悬索桥岩锚式锚碇的承载特性研究  

Bearing Behavior Research of Rock Anchorage System for Suspension Bridge

作　　者：郑晓卿 李伯 陈鹏 魏益峰 张雨帆 ZHENG Xiaoqing;LI Bo;CHEN Peng;WEI Yifeng;ZHANG Yufan(Zhejiang Institute of Communications Co.,Ltd.,Hangzhou 310030;Linhai City Industrial Development Group Co.,Ltd.,Linhai Zhejiang 317000)

机构地区：[1]浙江数智交院科技股份有限公司,杭州310030 [2]临海市城市产业发展集团有限公司,浙江临海317000

出　　处：《公路交通技术》2024年第1期87-94,共8页Technology of Highway and Transport

摘　　要：悬索桥岩锚锚碇系统能充分利用岩体承载能力,为了研究其承载特性和破坏模式,以主跨为1768 m的某公路双塔单跨吊钢箱梁悬索桥岩锚锚碇为例,先建立了锚址区地质概化模型,通过原位测试和室内试验分析得到岩体力学特性;后采用FLAC^(3D)建立了锚碇系统及围岩相互作用的三维模型,模拟分析了岩锚区围岩塑性区分布规律、变形特征、岩锚破坏模式;再采用楔形断裂法得到了岩锚的抗拔安全系数。结果表明:1)岩锚锚碇系统的破坏机理为主缆拉力作用下,锚体及周边围岩沿着破裂角发生整体拉剪复合破坏;2)通过超载法得到该桥岩锚锚碇围岩稳定安全系数为7.0;3)采用“楔形断裂法”得到岩锚锚碇的抗拔安全系数为4.0。The rock anchorage system of suspension bridge can make full use of the bearing capacity of rock mass.In order to study the load-bearing characteristics and failure mode,we first established a geological conceptual model,and obtained the mechanical properties of rock mass,based on the rock anchorage system of a highway double-tower single-span steel box girder suspension bridge with a main span of 1768 m.Then,FLAC^(3D) was used to establish a three-dimensional model of the interaction between the anchorage system and the surrounding rock,and the distribution of the plastic zone,deformation characteristics,and failure mode of the rock anchorage in the rock anchor area were simulated and analyzed.Finally,the uplift stability coefficient is obtained by using the wedge fracture method.The The results show that:1)The failure mode of the rock anchorage system is that the rock anchorage and surrounding rocks undergo overall tensile-shear composite failure along the fracture angle under the tension of the main cable;2)Through the overload method,the stability safety coefficient of the surrounding rock of the rock anchorage system is 7.0;3)Using the wedge fracture method,the uplift stability coefficient of the rock anchorage is 4.0.

关 键 词：悬索桥 岩锚锚碇 承载特性 围岩稳定安全系数 抗拔安全系数 

分 类 号：U443.24[建筑科学—桥梁与隧道工程]