摘要
准确预测隧道开挖引起的地层变形对保障施工安全非常关键。依托厦门地区典型风化花岗岩地层的盾构隧道工程,以土性参数的空间变异性为切入点,针对多层土双线盾构隧道施工地层变形问题,基于随机场理论,采用蒙特卡洛策略和有限差分模拟计算相结合的方法,开展地层变形随机分析。以土体弹性模量E的空间变异性效应为研究重点,系统研究土体弹性模量的竖向、水平波动距离(zθ,xθ)及其变异系数(COV)对双线盾构隧道施工地层变形的影响。结果表明:弹性模量变异系数对变形的影响明显强于波动距离的影响;各向异性系数(/)x zξθθ取值小于32时,地层变形对ξ的敏感性较大;地表沉降变形曲线的特征与隧道上方土体模量的随机分布密切相关。在此基础上,综合考虑低刚度占优效应和模量概率分布形式的影响,提出厦门地区盾构隧道工程设计计算的土体弹性模量等效特征建议值。
The safety of shield tunnel construction requires the proper estimation of surrounding soil deformation. The random field theory together with the finite difference analysis and Monte Carlo simulation are used to carry out the stochastic analysis on the surrounding soil deformation induced by twin tunneling in multi-layer soils considering the spatial variability of soils. The effects of scales of fluctuation（SOF） of Young＇s modulus in both vertical and horizontal directions and coefficients of variation（COV） of Young＇s modulus on the surrounding soil deformation are investigated and discussed in detail. Results show that the effects of COV of Young＇s modulus on the deformation are more important than SOF. The effects of the anisotropy coefficient ξ on the maximum deformation are limited when ξ increases to 32. Additionally,the pattern of the surface subsidence curve depends highly on the distribution of the modulus above the tunnel. According to the results,the equivalent characteristic modulus is proposed for tunnel design in the typical weathered granite stratum in Xiamen.
作者
李健斌
陈健
罗红星
程红战
胡之锋
黄珏皓
张善凯
LI Jianbin;CHEN Jian;LUO Hongxing;CHENG Hongzhan;HU Zhifeng;HUANG Juehao;ZHANG Shankai(State Key Laboratory of Geomeehanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan,Hubei 430071,China;University of Chinese Academy of Sciences,Beijing 100049,China;Yunnan Dayong Expressway Project Construction Headquarters,Dali Bai Autonomous Prefecture,Yunnan 650200,Chinm 4.College of Civil Engineering,Hunan University,Changsha,Hunan410082,China)
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2018年第7期1748-1765,共18页
Chinese Journal of Rock Mechanics and Engineering
基金
中国科学院科技服务网络计划(STS)(KFJ-EW-STS–122)
国家重点基础研究发展计划(973)项目(2015CB057905)~~
关键词
隧道工程
双线盾构
随机场
地层变形
可靠度理论
等效特征模量
tunnelling engineering
twin shield ttmneling
random field
surrounding soil deformation
reliability theory
equivalent characteristic modulus
