摘要
由于饱和土中土体颗粒与孔隙水的相互作用以及桩与土体的不同渗透率,饱和土体中桩基的力学行为与单相土中桩基力学行为有很大的差别。基于饱和多孔介质理论,考虑桩纵向振动时的横向变形及惯性效应,将桩等效为Rayleigh-Love杆,在频率域中研究了饱和黏弹性土层中端承桩纵向振动的动力特性,给出了饱和黏弹性土层和桩纵向振动时动力响应的解析解及桩头复刚度的解析表达式。通过数值计算,给出了桩头动刚度因子和阻尼随激励频率的响应,考察了饱和土物性参数、桩土模量比、桩长径比、泊松比等参数对桩头刚度因子和阻尼的影响。研究表明,对于大直径桩,当外载荷激励频率较大时桩横向效应对桩头刚度因子和阻尼有显著的影响。
Because of interaction between solid granulae and pore water as well as different permeabilities of pile and saturated soil,the mechanical behavior of a pile in a saturated soil is greatly distinct from that of the pile in single phase soil.Based on the theory of saturated porous media,taking effect of the transversal deformation and inertia of the pile into account and modeling pile as a Rayleigh-Love rod,the dynamical behavior of vertical vibration of the pile in a saturated viscoelastic soil layer is investigated in frequency domain;and the analytical solutions for vertical vibrations of the pile and saturated viscoelastic soil layer are obtained;and an analytical expression of the dynamical complex stiffness of the pile top is presented.The responses of dynamic stiffness factor and damping of pile top against the frequency are shown in figures with the numerical method;and the influences of the soil parameters,modulus ratio of the pile to soil,ratio of the length to radius of the pile and Poisson ratio on the stiffness factor and damping are analyzed.It is shown that the influence of transversal effects on the stiffness factor and damping is much great for the pile with large diameter when the exciting frequency is large.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2011年第6期1857-1863,共7页
Rock and Soil Mechanics
基金
国家自然科学基金资助(No.10872124)
关键词
饱和多孔介质
桩-土相互作用
横向效应
纵向振动
saturated porous medium
pile-soil interaction
transversal effect
vertical vibration
