缓倾围岩隧道底鼓变形规律及整治措施研究  

Research on the Deformation Regularity and Treatment Measures of Tunnel Floor Heave in Gently Inclined Layered Surrounding Rock

作　　者：黄华[1] 喻渝[1] 杨昌宇[1] 朱勇[1] 邸成[1] 郑伟[1] HUANG Hua;YU Yu;YANG Changyu;ZHU Yong;DI Cheng;ZHENG Wei(China Railway Eryuan Engineering Group Co.Ltd,Chengdu,Sichuan 610031,China)

机构地区：[1]中铁二院工程集团有限责任公司,成都610031

出　　处：《铁道工程学报》2021年第4期72-78,共7页Journal of Railway Engineering Society

基　　金：中国国家铁路集团科技研究开发计划重大项目(K2019G042)。

摘　　要：研究目的:随着我国高速铁路发展,无砟轨道得到大量应用,近十年来部分隧道局部段落出现底鼓,其中一些隧道采取措施后变形得以控制,但有个别隧道采取措施后变形仍在持续,因此有必要对隧道底鼓变形规律、基底荷载及整治措施进行研究。研究结论:(1)《铁路隧道设计规范》中的荷载模式不适用于缓倾层状围岩底鼓段,本文提出了仰拱受力的力学模型;(2)仰拱底鼓量随着围岩变差而增大;随着仰拱跨度增加,呈现出非线性增大,跨度越大,增加的速率越快;随着隧底荷载增加,总体呈现出线性增加;随着衬砌厚度增加,呈现出减小趋势,厚度越大减小幅度越小;随着矢跨比增大而减小,矢跨比越大减小幅度越小,合理矢跨比为1/8~1/4;(3)当隧道底鼓段隧底荷载难以确定时,可通过隧底结构变形进行荷载反演;(4)预防或防治隧道底鼓,应从降低二衬仰拱结构承受荷载及提高承载能力两方面考虑,可采取加强衬砌隧底排水、适当加大矢跨比、加强仰拱结构、加强填充刚度等措施;(5)本研究成果可为分析隧道底鼓变形规律、研究基底荷载、确定整治措施提供理论依据。Research purposes:With the development of China’s high-speed railway,ballastless track has been widely used.In recent ten years,some tunnels have experienced floor heave in some sections.After some measures are taken,the deformation of some tunnels is under control,but the deformation of few tunnels still continued.Therefore,it is necessary to study the deformation regularity,bottom load and treatment measures of tunnel floor heave.Research conclusions:(1)The load mode in Code for Design of Railway Tunnel is not suitable for tunnel floor heave section in gently inclined layered surrounding rock,and then the mechanical model of inverted arch is put forward.(2)The floor heave of inverted arch increases with the weaken of surrounding rock;the floor heave increases nonlinearly with the increase of invert span,and the larger the span,the faster the increase rate;the floor heave increases linearly with the increase of tunnel bottom load;the floor heave decreases with the increase of lining thickness,and the larger the thickness,the smaller the reduction;the floor heave decreases with the rise to span ratio,the larger the rise span ratio,the smaller the reduction,the reasonable rise span ratio is 1/8~1/4.(3)When it is difficult to determine the tunnel bottom load of the tunnel in floor heave section,the load inversion can be carried out through the deformation of the tunnel bottom structure.(4)In order to prevent the tunnel floor heave,reducing the load and improving the bearing capacity of the secondary lining invert structure should be considered,and the measures such as strengthening the drainage of lining in tunnel bottom,properly increasing the rise span ratio,strengthening the inverted arch structure and strengthening the filling stiffness can be taken.(5)The research results can provide a theoretical basis for the deformation regularity of the tunnel floor heave,the bottom load and the treatment measures.

关 键 词：隧道底鼓 变形规律 合理矢跨比 基底荷载 整治措施 

分 类 号：U25[交通运输工程—道路与铁道工程]