基于组合赋权的白云岩隧洞超前支护综合评价  

Comprehensive Evaluation of Overrun Support Optimization for Sanded Dolomite Tunnels Based on Combinatorial Assignment

作　　者：陈光友 王占宇 陈健 晏启祥[1] 龚凡 代崇锐 何复生 CHEN Guang-you;WANG Zhan-yu;CHEN Jian;YAN Qi-xiang;GONG Fan;DAI Chong-rui;HE Fu-sheng(Key Laboratory of Traffic Tunnel Engineering of the Ministry of Education,Southwest Jiaotong University,Chengdu 610031,Sichuan Province,China;China Railway Development and Investment Group Limited,Kunming 650200,Yunnan Province,China;China Railway Second Bureau First Engineering Company Limited,Guiyang 550007,Guizhou Province,China)

机构地区：[1]西南交通大学交通隧道工程教育部重点实验室,四川成都610031 [2]中铁开发投资集团有限公司,云南昆明650200 [3]中铁二局第一工程有限公司,贵州贵阳550007

出　　处：《中国农村水利水电》2024年第11期233-239,246,共8页China Rural Water and Hydropower

基　　金：中国中铁科技研究开发计划课题(2020-重大专项-04)。

摘　　要：为解决滇中引水工程剧烈砂化白云岩隧洞超前小导管支护效果不佳、超挖超耗严重等问题,通过数值模拟计算了以超前小导管长度、环向间距、循环进尺为因素设计的正交工况。根据数值模拟计算结果,基于主客观组合赋权对围岩变形、结构受力和施工成本等指标进行了综合评价。研究结果表明:增大超前小导管长度和减小循环进尺分别可以有效控制拱顶沉降和隧洞侧壁收敛,结构受力受循环进尺影响程度最大,小导管长度和循环进尺对施工成本的影响稍大。结合综合评价以及现场试验结果,在依托工程的剧烈砂化白云岩地层条件下,超前小导管支护参数宜为长度3 m、环向间距0.2 m、钢架间距0.6 m、循环进尺1.8 m,经监测该参数组合下围岩稳定性良好,掉块现象减少,超挖控制效果增强。Numerical simulations were carried out to solve the problems of poor advanced small conduit support and serious over-excavation and over-consumption in the drastically sandy dolomite tunnel of the Dianzhong water diversion project.The orthogonal working conditions designed with the length of advanced small conduit,annular spacing,and cyclical footage as factors were calculated.According to the numerical simulation results,a comprehensive evaluation of the indicators of surrounding rock deformation,structural stress and construction cost was carried out based on the subjective and objective combination assignment.The results show that increasing the length of advanced small conduit and reducing the cyclical footage can effectively control the settlement of the vault and the convergence of the tunnel sidewalls,respectively;the structural force is affected by the cyclical footage to the greatest extent,and the length of small conduit and cyclical footage have a slightly greater impact on the construction cost.Combined with the comprehensive evaluation and field test results,under the condition of strongly sandy dolomite stratum of the relying project,the parameters of advanced small conduit support should be 3 m in length,0.2 m in annular spacing,0.6 m in steel frame spacing,and 1.8 m in cyclical footage,and the surrounding rock stability is good under the monitoring of this parameter combination,and the phenomenon of dropping blocks is reduced,and the effect of over-excavation control is enhanced.

关 键 词：数值模拟 组合赋权 正交试验 超前小导管 砂化白云岩 

分 类 号：TV672.1[水利工程—水利水电工程]