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Pile Groups (pile + groups)

Distribution by Scientific Domains

Engineering	100%

Selected Abstracts

Dynamic stiffness of deep foundations with inclined piles

EARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 12 2010
L. A. Padrón
Abstract The influence of inclined piles on the dynamic response of deep foundations and superstructures is still not well understood and needs further research. For this reason, impedance functions of deep foundations with inclined piles, obtained numerically from a boundary element,finite element coupling model, are provided in this paper. More precisely, vertical, horizontal, rocking and horizontal,rocking crossed dynamic stiffness and damping functions of single inclined piles and 2 × 2 and 3 × 3 pile groups with battered elements are presented in a set of plots. The soil is assumed to be a homogeneous viscoelastic isotropic half-space and the piles are modeled as elastic compressible Euler,Bernoulli beams. The results for different pile group configurations, pile,soil stiffness ratios and rake angles are presented. Copyright © 2010 John Wiley & Sons, Ltd. [source]

Response evaluation of axially loaded fixed-head pile groups in clayey soils

INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 17 2009
Emilios M. Comodromos
Abstract The aim of this paper is to investigate the interaction between the piles in a group with a rigid head and correlate the response of a group of piles to that of a single pile. For this purpose, a computationally intensive study using 3-D nonlinear numerical analysis was carried out for different pile group arrangements in clayey soils. The responses of the groups of piles were compared with that of a single pile and the variation of the settlement amplification factor Ra was then quantified. The influence of the number of piles, the spacing, and the settlement level on the group response is discussed. A previously proposed relationship for predicting the response of a pile group, based on its configuration and the response of a single pile, has been modified to extend its applicability for any pile spacing. The modified relationship provides a reasonable prediction for various group configurations in clayey soils. Copyright © 2009 John Wiley & Sons, Ltd. [source]

Nonlinear response of laterally loaded piles and pile groups

INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 7 2009
Wei Dong Guo
Abstract In spite of extensive studies on laterally loaded piles carried out over years, none of them offers an expedite approach as to gaining the nonlinear response and its associated depth of mobilization of limiting force along each pile in a group. To serve such a need, elastic,plastic solutions for free-head, laterally loaded piles were developed recently by the author. They allow the response to be readily computed from elastic state right up to failure, by assigning a series of slip depths, and a limiting force profile. In this paper, equivalent solutions for fixed-head (FixH) single piles were developed. They are subsequently extended to cater for response of pile groups by incorporating p -multipliers. The newly established solutions were substantiated by existing numerical solutions for piles and pile groups. They offer satisfactory prediction of the nonlinear response of all the 6 single piles and 24 pile groups investigated so far after properly considering the impact of semi-FixH restraints. They also offer the extent to ultimate state of pile groups via the evaluated slip depths. The study allows ad hoc guidelines to be established for determining input parameters for the solutions. The solutions are tailored for routine prediction of the nonlinear interaction of laterally loaded FixH piles and capped pile groups. Copyright © 2008 John Wiley & Sons, Ltd. [source]

A modulus-multiplier approach for non-linear analysis of laterally loaded pile groups

INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 9 2007
Chia-Cheng Fan
Abstract A modulus-multiplier approach, which applies a reduction factor to the modulus of single pile p,y curves to account for the group effect, is presented for analysing the response of each individual pile in a laterally loaded pile group with any geometric arrangement based on non-linear pile,soil,pile interaction. The pile,soil,pile interaction is conducted using a 3D non-linear finite element approach. The interaction effect between piles under various loading directions is investigated in this paper. Group effects can be neglected at a pile spacing of 9 times the pile diameter for piles along the direction of the lateral load and at a pile spacing of 6 times the pile diameter for piles normal to the direction of loading. The modulus multipliers for a pair of piles are developed as a function of pile spacing for departure angle of 0, 90, and 180sup>/sup> with respect to the loading direction. The procedure proposed for computing the response of any individual pile within a pile group is verified using two well-documented full-scale pile load tests. Copyright © 2006 John Wiley & Sons, Ltd. [source]

A simplified analysis method for piled raft foundations in non-homogeneous soils

INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 2 2003
Pastsakorn Kitiyodom
Abstract A simplified method of numerical analysis based on elasticity theory has been developed for the analysis of axially and laterally loaded piled raft foundations embedded in non-homogeneous soils and incorporated into a computer program "PRAB". In this method, a hybrid model is employed in which the flexible raft is modelled as thin plates and the piles as elastic beams and the soil is treated as springs. The interactions between structural members, pile,soil,pile, pile,soil,raft and raft,soil,raft interactions, are approximated based on Mindlin's solutions for both vertical and lateral forces with consideration of non-homogeneous soils. The validity of the proposed method is verified through comparisons with some published solutions for single piles, pile groups and capped pile groups in non-homogeneous soils. Thereafter, the solutions from this approach for the analysis of axially and laterally loaded 4-pile pile groups and 4-pile piled rafts embedded in finite homogeneous and non-homogeneous soil layers are compared with those from three-dimensional finite element analysis. Good agreement between the present approach and the more rigorous finite element approach is demonstrated. Copyright © 2002 John Wiley & Sons, Ltd. [source]

Dynamische Steifigkeit und Dämpfung von Pfahlgruppen

BAUTECHNIK, Issue 2 2009
Hamid Sadegh-Azar Dr.-Ing.
Geotechnik; Bodenmechanik Abstract In diesem Beitrag werden die dynamische Steifigkeit und Dämpfung von Pfahlgruppen und ihre Auswirkung auf die Auslegung und Wirtschaftlichkeit der Pfahlgründung selbst und der Bauwerke darauf untersucht. Die Berechungen werden mit der sogenannten "Thin-Layer-Method", einer sehr leistungsfähigen Berechnungsmethode im Frequenzbereich, durchgeführt (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) Dynamic stiffness and damping properties of pile groups. The dynamic stiffness and damping properties of pile-groups have been investigated in this paper. Also, the substantial influence of these properties on an economic structure and foundation design is demonstrated. The analysis has been carried out using the "Thin-Layer-Method", which is a very efficient and powerful analysis procedure in frequency domain. [source]