Collapse behavior of carbon-fiber epoxy cylinders subjected to long-term seawater exposure at seafloor depth pressures. (July 2022)

• Record Type: Journal Article
• Authors: Chu, Tyler; Fontaine, Dillon; LeBlanc, James; Shukla, Arun
• Is Part Of: Marine structures. Volume 84(2022)
• Publication Date: 2022-07
• Subjects: Naval architecture -- Periodicals; Offshore structures -- Periodicals; Architecture navale -- Périodiques; Structures offshore -- Périodiques; Naval architecture; Offshore structures; Periodicals; 620.4162
• DOI: 10.1016/j.marstruc.2022.103219
• Languages: English
• ISSNs: 0951-8339

Abstract

Abstract: The effects of simulated long-term exposure of carbon-fiber/epoxy (CFE) hollow cylinders to high pressure seawater were investigated experimentally. Utilizing accelerated life testing informed by the Arrhenius methodology, specimens were aged in 41.1 MPa (6000 psi) pressurized 3.5% saline water for durations representing 0, 193.5, and 516 days of service at 3 °C. Hydrostatically and explosively initiated implosion experiments were performed in a large pressure vessel simulating free field conditions. The events were recorded with high-speed stereo photography and analyzed using 3D digital image correlation (DIC) techniques. High frequency response pressure transducers captured a detailed pressure history of each event. Analysis of the collapse phenomena suggests that exposure to the abyssal environment at the timescales investigated had negligible effects on the response of CFE structures subjected to dynamic instability. Highlights: Hollow carbon fiber epoxy tubes underwent accelerated aging in high pressure saline at elevated temperatures. The tubes were removed from the aging pressure at predetermined times and had their ends waterproofed and sealed. The tubes were hydrostatically pressurized or explosively loaded to induce implosion. Results were compared to previous publications done on similar tubes aged at atmospheric pressure. The tubes aged at high pressures suffered minimal degradation compared to those aged at atmospheric pressure.