Computation of Rayleigh damping coefficient of a rectangular submerged floating tunnel (SFT)

• Main Authors: Md. Hafizur Rahman, Chhavi Gupta
• Format: Article
• Language: English
• Published: Springer 2020-04-01
• Series: SN Applied Sciences
• Subjects: Buoyant; Slenderness; Rayleigh damping coefficients; Mode’s motion
• Online Access: https://doi.org/10.1007/s42452-020-2629-z

Abstract The dynamic behaviors of the submerged floating tunnel, a buoyant structure of high slenderness, are a matter of concern since it is surrounded by the huge hazardous effects called hydrodynamic, seismic and functional action. Modal analysis and Rayleigh damping coefficients play a significant role in dynamic analysis, but it is not sufficiently simple to predict the reasonable damping coefficients named α and β. The present paper outlines the modal analysis and the calculation of Rayleigh damping coefficients that provide the natural frequencies, mode shapes, mode’s motion as well as coefficients α and β. To compute the Rayleigh damping coefficients, 2–10% damping to the critical damping has been assumed for this analytical study. For the analysis, an FEA-based software ANSYS is utilized successfully. It has been seen that the fundamental frequency and Rayleigh damping coefficients (α = 0.946 and β = 0.00022) of the SFT are reasonably high and it is under noticeable damping.