is about 3.6%.The charge affects the horizontal crack initiation time,the horizontal crack opening angle and the total number of cracks.Finally,the stress wave distribution of simultaneous initiation of double-hole bench model is analyzed.

关 键 词：岩石力学 台阶爆破 数字图像相关方法 高速摄影 全场应变 裂纹 应力波 

分 类 号：TU45[建筑科学—岩土工程]