摘要
为研究深埋非圆形隧道开挖引起围岩的弹性和黏弹性变形解析解,首先通过复变函数的方法,得到了围岩中位移的弹性解。之后,根据弹性-黏弹性对应原理,采用Burgers黏弹性模型,通过拉普拉斯变换和拉普拉斯逆变换,得到围岩位移的黏弹性解。最后以Ⅳ级围岩中铁路双线隧道为例,通过搜索边界映射点的方法,得到其映射函数。给出了隧道附近的弹性位移等值线图、沿隧道边的弹性位移,及隧道拱顶、拱底和拱腰三个特殊点的黏弹性位移,并讨论了侧压系数对弹性和黏弹性位移的影响。研究结果表明:开挖引起的弹性位移在隧道附近区域迅速下降,之后缓慢趋于零;拱顶和拱底的黏弹性竖直位移、拱腰的黏弹性水平位移随时间变化明显,在5 a左右,变化速率减小;随侧压系数的增大,拱顶和拱底的弹性竖直位移减小,黏弹性竖直位移几乎未变,拱腰的弹性和黏弹性水平位移值增大。隧道开挖后,要及时支护,并注意拱顶和拱底的竖直位移。
In order to study the analytical solutions of elastic and viscoelastic displacements for rock mass caused by the excavation of deep-buried non-circular tunnel,the elastic solution to the displacement in the rock mass was first obtained by using the complex variable method.Then,the viscoelastic solution to the displacement was deduced by Laplace transform and Laplace inverse transform using the Burgers viscoelastic model based on the elastic-viscoelastic correspondence principle.Finally,in the case of the double-track railway tunnel in rock mass of gradeⅣ,the mapping function was obtained by searching the boundary mapping points.The elastic displacement contours around the tunnel,the elastic displacements along the tunnel edge,and the viscoelastic displacements at the vault,bottom and hance of the tunnel were given.The influence of lateral pressure coefficient on the elastic and viscoelastic displacements was also discussed.The research results show that the elastic displacement caused by excavation decreases rapidly near the tunnel and then tends to zero slowly.The viscoelastic vertical displacements at the vault and bottom and the viscoelastic horizontal displacement at the hance change obviously with time.After about 5 years,the change rate of viscoelastic displacement decreases.With the increase of lateral pressure coefficient,the elastic vertical displacement at the vault and bottom decreases,but the viscoelastic vertical displacement almost remains unchanged,and the elastic and viscoelastic horizontal displacements at the hance increase.After tunnel excavation,timely support of the tunnel is required,and attention should be paid to the vertical displacement at the vault and bottom.
作者
刘淑红
范金录
陈智慧
朱永全
LIU Shuhong;FAN Jinlu;CHEN Zhihui;ZHU Yongquan(Department of Engineering Mechanics,Shijiazhuang Tiedao University,Shijiazhuang 050043,China;China Railway Siyuan Survey and Design Group Co.,Ltd,Wuhan 430063,China;School of Civil Engineering,Shijiazhuang Tiedao University,Shijiazhuang 050043,China)
出处
《铁道学报》
EI
CAS
CSCD
北大核心
2022年第3期142-149,共8页
Journal of the China Railway Society
基金
国家自然科学基金(51778380)
中国国家铁路集团有限公司科技研究开发计划(N2020G040)。
关键词
复变函数
非静水应力场
非圆形隧道
BURGERS模型
黏弹性位移
complex variable function
non-hydrostatic stress field
non-circular tunnel
Burgers model
viscoelastic displacement
作者简介
刘淑红(1968—),女,辽宁北票人,教授,博士,E-mail:Liush@stdu.edu.cn。
