Nonlinear Analysis and Experimental Behavior of a Curved Unitized Stitched Panel

• Published in: Journal of aircraft 2015-03, Vol.52 (2), p.628-637
• Main Authors: Gould, Kevin, Lovejoy, Andrew E, Jegley, Dawn, Neal, Albert L, Linton, Kim A, Bergan, Andrew C, Bakuckas, John G
• Format: Article
• Language: English
• Subjects: Aerodynamics; Aircraft; Aircraft components; Aircraft industry; Airframes; Aluminum; Aviation; Axial stress; Combined loading; Company structure; Correlation analysis; Curved panels; Damage; Design engineering; Fuselages; Internal pressure; Load; Loads (forces); Nonlinear analysis; Nonlinearity; Panels; Research facilities; Wings (aircraft)
• ISSN: 0021-8669; 1533-3868
• DOI: 10.2514/1.C032808

The pultruded rod stitched efficient unitized structure concept, developed by The Boeing Company, has been extensively studied as part of NASA’s environmentally responsible aviation project. The pultruded rod stitched efficient unitized structure concept provides a lightweight alternative to aluminum or traditional composite design concepts and is applicable to traditional-shaped fuselage barrels and wings, as well as advanced configurations such as a hybrid wing–body or truss-braced wings. Therefore, NASA, the Federal Aviation Administration, and The Boeing Company partnered in an effort to assess the performance and damage arrestments capabilities of the pultruded rod stitched efficient unitized structure concept by testing a full-scale curved panel in the Federal Aviation Administration full-scale aircraft structural test evaluation and research facility. Testing was conducted in this facility by subjecting the panel to axial tension loads applied to the ends of the panel, internal pressure, and combined axial tension and internal pressure loadings. Additionally, reactive hoop loads were applied to the skin and frames of the panel along its edges. The panel successfully supported the required design loads in the pristine condition and with a severed stiffener. The panel also demonstrated that the pultruded rod stitched efficient unitized structure concept could arrest the progression of damage, including crack arrestment and crack turning. This paper presents the nonlinear posttest analysis and correlation with test results for the curved pultruded rod stitched efficient unitized structure panel. It is shown that nonlinear analysis can accurately calculate the behavior of this panel under tension, pressure, and combined loading conditions.