围岩空间变异性对隧道稳定性影响及注浆加固优化  

Influence of Spatial Variability of Surrounding Rock on Tunnel Stability and Optimization of Grouting Reinforcement

作　　者：李东彪 曾志康 沈才华[3] 郭金勇 姜育科 LI Dongbiao;ZENG Zhikang;SHEN Caihua;GUO Jinyong;JIANG Yuke(China Communications Tunnel Bridge(Nanjing)Technology Co.,Ltd.,Nanjing,Jiangsu 211800,China;Research and Development Center of Tunnel Maintenance Technology of CCCC Infrastructure Maintenance Group Co.,Ltd.,Nanjing,Jiangsu 211800,China;College of Civil Engineering and Transportation,Hohai University,Nanjing,Jiangsu 210098,China)

机构地区：[1]中交隧桥(南京)技术有限公司,江苏南京211800 [2]中交基础设施养护集团有限公司隧道养护技术研发中心,江苏南京211800 [3]河海大学土木与交通学院,江苏南京210098

出　　处：《公路工程》2023年第6期14-22,共9页Highway Engineering

基　　金：国家自然科学基金重点项目(41830110);中交养护集团2020年重大科技研发项目(27100020Y251,27100020Y249)。

摘　　要：根据岩土体弹性模量呈现空间随机分布的特征,结合随机理论与Monte-Carlo方法,建立围岩单元环向统计分析法,把力学性质相近的单元归为一类,建立了能考虑四心圆公路隧道围岩空间变异性的隧道变形稳定性随机有限元法,揭示了围岩和注浆效果空间变异性特征对隧道变形稳定性的影响规律。结合皮家岭隧道研究显示:考虑0~3 m围岩深度范围内围岩弹性模量(平均值为0.5 GPa,标准差为15.0 GPa)的空间随机性时,可靠度0.90对应的洞壁最大位移的最大值为11.33 cm,比平均值10.63 cm大6.59%,相同空间变异性围岩位于3~6 m深度范围时,可靠度0.90对应的洞壁最大位移的最大值为10.85 cm,距离洞壁越近的围岩空间变异性对围岩位移安全的风险越大;考虑围岩空间变异性条件下注浆加固后围岩拱顶可靠度0.90最大位移值减小了约3.5%,极值的区间范围减少约25%。研究方法和结论为围岩空间变异性四心圆隧道的优化设计和施工安全控制提供了理论依据,更为探究围岩空间变异性的隧道可靠度设计提供思路。According to the characteristics of random spatial distribution of elastic modulus of rock and soil mass,combined with random theory and Monte-Carlo method,the circumferential statistical analysis method of surrounding rock elements is established,and the elements with similar mechanical properties are classified into one category.The random finite element method of tunnel deformation stability which can consider the spatial variability of surrounding rock of Sixinyuan highway tunnel is established,and the influence law of spatial variability of surrounding rock and grouting effect on tunnel deformation stability is revealed.According to the study of Pijialing Tunnel,when considering the spatial randomness of the elastic modulus of surrounding rock(average value is 0.5 GPa,standard deviation is 15.0 GPa)in the depth range of 0~3 m,the maximum displacement of the tunnel wall corresponding to the reliability of 0.90 is 11.33 cm,which is 6.59%larger than the average value of 10.63 cm.When the surrounding rock with the same spatial variability is in the depth range of 3~6 m,the maximum displacement of the tunnel wall corresponding to the reliability of 0.90.Considering the spatial variability of surrounding rock,after grouting reinforcement,the maximum displacement value of 0.90 reliability of surrounding rock vault decreases by about 3.5%,and the interval range of extreme value decreases by about 25%.The research and conclusion provide a theoretical basis for the optimal design and construction safety control of the four-center tunnel with spatial variability of surrounding rock,and provide ideas for the reliability design of the tunnel with spatial variability of surrounding rock.

关 键 词：围岩空间变异性 隧道洞壁位移 四心圆隧道 可靠度位移值 注浆加固 

分 类 号：U451.2[建筑科学—桥梁与隧道工程]