摘要
为研究高应力软岩蠕变特性对隧道围岩变形预测的影响,以木寨岭公路隧道为依托,首先采用三维计算模型与多元线性回归相结合的方法分析初始地应力场,并结合围岩段落划分,选择典型计算断面;其次,提出基于[BQ]值的围岩参数取值方法,确定典型计算断面的围岩参数;而后,开展基于M-C模型和Cvsic模型的断面变形计算,剖析岩体蠕变特性对围岩变形的影响;最终,对比了预测结果与实际围岩变形。结果表明:(1)岩体蠕变特性对围岩变形具有明显增大效应,围岩位移增长量与横断面平均主应力呈正相关;(2)围岩条件越差,蠕变增大效应越显著;横断面平均主应力越大,蠕变增大效应中位移增长量越大,而位移增长率变化不明显;(3)蠕变特性对围岩变形等级预测有明显影响,M-C模型预测结果弱于Cvisc模型,与实际围岩变形情况存在较大差异。研究结果为在高应力软岩隧道变形预测中引入岩体蠕变效应奠定了实践基础。
To study the influences of high-stress soft rock creep characteristics on deformation prediction of surrounding rock of tunnels, the Muzhailing highway tunnel is taken as the support project. Firstly, the initial ground stress field is analyzed using a three-dimensional simulation model combined with multiple linear regression. The typical calculation sections are selected in conjunction with the section division of the surrounding rock. Secondly, the relevant method based on the [BQ] value is proposed to determine the parameters of the surrounding rock in the typical calculation section. Then, the section deformation is calculated based on the M-C model and the Cvsic model to analyze the influences of the creep characteristics of rock on the deformation of the surrounding rock. Finally, the predicted results are compared with the actual ones. The results show that:(1)The creep characteristics of rock mass have significant increase effects on the deformation, and the displacement growth rate is positively correlated with the average principal stress of cross-section.(2) The worse the surrounding rock condition, the more pronounced the creeping increase effects. The greater the average principal stress of the cross-section, the larger the displacement growth rate in the creep increase effects, while the change in the displacement growth rate is less noticeable.(3)The creep characteristics have significant effects on the prediction of the deformation level of the surrounding rock. The predicted results by the M-C model are weaker than those by the Cvisc model, which are pretty different from the actual deformations of the surrounding rock. The results lay a practical foundation for introducing the creep effects into the deformation prediction of high-stress soft rock tunnels.
作者
郭新新
汪波
王振宇
于家武
GUO Xinxin;WANG Bo;WANG Zhenyu;YU Jiawu(College of Environment and Civil Engineering,Chengdu University of Technology,Chengdu 610059,China;Key Laboratory of Transportation Tunnel Engineering,Ministry of Education,Southwest Jiaotong University,Chengdu 610031,China;The 2nd Engineering Co.,Ltd.of China Railway Tunnel Group,Sanhe 065201,China)
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2023年第3期652-660,共9页
Chinese Journal of Geotechnical Engineering
基金
国家自然科学基金项目(U2034205)
甘肃省科技计划项目(19ZD2GA005)
中铁隧道集团二处有限公司科技研发计划项目(2020-05)。
关键词
高应力软岩隧道
变形预测
蠕变效应
数值模拟
工程检验
high-stress soft rock tunnel
deformation prediction
creep effect
numerical simulation
engineering inspection
