Development of an Understanding of the Fatigue Phenomena of Bonded and Bolted Joints in Advanced Filamentary Composite Materials. Volume III. Fatigue Analysis and Fatigue Mode Studies

摘要

The report presents the results of the empirical program undertaken to increase the basic understanding of the fatigue phenomena of advanced composites joints. Four basic design concepts were evaluated and include both bonded and mechanically fastened joints. A broad spectrum of joint geometry variations and loading conditions are included to identify the significant parameters affecting the fatigue endurance of composite joints. Test data and analyses are included for constant amplitude testing and program fatigue loading. Realistic spectrum and block spectrum data are evaluated using Miners Cumulative Damage Theory. In conjuction with other analyses and evaluations, failure mode studies were conducted on the fracture surface of failed specimens. Scanning electron microscope (SEM) photomicrographs were used for this failure study. (Author)