超大断面扁平结构隧道矿山法超欠挖优化控制研究  

Optimization on the over/under-excavation of flat and super-large cross-section tunnel with drill and blast method

作　　者：田瑞端 莫冠旺 李响 TIAN Ruiduan;MO Guanwang;LI Xiang(Shanghai Tunnel Engineering Co.,Ltd.,Shanghai 200032,China;School of Civil Engineering,SunYat-Sen University,Zhuhai 519082,Guangdong,China)

机构地区：[1]上海隧道工程有限公司,上海200032 [2]中山大学土木工程学院,广东珠海519082

出　　处：《隧道与地下工程灾害防治》2024年第2期84-98,共15页Hazard Control in Tunnelling and Underground Engineering

基　　金：国家自然科学基金面上资助项目(52274106);上海隧道工程有限公司专项研究科研资助项目(2022-sk-19)

摘　　要：为了对超大断面扁平结构隧道矿山法开挖过程中存在的超欠挖现象进行优化控制,以某公路隧道为例,分别对隧道Ⅲ、Ⅳ级围岩段建立数值模型,再现隧道断面爆破过程,利用现场实测数据对数值模型进行验证,并根据计算结果分析不同爆破方案中爆破损伤云图、爆破轮廓线、最大超欠挖距离、平均超欠挖距离、超挖面积的变化规律,讨论不同周边孔孔距、掏槽孔孔距以及各炮孔装药量对隧道爆破开挖超欠挖的影响,并在此基础上对爆破方案进行优化。数值模拟结果结合现场实测数据,最终得出有效减小爆破超挖现象的最优施工方案为:Ⅲ级围岩调整周边孔孔距为1 m,Ⅳ级围岩调整周边孔孔距为0.8 m。To optimize and control the over/under-excavation phenomena observed in the excavation of flat and superlarge cross-section tunnels using the drill and blast method.A highway tunnel served as a case study,where numerical models for tunnel sections with gradeⅢandⅣsurrounding rock were established.The blasting process of the tunnel cross-section was replicated,and field-measured data were utilized to validate the numerical models.Analyses were performed on the variations in blast damage nephograms,blast profiles,maximum and average over/under-excavation distances,and over-excavation areas across different blasting schemes.These analyses quantified the impact of varying peripheral and cut hole spacings,as well as the charge quantities in blast holes,on the over/under-excavation during tunnel blasting.Subsequent to these analyses,the blasting schemes were optimized.By integrating numerical simulation outcomes with field-measured data,an optimal construction scheme was deduced that effectively minimizes overexcavation:the peripheral hole spacing was adjusted to 1 m for gradeⅢsurrounding rock and to 0.8 m for gradeⅣ.

关 键 词：超大断面 扁平结构 光面爆破 超欠挖控制 数值模拟 

分 类 号：U455.4[建筑科学—桥梁与隧道工程]