摘要
依托某新建铁路深路堑路基近距离上跨既有市域铁路隧道工程,借助有限元软件MIDAS构建隧址区三维数值模型,分析隧道变形及结构受力,评估路基建设前后既有隧道结构安全性。研究表明:路基的修建引起隧址区围岩应力二次重分布,导致仰拱处最大拉应力增加0.567 MPa;上方土体开挖卸荷导致结构整体隆起变形,仰拱隆起最终变形为4.169 mm;现场监测验证了计算结果的合理性;荷载结构法表明,路基修建后下方既有结构安全系数会降低,但仍在安全规范限值之内。
Based on the project of a new railway deep cutting subgrade adjacent to upper span on the existing urban railway tunnel in proximity,MIDAS,finite element software,was used to build the three-dimensional numerical model of the tunnel site area.This model helped analyze the tunnel deformation and structural stress,and assessed the safety of the existing tunnel structure before and after the subgrade construction.The research shows that,the construction of the subgrade causes the secondary redistribution of the surrounding rock stress in the tunnel site area,which leads to the increase of the maximum tensile stress at the inverted arch by 0.567 MPa;the excavation unloading of the soil above leads to the overall uplift deformation of the structure,and the final deformation of the inverted arch is 4.169 mm.The rationality of the calculation results is verified by field monitoring.The load structure method shows that the safety factor of the existing structure below the subgrade will be reduced after the construction of the subgrade,but it is still within the safety specification limit.
作者
张云龙
许强
张治国
王毅
ZHANG Yunlong;XU Qiang;ZHANG Zhiguo;WANG Yi(Shandong Transportation Research Institute,Jinan 250102,China;The Seventh Engineering Co.,Ltd.of CTCE Group,Hefei 230061,China;Shandong Expressway Changtongdao Bridge Engineering Co.,Ltd.,Weifang 261000,Shandong,China)
出处
《路基工程》
2024年第6期70-75,共6页
Subgrade Engineering
基金
山东省自然科学基金项目(ZR2020QE269)。
关键词
深路堑路基
上跨
既有隧道
有限元计算
安全系数
deep cutting subgrade
upper span
existing tunnel
finite element calculation
safety factor
