FEAST (Finite Element Analysis of Spliced Timber)

          FEAST is a finite element analysis program which was originally written and contains special elements for modeling spliced, vertically, mechanically-laminated wood members.  The version available here is the original bare-bones FORTRAN program written in 1987. It is bare bones in that in that it has no special preprocessor to assist in the input of information, nor does it have a post-processor to aid in data analyses.  A version of the program developed in the early 90's contains a preprocessor that allows for screen editing of program input.  The reason for not providing the later edition here is that there is no accompanying documentation to assist in its use.

          FEAST has unique capabilities.  It can analyze laminated assemblies in a way that today's extremely more powerful and user-friendly finite element programs can not.  FEAST was used extensively at UW-Madison to improve our understanding of spliced, vertically-laminated wood assemblies.  To this end, it laid the foundation for the development of ASABE Engineering Practice on mechanically-laminated posts.

Downloads

FOR

FEAST Fortran Source Code

EXE

FEAST Executable File

PDF

Theoretical and User's Manual for FEAST

PDF

MLBeam

          MLBeam (Multi-Layer Beam analysis) is the compliment to FEAST in that it is used to analyze horizontally, mechanically-laminated assemblies, whereas FEAST is used to model vertically, mechanically-laminated assemblies. MLBeam is somewhat of a spin-off of FEAST in that it was developed after FEAST, and uses many similar FORTRAN subroutines.

         MLBeam has been used at UW-Madison to study I-beams fabricated by nailing together three pieces of dimension lumber.  It has also been used to study the impact of adding face plates to laminated posts (see publications on horizontally-mechanically-laminated assemblies).  FEAST and MLBeam would be excellent tools for studying the effects of T- or L-bracing of truss web members to reduce buckling potential.

Downloads

FOR

MLBeam Fortran Source Code

EXE

MLBeam Executable File

PDF

User's Manual for MLBeam

PDF

DAFI (Diaphragm and Frame Interaction)

          DAFI is a computer program for calculating the distribution of horizontal loads among the individual post-frames and roof diaphragm sections of a building.  It can be used to analyze diaphragm action in buildings in which bay spacings vary, the stiffness of individual post-frames differ, endwalls are not assumed infinitely rigid, and/or the stiffness of individual diaphragms are not the same. DAFI can best be described as a specialized equation solver since it does little more than simultaneously solve the equations of equilibrium relating frame eave loads and deflections. There is a single equilibrium equation for each building frame (i.e., each frame is allowed a single displacement degree of freedom, that being a horizontal translation of the eave in a direction parallel to the frame).

          The original MS-DOS version of the program allows data to be input to the program directly from the keyboard or from an input data file.  A windows version that is much more user friendly is almost complete.  It allows data to be entered using a special screen editor.  The data can be saved to and later recalled from an input data file.  The on screen editor enables input of default loads and stiffness values which speeds data entry.

          The MS-DOS version of the program is a single executable file that can be run directly on most machines.  The Windows version of DAFI is being written by Benjamin D. Bohnhoff and will consist of several files conveniently zipped for downloading.            

Downloads

FOR

DAFI Fortran Source Code (Original MS-DOS Program)

EXE

DAFI Executable File (Original MS-DOS Program)

PDF

Article on DAFI that includes an example analysis

DAFI3 (Diaphragm and Frame Interaction - 3 Degrees of Freedom per Frame)

          DAFI3 is a computer program that is currently under development by Benjamin D. Bohnhoff. It will differ from DAFI in that each frame will be associated with three horizontal translational degrees of freedom: one parallel to the frame itself, and one parallel to each sidewall.  Required program input includes frame stiffness, roof/ceiling diaphragm stiffness values for each bay, sidewall stiffness, chord axial stiffness and eave loads.