摘要
宝兰客运专线二沟墩黄土隧道按原设计施工出现拱顶沉降速率加快、初期支护拱部裂缝等问题,对该隧道下穿沟谷浅埋段原设计的超前加固和初期支护参数进行了优化,并对优化前后施工过程中隧道内典型断面的围岩变形数据进行了对比分析。结果表明:在1.5倍断面宽度处超前中管棚开始发挥很好的支护作用;在加强超前加固和支护的条件下,对于断面宽度>13 m的大断面黄土隧道封闭成环初期支护断面距掌子面的距离控制在20 m以内能够保障施工安全。
There are such issues as the quickening crown settlement speed and arch fracture ofinitial support according to the original design and construction in Ergoudun loess tunnel of Baoji-Lanzhou passenger dedicated line. The original designed advanced reinforcement and initial support parameters of shallowburied section where tunnel crosses underneath the gulch were optimized,and surrounding rock deformation data of typical tunnel section during the construction process were compared and analyzed before and after optimization. The results showthat advanced middle pipe shed plays a good supporting role at the position which is 1. 5 times the width of the section,and the distance fromthe closed ring initial support section to working face should be less than 20 mto ensure construction safety for large section loess tunnel with section width that is greater than 13 m.
出处
《铁道建筑》
北大核心
2017年第5期76-78,共3页
Railway Engineering
关键词
铁路隧道
施工安全
现场试验
黄土隧道
地质勘探
设计优化
Railway tunnel
Construction safety
Field test
Loess tunnel
Geologic survey
Design optimization
