大断面黄土隧道下穿地表建筑物沉降分析及对策  

Analysis and countermeasures of surface settlement of buildings undercrossing large section loess tunnels

作　　者：赵启超 Zhao Qichao(China Railway First Survey And Design Institute Group Co.,Ltd.,Xi’an Shaanxi 710043,China)

机构地区：[1]中铁第一勘察设计院集团有限公司,陕西西安710043

出　　处：《山西建筑》2025年第3期130-134,140,共6页Shanxi Architecture

基　　金：中铁第一勘察设计院集团科研项目(院科17-26)。

摘　　要：依托西延高铁某黄土隧道下穿地表建筑物工程实例,采用理论分析、数值模拟等手段,对大断面黄土隧道下穿地表建筑物施工中地表沉降范围及对策进行研究。结果表明:基于随机介质理论,隧道两侧的地表沉降范围可划分为强、弱、无影响区,隧道施工对地表强影响区范围约等于隧道埋深,弱影响区范围约为隧道埋深的2倍;在开挖面到达办公楼正下方时办公楼沉降值约占总沉降值的70%;穿过办公楼后,沉降速率趋于收敛,隧道施工中接近地表建筑物要加强施工质量,保证地表结构安全;隧道通过地表建筑物后,地表沉降趋于收敛,但沉降值仍不断增大,隧道穿越地表建筑物后,应持续开展建筑物沉降变形监测,掌子面二衬紧跟,保证地表建筑物结构安全;大断面黄土隧道下穿地表建筑物时,采用三台阶临时仰拱(腰梁)法、锁脚加强、初支加强等措施后,可保证隧道施工安全,相关措施可为相类似工程的施工提供借鉴意义。This article is based on an engineering example of a loess tunnel passing through the surface of a building(structure)on the West Extension High Speed Railway,using theoretical analysis,numerical simulation and other methods,this study investigates the range and countermeasures of surface settlement during the construction of large-section loess tunnels passing through surface buildings.The results indicate that:Based on the theory of random media,the surface settlement range on both sides of the tunnel can be divided into strong,weak,and no impact zones.The strong impact zone of tunnel construction on the surface is approximately equal to the depth of the tunnel,while the weak impact zone is about twice the depth of the tunnel;When the excavation surface reaches directly below the office building,the settlement value of the office building accounts for about 70%of the total settlement value;After passing through the office building,the settlement rate tends to converge.During tunnel construction,it is necessary to strengthen the construction quality of buildings(structures)close to the surface to ensure the safety of the surface structure;After the tunnel passes through the surface buildings,the surface settlement tends to converge,but the settlement value continues to increase.After the tunnel passes through the surface buildings,the settlement deformation of the buildings should be continuously carried out,and the second lining of the palm face should follow closely to ensure the structural safety of the surface buildings;When a large cross-section loess tunnel passes through surface buildings,measures such as the three step temporary arch(waist beam)method,locking foot reinforcement,and initial support reinforcement can be adopted to ensure the safety of tunnel construction.These measures can provide reference significance for the construction of similar projects.

关 键 词：大断面黄土隧道 建筑物 地表沉降 影响区 

分 类 号：TU997[建筑科学—市政工程] U455[建筑科学—桥梁与隧道工程]