基于状态空间法的阶梯型变截面水平受荷桩分析方法  

Analytical solutions for laterally loaded step-tapered piles by state space method

作　　者：张晓笛 王金昌[1,2] 杨仲轩[1,3] 龚晓南 徐荣桥[1,3] ZHANG Xiaodi;WANG Jinchang;YANG Zhongxuan;GONG Xiaonan;XU Rongqiao(College of Civil Engineering,Zhejiang University,Hangzhou 310058,China;Center for Balance Architecture,Zhejiang University,Hangzhou 310058,China;Zhejiang Provincial Engineering Research Center for Digital&Smart Maintenance of Highway,Hangzhou 310051,China)

机构地区：[1]浙江大学建筑工程学院,浙江杭州310058 [2]浙江大学平衡建筑研究中心,浙江杭州310058 [3]公路数智养护浙江省工程研究中心,浙江杭州310051

出　　处：《岩土工程学报》2023年第9期1944-1952,共9页Chinese Journal of Geotechnical Engineering

基　　金：浙江省“尖兵”“领雁”研发攻关计划项目(2022C03180);浙江省交通运输厅项目(ZJXL-JTT-202201A,202303);国家自然科学基金项目(52078457);浙江大学浙江交工协同创新联合研究中心研发项目(2021001)。

摘　　要：为研究阶梯型变截面桩的水平承载特性,基于Timoshenko梁理论,建立了综合考虑桩基尺寸效应、剪切变形和桩基材料非线性效应的四弹簧模型及其状态方程,获得了非线性桩土相互作用下任意长细比的桩截面内力与变形解析解。通过与已有文献中现场试验结果对比分析,验证该方法的适用性和有效性,并讨论了变径位置、桩径比和弹性模量比对桩基受荷特性的影响。研究结果表明:(1)桩基水平承载力对三者的敏感性为:桩径比>变径位置>弹性模量比;(2)综合考虑桩承载能力和经济性,建议变径位置、桩径比和弹性模量比取0.6。To analyze the response of laterally loaded step-tapered piles,a four-spring model is proposed based on the Timoshenko beam theory considering the effects of pile diameter,shear deformation and nonlinear pile material behavior.The analytical solutions for the internal forces and deformations with arbitrary slenderness ratio can be derived by the state space method considering the nonlinear pile–soil interaction.The solutions are validated through the available field test results in the literatures.Furthermore,the influences of pile parameters,such as the variation position of the diameter,diameter ratio and Young’s modulus ratio,on the pile loading responses are proposed.The results show that:(1)The sensitivity of these parameters follows the descending order:pile diameter ratio>variation position of pile diameter>Young’s modulus ratio.(2)After trade-off between the pile lateral bearing capacity and the cost,it is suggested that the optimal variation position of the diameter,the pile diameter ratio and Young’s modulus ratio should be set as 0.6.

关 键 词：阶梯型变截面桩 水平受荷 桩土相互作用 TIMOSHENKO梁 四弹簧模型 状态空间法 

分 类 号：TU473.1[建筑科学—结构工程]