Static and Dynamic Laterally Loaded Floating Piles

Kuhlemeyer, Roger L.

doi:10.1061/ajgeb6.0000771

Cited by 97 publications

(9 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…With reference to the second group of methods, numerical solutions to the problem have been published, among others, by Banerjee & Davies (1978), Kulhemeyer (1979), Poulos & Davis (1980), Randolph (1981), Kaynia & Kausel (1982), Budhu & Davis (1987) and El-Marsafawi et al (1992) using a variety of analytical techniques including finite-difference, finiteelement, boundary-element and various hybrid formulations in three dimensions. These methods are mathematically involved and, thereby, not appealing to geotechnical engineers.…”

Section: Introductionmentioning

confidence: 99%

“…The pile is considered a linearly visco-elastic solid cylindrical beam of diameter d, Young's modulus E p and linear hysteretic damping p . It is also assumed that the pile is sufficiently long so that it deforms only up to a certain depth, L aknown in the literature as "active length", which is typically on the order of ten pile diameters (Kulhemeyer 1979;Randolph 1981). The soil is modeled as a linearly viscoelastic medium of Young's modulus E s , Poisson's ratio , mass density ρ s , and linear hysteretic damping s .…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Horizontal Stiffness and Damping of Piles in Inhomogeneous Soil

Karatzia

Mylonakis

2017

J. Geotech. Geoenviron. Eng.

View full text Add to dashboard Cite

A practically-oriented analytical procedure for determining the dynamic stiffness and damping (impedance coefficients) of a laterally-loaded pile in soil exhibiting different types of inhomogeneity with depth, is presented. To this end, an energy method based on the Winkler model of soil reaction in conjunction with pertinent shape functions for the deflected shape of the pile, are employed. A new elastodynamic model for the wave field around a pile is also introduced. The method is self-standing and free of empirical formulae or constants.Dimensionless closed-form solutions are derived for: (1) the distributed (Winkler) springs and dashpots along the pile; (2) the dynamic stiffness and damping coefficients at the pile head; (3) the "active" length beyond which the pile can be treated as infinitely long; (4) the relative contributions to the overall head stiffness and damping of the soil and the pile media.Swaying, rocking and cross swaying-rocking impedances are considered for parabolic, exponential, and multi-layered inhomogeneous soil. The predictions of the model compare favorably with established solutions, while new results are presented. An illustrative example is provided.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Horizontal Stiffness and Damping of Piles in Inhomogeneous Soil

Karatzia

Mylonakis

2017

J. Geotech. Geoenviron. Eng.

View full text Add to dashboard Cite

show abstract

“…K uhlemeyer [6,7] is credited with one of the rst rigorous analyses of a single pile. This model uses an axisymmetric nite element method (F EM ) in conjunction with non-re ecting boundaries to minimize errors due to spurious wave re ections from the arti cial boundary of the soil.…”

Section: Review Of Existing Pile Modelsmentioning

confidence: 99%

A computationally efficient piled-foundation model for studying the effects of ground-borne vibration on buildings

Talbot

Hunt

2003

Proceedings of the Institution of Mechanical Engineers, Part C:

View full text Add to dashboard Cite

Understanding the effects of ground-borne vibration on buildings is becoming increasingly important as pressure grows to construct high-quality buildings on existing urban sites, which are often close to busy roads or railways. The motivation behind the work presented here is the development of a computational model that enables engineers to evaluate the effectiveness of isolating buildings. This paper presents one component of such a model, namely a new three-dimensional model for modelling the propagation of ground-borne vibration through a piled foundation. A row of piles is considered, with the piles modelled using the solutions for an elastic bar and Euler beam, and the soil represented by an elastic half-space. The model is comprehensive in that it accounts for the longitudinal and transverse motion of the piles due to both external pile-head loads and interaction between neighbouring piles through wave propagation in the surrounding soil. Computational efficiency is achieved by assuming that the row comprises an infinite number of identical piles and using a combination of the boundary element method and periodic structure theory.

show abstract

“…The response of a pile to external excitation, and the associated stiffness and damping, are controlled by the interaction between the elastic pile and the surrounding soil can be theoretically studied on the basis of either discrete or continuous models. A variety of theoretical methods have been developed for the dynamic analysis of piles under lateral loads (Tajimi, 1969;Penzien, 1970;Novak, 1974;Wolf and Von Arx, 1978;Kuhlemeyer, 1979;Kaynia and Kausel, 1982;Sanchez Salinero, 1982Sen et al, 1985;Sharnouby and Novak, 1986;. Two important families of methods use finite and boundary elements which treat the soil as a continuum and are used extensively in research.…”

Section: Introductionmentioning

confidence: 99%

“…The significance of interaction phenomenon in the analysis increases taking into account than kinematic and inertial mechanisms are not synchronous, for which a pertinent summation rule of the corresponding maximum adverse effects on piles and superstructure is additionally required. Theoretical treatment of kinematic pile -soil interaction has received great attention from several researcher, among whom Margason and Holloway (1977); Kuhlemeyer (1979); Krishnan et al (1983); Novak (1991); Gazetas et al (1992); Pender (1993); Kaynia and Mahzooni (1996); Wu and Finn (1997) interest (Meymand, 1998;Dihoru et al, 2009Dihoru et al, , 2010, physical modeling has long been established as a powerful tool for studying seismic pile-soil-superstructure interaction and providing a deeper understanding into the complex physics of dynamic interplay between pile and soil. While strain gauge measures from instrumented piles under real buildings of different vibrational characteristics subjected to actual earthquake motions would be ideal, such data are rare due to high cost and the unpredictable nature of earthquake occurrence.…”

