限阻耗能型支护在大变形双线铁路隧道中的应用  

Application of support resistant limiting damper in large-section double-track railway tunnel

作　　者：戴军 杨鑫 王建军 仇文革[2,3] 朱麒 DAI Jun;YANG Xing;WANG Jianjun;QIU Wenge;ZHU Qi(China Sinohydro Bureau 3 Co.,Ltd.,Xi′an 710024,Shaanxi,China;Key Laboratory of Traffic Tunnel Engineering of Ministry of Education,Southwest Jiaotong University,Chengdu 610031,Sichuan,China;Chengdu Tianyou Tunnel Key Technology Co.,Ltd.,Chengdu 610031,Sichuan,China)

机构地区：[1]中国水利水电第三工程局有限公司,陕西西安710024 [2]西南交通大学交通隧道工程教育部重点试验室,四川成都610031 [3]成都天佑智隧科技有限公司,四川成都610031

出　　处：《隧道与地下工程灾害防治》2022年第4期44-51,共8页Hazard Control in Tunnelling and Underground Engineering

基　　金：国家自然科学基金重大资助项目(71942006);国家自然科学基金面上资助项目(51678497);老中铁路复杂地质条件下隧道工程施工关键技术研究(2018-05)。

摘　　要：为解决中老铁路沙嫩山二号隧道双线段大变形问题,引入限阻耗能型支护设计原理,从合理利用围岩峰后承载能力的角度出发,设计符合现场工况的限阻耗能型支护方案。结合试验段的初支工作状态、结构变形及内力监测结果进行综合分析,验证采用限阻耗能支护结构治理炭质板岩地层隧道大变形的合理性。结果表明:隧道开挖后,系统能量主要通过围岩塑性应变能耗散,支护耗散的能量是有限的,若能充分利用围岩的塑性变形能力,通过围岩自身耗散能量,有利于完成能量的守恒与转换,从而降低围岩压力;限阻耗能型支护属于受压屈服型控制体系,适用于受形变压力控制的小偏心受压环境,在降低后的围岩压力下辅助围岩在弹塑性状态下耗散能量而不破坏;限阻耗能型支护在沙嫩山二号隧道双线段得到成功应用,相比“强支硬顶”,大幅度降低了围岩压力,在不加强初支参数的情况下避免了初支开裂、钢架屈曲等问题,在保证安全的前提下提高了工程的经济性。In order to solve the large deformation problem of Shanenshan No.2 Tunnel of the China-Lao′s Railway,the design principle of the support resistant limiting damper(SRLD)was introduced,and the energy-consuming support scheme with the SRLD was designed according to the field working conditions from the point of rational utilization of the load-bearing capacity behind the peak of the surrounding rock.Based on the comprehensive analysis of the working state,structural deformation and internal force monitoring results of the primary support of the test section,the rationality of using the SRLD to treat the tunnel with carbonaceous SLATE stratum was verified.The results showed that after tunnel excavation,the system energy was dissipated mainly through the plastic strain energy of surrounding rock,while the energy dissipated by support was limited.Therefore,if the plastic deformation ability of surrounding rock could be fully utilized and the energy could be dissipated by surrounding rock itself,the energy conservation and conversion could be accomplished,thus reducing the pressure of surrounding rock.The SRLD was a pressure yielding control system,suitable for small eccentric pressure environments controlled by deformation pressure,which assised the surrounding rock to dissipate energy in an elastic-plastic state under reduced surrounding rock pressure,without damage.The SRLD was successfully applied in the double-lane section of Shannon Hill Tunnel No.2,which significantly reduced the pressure on the surrounding rock compared to the“strong support and hard roof”,and avoided problems such as cracking of the initial support and buckling of the steel frame without strengthening the initial support parameters,thus improving the economy of the project while ensuring safety.

关 键 词：大变形隧道 形变压力 小偏心受压 限阻耗能型支护 能量释放 

分 类 号：U25[交通运输工程—道路与铁道工程]