双参数层状地基中水平动荷载和扭转振动组合作用下受荷桩受力变形分析  

Analysis of deformation and force behavior of pile in double-parameter layered foundation subjected to combined horizontal dynamic load and torsional vibration

作　　者：江杰[1,2,3] 陈丽君 柴文成 艾永林[1,2] 欧孝夺 JIANG Jie;CHEN Li-jun;CHAI Wen-cheng;AI Yong-lin;OU Xiao-duo(School of Civil Engineering and Architecture,Guangxi University,Nanning,Guangxi 530004,China;State Key Laboratory of Featured Metal Materials and Life-Cycle Safety for Composite Structures,Guangxi University,Nanning,Guangxi 530004,China;Guangxi Ruiyu Construction Technology Co.,Ltd.,Nanning,Guangxi 530004,China)

机构地区：[1]广西大学土木建筑工程学院,广西南宁530004 [2]广西大学特色金属材料与组合结构全寿命安全国家重点实验室,广西南宁530004 [3]广西瑞宇建筑科技有限公司,广西南宁530004

出　　处：《岩土力学》2024年第4期961-972,共12页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.52068004)。

摘　　要：为了更准确地分析桩顶在承受水平动荷载H(t)和扭转振动T(t)组合荷载作用下的受力变形特性,基于Pasternak模型,考虑多向荷载间的相互作用,建立层状地基中H(t)-T(t)受荷桩简化分析模型。利用有限杆单元法推导出桩身内力位移数值解,并与已有相关理论解、模型试验和有限元模拟结果进行对比验证。参数分析表明:(1)与Winkler模型计算结果相比,考虑土体剪切效应后,桩顶水平位移和桩身最大弯矩分别减小了11.8%和10.5%。(2)增大外荷载无量纲频率可减小桩身水平位移和弯矩,但同时会减小H(t)-T(t)耦合刚度。(3)在层状地基中,表层土对桩身内力位移的影响最大,且存在临界影响深度,表层硬土的临界影响厚度是表层软土临界影响厚度的3.5~6.5倍。(4)采用杆单元模型可减少单元划分数量和计算时间,有效提高计算效率。In order to accurately analyze the internal force and deformation of pile under the combined horizontal dynamic load(H(t))and torsional vibration(T(t))on the top of the pile,a simplified analytical model of H(t)-T(t)loaded pile in layered foundation is established based on the Pasternak model,considering the interaction of multidirectional loads.The numerical solutions of the internal forces and displacements of the pile are derived by using the finite beam element method,and the results are compared with the existing theoretical solutions,model tests and finite element simulations.Parametric analysis shows that:(1)Compared with the calculation results of Winkler model,the horizontal displacement at the top of the pile and the maximum bending moment of the pile are reduced by 11.8%and 10.5%,respectively,after considering the shear effect of the soil.(2)Increasing the dimensionless frequency of the external load reduces the horizontal displacement and bending moment of the pile,and also reduces the H(t)-T(t)coupling stiffness.(3)In the layered foundation,the surface soil has the greatest influence on the internal force and displacement of the pile,and there is a critical influence depth of the surface soil.The critical influence thickness of the surface hard soil is 3.5–6.5 times that of the surface soft soil.(4)The beam element model reduces the number of element divisions and calculation time,which can effectively improve the calculation efficiency.

关 键 词：桩基 Pasternak模型 多向荷载 层状地基 有限杆单元法 

分 类 号：TU473[建筑科学—结构工程]