软土地区双线盾构下穿机场跑道沉降规律研究  

Research on the Settlement Regularity of Double-line Shield Tunnels Underneath Passing through Airport Runways

作　　者：焦忺玥 董秀竹 林森斌 JIAO Xianyue;DONG Xiuzhu;LIN Senbin(China Railway Design Corporation,Tianjin 300142,China)

机构地区：[1]中国铁路设计集团有限公司,天津300142

出　　处：《铁道工程学报》2024年第2期68-73,共6页Journal of Railway Engineering Society

基　　金：中国铁路设计集团有限公司科技开发课题(2020YY330317)。

摘　　要：研究目的:本文依托天津地铁Z2线下穿滨海机场工程,在考虑机场不停航的情况下,对软土地区双线盾构隧道下穿机场飞行区引起的跑道沉降进行分析,探究盾构埋深及深孔注浆圈厚度对跑道沉降的影响,以得到合适的盾构埋深及深孔注浆圈厚度,并深入分析其对跑道沉降影响的规律特性。研究结论:(1)增大盾构隧道覆土厚度和管片周围深孔注浆圈厚度能有效地减小跑道沉降及差异沉降率,但对沉降的减小效果并非随注浆圈厚度增加而愈加有效;(2)双线隧道开挖完成后,道面横向沉降曲线呈现“V”形沉降槽,由于前后线施工叠加效果,最大沉降位置偏向后施工隧道一侧;(3)同一埋深下,后线施工对跑道最大沉降的影响小于前线隧道对跑道沉降的影响,且随着注浆圈厚度的增加,后线施工对跑道沉降的影响越来越小;(4)随着双线隧道先后掘进,机场道面的差异沉降率呈现先增大、再减小的趋势,后趋于稳定;(5)本研究结论可为软土地区双线盾构下穿机场跑道类似工程中的盾构埋深及深孔注浆设计提供参考依据、施工指导。Research purposes:This paper relies on the project of the tunnel of Tianjin Metro Z2 underneath passing through the Binhai Airport,considering the airport non-stop flighting,analyzes the deformation of the runways of airport flight area caused by double-line shield tunnels undercrossing in the soft soil area,and explores the effects of shield burial depth and deep hole grouting circle thickness on the sedimentation of the runway,to obtain a suitable shield burial depth and deep hole grouting circle thickness,and analyzes its regularity on the sedimentation of the runway,providing guidance for the construction of double-line shield tunnels undercrossing non-stop airport runway in the soft soil area.Research conclusions:(1)Increasing shield burial depth and deep hole grouting circle thickness can effectively reduce the settlement and the rate of difference settlement of the runway,but the reduction effect on the settlement does not become more effective with the increase of deep hole grouting circle thickness.(2)After the double-line tunnel excavation is completed,the horizontal settlement curve of the runways presents the"V"shape.Because of the stacking effect of doubleline shield tunnels successive construction,the maximum settlement position is closer to the tunnel of the later excavation.(3)At the same buried depth,the influence of the tunnel of the later excavation on the settlement of the runway is less than the impact of the tunnel of the first excavation on it,and with the increase of the thickness of the grouting circle,the impact of the tunnel of the later excavation on the settlement of the runway is getting smaller and smaller(.4)During the doubleline tunnel excavation,the rate of difference settlement of the runway increases,and then decreases,and finally stabilizes.(5)The research result provides a reference and construction guidance for the shield burial depth and deep-hole grouting design in the project of double-line shield tunnel undercrossing airport runways in the soft soil area.

关 键 词：软土 双线盾构隧道 下穿机场跑道 不停航 注浆圈厚度 沉降规律 

分 类 号：U452.27[建筑科学—桥梁与隧道工程]