Vertical dynamic impedance of end‐bearing pile groups embedded in homogeneous unsaturated soils

Ma, Wenjie; Shan, Yao; Ke, Xiang; Wang, Binglong; Zhou, Shunhua

doi:10.1002/nag.3340

Cited by 27 publications

(6 citation statements)

References 66 publications

(136 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Genuchten 35 presented an empirical formula form for SWCC models based on many numerous experiments. In recent years, the Van–Genuchten model was used extensively by many researchers to describe the dynamic response of the unsaturated soil 36–41 . Considering that the complex properties of the three‐phase soil medium under Rayleigh waves, some basic assumptions must be added to simplify coupled partial differential equations for elastic wave propagation: The solid skeleton is treated as a statistically homogeneous and isotropic medium. The air will not dissolve into the fluid, and the interface between fluid and air phase is so clear to separate each phase.…”

Section: Free Field Response Of Unsaturated Soil Subjected To Rayleig...mentioning

confidence: 99%

“…In recent years, the Van-Genuchten model was used extensively by many researchers to describe the dynamic response of the unsaturated soil. [36][37][38][39][40][41] Considering that the complex properties of the three-phase soil medium under Rayleigh waves, some basic assumptions must be added to simplify coupled partial differential equations for elastic wave propagation:…”

Section: Wave Equations and Boundary Conditionsmentioning

confidence: 99%

See 1 more Smart Citation

Flexible support of a pile embedded in unsaturated soil under Rayleigh waves

Yang

Líu

et al. 2022

Earthq Engng Struct Dyn

View full text Add to dashboard Cite

Under the action of Rayleigh waves, pile head is easy to rotate with a concrete pile cap, and pure fixed-head condition is rarely achieved, which is a common phenomenon for it usually occurs on the precast piles with insufficient anchorage. In addition, the propagation characteristics of Rayleigh wave have been changed significantly due to the existence of capillary pressure and the coupling between phases in unsaturated soil, which significantly affects the pile-soil interaction. In order to study the above problems, a coupled vibration model of unsaturated soil-pile system subjected to Rayleigh waves is established on the basis that the pile cap is equivalent to a rigid mass block. Meanwhile, the soil constitution is simplified to linear-elastic and small deformations are assumed to occur during the vibration phase of soil-pile system. Then, the horizontal dynamic response of a homogeneous free-field unsaturated soil caused by propagating Rayleigh waves is obtained by using operator decomposition theory and variable separation method. The dynamic equilibrium equation of a pile is established by using the dynamic Winkler model and the Timoshenko beam theory, and the analytical solutions of the horizontal displacement, rotation angle, bending moment and shear force of pile body are derived according to the boundary conditions of flexible constraint of pile top. Based on the present solutions, the rationality of the proposed model is verified by comparing with the previous research results. Through parametric study, the influence of rotational stiffness and yield bending moment of pile top on the horizontal dynamic characteristics of Rayleigh waves induced pile is investigated in detailed. The analysis results can be utilized for the seismic design of pile foundation under Rayleigh waves.

show abstract

Section: Free Field Response Of Unsaturated Soil Subjected To Rayleig...mentioning

confidence: 99%

Section: Wave Equations and Boundary Conditionsmentioning

confidence: 99%

Flexible support of a pile embedded in unsaturated soil under Rayleigh waves

Yang

Líu

et al. 2022

Earthq Engng Struct Dyn

View full text Add to dashboard Cite

show abstract

“…Wang and Ai [15] studied the vertical vibration of pile groups with rigid caps in multilayer porous-saturated soil based on the finite element method, and the pile is regarded as a one-dimensional rod. Ma et al [16] considered the soil as a three-dimensional axisymmetric continuum, considered the effects of radial and vertical displacement and saturation on the dynamic shear modulus of soil, and studied the vertical dynamic impedance of end-bearing pile groups in homogeneous unsaturated soil. Finite element method and boundary element method need special analysis programs, and the amount of calculation is huge, so they are difficult to be applied to large-scale problems.…”

Section: Introductionmentioning

confidence: 99%

Study on the Lateral Dynamic Impedance of Pile Groups in Transversely Isotropic Soil Using Novak’s Plane Model

