复杂地质条件下隧道锚承载特性多因素敏感性分析  

Multi-factor Sensitivity Analysis of Tunnel-type Anchorage Bearing Characteristics Under Complex Geological Conditions

作　　者：陈尚远 左成荣 张迎忠 Chen Shangyuan;Zuo Chengrong;Zhang Yingzhong(Power China Zhongnan Engineering Corporation Limited,Changsha 410014,China)

机构地区：[1]中国电建集团中南勘测设计研究院有限公司,湖南长沙410014

出　　处：《市政技术》2025年第3期163-170,共8页Journal of Municipal Technology

摘　　要：锚碇体是悬索桥的重要组成部分之一,是桥梁承载力的重要影响因素,其设计参数和围岩力学参数的选取都会对承载特性产生影响。因此,以赤水河大桥四川岸的隧道锚为背景,通过控制不同的地质参数(包括围岩黏聚力、内摩擦角和抗拉强度),以及隧道锚设计参数(包括隧道锚长度、主轴角和扩展角),进行了正交试验分析,得出29种试验工况。分析结果表明,隧道锚的破坏以拉剪破坏为主,其破坏形式是以后锚面为基础沿着锚塞体向地表逐渐扩展的锥形破坏;最终得出不同因素的敏感性关系从大到小依次为:隧道锚长度、围岩黏聚力、主轴角、扩展角、岩体抗拉强度、围岩内摩擦角。该研究结果为隧道锚的设计提供了理论依据,强调了在设计时应优先考虑围岩的黏聚力和锚碇长度,同时合理优化了设计参数,确保了桥梁的安全性和经济性。Anchorage is one of the essential components of suspension bridges and influencing factors of the bridge bearing capacity.Both the design parameters and the mechanical properties of the surrounding rock affect the bearing characteristics.Therefore,the tunnel-type anchorage of Chishui River Bridge by Sichuan side was taken as a case study.By controlling various geological parameters(cohesion,internal friction angle,and tensile strength of the surrounding rock),as well as tunnel anchor design parameters(anchor length,primary axis angle,and expansion angle),an orthogonal experimental analysis was conducted to get 29 test conditions.The results indicate that the failure of the tunnel anchor is primarily tensile-shear failure.On the base of the rear anchor face,a cone-shaped failure is extended along the anchor block toward the ground surface;Sensitivity analysis shows that the factors influencing bearing characteristics in descending order are as follows:tunnel anchor length,surrounding rock cohesion,primary axis angle,expansion angle,surrounding rock tensile strength,and internal friction angle of the surrounding rock.The research results provide a theoretical basis for the design of tunnel anchors.The cohesive strength of surrounding rock and anchor length should be priority considered in the design.At the same time,the design parameters are optimized to ensure the safety and cost-effectiveness of the bridges.

关 键 词：桥梁工程 隧道锚 承载特性 数值模拟 多因素敏感性分析 

分 类 号：U448.25[建筑科学—桥梁与隧道工程] U443.24[交通运输工程—道路与铁道工程]