Ⅴ级围岩全断面扩挖隧道的二次衬砌支护时机  

Reasonable supporting time of secondary lining of full section expanded tunnel in grade Ⅴ surrounding rock

作　　者：杨俊[1] 秦艺源 谢支钢 丁雪菲 梁勇 YANG Jun;QIN Yiyuan;XIE Zhigang;DING Xuefei;LIANG Yong(Collaborative Innovation Center of Geological Hazards and Ecological Environment in Three Gorges Area in Hubei Province,China Three Gorges University,Yichang,Hubei 443002,China;Yiling District Highway Administration Bureau of Yichang City,Yichang,Hubei 443100,China)

机构地区：[1]三峡大学三峡地区地质灾害与生态环境湖北省协同创新中心,湖北宜昌443002 [2]宜昌市夷陵区公路建设养护中心,湖北宜昌443100

出　　处：《江苏大学学报(自然科学版)》2025年第2期205-211,共7页Journal of Jiangsu University:Natural Science Edition

基　　金：国家自然科学基金资助项目(41402259)。

摘　　要：为了研究既有Ⅴ级围岩隧道扩挖的二次衬砌支护时机,利用Midas GTS有限元数值模拟方法,建立有限元数值模拟模型,引入荷载释放率和位移释放率的概念,结合木鱼槽隧道扩挖工程实例,将数值模拟数据与监控实测数据进行对比分析.研究结果表明:相较新建隧道,既有隧道扩挖过程中变形量较小,且变化速率较慢;随着掌子面的不断向前推进,荷载释放率和位移释放率均不断增大,并最终达到稳定;随着二次衬砌荷载承担比例的增大,拱顶沉降和水平位移均有一定程度的减小,证明在隧道扩挖过程中,二次衬砌的提前施作有利于控制围岩变形;衬砌施作完成后变形仍会继续发生,需要后续的监控数据及时进行反馈,以保证隧道安全,同时还可以得到既有公路隧道扩挖过程中的以荷载释放率和位移释放率为控制指标的二次衬砌合理支护时机.To investigate the secondary lining support timing for expanding the existing tunnel in grade V surrounding rock,the finite element numerical simulation method of Midas GTS was used to establish finite element numerical simulation model,and the concepts of load release rate and displacement release rate were introduced.Combining the example of the Muyucao tunnel expansion project,the numerical simulation data was compared with the monitoring measured data.The results show that compared with new tunnel construction,the deformation volume in the expansion process of existing tunnel is smaller,and the rate of change is slower.As the cutting face is continuously advanced,the load release rate and displacement release rate are both increased continuously and eventually stabilized.As the proportion of secondary lining load is increased,the crown subsidence and horizontal displacement are both decreased to some extent,which illuminates that the early construction of secondary lining in the tunnel expansion process is beneficial for controlling rock mass deformation.The deformation will continue to occur even after the lining is constructed,and the subsequent monitoring data should be fed back in time to ensure tunnel safety.The reasonable support timing for the secondary lining in the expansion process of existing highway tunnel with load release rate and displacement release rate as control indicators is obtained.

关 键 词：隧道 全断面扩挖 二次衬砌施作时机 围岩变形 数值模拟 

分 类 号：TU528.1[建筑科学—建筑技术科学]