无中导连拱隧道爆破振动减振对策研究  

Research on Vibration Reduction Measures of Double Arch-tunnel Without Middle Drift

作　　者：陈焕美 苏文煊 孟德生 廖明进[4] CHEN Huanmei;SU Wenxuan;MENG Desheng;LIAO Mingjing(Yunnan transportation development investment Co.Ltd.,Kunming 650000,China;Zhongjian Tunnel Engineering(Guangdong)Co.Ltd.,Guangzhou 510630,China;Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan 430071,China;School of Science,Wuhan University of Science and Technology,Wuhan 430081,China)

机构地区：[1]云南交发咨询有限公司,昆明650000 [2]中坚隧道工程(广东)有限公司,广州510630 [3]中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室,武汉430071 [4]武汉科技大学理学院,武汉430081

出　　处：《武汉理工大学学报（交通科学与工程版）》2024年第6期1205-1210,共6页Journal of Wuhan University of Technology（Transportation Science & Engineering）

基　　金：云南省交通运输厅科技创新及示范项目(云交科教[2019]79号)。

摘　　要：文中依托云南勐绿高速公路无中导连拱隧道,建立数值模型,分析后行洞爆破开挖的最大单段药量、段间延时、减振材料的布置方式和隔振岩柱厚度对围岩损伤、先行洞振动速度及衬砌位移的影响,结合现场实际情况提出建议参数.结果表明:(1)建议后行洞爆破开挖时采用分步序分段爆破方式,最大单段药量控制15 kg以内;(2)为了消除雷管起爆时间存在误差、爆破器材性能和爆破工艺的差异等影响,建议段间延时为100 ms;(3)减振层布置于初支的钢拱架和初喷混凝土之间可以显著降低衬砌振速和位移,建议在现场施工可行的情况下按照此方式布设减振层;(4)随着隔振岩柱厚度的增加,先行洞支护变形逐渐减小,衬砌速度呈现先减小后增加的变化过程,并在岩柱厚度1.5 m时达到最小值,建议隔振岩柱厚度取1.5 m.研究过程和结果可为类似工程开展现场施工提供指导和建议.Based on the multi-arch tunnel of Menglu Expressway in Yunnan,a numerical model was established.The influences of the maximum single-segment explosive charge,inter-segment delay,arrangement of vibration-damping materials and thickness of vibration-damping rock column on surrounding rock damage,vibration velocity of previous tunnel and lining displacement were analyzed,and the suggested parameters were put forward in combination with the actual situation on site.The results show that:(1)It is suggested that the blasting method of step-by-step sequence should be adopted in the subsequent tunnel blasting excavation,and the maximum single-stage charge should be controlled within 15 kg.(2)In order to eliminate the influence of the error of detonator initiation time,the difference of blasting equipment performance and blasting technology,it is suggested that the interval delay be 100 ms.(3)Arranging the damping layer between the initial steel arch and the initial sprayed concrete can significantly reduce the vibration speed and displacement of the lining,so it is suggested to arrange the damping layer in this way when the site construction is feasible.(4)With the increase of the thickness of the isolation rock column,the deformation of the first tunnel support gradually decreases.The lining speed first decreases and then increases,and reaches the minimum value when the thickness of rock column is 1.5 m.It is suggested that the thickness of vibration isolation rock column should be 1.5 m.The research process and results can provide guidance and suggestions for the field construction of similar projects.

关 键 词：无中导连拱隧道 最大单段药量 段间延时 减振层 隔振岩柱 

分 类 号：U455.4[建筑科学—桥梁与隧道工程]