摘要
采用三维有限元数值分析,结合某工程隧道下穿既有管线案例,研究不同下穿角度对地层及既有管线的沉降变形影响。研究分析表明,隧道仰拱处均发生明显隆起,地层竖向沉降较大处主要集中在隧道拱部上方,且不同夹角对隧道开挖引起的地层竖向变形范围和沉降数值影响不大;随着施工阶段的进行,管线沉降逐渐变大,最大沉降位置发生在隧道正上方,随着隧道与既有管线夹角的增大,管线两侧沉降变形的不对称性逐渐减弱,当两者夹角为90°,即两者完全正交时,两侧沉降变形完全对称;隧道不同下穿角度对距离隧道相同水平距离位置处的沉降变形影响基本可以忽略,且从两侧向中间呈现先缓慢沉降、后快速沉降的变形规律,但管线沿自身方向同一位置处的沉降变形随着二者夹角的减小而增大,既有管线整体沉降变形增大。
Using three-dimensional finite element numerical analysis,combined with the case of the existing pipeline under the tunnel of a certain project,the influence of different underpassing angles on the settlement deformation of the formation and the existing pipeline was studied in this paper.The research and analysis shows that:Obvious uplift occurs at the tunnel arch,and the vertical settlement of the formation is mainly concentrated above the tunnel arch,and the different angles have little impact on the range and settlement value of the vertical deformation of the formation caused by tunnel excavation.Along with the construction stage,the pipeline settlement gradually becomes larger,the maximum settlement position occurs directly above the tunnel,with the increase of the angle between the tunnel and the existing pipeline,the asymmetry of the settlement deformation on both sides of the pipeline gradually weakens,when the angle is 90,that is,when the two are completely orthogonal,the settlement deformation on both sides is completely symmetrical.The impact of different tunnel underpassing angles on the settlement deformation at the same horizontal distance from the tunnel can be basically ignored,and the deformation law of first slow settlement and then rapid settlement are presented from both sides to the middle.However,the settlement deformation of the pipeline at the same position along its own direction increases with the decrease of the angle,and the overall settlement deformation of the existing pipeline increases.
作者
孙壮壮
Sun Zhuangzhuang(Bridge and Tunnel Design Institute of the First Survey and Design Institute Group Co.Ltd.of China Railway,Xi’an 710000,China)
出处
《石家庄铁道大学学报（自然科学版）》
2022年第3期92-97,共6页
Journal of Shijiazhuang Tiedao University(Natural Science Edition)
关键词
隧道工程
有限元分析
城市管线
下穿隧道
tunnel engineering
finite element analysis
urban pipeline
underneath tunnel