Section: Introductionmentioning

confidence: 99%

Contribution to kinematic and inertial analysis of piles by analytical and experimental methods

Ανωγιάτης¹

View full text Add to dashboard Cite

The problem of pile - soil interaction is examined in the Thesis at hand by means of both theoretical analyses and experimental investigations. Pile foundations in seismically prone areas are subjected to both direct loading, such as axial and lateral forces imposed at their heads, resulting from a phenomenon known as inertial interaction, and indirect loading along their body, such as imposed displacements due to the passage of various types of seismic waves, resulting from a phenomenon known as kinematic interaction. Along this vein, a family of analytical models of the Tajimi type are presented in the framework of linear elastodynamic theory to explore the effects of axial and lateral pile - soil interaction in homogeneous and inhomogeneous soil under static and dynamic (kinematic and inertial) loading. Apart from simplified two-dimensional models of the Baranov - Novak type, few analytical solutions are available to tackle these problems in three dimensions, the majority of which are restricted to the analysis of an elastic half space under static conditions.The proposed models are based on a continuum solution pioneered by Japanese investigators (notably Matuso & Ohara and Tajimi) in the 1960’s. In the realm of this approach the soil is modelled as a continuum, while the pile is conveniently modelled as a rod or a beam by strength-of-materials theory. Displacements and stresses are expressed through Fourier series in terms of the natural modes of the soil medium.Fundamental to the analysis presented in this study is that the influence of horizontal soil displacement on axial pile response and vertical displacement on lateral response, respectively, are negligible. However, their effect on stresses is not negligible which differentiates the proposed models from the classical Tajimi solutions in which the aforementioned displacements are set equal to zero. The above approximations are attractive, as they lead to a straightforward uncoupling of the equations of motions, even in inhomogeneous media, unlike the classical elastodynamic theory where the uncoupling is generally impossible in presence of inhomogeneity.Although approximate, the proposed models are advantageous over available analytical models and rigorous numerical schemes, as they require relative simple computations and provide excellent predictions of pile response at the frequency ranges of interest in earthquake engineering and geotechnics. In addition, they are advantageous over existing simplified analytical approaches of the Winkler type, as they are more accurate, self - standing, free of empirical constants and provide more realistic simulation of the problem. The main advantage over numerical methods (finite and boundary elements) lies in the derivation of the solution in closed form and the elucidation of complex mechanisms related to the dynamic interaction phenomenon, such as radiation damping and wave propagation in in homogeneous media.The main goal of the theoretical effort lies in the derivation of solutions in closed - form for: (i) the static stiffness and the dynamic impedances (dynamic stiffness and damping coefficients) at the pile head, (ii) translational and rotational kinematic response factors (pile head displacement or rotation over free-field response), (iii) actual, depth- dependent, Winkler moduli (spring and damping coefficients), (iv) corresponding average, depth- independent, Winkler moduli to match the pile head stiffness. In addition, simple approximate formulae for Winkler moduli to be used in engineering practice are proposed, to improve the predictions of Winkler models.Pile-to-pile interaction is investigated on the basis of the superposition method for axially loaded piles. Closed-form expressions for attenuation functions are derived to be used individually or in conjunction with more elaborate methods providing more accurate predictions for static and dynamic interaction factors to assess the vertical stiffness of pile groups. New dimensionless frequency ratios controlling pile response are introduced.Finally, new solutions are added in the context of analytical Winkler models for investigating the behaviour of piles under kinematic loading due to vertically-propagating S waves. Emphasis is given on the influence of boundary conditions of the pile. With reference to kinematic pile bending, insight into the physics of the problem is gained through a rigorous superposition scheme involving an infinitely-long pile excited kinematically, and a pile of finite length excited by a concentrated force and a moment at the tip. Contrary to the classical elastodynamic theory where pile response is governed by six dimensionless ratios, in the realm of Winkler theory three only ratios suffice to fully describe the interaction problem, from which the mechanical slenderness and the effective dimensionless frequency are introduced for the first time. The selection of an appropriate value for the Winkler modulus in the accuracy of the kinematic Winkler model is demonstrated.The theoretical results are compared to new experimental data obtained from a series of tests on piles carried out on scaled models performed on the shaking table at University of Bristol Laboratory (BLADE) within the framework of the Seismic Engineering Research Infrastructures (SERIES) program, sponsored by FP7, and contribute in the investigation of pile - soil interaction.

show abstract

Static and Dynamic Laterally Loaded Floating Piles

Cited by 97 publications

References 0 publications

Horizontal Stiffness and Damping of Piles in Inhomogeneous Soil

Horizontal Stiffness and Damping of Piles in Inhomogeneous Soil

A computationally efficient piled-foundation model for studying the effects of ground-borne vibration on buildings

Contribution to kinematic and inertial analysis of piles by analytical and experimental methods

Contact Info

Product

Resources

About