Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Construction of simplified design p-y curves for liquefied soils
In practice, laterally loaded piles are most often modelled using a ‘Beam-on-Nonlinear-Winkler-Foundation’ (BNWF) approach. While well calibrated p-y curves exist for non-liquefied soils (e.g. soft clay and sands), the profession still lacks reliable p-y curves for liquefied soils. In fact, the latter should be consistent with the observed strain-hardening behaviour exhibited by liquefied samples in both element and physical model tests. It is recognised that this unusual strain-hardening behaviour is induced by the tendency of the liquefied soil to dilate upon undrained shearing, which ultimately results in a gradual decrease of excess pore pressure and consequent increase in stiffness and strength. The aim of this paper is twofold. First it proposes an easy-to-use empirical model for constructing stress-strain relationships for liquefied soils. This only requires three soil parameters which can be conveniently determined by means of laboratory tests, such as a cyclic triaxial and cyclic simple shear tests. Secondly, a method is illustrated for the construction of p-y curves for liquefiable soils from the proposed stress-strain model. This involves scaling of stress and strain into compatible soil reaction p and pile deflection y, respectively. The scaling factors for stress and strain axis are computed following an energy-based approach, analogous to the upper-bound method used in classical plasticity theory. Finally, a series of results from centrifuge tests are presented, whereby p-y curves are back-calculated from available experimental data and qualitatively compared with that proposed by the authors.
Construction of simplified design p-y curves for liquefied soils
In practice, laterally loaded piles are most often modelled using a ‘Beam-on-Nonlinear-Winkler-Foundation’ (BNWF) approach. While well calibrated p-y curves exist for non-liquefied soils (e.g. soft clay and sands), the profession still lacks reliable p-y curves for liquefied soils. In fact, the latter should be consistent with the observed strain-hardening behaviour exhibited by liquefied samples in both element and physical model tests. It is recognised that this unusual strain-hardening behaviour is induced by the tendency of the liquefied soil to dilate upon undrained shearing, which ultimately results in a gradual decrease of excess pore pressure and consequent increase in stiffness and strength. The aim of this paper is twofold. First it proposes an easy-to-use empirical model for constructing stress-strain relationships for liquefied soils. This only requires three soil parameters which can be conveniently determined by means of laboratory tests, such as a cyclic triaxial and cyclic simple shear tests. Secondly, a method is illustrated for the construction of p-y curves for liquefiable soils from the proposed stress-strain model. This involves scaling of stress and strain into compatible soil reaction p and pile deflection y, respectively. The scaling factors for stress and strain axis are computed following an energy-based approach, analogous to the upper-bound method used in classical plasticity theory. Finally, a series of results from centrifuge tests are presented, whereby p-y curves are back-calculated from available experimental data and qualitatively compared with that proposed by the authors.
Construction of simplified design p-y curves for liquefied soils
Lombardi, Domenico (Autor:in) / Dash, S.R. (Autor:in) / Bhattacharya, Subhamoy (Autor:in) / Ibraim, Erdin (Autor:in) / Muir Wood, David (Autor:in) / Taylor, Colin (Autor:in)
01.03.2017
Lombardi , D , Dash , S R , Bhattacharya , S , Ibraim , E , Muir Wood , D & Taylor , C 2017 , ' Construction of simplified design p-y curves for liquefied soils ' Geotechnique , vol 67 , no. 3 , pp. 216-227 . DOI:10.1680/jgeot.15.P.116
Aufsatz (Zeitschrift)
Elektronische Ressource
Englisch
DDC:
690
Construction of simplified design p–y curves for liquefied soils
Online Contents | 2017
|Construction of simplified design p–y curves for liquefied soils
Online Contents | 2016
|Simplified Hybrid p-y Spring Model for Liquefied Soils
Online Contents | 2013
|Simplified Hybrid p-y Spring Model for Liquefied Soils
British Library Online Contents | 2013
|