**RSICC CODE PACKAGE PSR-458**

**1. NAME AND TITLE**

NONSAP-C: Code System for Analysis of 3-D Reinforced Concrete Structures.

**2. CONTRIBUTORS**

Los Alamos National Laboratory, Los Alamos, New Mexico through the Energy Science and Technology Software Center, Oak Ridge, Tennessee.

**3. CODING LANGUAGE AND COMPUTER**

FORTRAN IV (CDC FORTRAN Extended); CDC 7600 (P00458C760000).

**4. NATURE OF PROBLEM SOLVED**

NONSAP-C is a finite element program for determining the static and dynamic response of three-dimensional reinforced concrete structures. Long-term, or creep, behavior of concrete structures can also be analyzed. Nonlinear constitutive relations for concrete under short-term loads are incorporated in two time-independent models, a variable-modulus approach with orthotropic behavior induced in the concrete due to the development of different tangent moduli in different directions and an elastic-plastic model in which the concrete is assumed to be a continuous, isotropic, and linearly elastic-plastic strain-hardening-fracture material. A viscoelastic constitutive model for long-term thermal creep of concrete is included. Three-dimensional finite elements available in NONSAP-C include a truss element, a multinode tendon element for prestressed and post tensioned concrete structures, an elastic-plastic membrane element to represent the behavior of cavity liners, and a general isoparametric element with a variable number of nodes for analysis of solids and thick shells.

**5. METHOD OF SOLUTION**

NONSAP-C uses the isoparametric finite element formulation. Dynamic problems are solved by integration of the equations of motion in the time domain using either the Wilson-Theta or Newmark-Beta integration algorithms. Equilibrium iteration or stiffness reformulation schemes can be applied in solving the nonlinear discretized equations.

**6. RESTRICTIONS OR LIMITATIONS**

An out-of-core equation solver for large systems of linear equations allows practically unlimited problem size. The truss and tendon elements are assumed to have constant area. The tendon element cannot be used in geometrically nonlinear analyses.

**7. TYPICAL RUNNING TIME**

A problem with 10,569 equations and a half bandwidth of 532 required 2750 CPU seconds on a CDC7600. The longest running sample problem requires about 670 CPU seconds on a CDC7600.

**8. COMPUTER HARDWARE REQUIREMENTS**

Approximately 115K (octal) words of small core memory and 345K (octal) words of large core memory and 19 disk files are used by the program on a CDC7600.

**9. COMPUTER SOFTWARE REQUIREMENTS**

The program required a FORTRAN IV (CDC Fortran Extended) compiler and either LTSS (CDC7600) or SCOPE 2.1.5 (CDC7600) operating systems.

**10. REFERENCES**

C. A. Anderson, P. D. Smith, and L. M. Carruthers, "NONSAP-C: A Nonlinear Stress Analysis Program for Concrete Containments Under Static, Dynamic, and Long-Term Loadings," NUREG/CR-0416, LA-7496-MS Rev. 1 (January 1982).

**11. CONTENTS OF CODE PACKAGE**

Included in the package are the referenced document and one 3.5" diskette which includes Fortran source and test case input and output written in DOS format.

**12. DATE OF ABSTRACT**

November 1999.

** KEYWORDS:** NUCLEAR SAFETY; CONTAINMENT