RSICC CODE PACKAGE PSR-388

1. NAME AND TITLE

CARES 1.0 & 1.2: Computer Analysis for Rapid Evaluation of Structures. PSR-538/P-CARES is updated version.

2. CONTRIBUTORS

Brookhaven National Laboratory, Upton, New York.

Constantino, Miller and Associates, Monsey, NY through the Energy Science and Technology Software Center, Oak Ridge, Tennessee.

3. CODING LANGUAGE AND COMPUTER

CARES Version 1.2: FORTRAN; SUN SPARC (P00388SUN0500).

CARES Version 1.0: FORTRAN; IBM PC (P00388IBMPC00).

4. NATURE OF PROBLEM SOLVED

CARES1.2, Computer Analysis for Rapid Evaluation of Structures, was developed for NRC staff use to determine the validity and accuracy of the analysis methods used by various utilities for structural safety evaluations of nuclear power plants. CARES1.2 is organized in a modular format with the basic modules of the system performing static, seismic, and nonlinear analysis. In this release, only the seismic module is implemented. This module defines the design seismic criteria at a given site, evaluates the free-field motion, and computes the structural response and floor response spectra including soil-structure interaction. The eight options in CARES1.2 currently are: a general manager for the seismic module, deconvolution analysis, structural data preparation for soil-structure interaction (SSI) analysis, input motion preparation for SSI analysis, SSI analysis, earthquake simulations/data, PSD (Power Spectral Density) related acceleration time history/spectra analysis, and plot generation.

5. METHOD OF SOLUTION

The seismic module works in the frequency domain. Earthquake motion simulation is based on the fundamental property that any periodic function can be expanded in a series of sinusoidal waves. The computer uses a random number generator to produce strings of phase angles with uniform distribution in the 0-2 pi range. Then, a linear correction procedure due to Scanlon and Sacks is employed to derive an adjusted array of amplitudes. The acceleration ensemble is subsequently modified by a deterministic intensity function composed of three segments: an initial buildup, a stationary duration, and exponential steady decay. A parabolic correction procedure outlined by Jennings and Housner is applied to the acceleration ensemble to bring the end velocity of the ground motion to zero. The soil-structure system is represented by a three-dimensional lumped parameter type model. The structural model is built up from three-dimensional shear beam elements as well as three-dimensional spring type elements.

6. RESTRICTIONS OR LIMITATIONS

The superstructure model is restricted to about 20 degrees-of-freedom. The foundation configurations are primarily restricted to uniform half spaces. The free-field analysis is restricted to one-dimensional shear waves.

7. TYPICAL RUNNING TIME

Running times vary w/problem. Pentium II (266 Mhz) test computer (DOS version) took less that 1 sec between iterations.

8. COMPUTER HARDWARE REQUIREMENTS

CARES 1.2: SUN SPARC 60 Workstation.

CARES 1.0 : IBM PC w/640 kbytes of RAM, 10 Mbytes free drive space, one - 3.5" floppy disk drive, math coprocessor, Hercules or EGA graphics monitor.

9. COMPUTER SOFTWARE REQUIREMENTS

CARES 1.2: SunOS v. 5.6.

CARES 1.0: MS-DOS 3.1 or later.

10. REFERENCES

a. Documentation for the SUN version 1.2:

C. J. Costantino, C. A. Miller, E. Heymsfield and A. Yang, "CARES: Computer Analysis for Rapid Evaluation of Structures Version 1.2" (September 1995).

b. Documentation for the PC version 1.0:

NESC Note 91-54, "CARES" NUREG/CR-5588 Vol. 3 Errata.

J. Zu, A. J. Philippacopoulas, C. A. Miller and C. J. Costantino, "CARES (Computer Analysis for Rapid Evaluation of Structures) Version 1.0, Seismic Module Theoretical Manual," NUREG/CR-5588 (BNL-NUREG-52241), Vol.1 (July 1990).

J. Xu, A. J. Philippacopoulas, C. A. Miller, and C. J. Costantino, "CARES (Computer Analysis for Rapid Evaluation of Structures) Version 1.0, Seismic Module User's Manual," NUREG/CR-5588 (BNL-NUREG-52241), Vol. 2 (July 1990).

J. Xu, A. J. Philippacopoulas, C. A. Miller, and C. J. Costantino, "CARES (Computer Analysis for Rapid Evaluation of Structures) Version 1.0, Seismic Module Sample Problems," NUREG/CR-5588 (BNL-NUREG-52241), Vol. 3 (July 1990).

11. CONTENTS OF CODE PACKAGE

Included are reference documents and one 3.5" DOS diskette, CARES 1.2 media which contains source code (CARES 1.0 media includes executables only).

12. DATE OF ABSTRACT

February 1999.

KEYWORD: SEISMIC