装药结构对硬质岩隧洞轮廓成型效果的影响研究  

Study on Influence of Charge Structure on Contour Forming Effect of Hard Rock Tunnel

作　　者：张光辉 张家托 王洋 程远龙 蒋宏杰 陈明[2] ZHANG Guang-hui;ZHANG Jia-tuo;WANG Yang;CHENG Yuan-long;JANG Hong-jie;CHEN Ming(Luotian Pingyuan Pumped Storage Co.,Ltd.of Hubei Energy Group,Huanggang 438000,China;School of Water Resources and Hydropower,Wuhan University,Wuhan 430072,China)

机构地区：[1]湖北能源集团罗田平坦原抽水蓄能有限公司,黄冈438000 [2]武汉大学水利水电学院,武汉430072

出　　处：《爆破》2024年第2期15-22,169,共9页Blasting

基　　金：国家自然科学基金(No.51979205);湖北省博士后创新研究岗位资助项目(博后编号:279265)。

摘　　要：硬质岩隧洞的轮廓成型效果对提高围岩稳定性和降低支护成本具有重要意义。以优化隧洞轮廓孔单孔装药量和装药结构为目标,首先,理论分析了隧洞爆破中轮廓孔装药参数的取值范围;其次,分别以1200 g、900 g、750 g、600 g的单孔装药量进行了硬质岩隧洞爆破试验,并借助激光扫描仪对隧洞轮廓成型效果进行了扫描分析;最后,利用断裂力学模型分析了不同单孔装药量的隧洞轮廓成型效果。结果表明:当硬质岩隧洞的轮廓孔装药参数在合理范围内时,单孔装药量越小,爆破产生的孔间裂缝数量越少,岩体损伤范围也越小;当装药量由1200 g降低至600 g时,隧洞轮廓超挖体积由6.53 m^(3)降低至2.02 m^(3),但由孔位误差导致的轮廓欠挖体积由0.15 m^(3)增大0.26 m^(3);断裂力学模型在硬质岩隧洞轮廓爆破的模拟中优于损伤模型,模型计算得隧洞轮廓上的半孔数与观察值吻合较好。研究成果可为类似硬质岩隧洞爆破开挖中轮廓成型效果优化提供技术与方法借鉴。The contour forming effect of a hard rock tunnel is of significant importance in enhancing the stability of surrounding rock and reducing support costs.This paper aims to optimize the single-hole charge and charge structure for tunnel contour holes.The theoretical range of charge parameters for blasting contour holes in tunnels is proposed initially.Subsequently,blasting tests were conducted on a hard rock tunnel using single-hole charges of 1200 g,900 g,750 g,and 600 g respectively,with all tunnel contours analyzed by a laser scanner.Finally,a fracture mechanics model was employed to simulate the contour blasting of the hard rock tunnel with different single-hole charges.The results indicate that when charging parameters are within a reasonable range,smaller single-hole charges result in fewer cracks between blasting holes and less damage to the surrounding rock.Although decreasing the charging amount from 1200 g to 600 g reduces over-excavation volume from 6.53 m^(3)to 2.02 m^(3),it also increases under-excavation volume caused by hole position error from 0.15 m^(3)to 0.26 m^(3)along the tunnel contour.Furthermore,compared to the damage mechanics model,the fracture mechanics model proves superior in simulating contour blasting for hard rock tunnels as evidenced by good agreement between calculated results and experimental data regarding half hole numbers on the tunnel's contour.

关 键 词：隧洞爆破 轮廓爆破 单孔装药量 空气间隔装药 断裂力学模型 

分 类 号：U25[交通运输工程—道路与铁道工程]