SEDL / STP / STP907-EB / STP19987S

Fatigue Damage in Notched Pultruded Composite Rods

Mallick, PK
Associate professor, professor, and student, University of Michigan-Dearborn, Dearborn, MI

Little, RE
Associate professor, professor, and student, University of Michigan-Dearborn, Dearborn, MI

Thomas, J
Associate professor, professor, and student, University of Michigan-Dearborn, Dearborn, MI

Pages: 13    Published: Jan 1986

Download this paper for $25 PDF (232K)          View License Agreement
Abstract

The primary damage mode in a notched pultruded composite rod in rotating bending fatigue was found to be fiber-matrix debonding which originated at the notch root and extended along the length of the specimen. At stress amplitudes equal to or greater than 35% of the tensile strength of the material, debonding was followed by tensile rupture of the fibers at or near the notch, resulting in catastrophic failures of the specimens. At lower stress amplitudes, the slow growth in debonding resulted in a gradual increase in the dynamic deflection of the specimen. The static flexural stiffness ratio of a fatigue-damaged specimen to that of an undamaged specimen was found to be a reasonable measure of damage due to fiber-matrix debonding.