Cyclic and Rapid Axial Load Tests on Displacement Piles in Soft Clay

Files in This Item:
File Description SizeFormat 
Axial cyclic and rapid load tests on displacement piles in soft clay.pdf467.87 kBAdobe PDFDownload
Title: Cyclic and Rapid Axial Load Tests on Displacement Piles in Soft Clay
Authors: Doherty, Paul
Gavin, Kenneth
Permanent link:
Date: Aug-2012
Abstract: Offshore piles are subjected to complex loading regimes, which include both rapidly applied static and cyclic loads. This note describes an experimental investigation conducted in order to assess the factors influencing the response of offshore piles to these loading conditions. The tests were performed using instrumented model piles installed in soft clay. During cyclic loading, the piles demonstrated a transition from stable to unstable behaviour when the applied loads reached a specific load threshold. Stable behaviour was defined when increments of plastic displacement decreased as the number of load cycles increased. During stable behaviour, radial effective stresses at the pile-soil interface remained constant. During unstable behaviour, pore pressures at the pile-soil interface rose as the number of cycles increased. This resulted in reduced radial effective stresses and progressively increasing displacement rates. Due to the presence of these excess pore pressures, the shaft resistance recorded during static load tests, performed after a period of unstable cyclic loading, were lower than those measured on piles where the pore pressure was fully equalised. However, the axial resistance was seen to be rate dependent. Fast loading of the pile resulted in reductions of pore water pressure at the soil-pile interface and enhanced shaft resistance which could overcome the negative effect caused by cyclic loading.
Type of material: Journal Article
Publisher: ASCE
Copyright (published version): 2012, ASCE
Keywords: FoundationsPilesTestingCyclic loadingOffshore loadingPore pressure
DOI: 10.1061/(ASCE)GT.1943-5606.0000655
Language: en
Status of Item: Peer reviewed
Appears in Collections:Civil Engineering Research Collection

Show full item record

Citations 50

Last Week
Last month
checked on Aug 9, 2018

Google ScholarTM



This item is available under the Attribution-NonCommercial-NoDerivs 3.0 Ireland. No item may be reproduced for commercial purposes. For other possible restrictions on use please refer to the publisher's URL where this is made available, or to notes contained in the item itself. Other terms may apply.