滑坡体内框架桩设计计算方法及工程应用研究  

Study on Design Calculation Method and Engineering Application of Frame Piles inside Landslide Body

作　　者：胡会星[1] 李宁[1] 任华锋[1] HU Huixing;LI Ning;REN Huafeng(China Railway Eryuan Engineering Group Co.,Ltd.,Chengdu 610031,China)

机构地区：[1]中铁二院工程集团有限责任公司,成都610031

出　　处：《路基工程》2023年第4期113-118,共6页Subgrade Engineering

基　　金：中铁二院工程集团有限责任公司科研项目:山区铁路滑坡体内框架式双排抗滑桩结构受力性能研究(KYY2015007(15-18))。

摘　　要：框架桩作为一种新型的重型支挡结构,由前桩、后桩、横梁和次梁四个部分组成,具有抗力大、变形小和经济性好等特点,可用于加固巨型滑坡等工点。本文将框架桩分解为前桩悬臂段、中部框架区段和桩基锚固段三个静定结构进行受力分析,依据微元受力建立平衡方程,结合边界条件推导了结构的内力理论计算公式,并与数值模拟、现场测试结果进行对比。结果表明:理论计算结果比数值模拟结果平均偏大20%,比现场测试结果平均偏大30%,理论计算结果偏于安全。框架桩其前桩弯矩沿竖向呈“W”型分布,后桩弯矩沿竖向呈“Z”型分布,横梁弯矩沿横向呈“半抛物线”型分布,结构最大弯矩分别位于前桩锚固点附近、桩梁节点附近,在设计过程中应加强节点设计。Frame pile,as a new type of heavy retaining structure,is composed of front pile,rear pile,crossbeam and secondary beam.It has the characteristics of high resistance,small deformation and low cost,and can be used as reinforcement at giant landslide and other working points.Herein the frame pile was discomposed into three statically determinate structures for stress analysis,including cantilever section of front pile,middle frame section,and anchorage section of pile foundation and;according to the force of infinitesimal element,the equilibrium equation was established,and with boundary condition,the theoretical formula calculating internal force of the structure was derived and then compared with the results of numerical simulation and field test.The result shows that,the result of theoretical calculation is on the average 20%larger than the result of numerical simulation,and on the average 30%larger than the result of field test,thus the result of theoretical calculation is conservative.The bending moment of the front frame pile is distributed in a"W"shape along vertical direction,the bending moment of the rear pile in a"Z"shape along vertical direction,and the bending moment of the beam in a"semi parabolic"shape along transverse direction.The maximum bending moment of the structure is respectively located near the anchoring point of the front pile and the pile beam joint.Therefore,the joint design should be strengthened during the design process.

关 键 词：滑坡 框架桩 设计计算方法 结构内力 弯矩 

分 类 号：U213.14[交通运输工程—道路与铁道工程]