ISSN: 1945-7545
CODEN: GTJODJ
Published Online: 10 December 2012
Page Count: 12

Laboratory Evaluation of Coefficient of Radial Consolidation Based on Pore-Water-Pressure Dissipation and Settlement

Indraratna, Buddhima
Professor of Civil Engineering, Director, Centre for Geomechanics and Railway Engineering, Faculty of Engineering, Univ. of Wollongong, Wollongong City, NSW
ARC Centre of Excellence for Geotechnical Science and Engineering,

Kianfar, Kourosh
Candidate, Centre for Geomechanics and Railway Engineering, Faculty of Engineering, Univ. of Wollongong, Wollongong City, NSW
ARC Centre of Excellence for Geotechnical Science and Engineering,

Rujikiatkamjorn, Cholachat
Senior Lecturer, Centre for Geomechanics and Railway Engineering, Faculty of Engineering, Univ. of Wollongong, Wollongong City, NSW
Centre of Excellence for Geotechnical Science and Engineering,

(Received 5 March 2012; accepted 19 September 2012)

Abstract

Modified and standard Rowe consolidation cells were employed to investigate the behaviour of soft clays during vacuum assisted radial consolidation. Degree of consolidation (DOC) and the back calculated value of coefficient of radial consolidation (ch) based on measured settlement and excess pore-water-pressure (uw) dissipation curves were compared. The DOC and (ch) based on pore water pressures are shown to be less than those based on settlements. The vacuum pressure-total surcharge ratio (VSR) is found to be an important parameter controlling the rate of the consolidation. Moreover, the coefficient of radial consolidation (ch) based on conventional oedometer testing could not accurately predict the consolidation behaviour of soft soils under varying VSR. Finally, a semi-empirical model incorporating the relationship between VSR and a modified coefficient of radial consolidation is introduced.

Keywords:
coefficient of radial consolidation, consolidation, degree of consolidation, pore water pressure, radial consolidation, settlement, vacuum, vertical drains

Paper ID: GTJ20120032
DOI: 10.1520/GTJ20120032
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