大断面隧道“楔形掏槽+高能孔”布设方法研究  

Research on Layout Method of“Wedge Cut+High Energy Holes”for Large Section Tunnels

作　　者：漆涛 陶铁军 田兴朝 谢财进 万安桐 张厚英 QI Tao;TAO Tie-jun;TIAN Xing-chao;XIE Cai-jin;WAN An-tong;ZHANG Hou-ying(School of Civil Engineering,Guizhou University,Guiyang 550025,China;School of Mining,Guizhou University,Guiyang 550025,China;Guizhou Datong Road and Bridge Engineering Construction Co.,Ltd.,Guiyang 550008,China)

机构地区：[1]贵州大学土木工程学院,贵阳550025 [2]贵州大学矿业学院,贵阳550025 [3]贵州大通路桥工程建设有限公司,贵阳550008

出　　处：《爆破》2024年第3期95-103,120,共10页Blasting

基　　金：国家自然科学基金地区科学基金项目(52064008);贵州省科技计划项目(黔科合支撑[2023]一般358)。

摘　　要：在大断面隧道爆破中,由于掏槽孔的位置布置不合理,导致掌子面中间岩体时常出现“鼓肚”现象。为解决大断面隧道爆破“鼓肚”现象,提出了一种“楔形掏槽+高能孔”的炮孔布设新方法。以云南省鲁巧高速共和村隧道为工程背景,采用有限元软件LS-DYNA建立“楔形掏槽+高能孔”的数值模型,研究了炮孔底部有效应力和岩体动态损伤,并与现场隧道掏槽爆破方案进行对比,同时结合现场爆破试验对所提新方法进行验证。研究结果表明:现场实验验证了“楔形掏槽+高能孔”炮孔布设方法可有效消除“鼓肚”现象,减少掏槽孔和数码电子雷管数量,确定了该方法的合理性以及适用性;主掏槽孔底部测点1、2和3产生的应力值较小,当高能孔爆炸后,应力急剧上升至454.9 MPa,可对主掏槽孔爆破后遗留的中间保留岩体进行有效破除;采用改进后的爆破方法,掘进效率提升16.9%,炮孔平均利用率达到91.5%,炸药单耗降低19.7%。提出的大断面隧道“楔形掏槽+高能孔”布设方法在保障施工安全的同时,达到了降低成本提高施工效率的效果,为大断面隧道爆破方案优化设计提供借鉴。For large cross-section tunnel blasting,the rock mass in the middle of the tunnel face often experiences the phenomenon of“bulging”due to the unreasonable arrangement of the cutting holes.In order to eliminate the“bulge belly”phenomenon in large cross-section tunnel blasting,a new method of“wedge cut+high-energy hole”blast hole layout was proposed.Taking the Gonghe Village Tunnel of the Luqiao Expressway in Yunnan Province as the engineering background,a numerical model of“wedge-shaped cut+high-energy hole”was established using finite element software LS-DYNA.The effective stress at the bottom of the blast hole and dynamic damage of the rock mass were studied and compared with the on-site tunnel cut blasting plan.At the same time,the proposed new method was verified through on-site blasting experiments.The research results indicate that the“wedge cut+high-energy hole”blasting hole layout method can effectively eliminate the“bulge”phenomenon,reduce the number of cut holes and digital electronic detonators,and determine the rationality and applicability of this method.Besides,the stress values generated by measuring points 1,2,and 3 at the bottom of the main cutting hole are relatively small.As the stress sharply rises to 454.9 MPa,the middle-retained rock mass can be effectively broken after the main cutting hole blasted with the high-energy hole explodes.Using the improved blasting method,the excavation efficiency increased by 16.9%,the average utilization rate of blast holes reached 91.5%,and the explosive consumption reduced by 19.7%.The proposed layout method of“wedge-shaped cutting+high-energy holes”for large cross-section tunnels can not only ensure construction safety,but also achieve the effect of reducing costs and improving construction efficiency.

关 键 词：大断面隧道爆破 楔形掏槽 高能孔 “鼓肚”现象 

分 类 号：TD235.3[矿业工程—矿井建设]