摘要
基于叙永—毕节铁路酸草树隧道,通过三维数值模拟分析变截面隧道施工过程中支护结构的力学特性,探讨变截面段的合理施工过渡方式及支护参数。结果表明:变截面隧道的施工过渡方式,应由大断面段往小断面段方向进行,大断面段可采用双侧壁导坑法开挖,超前大管棚支护;支护参数变化主要影响隧道水平横向变形,其对初期支护强度等级变化尤为敏感;超前大管棚衔接长度是施工优化的关键参数,适当增长过渡段衔接的大管棚长度可有效降低隧道的变形量,尤其是隧道轴向变形;施工中应重点关注大断面段近变截面一侧的左右拱腰位置,此处极易发生竖向压溃破坏。
Based on the Suancaoshu Tunnel of Xuyong—Bijie Railway,this paper,through three-dimensional numerical simulation,analyzed the mechanical properties of the supporting structure during the construction of the variable crosssection tunnel,and discussed the reasonable construction transition mode and supporting parameters of the variable crosssection section.The result shows that,the transition of the variable cross-section tunnel shall be made from the large section section to the small section section.The large section section can be excavated by the double side heading method and supported with advanced large pipe sheds.The change of support parameters mainly affects the horizontal lateral deformation of tunnel,which is particularly sensitive to the change of initial support strength grade.The connection length of the advanced large pipe shed is a key parameter for construction optimization.Appropriately increasing the length of the large pipe shed connected to the transition section can effectively reduce the deformation of the tunnel,especially the axial deformation of the tunnel.In the construction,attention shall be paid to the position of the left and right arch waist on the side near the variable cross section of the large section section,where the vertical crush failure is liable to occur.
作者
郭德平
刘语泉
黄兴
GUO Deping;LIU Yuquan;HUANG Xing(Xuzhen Railway Co.,Ltd.,Luzhou 646699,Sichuan,China;Key Laboratory of Transportation Tunnel Engineering(Ministry of Education),Southwest Jiaotong University,Chengdu 610031,China;China Railway Design Co.,Ltd.,Tianjin 300142,China)
出处
《路基工程》
2025年第3期175-181,共7页
Subgrade Engineering
关键词
铁路隧道
变截面
力学特性
敏感性分析
过渡方式
railway tunnel
variable cross-section
mechanical properties
sensitivity analysis
transition mode
