摘要
由于围岩性质多变且土体-衬砌接触复杂,为探明既有隧道荷载计算理论及修正惯用法荷载体系是否能较好契合不同埋深下的砂性地层盾构隧道,依托南昌地铁盾构隧道建立了弹塑性有限元模型,采用罚函数算法模拟土体–衬砌结构接触面。同步开展了几何相似比为1:10的模型试验以修正有限元模型。再进一步深入研究不同埋深下衬砌荷载大小及分布模式,并与全土柱法、太沙基理论、谢家烋理论计算值对比。结果表明:衬砌所受荷载整体呈“花生形”分布,荷载大小从拱顶附近逐渐减小至拱腰,再从拱腰增大至拱底;衬砌竖向荷载分布形态类似正态分布函数,水平荷载分布形态近似抛物线;埋深为1~3倍洞径时,衬砌竖向荷载按太沙基理论计算更为合适;埋深大于3倍洞径时,太沙基理论计算值略偏不安全,而谢家烋理论计算值则偏保守。
In order to find out whether the existing tunnel load calculation theory and the load system of modified routine method can better fit the shield tunnel in sandy stratum under different buried depths due to the variable nature of surrounding rock and the complex contact between soil and lining, the elastic-plastic finite element model was established based on Nanchang metro shield tunnel, and the penalty function algorithm was adopted to simulate the soil-lining structure interface. A model test with geometric similarity ratio of 1:10 was carried out synchronously to correct the finite element model. Then the load size and distribution mode of shield tunnel lining in sand ground was studied further under different buried depths, and compared with the calculated values of the whole soil column method,Terzaghi theory and Xie Jiaxiu theory. The results show that the overall load distribution of the lining is “peanut-shaped”,and the load decreases gradually from the vault to the arch waist, and then increases from the arch waist to the arch bottom. The vertical load distribution of lining is similar to the normal distribution function, and the horizontal load distribution is approximately parabolic. When the buried depth is from 1 to 3 times the hole diameter, the vertical load of the lining is more suitable according to the Terzaghi theory. When the buried depth is greater than 3 times the hole diameter, the calculation based on Terzaghi theory is slightly unsafe, while the calculation based on Xie Jiaxiao theory is conservative.
作者
张涛
石钰锋
周宇航
钟广
熊金平
胡梦豪
ZHANG Tao;SHI Yufeng;ZHOU Yuhang;ZHONG Guang;XIONG Jinping;HU Menghao(Jiangxi Key Laboratory of Infrastructure Safety Control in Geotechnical Engineering,East China Jiaotong University,Nanchang 330013,China;Jiangxi Underground Space Technology Development Engineering Research Center,Nanchang 330013,China;Nanchang Urban Rail Group Co.,Ltd.,Nanchang 330038,China;Nanchang Orbital Housing Bridge Building Materials Co.,Ltd.,Nanchang 330096,China)
出处
《建筑结构》
CSCD
北大核心
2022年第S02期2682-2688,共7页
Building Structure
基金
国家自然科学基金面上项目(42177162)
江西省交通运输厅科技项目(2020Z0001)
关键词
衬砌荷载
模型试验
数值模拟
接触面
埋深
lining load
model test
numerical simulation
interface
burial depth
作者简介
第一作者:张涛,硕士研究生,主要从事隧道与地下工程研究,Email:zt04200305@163.com;通信作者:石钰锋,博士,副教授,主要从事隧道预加固、长期变形研究,Email:s074811156@126.com。
