Accession Number:

AD0905201

Title:

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

Descriptive Note:

Final technical rept. 14 Apr 1969-30 Oct 1971

Corporate Author:

SOUTHWEST RESEARCH INST SAN ANTONIO TX

Report Date:

1972-09-01

Pagination or Media Count:

370.0

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 designanalysis program for structural application use and the program was used to generate bonded joint design allowable curves.

Subject Categories:

  • Couplers, Fasteners and Joints

Distribution Statement:

APPROVED FOR PUBLIC RELEASE