限阻器在高水平地应力隧道支护中的研究与应用

为解决蒙华铁路如意隧道高水平地应力岩层段初期支护因受力过大而破坏的问题,文章通过理论分析、数值模拟以及现场施工反馈等方法,并基于室内试验、地应力测试以及现场监控量测数据,对限阻耗能支护技术的工程应用方法及作用机理进行研究,结果表明:(1)针对高构造应力环境,在保证围岩自承能力不明显降低,且不明显增加松散压力的前提下,可控制地引导围岩变形、围岩能量释放分散转移的限阻高延性支护是合理可行的;(2)限阻器是一种合理有效的限阻高延性支护手段,成功解决了如意隧道高地应力水平岩层中初期支护破坏问题;(3)限阻器显著降低了结构内力,但也改变了结构的内力分布,在应用中还需进一步完善。

Research and Application of Support Resistant Limiting Dampers in the Tunnel with High Horizontal Geostress

In order to deal with the failures of primary lining of Ruyi tunnel on Menghua railway with high geo⁃stress,through theoretical analysis,numerical simulation and on-site construction feedback methods,the engineer⁃ing application method and action mechanism of the support technique with resistance limiting and energy dissipa⁃tion are studied based on laboratory test,geostress testing and field monitoring data.The results show that:(1)under the condition of high tectonic stress,the tunnel support with high ductility and resistance limiting is feasible since it can controllably guide the deformation,energy release and transfer of surrounding rocks under the premise that the bearing capacity of surrounding rock is not obviously reduced and the loosening pressure is not obviously increased;(2)the support resistant limiting damper(SRLD)is a reasonable and effective supporting means with high ductility and it successfully solves the problem of primary support failure in Ruyi tunnel with high geostress;(3)the SRLD significantly reduces structural internal force but also changes its distribution,thus further improvement is needed in practical application.