小净距下穿引水隧洞施工技术方案应用与研究

Application and Research of Construction Technology Scheme of New Tunnel Crossing Diversion Tunnel at Close Distance

结合皂李湖—白马湖输水隧洞小净距下穿寒天岗隧洞实例,通过对隧洞交叉控制段采用超前管棚支护、导洞先行、分层分段毫秒(半秒)延时微差爆破技术、限制单段爆破最大用量及围岩安全监测等工程措施,可有效降低新建隧洞爆破开挖产生的震动影响范围,保证既有隧洞结构安全稳定,对类似工程有很好的借鉴作用。

Combined with the example of the Zaoli-Baima Lake water transmission tunnel passing through the Hantiangang tunnel at close range,by adopting engineering measures to the tunnel crossing control section,such as advanced pipe shed support,pilot tunnel first,layered segmented millisecond(half second)delay micro-difference blasting technology,limiting the maximum amount of single-stage blasting and surrounding rock safety monitoring,the vibration impact range caused by the blasting excavation of the new tunnel can be effectively reduced and the safety and stability of the existing tunnel structure can be guaranteed.It has a good reference value for similar projects.