Experimental investigation on edge impact damage and Compression-After-Impact (CAI) behavior of stiffened composite panels. (15th March 2016)

• Record Type: Journal Article
• Authors: Li, N.; Chen, P.H.
• Is Part Of: Composite structures. Volume 138(2016)
• Page Start: 134
• Page End: 150
• Publication Date: 2016-03-15
• Subjects: Stiffened composite panels -- Edge impact -- Compression failure mechanism -- Damage tolerance -- Tests; Composite construction -- Periodicals; Composites -- Périodiques; 624.18
• DOI: 10.1016/j.compstruct.2015.11.060
• Languages: English
• ISSNs: 0263-8223

Abstract

Abstract: The purpose of this paper was to investigate the effect of low velocity edge impact damage on the damage tolerance of wing relevant composite panels stiffened with both T-shaped and I-shaped stiffeners under uniaxial compression load. Six stiffened composite panel configurations, including four specimens for each configuration, were manufactured and tested. Before Compression-After-Impact (CAI) tests, the key dimensions of specimens were measured and a vertical drop-weight testing device was used to impact on critical locations such as the skin and the free edge of a stiffener. Different damage types and shapes were discovered from different locations of impact after careful inspection by visual and ultrasonic C-scan. The experimental results reveal the compression failure mechanism that local buckling, subsequent damage propagation and final fracture of the edge impacted stiffener are triggers of the final failure of a stiffened composite panel, which as well determine the ultimate load carrying capacity. In addition, under identical edge impact levels, the damage tolerance behavior of T-stiffened composite panel is distinctly superior to that of I-stiffened composite panel, which results in more cautious design regarding edge impact damage tolerance of the panel stiffened with I-stiffeners.