大断面隧道空孔直线掏槽爆破高效掘进方法  

Efficient Driving Method for Large Section Tunnel by Burn Cut Blasting with Uncharged Holes

作　　者：王玮 怀平生 降世良 WANG Wei;HUAI Ping-sheng;JIANG Shi-liang(Lianyungang Mingda Engineering Blasting Co.,Ltd.,Lianyungang 222021,China;International Engineering Co.,Ltd.of China Railway 12 Bureau Group Ltd.,Beijing 100176,China)

机构地区：[1]连云港明达工程爆破有限公司,连云港222021 [2]中铁十二局集团国际工程有限公司,北京100176

出　　处：《爆破》2022年第3期76-81,共6页Blasting

摘　　要：在阿联酋阿提哈德铁路大断面隧道项目中,为满足当地高标准建设要求和确保按期完工,采用了空孔直线掏槽爆破方法,并组建工程数学模型输出爆破参数指导施工。综合考虑现场钻头直径后,利用数学模型的计算结果设计了4个102 mm空孔和6个64 mm空孔两种空孔直线掏槽方案,理论开挖进尺分别为4.5 m和4 m,作为对比设计了理论开挖进尺为4 m的楔形掏槽方案。经T_(7)隧道现场测试统计,4空孔方案平均每循环进尺为4.3 m,炮孔利用率为95.6%,较对比实施的楔形掏槽方案提高0.6 m每循环。经T_(10)隧道现场测试统计,6空孔方案平均每循环进尺为3.8 m,炮孔利用率为95.0%,较对比实施的楔形掏槽方案最大单段药量降低85%,跟踪监测数据显示,最大爆破振动速度始终低于控制指标,保障了T_(10)隧道周边燃气管线的安全。空孔直线掏槽在项目中的大量应用验证了工程数学模型的有效性,同时也表明该方法在中硬及坚硬条件下的大断面隧道中,与传统的楔形掏槽爆破方法相比可加快施工进度,降低爆破成本,并能有效地控制爆破振动,具有显著的经济价值。Burn cut blasting with uncharged holes was adopted in a large-section tunnel project of Etihad Railway in the United Arab Emirates to ensure timely completion of the construction with a high standard.Engineering mathematical models are established to determine blasting parameters and guide the construction process.Considering the bit diameter on site,two burn cut plans with four 102 mm-diameter uncharged holes and six 64 mm-diameter uncharged holes are presented by using mathematical models.The theoretical excavation footage for each of the two plans is 4.5 m and 4 m,respectively.As a contrast,a wedge cut scheme is designed with a theoretical footage of 4m.According to the field test statistics of T_(7) tunnel,the average footage per cycle of the 4-uncharged-hole plan is 4.3 m with a hole efficiency of 95.6%,which is 0.6 m more than the footage of wedge cut plan.According to the field test statistics of T_(10) tunnel,the average footage per cycle of the 6-uncharged-hole plan is 3.8 m with a hole efficiency of 95.0%.Compared to the wedge cut plan,the maximum charge per delay has decreased by 85%,which has controlled the PPV below the allowed value indicated by the monitoring data.Numerous applications of burn cut with uncharged holes in this project have validated the effectiveness of the engineering mathematical model in medium-hard and hard rocks.At the same time,the burn cut plan can speed the construction process,reduce blast costs,and effectively control blast vibrations.

关 键 词：大断面隧道 空孔直线掏槽 隧道爆破 爆破进尺 爆破振动 

分 类 号：TD236[矿业工程—矿井建设]