摘要
针对内张钢圈加固后的盾构管片结构,现有研究中多基于理想界面假设,忽略了钢-混凝土连接界面非连续变形特性,无法对结构的承载性能和破坏机制做出精细分析。将内聚力模型与扩展有限元方法相结合,考虑了加固结构连接界面的非连续变形特性,建立了可精确描述裂缝扩展过程的内张钢圈加固结构三维实体非线性模型,并利用足尺试验结果验证了计算的正确性,实现了钢与混凝土两种不同材料连接界面滑移破坏及开裂等劣化行为的动态模拟,弥补了试验的不足。在此基础上,对顶部超载与地层荷载作用下加固结构的力学性能展开分析,研究结果表明:顶部超载作用下加固结构受力破坏过程主要分为4个阶段,钢圈与混凝土连接界面处裂缝的扩展与黏结破坏是结构失稳破坏的决定性因素;地层荷载作用下加固结构受力过程中,连接界面接头处存在拉—压交替的非协调变形区域,易发生剪切滑移及剥离破坏。
To investigate the properties of the structure of segmental tunnel linings reinforced by steel plates,most of the existing studies assume that the interfaces between different materials are perfectly bonded,and thus ignore the discontinuous deformation characteristics of the steel-concrete interface,and then it is impossible to make a detailed analysis of the load-bearing behavior and failure mechanism of a structure.In this work,the cohesive-zone model is combined with the extended finite element method,and the discontinuous deformation characteristics of the connecting interface of the steel-plate-reinforced structure are considered.At the same time,a three-dimensional solid nonlinear model for the steel-plate-reinforced structure that can accurately describe the crack propagation process is established,and is validated through the tests.The dynamic simulation of the sliding failure and cracking of the interface between two different materials of steel and concrete is carried out,which makes up for the shortcomings of the tests.Thus,the mechanical properties of the reinforced structure under surface surcharge are analyzed.The results show that the stress failure process of the reinforced structure under surface surcharge can be divided into four stages.The cracking and bond failure of connecting interface between the steel plates and the concrete are the decisive factors for the failure of the reinforced structure.Under the action of the ground load,at the connecting interface joint of the reinforced structure,there are incompatible deformation areas with alternative tension and compression,which is more prone to shear slip and peel failure.
作者
孙雅珍
于阳
王金昌
叶友林
谭清元
SUN Ya-zhen;YU Yang;WANG Jin-chang;YE You-lin;TAN Qing-yuan(School of Transportation Engineering,Shenyang Jianzhu University,Shenyang 110168,China;School of Civil Engineering,ShenyangJianzhu University,Shenyang 110168,China;Institute of Transportation Engineering,Zhejiang University,Hangzhou 310058,China)
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2022年第2期343-351,I0008,F0003,共11页
Chinese Journal of Geotechnical Engineering
基金
国家重点基础研究发展计划(“973”计划)项目(2015CB057801)
辽宁省自然科学基金项目(2018011666-301)。
关键词
盾构隧道
内张钢圈加固
数值计算
连接界面
内聚力模型
扩展有限元
shield tunnel
steel-plate reinforcement
numerical calculation
connecting interface
cohesive-zone model
extended FEM
