ConFEM2D - a finite element program specialized in calculation of 2D reinforced concrete structures

ConFEM2D mainly focuses on the nonlinear behavior of 2D reinforced concrete structures. With the problem of determining the ultimate strength of a structure, ConFEM2D gives reliable result compared to other commercial FE softwares like Ansys, Atena. Its concrete material types uses the material library of the ConFem software written by prof. Ulrich Haussler-Combe, while its reinforcement material types are implemented based on elastoplastic Mises behavior. User can choice solver using a iterative method among three following methods : Newton-Raphson, BFGS and Arc-length. The input finite element mesh is prepared by means of a external mesh generator Gmsh4.0.

It is based on:

ConFem (U Haussler-Combe, PYTHON 2.7)
STAP (KJ Bathe, FORTRAN IV)

It includes:

Basic element types
- Truss
- Plate (tri, quad)
- Shell (tri, quad)
- Slab (generalized)
- Spring (linear, nonlinear)
Advanced element types
- Multi-layers shell (tri, quad)
- Bond element (between concrete and reinforcements)
Multiple material types
- Linear elastic behavior
- Elastic behavior with limited strength (used for modeling cracked concrete)
- Isodamage behavior for progressive reducing stiffness after concrete's crack initializing
- Simplified elastoplastic behavior for modeling of slab element
- Mises's elastoplastic behavior for modeling of reinforcement
- Nonlinear bond
Multiple solver choices for nonlinear problem:
- Newton-Raphson method (as default)
- Quasi-Newton BFGS method
- Arc length method

The figure below shows an example:

It works with:

Gmsh4.0 as finite element mesh generator.
or pygmsh as Python interface for Gmsh

The documentation is available here in PDF format. (not completed yet)

Requirements

Python == 2.7
numpy >= 1.14
scipy >= 1.1.0
matplotlib >= 2.2
scikit-umfpack >= 0.3.2
pywin32 >= 224
wheel >= 0.32

ming91915 / ConFEM2D