Acta Geotechnica

, Volume 13, Issue 2, pp 399–417 | Cite as

Creep behaviour of intact and remoulded fibrous peat

  • Mohan P. Acharya
  • Michael T. Hendry
  • C. Derek Martin
Research Paper


This paper presents the creep behaviour of intact and remoulded specimens of fibrous peat obtained from a field site near Anzac, Alberta, Canada. The creep behaviour was investigated by means of long-term drained and undrained triaxial tests. The development of volumetric, axial, and undrained axial strain and strain rate during drained and undrained creep tests under variable stress conditions is presented. The stress strain strain rate (p′ε v\(\dot{\varepsilon }_{\text{v}}\)) relationship is found to be unique for different stress and loading durations. The p′ε v\(\dot{\varepsilon }_{\text{v}}\) relationship is analysed and represented by creep isotaches. The applicability of different creep models developed for normally consolidated clay is discussed and applied to define the development of creep strain in fibrous peat under varying isotropic and deviator stresses. The secondary consolidation coefficient for evaluating the volumetric strain rate of peat is found to be applicable with some limits. The drained creep behaviour of remoulded peat specimens differs from the behaviour shown by Shelby tube specimens, whereas the undrained creep behaviour in remoulded and Shelby tube specimens is similar.


Creep test Fibrous peat Strain and strain rate Stress Triaxial test 

List of symbol


Coefficient of compression


Coefficient of secondary compression


One-dimensional compression


Preconsolidation pressure


Mean confining pressure

\(\dot{p}{\prime }\)

Rate of effective stress


Deviator stress \((\sigma_1 - \sigma_3)\)


First deviator stress applied (kPa)


Deviator stress increment


Effective confining stress


Confining stress increment


Stress increment in 1D compression


Stress increment ratio (Δq/q or Δσ3 3)


Initial water content of specimen


Water content at the end of the creep tests


Density of specimen (g/cm3)


Volumetric strain at the end of the pre-consolidation


Initial void ratio


Volumetric strain

\(\dot{\varepsilon }_{\text{v}}\)

Volumetric strain rate


Axial strain

\(\dot{\varepsilon }_{a}\)

Axial strain rate


Undrained axial strain

\(\dot{\varepsilon }_{\text{ad}}\)

Undrained strain rate


Increase in pore pressure

α, β

Creep parameters


Slope of log \(\dot{\varepsilon }_{v}\) − log t plot (the rate of decrease in strain rate)


Lateral strain


Poisson’s ratio



The authors acknowledge the contribution of Canadian National Railways for providing both the project and funding support. This research was made possible through the (Canadian) Railway Ground Hazard Research Program and the Canadian Rail Research Laboratory (, both of which are supported by the Natural Sciences and Engineering Research Council of Canada (NSERC), CPR, CN, American Association of Railroads Transportation Technology Center Inc. (AAR/TTCI) and Transport Canada; and an NSERC Discovery Grant.

Supplementary material

11440_2017_545_MOESM1_ESM.docx (348 kb)
Supplementary material 1 (DOCX 348 kb)


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Copyright information

© Springer-Verlag Berlin Heidelberg 2017

Authors and Affiliations

  • Mohan P. Acharya
    • 1
  • Michael T. Hendry
    • 1
  • C. Derek Martin
    • 1
  1. 1.Markin/CNRL Natural Resources Engineering FacilityUniversity of AlbertaEdmontonCanada

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