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Factors controlling the seasonal variation in soil water content and pore water pressures within a lightly vegetated clay slope

Smethurst, J.A., Clarke, D. and Powrie, W. (2012) Factors controlling the seasonal variation in soil water content and pore water pressures within a lightly vegetated clay slope Geotechnique, 62, (5), pp. 429-446. (doi:10.1680/geot.10.p.097).

Record type: Article


Seasonal cycles of soil water content cause shrinking and swelling in clay soils that can in turn contribute to strain-softening and progressive failure. This paper presents and analyses six years of field measurements of soil water content and pore water pressures in the upper layers of a lightly vegetated London Clay slope near Newbury, UK. The field observations are set in the context of a 40 year run of rainfall data for the site. Moderately extreme rainfall and drought events were experienced over the period 2003-2008, allowing almost the full variation in likely pore water pressures to be characterised. Pore water pressures were found to return to near hydrostatic during most winters. Variations in summer rainfall, particularly during June-August, are shown to have a large influence on the magnitude of the cycles of pore water pressure and effective stress. The 40 year rainfall dataset is used to calculate approximate return periods for the observed soil conditions and provides a benchmark for calculating the impacts of expected climate change on similar sites.

Text Smethurst_et_al_(2012)_Newbury_2_Geotechnique.pdf - Version of Record
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Published date: May 2012
Keywords: clays, monitoring, pore pressures, slopes, suction, vegetation
Organisations: Infrastructure Group, Civil Engineering & the Environment


Local EPrints ID: 74190
ISSN: 0016-8505
PURE UUID: d21c3e86-fead-4a03-99b4-a21b9876d21c
ORCID for D. Clarke: ORCID iD
ORCID for W. Powrie: ORCID iD

Catalogue record

Date deposited: 11 Mar 2010
Last modified: 03 Oct 2017 16:41

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