Definition of load transfer curves of piles in granitic residual soil
DOI:
https://doi.org/10.24849/j.geot.2014.130.04Keywords:
Load transfer, Deep foundations, Residual loads, Modelling in residual soilsAbstract
The subsurface of North-Western Portugal, in particular the city of Oporto, is composed mainly of granite residual soil, characterized by its strong heterogeneity. Due to developments in construction, the use of piles has been increasingly frequent in this type of soil. Therefore, it becomes imperative the knowledge of the behaviour of this type of foundation that, even today, is not consensual. A simplified method, but also effective, is to analyse the stress-strain behaviour along the shaft interface and in the bottom (toe) support by recurring to load-transfer curves, commonly known as ‘t-z’ and ‘q-z’, respectively. Given the problem of residual loads, it is the objective of this study to show the possibilities based on the definition of the curves that characterize the behaviour of three types of pile in this type of soil, also considering the effect of the residual load. To simulate these curves a very comprehensive commercial program, UniPile® of Unisoft, has been used. It is hoped that this study provides practical and very useful information for a more effective but also safer design of piles in this type of soil, taking into account the different factors that influence their behaviour.
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References
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