Lin-chao

Qi-fang

2023

Journal of Applied Mathematics

View full text Add to dashboard Cite

In order to consider the effect of anisotropy of soil around the pile on the lateral vibration of pile groups, the soil around the pile is regarded as a transversely isotropic medium, and a lateral dynamic interaction model of pile-pile in transversely isotropic soil is established. According to Novak’s plane assumption and wave propagation theory, the lateral vibration of transversely isotropic soil layer is solved by introducing potential function and using mathematical and physical means, and the attenuation function of lateral displacement of free field is given. The Dobry and Dazetas simplified solution of attenuation function is different from that of solution of plane model. The pile-pile horizontal dynamic interaction factor in transversely isotropic soil is obtained by using the initial parameter method and Krylov function. The horizontal dynamic impedance of pile groups is obtained by using the pile-pile superposition principle. The change rule of the lateral displacement attenuation function of transversely isotropic soil with frequency is related to the direction and frequency. The ratio G h v of the shear modulus in the lateral plane to the shear modulus in the vertical plane and the pile spacing S / d have a great impact on the lateral vibration of pile groups, and when the pile spacing is large, the curves of attenuation function varying with frequency fluctuate greatly. The ratio of elastic modulus of pile to vertical plane shear modulus of soil E p / G v has an effect on the lateral stiffness of pile groups, which is related to frequency, while the effect on dynamic damping is not affected by frequency. The difference of mechanical properties on different surfaces of soil around the pile has a great influence on the lateral vibration of pile groups in transversely isotropic soil, and the influence of the anisotropy on the attenuation function of the lateral displacement and the dynamic impedance cannot be ignored.

show abstract

“…Based on a Biot-type model, Ye and Ai 64,65 investigated the axisymmetric response of multilayered unsaturated media subjected to steady-state and moving harmonic loads using a combination of the extended precise integration method and the Hankel inversion transform. Based on the wave equations of unsaturated soil proposed by Xu, 61 several researchers [66][67][68][69][70][71] investigated the dynamic response of pile embedded in unsaturated soil. However, due to the complexity of unsaturated TI soil model and the difficulty in dealing with dynamic problems, the unsaturated soil was assumed to be isotropic.…”

Section: Introductionmentioning

confidence: 99%

Three‐dimensional fundamental solution for unsaturated transversely isotropic half‐space under surface time‐harmonic load

Wang

Zhou

et al. 2023

Num Anal Meth Geomechanics

Self Cite

View full text Add to dashboard Cite

An analytical solution of unsaturated poroelastic transversely isotropic (TI) half‐space under surface time‐harmonic load with consideration of compressibility, viscous and inertial coupling of soil skeleton, pore‐water and pore‐air, as well as the capillary pressure is investigated in this paper. Firstly, the governing equations of unsaturated TI soil are established in cylindrical coordinate system. Then, the displacement function and operator theory are introduced to decouple the general solution. Secondly, Fourier expansion and Hankel transform are applied to the circumferential and radial coordinates, and the integral general solutions of soil skeleton displacement, pore‐water displacement and pressure, pore‐air displacement and pressure, and the total stress components are derived in the transformed domain. Combined with boundary conditions and continuity conditions, the fundamental solution of unsaturated TI half‐space is obtained. Finally, the proposed solution is verified by benchmarking with two existing solutions. The influence of the TI parameters, vibration frequency and the degree of saturation on the dynamic response of unsaturated poroelastic half‐space is investigated.

show abstract

Vertical dynamic impedance of end‐bearing pile groups embedded in homogeneous unsaturated soils

Cited by 27 publications

References 66 publications

Flexible support of a pile embedded in unsaturated soil under Rayleigh waves

Flexible support of a pile embedded in unsaturated soil under Rayleigh waves

Study on the Lateral Dynamic Impedance of Pile Groups in Transversely Isotropic Soil Using Novak’s Plane Model

Three‐dimensional fundamental solution for unsaturated transversely isotropic half‐space under surface time‐harmonic load

Contact Info

Product

Resources

About