在役PHC管桩复合路基滑塌事故的处治效果分析  

Analysis of Treatment Effect of PHC Pipe Pile Composite Subgrade Slide Accident in Service

作　　者：姚云龙 刘鑫[1,3] 洪宝宁[1,2] 孙东宁 邵志伟 YAO Yun-long;LIU Xin;HONG Bao-ning;SUN Dong-ning;SHAO Zhi-wei(Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering,Hohai University,Nanjing 210098,China;Tunnel and Underground Engineering Institute,Hohai University,Nanjing 210098,China;Geotechnical Engineering Institute,Hohai University,Nanjing 210098,China)

机构地区：[1]河海大学岩土力学与堤坝工程教育部重点实验室,南京市210098 [2]河海大学隧道与地下工程研究所,南京市210098 [3]河海大学岩土工程科学研究所,南京市210098

出　　处：《公路》2023年第8期12-21,共10页Highway

基　　金：国家自然科学基金青年基金资助项目,项目编号51609071。

摘　　要：针对PHC管桩复合路基深厚软基段在施工阶段出现的滑塌事故,结合广东某高速公路K31+100~K31+388路段软基加固实际工程,采用Plaxis 2D软件建立PHC管桩复合路基模型,研究了连系梁形式、桩长、桩间距、垫层参数、桩体垂直度、路堤填土加载方式对复合路基沉降和稳定性的影响。结果表明:原处理方案采用PHC管桩+桩帽形式,水平承载力低且抗干扰能力差,施工中的不利影响因素导致了滑塌事故的发生。不同结构形式的稳定性对比结果为:纵横向连系梁形式>横向连系梁形式>纵向连系梁形式>PHC管桩+桩帽形式>PHC管桩结构形式。将带纵横向连系梁形式桩应用于滑塌路段处治,通过对比实测数据与有限元分析结果表明,该形式能有效减小复合路基的沉降,实现了竖向控沉与侧向抗滑的效果。Aiming at the slide accident in the deep soft subgrade section of PHC pipe pile during the construction stage,combined with the actual soft subgrade reinforcement project of K31+100~K31+388 section of a highway in Guangdong,the Plaxis 2D software is used to establish the PHC pipe pile composite subgrade model.The influences of connecting beam form,pile length,pile spacing,cushion parameters,pile perpendicularity and embankment filling loading mode on settlement and stability of composite subgrade are studied.The results show that the original treatment scheme adopts the form of PHC pipe pile + pile cap,which has low horizontal bearing capacity and poor anti-interference ability,and the adverse factors in construction lead to the occurrence of the slide accident.Comparisons on the stability of different structural forms shows longitudinal and transverse tie beam form transverse connected beam form longitudinal connected beam formPHC pipe pile + pile cap formPHC pipe pile structure form.By comparing the measured data with the finite element analysis,it is shown that this form can effectively reduce the settlement of the composite subgrade,and realize the effect of vertical control of settlement and lateral resistance to slip.

关 键 词：PHC管桩 复合路基 路基滑塌 纵横向连系梁 有限元分析 

分 类 号：U416.1[交通运输工程—道路与铁道工程] P642.22[天文地球—工程地质学]