The Development of Nonlinear Analysis Methods for Bonded Joints in Advanced Filamentary Composite Structures

Abstract

Development of analysis methods for orthotropic adherend bonded lap joints which account for material nonlinearities at room temperature is presented. The use of these methods in predicting mechanical behavior, ultimate loads, and failure modes is discussed. In order to accomplish this, new analytical procedures were developed and successfully checked with discrete element techniques for single, double, and step lap adhesively bonded attachment configurations. Experimental verification of these nonlinear analyses was accomplished by the fabrication and evaluation of a variety of simple joint specimens under static monotonically increasing load. Failure loads and modes were used as the primary substantiation characteristics but the mechanical behavior of a small number of these simple joint specimens was observed at intermediate loadings and found to compare favorably with the analytically predicted behavior. Larger, more complex bonded joints were designed, fabricated, and evaluated under static monotonically increasing loads at room temperature utilizing these methods. Ultimate load, failure mode, and detailed strain behavior at any intermediate load were accurately predicted with the new analyses, as substantiated by experimental observations. These techniques were put into a computerized design/analysis program for structural application use and the program was used to generate bonded joint design allowable curves.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1972
Accession Number
AD0905201

Entities

People

  • G. C. Grimes
  • G. E. Commerford
  • G. K. Wolfe
  • L. F. Greimann
  • T. Wah
  • W. R. Blackstone

Organizations

  • Southwest Research Institute

Tags

Communities of Interest

  • Air Platforms
  • Cyber
  • Sensors

DTIC Thesaurus Topics

  • Aircrafts
  • Composite Material Fabrication
  • Composite Materials
  • Laminates
  • Materials
  • Materials Laboratories
  • Materials Processing
  • Materials Science
  • Materials Testing
  • Measurement
  • Mechanical Working
  • Mechanics
  • Modulus Of Elasticity
  • Stress Strain Relations
  • Tensile Strength
  • Test And Evaluation
  • Three Dimensional

Readers

  • Software Engineering
  • Structural Health Monitoring of Composite Structures.