Get to know the MRESS Solid-Shell Element Class

Description of the element's Class; Constructors and Public Methods.

Mesh Convergence Results

Twisted Strip Benchmark: A rigorous convergence test with mesh refinement, comparing Abaqus C3D8 and C3D8i elements with the MRESS API and the Hexa8 API.

Designed to push the limits of element performance under extreme warping, transverse shear, and bending loads.

The MRESS solid-shell API achieves significantly faster convergence compared to Abaqus C3D8 and C3D8I elements as well as the Hexa8 API element. It clearly shows the effect of the EAS on improving MRESS API behaviour under bending.

Explore the gallery for an in-depth analysis of the mesh convergence results.

Pinched Cylinder Benchmark: A renowned test for validating elements in thin-walled structures under bending and transverse shear.

The MRESS solid-shell API achieves significantly faster convergence compared to Abaqus C3D8 and C3D8i elements.

Explore the gallery for an in-depth analysis of the results.

Check gallery below for the MRESS-API post-processed results on our GUI

Check gallery below for an Aircraft wing (Skin + C-Spar) with a tip loading example fully modeled with the MRESS-API

Results generated using the Shell MRESS API integrated into a custom solver.

Results generated using the Shell MRESS API integrated into a custom solver.

Constituents of the API package

Stiffness Matrix

Stiffness matrix for the MRESS solid-shell element. Required for linear and nonlinear analysis.

Geometric Stiffness Matrix

Geometric (Initial Stresses) Stiffness matrix for the MRESS element. It is required for nonlinear analysis with implicit time integration scheme.

Internal Forces

Internal Force Vector for the MRESS solid-shell element. Critical for nonlinear analysis with implicit time integration schemes.

Strain Tensor

Calculates the deformation tensor at the Gauss Points (GP) of the MRESS solid-shell element.

Rotation of local axes at the Gauss Points. Important for nonlinear co-rotational analysis, e.g. rotation of planar plastic anisotropic axes, rotation of composites ply axes at the GPs.

Axes Rotation at the GPs

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• Simulations from the input file and from the GUI

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• Linear Elastic template in C++

• Integration with the GUI for Linear Elastic Analysis

• GUI post-processing for Linear Elastic Analysis

• API Documentation & Installation

• API Support

• Free API updates

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• Simulations from the input file and from the GUI

• API Class

• Linear Elastic template in C++

• GUI included for pre- and post-processing

• Integration with the GUI for:

  • Linear Elastic Analysis

  • Buckling Analysis

  • Composite Materials

  • the Arc-Length method

  • Implicit Non-Linear Analysis

  • Multi-Point Constraints (MPC)

• Documentation & Installation

• API and GUI Support

• Free Training

• Free API and GUI updates

This API is developed and validated as part of MECHINMOTION's finite element research and engineering tools.