摘要
为了探究竖向P波作用下摩擦桩在饱和冻土地基中的竖向振动响应,基于波在饱和冻土中的传播理论,考虑土骨架、冰和水的相互作用,建立竖向P波摩擦桩在饱和冻土中传播的理论模型.采用Helmholtz分解方法和分离变量法,结合边界条件和P波的传播特性,给出竖向P波作用下饱和冻土的解析解.考虑摩擦桩与饱和冻土耦合作用,得到桩在饱和冻土中振动的解析解,进而给出摩擦桩的运动响应因子、摩擦桩的运动放大因子以及饱和冻土对桩的阻抗.通过数值算例,验证了计算模型的正确性;并通过参数分析,研究了孔隙率、桩长细比、桩-土模量比、泊松比、土体饱和度、土体阻尼和温度对桩身竖向抗震特性的影响规律.研究发现,桩-土模量比、桩长细比、土体饱和度、土体阻尼和温度对摩擦桩在饱和冻土中的振动有显著影响,桩的泊松比以及饱和冻土的孔隙率对桩的运动响应影响不大.研究结果为实际工程中摩擦桩在饱和冻土中的抗震设计提供了理论基础,对优化抗震参数、提升冻土-桩相互作用的预测精度等提供关键依据.
In order to explore the vertical vibration response of friction piles in saturated frozen soil foundations under the action of vertical P-waves,based on the theory of wave propagation in saturated frozen soil and considering the interaction among soil skeletons,ice and water,a theoretical model for the propagation of friction piles in saturated frozen soil under the action of vertical P-waves is established.By using the Helmholtz decomposition method and the separation variable method,combined with the boundary conditions and the propagation characteristics of P-waves,the analytical solution of saturated permafrost under the action of vertical P-waves is given.Considering the coupling effect between the friction pile and saturated frozen soil,the analytical solution of the pile’s vibration in saturated frozen soil is obtained.Then,the motion response factor of the friction pile,the motion amplification factor of the friction pile,and the impedance of saturated frozen soil to the pile are given.The correctness of the calculation model was verified through numerical examples.Through parameter analysis,the influence laws of porosity,pile slenderness ratio,pile-soil modulus ratio,Poisson’s ratio,soil saturation,soil damping and temperature on the vertical seismic characteristics of the pile body were studied.The research finds that the pile-soil modulus ratio,pile-slenderness ratio,soil saturation,soil damping and temperature have significant effects on the vibration of friction piles in saturated frozen soil,while the Poisson’s ratio of the pile and the porosity ratio of saturated frozen soil have little influence on the motion response of the pile.The research results obtained in this study provide a solid theoretical basis for the seismic design of friction piles in saturated frozen soil under actual engineering scenarios,and also offer a key basis for further optimizing seismic parameters and effectively improving the prediction accuracy of the interaction mechanism between frozen soil and piles.
作者
曹小林
曾乐平
周凤玺
戴国亮
Cao Xiaolin;Zeng Leping;Zhou Fengxi;Dai Guoliang(School of Civil Engineering,Lanzhou University of Technology,Lanzhou 730050,China;Engineering Research Center of Disaster Mitigation in Civil Engineering of Ministry of Education,Lanzhou University of Technology,Lanzhou 730050,China;School of Civil Engineering,Southeast University,Nanjing 211189,China)
出处
《力学学报》
北大核心
2025年第10期2374-2387,共14页
Chinese Journal of Theoretical and Applied Mechanics
基金
国家自然科学基金(52408368,51978320)
2024年高校教师创新基金(2024A-019)
兰州理工大学红柳优秀青年人才支撑计划,甘肃省重点研发计划(25YFGE002)
天水市科技支撑计划(TS-STK-2024A-283)资助.
关键词
地震P波
饱和冻土
运动响应
竖向振动
理论分析
seismic P wave
saturated frozen soil
motor response
vertical vibration
theoretical analysis
