Dynamic modeling and response of rigid embedded cylinders

Abstract

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Soil reaction to lateral harmonic pile motion

“…It is noted that unlike the vertical response mode where a number of stress-displacement terms are set equal to zero in a corresponding formulation [27], in the solution at hand setting equal to zero is the only approximation involved. It is also worth mentioning that due to this approximation shear stress ceases to be zero at the soil surface, yet this violation typically has a minor effect on the solution [6], [7], [11]. Additional discussion is provided in the ensuing.…”

“…Our pile is considered a vertical cylinder and the soil is modelled as a continuum, taking into account all three components of soil displacement under the assumption of zero dynamic vertical normal stresses. A similar assumption was adopted in earlier studies [6] [7], however, proposed solutions were limited to the kinematic response of laterally loaded piles. This physically motivated simplification is particularly attractive, as it respects the boundary condition associated with the presence of a stressfree soil surface and reduces the number of governing equations to twoinstead of three as found in the classical elastodynamic theory ( [8], [9]).…”

Dynamic pile impedances for fixed-tip piles

“…piles embedded in shallow rock with / < 10), dimensionless graphs presented in this paper provide an effective tool for quick, preliminary assessment of the importance of SSI effects on the seismic behavior of the superstructure. The authors acknowledge the opportunity to expand this analytical study to treat the 14 kinematic soil-pile interaction problem (vertically propagating harmonic SH waves in the soil medium), for which research has been performed in the past (e.g., [21], [22], [23]). …”

Dynamic pile impedances for laterally–loaded piles using improved Tajimi and Winkler formulations

“…It is noted that unlike the vertical response mode where a number of stress-displacement terms are set equal to zero in a corresponding formulation [27], in the solution at hand setting σ z equal to zero is the only approximation involved. It is also worth mentioning that due to this approximation shear stress τ rz ceases to be zero at the soil surface, yet this violation typically has a minor effect on the solution [6,7,11]. Additional discussion is provided in the ensuing.…”

“…Our pile is considered a vertical cylinder and the soil is modeled as a continuum, taking into account all three components of soil displacement under the assumption of zero dynamic vertical normal stresses. A similar assumption was adopted in earlier studies [6,7], however, proposed solutions were limited to the kinematic response of laterally loaded piles. This physically motivated simplification is particularly attractive, as it respects the boundary condition associated with the presence of a stress -free soil surface and reduces the number of governing equations to two -instead of three as found in the classical elastodynamic theory [8,9].…”