摘要
研究目的:为解决在建兰渝铁路高地应力软岩隧道大变形问题,针对其地质条件复杂和影响因素多变的特点,提出在隧道断面内设置超前小导洞的方案,利用小导洞的可变形性,将地层高地应力提前释放,使正洞开挖时处于可接受的相对低应力状态。本文采用数值模拟的方法确定了合理的超前导洞位置、尺寸与断面形状。研究结论:以毛羽山隧道为研究对象,采用有限差分程序对超前导洞不同位置、尺寸及断面形状等工况的释放率分别进行了数值模拟,考虑施工组织、工程造价以及释放效果等综合因素,确定出了合理的断面形状与导洞位置,即导洞尺寸为:7.6 m(宽)×5.5 m(高),导洞拱顶距正洞拱顶距离为2.5 m。对应正洞A、BB'、CC'、DD'释放率分别为37%、54%、72%和59%。可为其他类似工程的施工与设计提供参考依据。
Research purposes ： In order to solve the problem of the large deformation in high geo - stress tunnel of ongoing lanzhou - chongqing railway, according to the characteristic of the complex geological conditions and changeable influencing factors, the high in - situ stress in the right hole was released in advance by using deformability of the super pilot tunnel, under these conditions, the right hole was in acceptable low - stress state when it was excavated, which was potengoally less the input of support rigidity. This paper determined reasonable by using numerical simulation method.Research conclusions：By taking maoyushan tunnel as the research object, the displacement release rate corresponding various location and dimension of the super pilot tunnel was studied in the paper through numeric simulation. The two - dimensional analysis show that the reasonable dimension of the super pilot tunnel was 7.6m （width） × 5.5 m （height）. The reasonable distance between the pilot tunnel vault and the right holt vault was 2.5m. The displacement release rate fo A snd BB＇and CC＇and DD＇were respevtively 37%, 54% ,72% and 59%. This paper can provide reference for construction and design of other similar projects.
出处
《铁道工程学报》
EI
北大核心
2011年第9期58-62,共5页
Journal of Railway Engineering Society
基金
中国铁道科学研究院院基金项目(10SKL123T124)
关键词
高地应力
软岩
应力释放
断面优化
释放率
high ground stress
soft rock
stress releasing
section optimization
release rate
