摘要
昔格达地层是分布于我国攀西地区的一种特殊半成岩,具有孔隙比大、粘结力差、水稳性差等特点.本文以米攀铁路攀枝花段冉家湾隧道为工程依托,以严格控制地层及地面建筑物的沉降和变形为目的,对昔格达地层隧道下穿既有建筑物施工技术展开研究.结果表明,昔格达地层大断面铁路隧道采用大管棚超前支护和三台阶七步开挖法可安全下穿既有建筑物,沉降最大值为84.19 mm;增大锁脚锚杆支护参数、保证注浆质量,可以更好地控制地表建筑物沉降.
The Xigeda strata is a special semi-diagenetic rock distributed in the Panxi area of China.It has the characteristics of large porosity,poor cohesion,and poor water stability.On the basis of the Ranjiawan Tunnel in Panzhihua section of Mipan Railway,this paper studied the construction technology of the tunnel in Xigeda stratum under-passing existing buildings with the purpose of strictly controlling the settlement and deformation of strata and ground buildings.The research results show that the large-section railway tunnel in Xigeda stratum safely passes through the existing building with a large pipe shed advanced support and three-step seven-step excavation method,and the maximum settlement is 84.19 mm.The grouting quality can be guaranteed by increasing the supporting parameters of feet-lock anchor bolt,so as to better control the settlement of the ground surface building.
作者
王义春
WANG Yichun(China Railway 23rd Bureau Group Co.Ltd.,Chengdu Sichuan 610072,China)
出处
《铁道建筑技术》
2020年第6期128-131,136,共5页
Railway Construction Technology
基金
中国铁建股份有限公司科技研发计划项目(17-C23)。
关键词
昔格达地层
铁路隧道
下穿建筑物
三台阶七步法
大管棚
Xigeda strata
railway tunnel
under-passing the building
three-bench seven-step excavation method
large pipe shed
