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Faculty of EngineeringDepartment of Civil and Environmental Engineering

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BibTex format

author = {Nicholson, DP and Jardine, RJ},
doi = {10.1680/geot.1981.31.1.67},
journal = {Geotechnique},
pages = {67--90},
title = {Performance of vertical drains at Queenborough bypass},
url = {},
volume = {31},
year = {1981}

RIS format (EndNote, RefMan)

AB - The bypass round the town of Queenborough on the Isle of Sheppey, Kent is constructed on soft alluvial clay up to 10 m deep. Where the bypass bridges an existing railway line the approach embankments rise to a height of 7 m above the existing marshland. Embankment construction was started in 1976, but instrument readings indicated that the initial stage of filling could not safely be constructed higher than 30 m. Further site investigations were made which included in situ constant head permeability tests performed by reducing the pore pressure at the piezometer cell using recently developed equipment. Analysis showed that vertical drains would be required to accelerate the consolidation and enable the embankment to be completed within the remaining construction programme. Subsequently, two types of vertical drains were assessed during trials in 1978: a 65 mm dia. Sandwick drain and a 300 mm wide AV Colbond fabric strip drain. The Paper compares the consolidation parameters and settlements predicted from laboratory and in situ tests with the field performance of the embankment with and without the vertical drains. Good agreement was found between these comparisons which confirm the predicted decrease in coefficient of consolidation as effective stress exceeded the preconsolidation pressure. © 1981, Thomas Telford Ltd. All rights reserved.
AU - Nicholson,DP
AU - Jardine,RJ
DO - 10.1680/geot.1981.31.1.67
EP - 90
PY - 1981///
SN - 0016-8505
SP - 67
TI - Performance of vertical drains at Queenborough bypass
T2 - Geotechnique
UR -
VL - 31
ER -