临海大断面超浅埋公路隧道侧穿敏感建筑物控爆技术  

Controlled Blasting Technology for Shallow-buried Large Section Tunnel Side Crossing Susceptible Buildings in Coastal Stratum

作　　者：李刚[1] LI Gang(China Railway 18th Bureau Group Co.,Ltd.,Tianjin 300222,China)

机构地区：[1]中铁十八局集团有限公司,天津300222

出　　处：《公路交通科技》2023年第1期160-168,共9页Journal of Highway and Transportation Research and Development

基　　金：2019年度天津市“131”创新型人才团队项目(201943)。

摘　　要：为解决城市海底隧道陆域段钻爆法施工产生的爆破振动对周边建(构)筑物结构安全及居民生活影响大的问题,依托厦门第二西通道(海沧海底)隧道工程,通过现场试验、理论计算的方法对复杂地质条件下城市浅埋暗挖隧道侧穿敏感建(构)筑物段控制爆破技术进行了优化研究,提出了建(构)筑物保护及加固方案、控制爆破辅助措施和控制爆破参数优化方案,验证了中导洞掏槽设计、炮眼及空孔布设、进尺设计等控制爆破措施的合理性,对现场试验爆破振速监控量测的数据进行了分析。结果表明:采用数码电子雷管、控制单段最大装药量、减小开挖断面尺寸、缩短进尺等控制爆破辅助措施,结合“空孔+掏心+楔形掏槽”控爆开挖方案及参数优化方案,可显著控制周边建筑物的爆破振速;当隧道近距离穿越地表建筑物时,在爆破影响区与建筑物基础间增设灌注桩、隔振桩及注浆的方式,能够起到明显的隔振和控制沉降作用;采取的控制爆破方案可有效地将隧道爆破振速控制在0.5 cm/s以内,可基本实现掌子面前方10 m地表处无感爆破,掌子面前方20 m以外地表爆破振速监测仪无触发,显著降低隧道爆破施工对周边环境的影响,保证隧道周边建(构)筑物的结构安全,为城市地下空间爆破开挖提供借鉴。In order to solve the blasting vibration caused by the construction of urban undersea tunnel in the land section by drilling and blasting method, which has great impact on the structural safety of surrounding buildings(structures) and the lives of residents, relying on the Xiamen Second West Passage(Haicang Undersea) Tunnel project, Through field test and theoretical calculation, the controlled blasting technology for the side crossing sensitive buildings(structures) of urban shallow buried tunnel under complex geological conditions is optimized by using field test and theoretical calculation. The protection and reinforcement scheme of the buildings(structures), the auxiliary measures for controlling blasting and the optimization scheme of the control blasting parameters are proposed. The rationality of the control blasting measures such as the cut design of the middle pilot tunnel, the layout of blastholes and empty holes, and the footage design are verified. The monitoring data of blasting vibration velocity in field test are analyzed. The result shows that(1) the blasting vibration velocity of surrounding buildings can be significantly controlled by using digital electronic detonators, controlling the maximum charge of single section, reducing the excavation section size, shortening the footage and other auxiliary measures to control blasting in combination with the blasting excavation scheme of “hollow hole + core cutting + wedge cutting” and the parameter optimization scheme;(2) when the tunnel crosses the surface buildings in close proximity, the way of adding cast-in-place piles, vibration isolation piles and grouting between the blasting affected area and the building foundation can play an obvious role in vibration isolation and settlement control;(3) the adopted blasting scheme can effectively control the tunnel blasting vibration velocity within 0.5 cm/s, it can basically realize the non-inductive blasting at the surface 10 m in front of the tunnel face, and the surface blasting vibration velocity

关 键 词：隧道工程 爆破控制 现场试验 钻爆法 爆破参数优化 

分 类 号：U455.4[建筑科学—桥梁与隧道工程]