Fracture and Fatigue Strength Evaluation of Multiple Site Damaged Aircraft Fuselages - Curved Panel Testing and Analysis.

摘要

As the fleet of commercial passenger aircraft is utilized beyond their design Lives, flaws have developed at the rivet holes of fuselage lap joints on some aircraft which can grow and link up into cracks of significant length. Understanding predicting, and controlling this crack growth and the ensuing linkup requires analysis and evaluation of the structural parameters in concert with confirmation by testing representative models of the fuselage. A dedicated test facility has been designed, built and tested for this purpose. Seven full-sized curved fuselage panels have been built and tested. This report describes the design rationale for the facility, the details of its construction and performance and the design and testing of compatible panels which simulate fuselage structural details. Data on basic material properties of interest to the aging aircraft issue have been compiled from existing Literature and from R-curve testing and rivet stiffness testing performed as part of the effort. Analytic techniques have been developed to evaluate stress distributions and to estimate elastic stress intensity factors for flat and curved test panels. A flat test panel has been designed that demonstrates hoop stress equivalence to the curved fuselage. A 3-D FE mesh of a riveted lap joint is also presented. Aging aircraft, Multiple site damage, Fuselage fracture and Fatigue.