CHD pile performance, part II: Numerical modelling

TY - JOUR

T1 - CHD pile performance, part II

T2 - Numerical modelling

AU - Knappett, Jonathan Adam

AU - Caucis, Karlis

AU - Brown, Michael John

AU - Jeffrey, John Ross

AU - Ball, Jonathan David

N1 - The fourth author would like to acknowledge the financial support of the Engineering and Physical Sciences Research Council (EPSRC) (funding code CASE/CAN/07/03). The authors are grateful for the additional financial and technical support provided by Roger Bullivant Ltd.

PY - 2016/10

Y1 - 2016/10

N2 - In this paper, a set of simple modelling procedures are presented that can be used to estimate the load-settlement behaviour of Continuous Helical Displacement (CHD) piles in sands, in conjunction with the Finite Element Method (FEM). The approach makes use of a stress and strain dependent non-linear soil model that can be parameterised using basic soil data (principally relative density) that can be determined through routine site investigation (e.g. SPT, CPT). The procedures are validated against a database of 1-g physical model tests reported in the Companion Paper, where they are shown to be suitable for estimating the load-settlement behaviour of CHD piles within the serviceability range. In this way they are complimentary to the analytical method for estimating the ultimate capacity of a CHD pile which was developed in the Companion Paper. In the final part of the paper, the FEM and analytical model are applied to four historical field pile load tests on CHD piles conducted at three different sand sites where they are (i) further validated; and (ii) used to discuss potential savings in pile material and therefore cost due to additional confidence in performance determination at both ultimate and serviceability limiting states.

AB - In this paper, a set of simple modelling procedures are presented that can be used to estimate the load-settlement behaviour of Continuous Helical Displacement (CHD) piles in sands, in conjunction with the Finite Element Method (FEM). The approach makes use of a stress and strain dependent non-linear soil model that can be parameterised using basic soil data (principally relative density) that can be determined through routine site investigation (e.g. SPT, CPT). The procedures are validated against a database of 1-g physical model tests reported in the Companion Paper, where they are shown to be suitable for estimating the load-settlement behaviour of CHD piles within the serviceability range. In this way they are complimentary to the analytical method for estimating the ultimate capacity of a CHD pile which was developed in the Companion Paper. In the final part of the paper, the FEM and analytical model are applied to four historical field pile load tests on CHD piles conducted at three different sand sites where they are (i) further validated; and (ii) used to discuss potential savings in pile material and therefore cost due to additional confidence in performance determination at both ultimate and serviceability limiting states.

KW - Geotechnical engineering

KW - Piles and piling

KW - Models (numerical)

UR - http://www.icevirtuallibrary.com/doi/abs/10.1680/jgeen.15.00132

U2 - 10.1680/jgeen.15.00132

DO - 10.1680/jgeen.15.00132

M3 - Article

SN - 1353-2618

VL - 169

SP - 436

EP - 454

JO - Proceedings of the Institution of Civil Engineers: Geotechnical Engineering

JF - Proceedings of the Institution of Civil Engineers: Geotechnical Engineering

IS - 5

ER -