摘要
黄土具有显著各向异性,渗透性强,多具湿陷性等特点。以可乐湾黄土隧道工程为依托,通过原状黄土物理特性试验、固结压缩与湿陷性试验和原状黄土三轴抗剪试验,深入探究工程区原状黄土的各向异性及变形特征。利用数值模拟有限元软件,在不同开挖方法、不同超前小导管长度、不同锁脚锚管长度及地表注浆的条件下,对比分析了黄土隧道施工中沉降变形趋势。结果表明:1)黄土的水平和竖直方向力学指标有明显差异,水平方向天然压缩模量大于竖直方向;2)综合考虑各种因素,建议采用二台阶五步法施工,辅助4.5 m的超前小导管及5 m的锁脚锚管;3)地表注浆对隧道及石油管道的沉降变形的保护作用效果不明显。
Loess is characterized by significant anisotropy,high permeability and wet sinkability.In this paper,the anisotropy and deformation characteristics of in-situ loess in the project area were investigated by physical properties test,consolidation compression,wet sink test and triaxial shear test of in-situ loess based on Coke Bay loess tunnel project.Using numerical simulation finite element software,the settlement deformation trend in the construction of loess tunnel was compared and analyzed under the conditions of different excavation methods,different lengths of overrunning small conduits,different lengths of locking foot anchor tubes and surface grouting.The results show that:1) there are obvious differences between the mechanical indexes of loess in vertical and horizontal directions,and the natural compression modulus in vertical direction is smaller than that in horizontal direction;2) considering various factors,it is recommended to use two-step and five-step construction method assisted by 4.5 m of overrunning small conduit and 5 m of locking foot anchor pipe;3) the protective effect of surface grouting on settlement deformation of tunnel and oil pipeline is not obvious.
作者
杨晓光
刘红林
穆腾虎
陈贤丰
李德武
YANG Xiaoguang;LIU Honglin;MU Tenghu;CHEN Xianfeng;LI Dewu(CCCC Road Bridge North China Engineering Co.,Ltd,Beijing 101100,China;School of Civil Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China;China Railway Eryuan Engineering Group Co.Ltd,Chengdu 610031,China)
出处
《兰州交通大学学报》
CAS
2024年第6期107-114,共8页
Journal of Lanzhou Jiaotong University
基金
中交路桥建设有限公司2020年科技计划项目(2020-010)。
关键词
黄土隧道
各向异性
变形
数值模拟
注浆
loess tunnel
anisotropy
deformation
numerical simulation
grouting
