跨溶岩区域隧道施工围岩稳定性研究  

Study on Stability of Surrounding Rock in Tunnel Construction Across Karst Region

作　　者：李春 LI Chun(Guangxi Transportation Science&Technology Group Co.,Ltd.,Nanning,530007 China)

机构地区：[1]广西交科集团有限公司,广西南宁530007

出　　处：《粉煤灰综合利用》2023年第3期24-30,共7页Fly Ash Comprehensive Utilization

基　　金：广西科学研究与技术开发计划项目(桂科攻1355008-3)。

摘　　要：为研究跨溶岩区域隧道位于掌子面前方的溶洞在隧道开挖过程中对隧道的影响规律,本文依托吾排隧道实际工程,利用FLAC 3D软件进行数值建模与计算,分析不同围岩级别、溶洞水压下隧道围岩在施工过程中的稳定性影响规律,得到以下结论:(1)在隧道开挖过程中,围岩级别越高,相同开挖步对应的最大主应力与最小主应力值越大,围岩的变形位移值越小;溶洞水压越大,相同开挖步对应的最大主应力与最小主应力值越大,围岩的变形位移值越大。(2)拱顶位置处的应力在开挖前期小幅波动,而后迅速增大再急剧减小,墙脚位置处的主应力值在开挖前期保持相对稳定,而后变化率逐渐增大,仰拱位置处主应力值在开挖前期基本保持不变,然后急剧增长;拱顶、仰拱位置处的位移在前期缓慢增加,开挖到一定深度时开始急剧增长。In order to study the influence law of the cavern in front of the palm face of the tunnel in the tunnel excavation process,this paper relies on the actual project of the Wupai tunnel,and uses FLAC 3D software for numerical modeling and calculation to analyze the stability influence law of the tunnel surrounding rock in the construction process under different rock levels and cavern water pressure,and obtains the following conclusions:(1)In the tunnel excavation process,the higher the level of the surrounding rock,the greater the maximum principal stress and minimum principal stress values corresponding to the same excavation step,the smaller the deformation and displacement values of the surrounding rock;the greater the cavern water pressure,the greater the maximum principal stress and minimum principal stress values corresponding to the same excavation step,the greater the deformation and displacement values of the surrounding rock.(2)The stress at the top of the arch fluctuates slightly at the beginning of the excavation,then increases rapidly and then decreases sharply;the primary stress at the foot of the wall remains relatively stable at the beginning of the excavation,then the rate of change increases gradually;the primary stress at the back of the arch remains unchanged at the beginning of the excavation,then increases sharply;the displacement at the top of the arch and back of the arch increases slowly at the beginning,then starts to increase sharply when the excavation reaches a certain depth.

关 键 词：跨溶岩区域隧道 围岩稳定性 数值计算 FLAC 3D 

分 类 号：U455[建筑科学—桥梁与隧道工程]