1. GENERAL. Currently a large number of structural mechanics programs are
available, most of which utilize finite element methods, finite difference
methods or a combination of the two.
a. Finite Element Computer Programs. Four widely used finite
element computer programs that have provisions for both static and dynamic
structural behavior are listed in Table 34. Their applicability to blast
resistant design is indicated by x's and dashes. Additional features of
these programs, ADINA, ANSYS, NASTRAN, and STARDYNE are described in their
b. Additional Computer Programs. There are eight additional
programs now available to the Navy, which are not as well known as the four
described above. These programs offer unique capabilities for blast
resistant design and were developed specifically to analyze structures
encountered in this area. A brief description of each of these eight
programs (DYNFA, OVER, BLAST, CEL SAPS5, BARCS, INSLAB, SINGER, and SDOOR)
is presented in the next several paragraphs. Most of these programs were
written in FORTRAN IV for the Control Data System, CDC 6600 computer and
they are available to the Navy PWC/Ds, EFDs and NAVFACENGCOM. The programs
are stored in the NAVFACENGCOM Library and the user can operate the
programs via a time-share or batch terminal by addressing the Control Data
Corporation CYBERNET Computer System. Additional information about these
programs can be obtained from the Civil Engineering Laboratory, Naval
Construction and Battalion Center in Port Hueneme, California.
(1) DYNFA - NONLINEAR ANALYSIS OF FRAME STRUCTURES SUBJECTED TO
(a) DYNFA was designed specifically to determine the response
of frame structures to time-dependent blast loadings. This program
implements a method of analysis which couples a lumped parameter
representation of the structure with numerical integration procedure to
obtain a solution.
(b) In addition to metal plasticity and other non-linear
effects which are accounted for in the program, the P and beam-column
effects are also considered. A static analysis routine is included and when
utilized, the static nodal displacements and element loads are used as the
initial conditions for the dynamic analysis.
(c) The results of the dynamic analysis consist of the
deformations of the structure expressed in terms of the nodal displacements
and rotations, the axial loads, bending moments and shears in each of the
elements, and the plastic deformations expressed in terms of ductility
ratios of the elements.
(d) The program is written in FORTRAN IV for execution on the
CDC 6600 computer using the Extended (FE) FORTRAN computer. A central
memory field length of 170,000 words (octal) is required for execution of
the program on this computer.