摘要
大角度斜交框架桥的受力空间特性复杂,盾构隧道施工对斜交框架结构内力影响有待研究。以杭州市地铁5号线盾构穿越沪昆铁路江城路立交为案例,建立了两阶段地层-结构法有限元模型,先计算盾构施工引起的路基、框架桥变形,然后使用厚壳单元计算结构内力,进而验算截面承载力。经验证,本文方法与原设计计算基本吻合,能够评估大角度斜交框架桥的空间受力状态;施工监测数据证明变形和内力计算结果准确。盾构施工引起的斜交框架桥变形曲线保持线性,但箱体不均匀沉降的主方向与盾构轴线不垂直;盾构施工加剧斜交框架桥空间受力的扭转效应,内力增幅显著;地层损失率控制得当时,盾构施工满足路基变形要求和箱形桥结构安全要求。
The spatial mechanical characteristics of large-angle skewed box culvert are very complicated,the influence of shield tunnel construction on the skewed box culvert requires further studies.A two-step FEM model was established to study the influence of shield tunnel of Hangzhou metro line 5 crossing the Jiangcheng Rd.Interchange.The first step obtains the displacement and deformation of subgrade,box culvert and railway due to shield construction,and then a thick shell element model was used to study the internal force of the box culvert;finally,the stress of reinforcement concrete was validated.The calculation method used in this paper is consistent with the original design,which can reflect the mechanical characteristic of the large-angle skewed box culvert;and the settlement calculation is verified by in-situ monitoring data.The calculation results show that the displacement of the skewed box culvert caused by shield construction is linear.However,the main developing direction of uneven settlement of the culvert is not perpendicular to the shield tunneling axis.The torsion effect of the space stress of the skew box bridge caused by shield construction is intensified,and the amplification of the internal force is apparent.With well-controlled the ground loss ratio of shield construction,the requirements of track deformation control and box bridge structure safety during shield construction can be fulfilled.
作者
刘琤玉
王炳龙
宋福贵
徐俊
韩学芳
Liu Chengyu;Wang Binglong;Song Fugui;Xu Jun;Han Xuefang(Key Laboratory of Road and Traffic Engineering of the Ministry of Education,Tongji University,Shanghai 201804,P.R.China;Shanghai Key Laboratory of Rail Infrastructure Durability and System Safety,Shanghai 201804,P.R.China;Shanghai Tongji Engineering Consulting Co.,Ltd.,Shanghai 200092,P.R.China;China Railway Shanghai Group Co.,Ltd.,Shanghai 200071,P.R.China)
出处
《地下空间与工程学报》
CSCD
北大核心
2022年第S01期318-325,共8页
Chinese Journal of Underground Space and Engineering
基金
国家自然科学基金(51778485,51608384)
关键词
铁路桥梁
空间受力
框架结构
盾构隧道
临近施工
railway bridge
spatial bearing performance
frame structure
shield tunnel
adjacent construction
