Finite Element Modelling of pile groups founded above compressible layers

Richard Merifield

It is widely accepted that the presence of compressible clay layers beneath pile groups can substantially increase the settlement of a pile group. Furthermore, as the size of the pile group increases this effect is magnified and further complicated by the load distribution across the pile group. A number of simplified methods, such as the equivalent raft or equivalent pier method, are often employed to estimate the settlement of pile groups founded over a compressible layer, however, such methods can lead to both overly conservative and un-conservative results and large variations in results between methods. More recent methods have explored the use of power law functions or energy principles to analyse piles and pile groups in non-homogeneous soil conditions, however, these methods can be difficult to apply in practice. With the availability of modern computers and the advancement of commercially available numerical analyses packages, it is now possible to use the finite element method to analyse pile groups overlying compressible soil layers in order to better understand this problem. This paper presents an extension of previous work by the authors based on the finite element method for use in estimating settlements of pile groups overlying compressible layers. Some dimensionless design charts are provided for a range of commonly encountered geotechnical conditions and pile groups.

About the speaker

Conjoint Professor Richard Merifield

Richard Merifield Principal Geotechnical Engineer at Douglas Partners Pty Ltd
Adjunct Professor of Geotechnical Engineering, University of Newcastle

Richard is a well-regarded expert in applied numerical modelling in geotechnical engineering. His practical and numerical modelling experience has provided many innovative solutions to overcome project challenges and the necessary tools to tackle a wide range problems that currently exist in the geotechnical and mining industries.

Richard has over 50 technical papers published in international journals and conferences. He is also a frequent invited speaker at universities, conferences and technical societies, and a Conjoint Associate Professor at the University of Newcastle.

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