ZSoil 2020 – New Features

New constitutive model for soils HSBrick

  • The new HSBrick is a new approach to deal with the small strain stiffness
  • The original formulation – HSS – is still supported in ZSoil 2020
  • Spurious effect of small strain stiffness increases due to small unloading cycles is eliminated
  • The previous formulation HSS is still available but in the new implementation (some differences in results may appear between ZSoil v2018 and v2020 HSS)
  • HSBrick eliminates any round-off errors and convergence issues due to stiffness oscillations
  • HSBrick behavior is significantly better than HSS in transient dynamics but also all transient analyses

References:  M. Cudny & A. Truty (2020) Refinement of the Hardening Soil model within the small strain range, Acta Geotechnica

Incorrect behavior of HSS upon small unloadings

Spurious effect of small strain stiffness increases due to small unloading cycles



The same behavior of HSS and HSBrick while plastic straining



HSS vs HSBrick for OCR > 1
Brick concept + HS model => HSBrick
Element test: a non-symmetric shakedown

Comparison of HSS and HSBrick in the triaxial test consditions


Dynamics: shear layer : txy – gxy at depth 6.9 m

New creep+aging module for damage plasticity model for concrete

  • Creep+aging module developed in ZSoil 2016 is supported in ZSoil 2020
  • The new module is visible in ZSoil GUI as EC2:2008 (enhanced)
  • It is strongly recommended to start using this new module
New fully consistent visco-elastic aging and creep coupled with damage plasticty
Nonlinear creep in compression (not enough with respect to the EC2)

See more details in ZSoil Day 2019 presentation: Enhanced modeling of creep and aging in damage plasticity model for concrete


New 3D template: Soldier pile wall

  • HSBrick replaces HSS in all templates released as 2020 versions
  • ZSSoldierPileWall is a true 3D FE calculator designed for soldier pile walls, which takes into account local arching effects
  • Previous ZSWalls 2D template is upgraded with new features

For detai, see ZSsoildierPileWall

New options in VirtualLab