Numerical modelling of Haarajoki test embankment on soft clays with and without PVDs


Creative Commons License

YILDIZ A. , UYSAL F.

GEOMECHANICS AND ENGINEERING, cilt.8, ss.707-726, 2015 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 8 Konu: 5
  • Basım Tarihi: 2015
  • Doi Numarası: 10.12989/gae.2015.8.5.707
  • Dergi Adı: GEOMECHANICS AND ENGINEERING
  • Sayfa Sayıları: ss.707-726

Özet

This paper investigates the time dependent behaviour of Haarajoki test embankment on soft structured clay deposit. Half of the embankment is constructed on an area improved with prefabricated vertical drains, while the other half is constructed on the natural deposit without any ground improvement. To analyse the PVD-improved subsoil, axisymmetric vertical drains were converted into equivalent plane strain conditions using three different approaches. The construction and consolidation of the embankment are analysed with the finite element method using a recently developed anisotropic model for time-dependent behaviour of soft clays. The constitutive model, namely ACM-S accounts for combined effects of plastic anisotropy, interparticle bonding and degradation of bonds and creep. For comparison, the problem is also analysed with isotropic Soft Soil Creep and Modified Cam Clay models. The results of the numerical analyses are compared with the field measurements. The results show that neglecting effects of anisotropy, destructuration and creep may lead to inaccurate predictions of soft clay response. Additionally, the numerical results show that the matching methods accurately predict the consolidation behaviour of the embankment on PVD improved soft clays and provide a useful tool for engineering practice.

This paper investigates the time dependent behaviour of Haarajoki test embankment on soft
structured clay deposit. Half of the embankment is constructed on an area improved with prefabricated
vertical drains, while the other half is constructed on the natural deposit without any ground improvement.
To analyse the PVD-improved subsoil, axisymmetric vertical drains were converted into equivalent plane
strain conditions using three different approaches. The construction and consolidation of the embankment
are analysed with the finite element method using a recently developed anisotropic model for timedependent
behaviour of soft clays. The constitutive model, namely ACM-S accounts for combined effects of
plastic anisotropy, interparticle bonding and degradation of bonds and creep. For comparison, the problem is
also analysed with isotropic Soft Soil Creep and Modified Cam Clay models. The results of the numerical
analyses are compared with the field measurements. The results show that neglecting effects of anisotropy,
destructuration and creep may lead to inaccurate predictions of soft clay response. Additionally, the
numerical results show that the matching methods accurately predict the consolidation behaviour of the
embankment on PVD improved soft clays and provide a useful tool for engineering practice.