Example finite element codes
   These files illustrate key concepts in finite element analysis.  They are coded as worksheets for the
  MAPLE program, partly to make them as transparent as possible, and partly to enable you to use
  the sophisticated linear algebra capabilities in MAPLE to examine properties of stiffness matrices, etc.

 MAPLE is available on Brown's application server.  If you are not familiar with it here is an elementary tutorial

To run the programs, click on the link and save the file with a .mws extension (stands for maple worksheet).  Then
start MAPLE and open the file.

All the input files are set up for Maple 6.  For Maple 5 you need to add a comma after each number...

To run the codes that require an input file you will need to edit the MAPLE file to specify the file name.

1. Simple 1D finite element code (FEM1Dstatic.mws)discussed in the lecture notes
2. General 2D and 3D static linear elastic FEM code (FEMlinelast.mws) with a sample input file  (demo1.txt) (solves the problem described in lecture notes: two triangular plane elements under uniaxial tension)
      A few additional sample input files are: 
                      demo2.txt   Illustrates two 8 noded plane strain elements under tension 
                      demo3.txt   Illustrates tetrahedral elements under tension
                      demo4.txt   Sets up a problem with ill posed boundary conditions 
                                        (get MAPLE to calculate eigenvalues & eigenvectors of the stiffness matrix!)
                       

3. 1D dynamic finite element code (FEM1dnew.mws) with Newmark time integration discussed in the lecture notes. Check out the cool animations!!
4. 1D dynamic finite element code with modal time integration discussed in the lecture notes

5. 2D/3D elastodynamic FEM (FEMdynamic.mws) code with Newmark time integration, with a sample input file (tstdynamic.txt)  (calculates and animates motion for a 2D beam subjected to a transverse load on one end)
6. 2D/3D elastodynamic FEM code with modal dynamics, with a sample input file (calculates mode shapes and natural frequencies for a 2D beam)

7. 2D/3D hypoelastic FEM (FEMhypo.mws) illustrates Newton-Raphson iteration to solve virtual work equation with a nonlinear stress-strain law, with a sample input file (sets up a simple 1 element problem in uniaxial tension)
8. 2D/3D hyperelastic FEM (FEMhyper.mws) illustrates solution of nonlinear elasticity problem with finite deformations, with a sample input file (simple 1 element problem in uniaxial tension)
9. 2D/3D small strain plasticity FEM (FEMplastic.mws) illustrates solution of problems with nonlinear history dependent materials, with a sample input file (simple 1 element problem in uniaxial tension)