A UNIFIED APPROACH FOR MODELING INELASTIC BEHAVIOR OF STRUCTURAL METALS UNDER COMPLEX CYCLIC LOADINGS

This report develops a general procedure for modeling the inelastic stress-strain response of structural metals subjected to complex irregular cyclic loadings. The model is ideally suited for programming on a digital computer and uses "cyclic" material parameters (or properties) determined from simple constant strain amplitude cyclic tests. Four model formulations which include three degrees of simplification in the model are proposed and their appropriate applications are indicated. In its most complete formulation, the model is capable of simulating all the important observed phenomena of a wide range of structural metals, including hotworked and coldworked steels and aircraft aluminums. These phenomena include "memory" of prior history, cyclic hardening, cyclic softening, cyclic relaxation, cyclic creep, and the observed deviation from the Masing behavior. A major contribution of this report is in the development of a unified characterization of these phenomena. The model and the "cyclic" material parameters developed provide the necessary base for formulating a general constitutive equation in the multiaxial state of stress. Such constitutive equations are directly adoptable in the finite element codes of nonlinear structural analysis programs. The model is also useful in realistic shakedown analysis of structures and fatigue analysis of complex load histories.

• Corporate Authors:

  Army Construction Engineering Research Laboratory

  P.O. Box 4005
  Champaign, IL  United States  61820
• Authors:
  • Jhansale, H R
• Publication Date: 1977-5

Media Info

• Features: Figures; References; Tables;
• Pagination: 40 p.

Subject/Index Terms

• TRT Terms: Aluminum; Cold working; Concrete hardening; Creep; Cyclic tests; Deformation curve; Digital computers; Fatigue (Mechanics); Hardness; Inelastic stress; Mathematical models; Mechanical relaxation; Memory; Metal heating; Metals; Repeated loads; Softening point; Steel
• Uncontrolled Terms: Inelastic action; Models
• Old TRIS Terms: Cyclic creep; Hot working
• Subject Areas: Bridges and other structures; Highways;

Filing Info

• Accession Number: 00163556
• Record Type: Publication
• Report/Paper Numbers: Tech Report M-214 Final Rpt.
• Files: TRIS
• Created Date: Nov 9 1977 12:00AM