CAL

Educational program developed to support teaching and learning of structural analysis concepts and techniques. Originally developed at the University of California, Berkeley by Professor Edward L. Wilson in 1976. The program has been used worldwide at over 100 universities.



History and Background
The basic purpose of the CAL language is to bridge the gap between traditional methods of teaching structural analysis and the use of automated structural analysis programs. As a result of using CAL-91, it is hoped that engineers will understand the theory and approximations which are used in modern structural analysis programs. CAL-91 is designed to interpret a sequence of commands which are supplied by the user. The commands can be given directly in an "interactive mode," or the program can read the commands from a "batch data file." The input has been redesigned so all commands, array names, and data are in free- field form. Commands for matrix analysis, direct stiffness structural analysis, and dynamic response analysis are possible. The program is written in standard FORTRAN 77 and will operate on small microcomputers or large mainframe computers. Printer plots of results can be produced.

CAL-91 is used to perform linear dynamic analysis of small structural systems. It is possible to solve the following types of dynamic problems:


 * 1) Evaluation of free-vibration mode shapes and frequencies.
 * 2) Automatic generation of Ritz vectors to be used in mode superposition analysis or response spectra analysis.
 * 3) Mode superposition analysis due to arbitrary loading.
 * 4) Response spectra analysis due to earthquake loading.
 * 5) Step- by-step analysis of structural systems with arbitrary viscous damping.

Basic Commands
ZERO - create a zero array

LOAD - loads an array from keyboard or input file

Matrix Operations
SOLVE - solve a set of equations

DUPSM - duplication of submatrix

Direct Stiffness
SLOPE - formation of 4x4 stiffness matrix

LOADI - load integer array

ADDK - add member stiffness to total stiffness

Dynamic Analysis
SQREL - square of each term in a matrix

JACOBI - eigensolution with full mass matrix