LAUSR

Abstract Vertical cylinders are widely used as supporting structures in ocean engineering applications. Shock waves due to underwater explosives (UNDEX) can cause serious damage to offshore structures, which has attracted the interest of many researchers. The propagation characteristics of shock waves produced by UNDEX across a cylinder are a complex physical phenomenon that involves fluid-structure dynamic interactions. For the shock wave produced by UNDEX, the total pressure on a cylinder consists of three parts, including the incident shock wave pressure, scattered wave pressure and radiation pressure due to the motion of the cylinder. This paper develops an improved method for obtaining the transient response of a vertical circular cylinder subjected to UNDEX. First, an empirical formula of the shock wave pressure for far-field UNDEX is adopted as the incident shock wave. Based on the continued fraction (CF) expansion of the frequency-domain dynamic stiffness coefficient, an accurate model in the time domain for solving the scattered wave pressures on a cylinder is further developed. Then, the added mass model is used to replace the fluid-structure interaction caused by radiation wave. Finally, the vibration equation of a Euler-Bernoulli beam is utilized to evaluate the transient response of the cylinder subjected to UNDEX.