C型开口聚能管爆破机理与隧道光爆优化效果研究  

Study on blasting mechanism of C-type opening energy-gathering tube and optimization effects on tunnel smooth blasting

作　　者：朱凯 张学民[1,2] 龙立敦[3] 武朝光 周贤舜 万正 伍福寿 ZHU Kai;ZHANG Xuemin;LONG Lidun;WU Chaoguang;ZHOU Xianshun;WAN Zheng;WU Fushou(School of Civil Engineering,Central South University,Changsha 410075,China;Key Laboratory of Heavy-haul Railway Engineering Structure,Ministry of Education,Central South University,Changsha 410075,China;Guizhou Highway Engineering Group Co.Ltd.,Guiyang 550000,China)

机构地区：[1]中南大学土木工程学院,湖南长沙410075 [2]中南大学重载铁路工程结构教育部重点实验室,湖南长沙410075 [3]贵州省公路工程集团有限公司,贵州贵阳550000

出　　处：《中南大学学报（自然科学版）》2024年第10期3849-3863,共15页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(51978671);贵州省交通运输厅科技项目(2023122003)。

摘　　要：超欠挖是钻爆法隧道施工的常见问题,与光面爆破效果密切相关。为有效解决隧道掘进超欠挖及常规聚能管不利于光爆层岩体破碎的问题,以优化调节爆轰能量为思路,采用理论分析和数值模拟方法研究C型开口聚能管的裂岩机理。研究结果表明采用C型开口聚能管与采用常规聚能管和常规药包的光面爆破相比具有以下显著优势:1)聚能管开口能显著提高光爆层岩体应力,使光爆层岩体率先损伤,引导岩体充分破碎;2)开口的存在间接增大了聚能方向上的拉应力,裂纹沿聚能方向定向扩展,超欠挖控制效果良好;3)与常规聚能管相比,非聚能方向的岩体应力降低更多,裂纹拓展更少,这更易于保护开挖轮廓线外侧围岩;4)C型开口聚能管可提高周边孔孔距和光爆层厚度,有利于提高光面爆破的效果;C型开口聚能管与常规爆破相比,超挖量降低83%,欠挖量降低68%,半孔率更高且开挖轮廓更平整,并可在一定程度上降低钻孔量和炸药单耗。总体上,C型开口聚能管的应用有利于提高隧道钻爆法施工的效率和质量。Over and under excavation is a common issue in tunnel construction using the drilling and blasting method,and it is closely related to the effects of smooth blasting.To solve the issues of over and under excavation,and inadequate fragmentation in the smooth blasting layer using conventional energy-gathering tube,the distribution of explosive energy was taken as an optimization object,and theoretical and numerical methods were employed to study the rock breaking mechanism of the C-type opening energy-gathering tube.The results show that compared with the conventional energy-gathering tube and conventional charge,the C-type opening energy-gathering tube has significant advantages as follows.1)The opening of the energy-gathering tube significantly increases the stress in the rock mass of the smooth blasting layer,causing the rock mass of the smooth blasting layer to be damaged first,thereby guiding the rock to be fully fragmented.2)The presence of the opening indirectly increases the tensile stress in the energy-gathering direction,causing cracks to expand directionally along this direction,effectively controlling over and under excavation.3)Compared with conventional energy-gathering tube,the stress in the rock mass in the non-energy-gathering direction is furtherly reduced,and there is less crack expansion,making it easier to protect the surrounding rock outside the excavation contour line.4)The C-type opening energy-gathering tube can increase the distance between surrounding holes and the thickness of the smooth blasting layer,which is beneficial in improving the effects of smooth blasting.Moreover,the C-type opening energy-gathering tube reduces over-excavation by 83%and under-excavation by 68%compared with conventional blasting.It also offers advantages in increasing the half-hole rate and the smoothness of the excavation profile,and to a certain extent,reduces the amount of drilling and the consumption of explosives per unit.On the whole,the application of the C-type opening energy-gathering tube is beneficia

关 键 词：钻爆法隧道 超欠挖优化 聚能爆破 C型开口聚能管 光面爆破 

分 类 号：U45[建筑科学—桥梁与隧道工程]