双线隧道爆破初期支护结构的动态响应特性  

Dynamic response characteristics of the initial support structure of the double-track tunnel blasting

作　　者：黄传胜 阳鑫 林继华 徐昊 胡德玉 任开富 HUANG Chuansheng;YANG Xin;LIN Jihua;XU Hao;HU Deyu;REN Kaifu(School of Civil and Architectural Engineering,East China University of Technology,Nanchang 330013,Jiangxi Province,P.R.China;Jiangxi Geological Engineering Group Co.Ltd.,Nanchang 330029,Jiangxi Province,P.R.China;Guizhou Road and Bridge Group Co.Ltd.,Guiyang 550001,Guizhou Province,P.R.China)

机构地区：[1]东华理工大学土木与建筑工程学院,江西南昌330013 [2]江西省地质工程集团有限公司,江西南昌330029 [3]贵州路桥集团有限公司,贵州贵阳550001

出　　处：《深圳大学学报（理工版）》2024年第4期490-498,共9页Journal of Shenzhen University(Science and Engineering)

基　　金：国家自然科学基金资助项目(42061011,41977236);东华理工大学博士科研启动基金资助项目(DHBK2019240);江西省研究生创新专项资金资助项目(YC2023-S587)。

摘　　要：在后行洞隧道爆破开挖过程中,保证先行洞隧道的爆破振动安全极为关键.以中国贵州子母岩隧道爆破开挖为工程背景,基于现场监测和数值模拟,分析后行洞爆破开挖时左右线振速峰值衰减规律和应力分布特征,提出了爆破振速安全阈值.研究结果表明,在后行洞进行爆破时,后行洞初期支护振速最大值出现在拱顶及拱腰处,并且拱顶衰减更快;先行洞初期支护结构振速最大值出现在迎爆面侧拱腰处,迎爆面振速峰值由左拱腰、左拱脚和拱顶依次递减,迎爆面初期支护结构振速最大值约为背爆面的4倍;先行洞振速衰减规律与后行洞相同,均为拱顶衰减最快,其次为拱腰;先行洞初期支护结构振速峰值与应力分布基于开挖面呈对称分布,建立基于振速峰值与拉应力的安全准则,先行洞既有衬砌结构的安全振速阈值为10.81 cm/s,确定单段最大装药质量为58.2 kg.研究成果可为双线隧道同时掘进时的隧道安全施工提供参考.In the process of blasting excavation of the later excavated tunnel,it is crucial to ensure the safety of blasting vibration in the first excavated tunnel.Using the blasting excavation of the Zimuyan Tunnel in Guizhou,China,as the engineering background,we analyze the attenuation law of vibration velocity peak of the left and right lines and the stress distribution characteristics based on the field monitoring and numerical simulation methods.The safety threshold of the blasting vibration velocity is also proposed.The results show that during the blasting of the later-excavated tunnel,the maximum vibration velocity of the initial support of the later excavated tunnel occurs at the vault and the arch waist,with faster attenuation at the vault.In the first-excavated tunnel,the maximum vibration velocity of the initial support structure occurs at the side arch waist of the blasting surface,and the vibration velocity peak sequence on the blasting surface is left arch waist > left arch foot > vault, with the maximum vibration velocity at the blasting surface being approximately four times that of the back blasting surface. The attenuation law of vibration velocity of the first excavated tunnel is similar to that of the later excavated tunnel, with the fastest attenuation at the vault, followed by the arch waist. The vibration velocity peak and stress distribution of the initial support structure of the first-excavated tunnel are symmetrically distributed based on the excavation surface. Additionally, a safety-judging standard based on vibration velocity peak and tensile stress is established. It is concluded that the safe velocity for liner structures is 10. 81 cm/s, with the maximum single-stage charge amount determined to be 58. 2 kg. The research provides a reference for the safe construction of tunnels when excavating double-line tunnels simultaneously.

关 键 词：隧道工程 现场监测 数值模拟 振速峰值 动态响应 安全阈值 

分 类 号：U455.6[建筑科学—桥梁与隧道工程]