FEAP

A Finite Element Analysis Program

FEAP is a general-purpose finite element analysis program designed for research and educational use. It includes options for 1D, 2D, and 3D meshes, linear and nonlinear solution algorithms, graphics options, and a comprehensive element library.

Contact feap@berkeley.edu for Cost & Distribution Looking for FEAPpv (Free Personal Version)?

Overview

Source code of the full program is available for compilation using Windows (Intel compiler), LINUX or UNIX operating systems, and Mac OS X based Apple systems (GNU and Intel compilers).

The program features constitutive models including linear and finite elasticity, viscoelasticity with damage, and elasto-plasticity. Element libraries include linear and nonlinear solids, thermal elements, frame (rod/beam) elements, plate/shell elements, torsion elements, winkler foundation elements, acoustic elements, coupled problem elements, and rigid body options with joint interactions.

Mesh Generation: The system may be used in conjunction with mesh generation programs that output nodal coordinates and element connection arrays. User functions may need to be written to input this data.

Version 8.7 Updates

Version 8.7 introduces major architectural updates, new multi-physics element families, an Isogeometric (IGA) overhaul, and numerous enhancements across the core program.

New Elements & IGA Overhaul

Multi-Physics & Core Elements
  • New Element Families: Added Poroelastic, Chemoelastic, and Piezoelectric n-D element families.
  • VEM & Fluids: Added support for 14-node hex VEM elements, non-convex VEM elements, and Masud fluid elements.
  • Classical FEAP: Added several small/finite-strain material additions.
Isogeometric Analysis (IGA)
  • Complete renumbering and renaming scheme applied to all IGA elements.
  • Introduced new IGA membrane and slope elements.
  • Reworked mesh macros to fully support new table, spline, mesh-interface, and DG/periodic inputs.
FE2 / RVE Enhancements
  • Added user RVE modules, random-variable array (RANDN) support, and traction boundary options.

Mesh Commands, Plotting & Build System

Mesh & Boundary Conditions
  • New TABLE and SPLINE input commands for tabular data and B-spline/NURBS 1-D infrastructure.
  • New INTErface mesh command for 2-D and 3-D.
  • TIE command extended to support single-node ties.
  • New Discontinuous Galerkin (DG) and periodic boundary condition inputs.
Plotting & Projections
  • New PLOT ZZHU command with Zienkiewicz-Zhu projection updates.
  • New AVERage command for plots/projections at material interfaces.
  • Added local-least-squares projection and linear projection on tetrahedrons.
Build & System Utilities
  • Revamped build system for Windows with pre-configured Visual Studio solutions (feap_sol.sln).
  • Implemented over 180 bug fixes, widespread Fortran format cleanups, and ISO C updates.

Manuals for FEAP (Ver 8.7)

June 2020 editions. Requires Acrobat Reader to view and print.

Resources & Interfaces

Test Problems & User Elements

Additional Elements (Ver 7.3 - 8.6):

MATLAB Interface

The MATLAB interface is a standard part of versions 8.1 and later, allowing output of residual, tangent, mass, or damping matrices.

Direct Link: A direct link permitting FEAP to be run directly from MATLAB is available from David Bindel's site.

Linear Equation Solver Interfaces

SuperLU Solver

Interface for the general sparse solver SuperLU. Tested in Linux and MAC OSX environments.

UMFPACK Solver

Interface for the general sparse solver UMFPACK (Pre-dates SuiteSparse).

Pardiso & SGI Solvers

WSMP Solvers

Interface for the Watson Sparse Matrix Package (IBM Research).

Community & Support

Interact with other users, ask questions, and contribute to the FEAP knowledge base.

Other FEAP Web Sites

  • Sanjay Govindjee
    Contains examples for user functions as well as a C interface for developing elements.
  • David Bindel
    A MATLAB interface to FEAP which permits simultaneous access to both programs.