2024

Upcoming

The next upcoming release will include:

Graphical User Interface

We are proud to announce that numgeo now integrates into the Pre-Processor GiD! See GUI

Features:

• Initial state
  • A new initial stress type type=full is now available allowing to prescribe all components of the stress tensor individually
• Solver
  • It is now possible to omit the use of a linear equation solver (see *Step definition).
• Early termination:
  • Define target stresses/strains for specific elements that lead to early termination of the step once they are exceeded. See Early termination

Manuals:

• Revised tutorial on element test simulations
• Added new initial stress type to *Initial conditions, type=stress

General modifications:

Resolved bugs:

• Bugfix in Karlsruhe Hydraulic model for update of the degree of saturation

May 2024

The release notes for May 2024 are:

Features:

• Elements

  • Is is now possible to define the stabilisation parameter \(\alpha\) for stabilized u-p elements for saturated soils and partially saturated soils via keyword.
  • It is now possible to consider Cavitation (only available for u-p-sat elements yet)

• Procedures

  • It is now possible to scale the critical time increment in explicit dynamics as explained in the step definition.

• Load

  • Added dampers to connector elements in order to use them as spring-damper elements.

• Constitutive models

  • The HCA implementation now allows to consider different definitions of the cyclic history variable \(g^A\).

Manuals:

• Added documentation for FPL-Stabilisation
• Added benchmark for Hertzian Contact in 3D
• Added documentation for Bishop effective stress
• Revised installation instructions

General modifications:

• Tangential stiffness factor is now five times lower in case the default stiffness, which depends on the material stiffness, is used

• Some Abaqus-specific keywords such as *Heading or *Preprint can now be read. In addition, some of the most common 3D element type names of Abaqus are now automatically (internally) changed to the corresponding element type names used in numgeo, which are C3D20/C3D20R = U20-SOLID , C3D8R = U8-SOLID-3D-RED and C3D8 = U8-SOLID-3D

Resolved bugs:

• Output variable CON_F is now written for all nodes of the node set used in the Connector element definition, not just for the first node of the set
• Bugfix of 3D contact in case contact points have a large distance and should not be considered
• Bugfix for calculation of tangential stiffness factor being too low for elements with larger number of integration points

March 2024

The release notes for March 2024 are:

General modifications:

• Revised parts of the code that required the use of \heap-arrays:0 for large FE models on Windows. Performance gains by a factor of up to 5 are observed for large models with the new version of numgeo.

Features:

• Constitutive models
  • SANISAND-MFs: All parameters are now available in the interface of the model, including the ones whose default values rarely need to be changed.

Manuals:

• Revised installation instructions for Windows
• Added documentation for Sanisand-MSf

February 2024

The release notes for February 2024 are:

Features:

• Procedures

  • It is now possible to automatically transfer linear interpolated brick elements with 8 nodes to tri-quadratic interpolated brick elements with 27 nodes
  • Mixed Implicit/Explicit time integration

• Elements

  • Explicit u-U elements, see Reference Manual
  • Stabilized u-p elements for saturated soils, see Reference Manual
  • Stabilized u-p elements for partially saturated soils, see Reference Manual

• Constitutive models

  • The HCA implementation now allows to consider multiple strain amplitudes during the high-cycle phase. Length of statev vector reduced to save some RAM.
  • Reimplementation of the Hypo+ISA model
  • Added centered-step-size approximation of the partial derivative of the degree of saturation w.r.t. the capillary pressure \((\partial S^e)/(\partial p_c)\)
  • New model: SANISAND-F
  • New model: SANISAND-MFs

• Contact

  • Special check for non-converged contact points allowing for better handling of contact points with large distance
  • Improved handling of kinks in surfaces

• Loads

  • Reduced integration order of load for reduced integrated elements

Resolved bugs:

• Bugfix in transparent boundary conditions for 3D elements
• Fixed bug if shell/batch script not existing for user amplitude and user contact
• Fixed bug in the windows version of the user load file

General modifications:

• Improved numerical stability in infiltration processes
• Added statically linked numgeo version
• Default convergence controls are now of type dof-based, see Reference Manual or the Theory Manual

Corrections Keywords Manual:

• Updated default values for maximum number of iterations and convergence criteria