3D dynamic responses of a multi-layered transversely isotropic saturated half-space under concentrated forces and pore pressure

This paper investigates three‐dimensional (3D) transient responses of stratified transversely isotropic (TI) saturated media. Firstly, we transform the partial differential equations in Cartesian coordinates into ordinary differential equations (ODEs) for the convenience of solving. Then, we consider the transient load forms and apply the extended precise integration method (EPIM) to study the response of stratified TI saturated media. This paper involves the transverse isotropy of solid constituent, the permeable anisotropy of pore fluid, and various load forms including concentrated loadings and uniform rectangular loadings. The solution in the physical domain can be obtained through the numerical inversion of Laplace‐Fourier transform. Several examples are set up to verify the proposed theory and to investigate the influences of the transverse isotropy of solid constituent, the permeable anisotropy of pore fluid and the stratification of media.

Section: Introductionmentioning

confidence: 99%

Three‐dimensional dynamic response of transversely isotropic saturated media subjected to transient loads

Zhao

2022

“…Zhang and Pan 36 obtained the displacement and pore pressure of the layered TI saturated halfspace caused by circular embedded loads with the consideration of different drainage conditions. Ba et al 37 and Wang et al 38 derived the solution for the layered TI saturated half-space generated by various point loads by dynamic Green's functions.…”

Section: Introductionmentioning

confidence: 99%

Dynamic behaviour of layered transversely isotropic poroelastic media subjected to rectangular harmonic loads

2022

This paper aims to investigate the dynamic behaviour of layered transversely isotropic (TI) poroelastic media subjected to rectangular harmonic loads. First, governing equations of a medium layer derived from Biot's dynamic theory of porous media and constitutive equations of TI materials are converted into the ordinary differential domain by means of integral transform techniques. Next, by introducing boundary and load conditions, the extended precise integration method (PIM) is applied to obtain the solution for a multi-layered system. Then, after an inverse integral treatment, the numerical results in the physical domain are verified with published work, and some examples are designed to unravel the effect of transverse isotropy, load frequencies and stratification on the dynamic behaviour of media.

“…Nevertheless, the problem of a dynamic load applied directly to a TI or anisotropic foundation has been extensively investigated in recent years. [36][37][38][39][40][41][42][43][44] The subsoils were modeled as solely one type of TI medium in these works, namely, as a TI elastic or poroelastic half-space. However, the distribution of the groundwater in the foundation is very complicated, which results in the complexities of the water content and saturation of different soils.…”

Section: Introductionmentioning

confidence: 99%

“…Researches on the dynamic response of a beam coupled with a TI half‐space are quite limited according to the above literature review. Nevertheless, the problem of a dynamic load applied directly to a TI or anisotropic foundation has been extensively investigated in recent years 36–44 . The subsoils were modeled as solely one type of TI medium in these works, namely, as a TI elastic or poroelastic half‐space.…”

Section: Introductionmentioning

confidence: 99%

Moving load response of an axially loaded Timoshenko beam on a multilayered transversely isotropic half‐space comprising different media

Feng

Chen

2020

This paper investigates the dynamic response of an axially loaded Timoshenko beam coupled with a multilayered transversely isotropic (TI) half-space subjected to a moving load. An axial force induced by the thermal expansion is taken into account in the Timoshenko beam. The half-space considers the alternate distribution of an arbitrary number of TI elastic and poroelastic layers to model foundation soils with different properties and moisture conditions. To solve the governing equations, Fourier transform is adopted. The stratified foundation is formulated by extending an "adapted stiffness matrix method" to a more general scenario with an arbitrary number of layers. The beam is then coupled with the foundation to derive solutions to the system in the frequency-wavenumber domain. The final results in the time-spatial domain are recovered by the inverse Fourier transform. After confirming the accuracy of the method in this study, the influences of the pore water existence, the transverse isotropy of different parameters, and the axial force are investigated. It can be observed that the effect of pore water existence on the maximum beam deflection can reach 22% in this study. The transverse isotropy of the elastic and shear moduli influences the critical speed of the beam deflection by altering the phase velocity of the first wave propagation mode of the beam-foundation system. The vertical permeability coefficient is more important than the horizontal one in determining the excess pore pressure. The rise of the beam temperature (axial force) decreases the critical speed and magnifies the vibrations.