Accession Number:

AD0711399

Title:

APPROXIMATE THREE-DIMENSIONAL STRESS SOLUTIONS FOR SOME LAMINATED PLACE PROBLEMS USING A HIGHER ORDER EQUILIBRIUM FINITE ELEMENT MODEL. PART I. PRELIMINARY INVESTIGATIONS.

Descriptive Note:

Technical summary rept. 1 Nov 69-31 May 70,

Corporate Author:

BATTELLE MEMORIAL INST COLUMBUS OHIO

Personal Author(s):

• Rybicki,Edmund F.

Report Date:

1970-08-01

Pagination or Media Count:

51.0

Abstract:

A preliminary investigation of a method for obtaining approximate three-dimensional stress solutions for some laminated plates is presented. The laminates are three-ply symmetric lay-ups. The material of each lamina is orthotropic and homogeneous. The stress-strain relations are linear and the behavior is the same in tension as compression. Displacement and stress boundary conditions are considered. The method of analysis utilizes the complementary energy formulation and a higher order three-dimensional finite element representation for the Maxwell stress functions. Equilibrium within each material and between distinct materials is satisfied exactly. Stress boundary conditions and stress-strain relations are satisfied exactly. Compatibility and displacement boundary conditions are satisfied approximately. One element per lamina is used. This representation yields from 216 to 600 unknowns depending on the boundary conditions. A computer program based on the method of analysis was developed. Results for selected laminates are presented and discussed. Author

Descriptors:

• (*COMPOSITE MATERIALS
• STRUCTURAL PROPERTIES)
• (*LAMINATES
• STRESSES)
• MATHEMATICAL MODELS
• PARTIAL DIFFERENTIAL EQUATIONS
• TENSOR ANALYSIS
• STRAIN(MECHANICS)
• ELASTIC PROPERTIES

Subject Categories:

• Laminates and Composite Materials
• Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE