Simplified Analytical Approach to Evaluate the Nonlinear Dynamics of Elastic Cylindrical Shells Under Lateral Blast Loads

Abstract

This paper presents an analytical solution to predict the nonlinear forced vibrations of elastic thin-walled cylindrical shells under suddenly applied loads. Interest in this problem is motivated by effects due to explosions on fluid-storage metal tanks. The model is based on the energy criterion due to Lagrange, in which the kinematic nonlinear relations are assumed using Donnell's simplified shell theory. Solution is achieved as a series summation in terms of trigonometric functions in the axial and circumferential directions, whereas the degrees of freedom depend on time. A blast load is assumed to represent effects due to explosions on the shell as timedependent pressures with a given circumferential distribution (a cosine square distribution in terms of the central angle). The procedure is validated by comparison with a nonlinear finite element model under the same load conditions. The influence of load level and shell geometry on the transient response is investigated by mean of parametric studies. Good accuracy is found in the results for the range of shells which are representative of horizontal, fuel storage tanks in the oil industry.

Simplified expressions for dynamic behavior of cylindrical shells uncoupled and coupled with liquids

“…Some of these studies comprise the direct solution of the equations of movement, whereas others are based on variational methods (energy based). Examples are given by the works of Sharma and Johns (1971), Chung (1981), Soedel (2005), Farshindianfar and Oliazadeh (2012), Chen et al (2013), Dai et al (2013), Sun et al (2013), Ataabadi et al (2014), Ameijeiras and Godoy (2016), and Qin et al (2017). These works admit different shell theories to simulate deformations, as well as different displacement assumptions, such as: beam modal functions, characteristic orthogonal polynomials, Chebyshev polynomials, or exact Fourier series solution.…”

A New Analytical Prediction for Energy Responses of Hemi-Cylindrical Shells to Explosive Blast Load

“…Hemi-cylindrical shell structures are used in many applications in ocean engineering, aerospace, composite materials and civil engineering [1][2][3][4][5][6]. For example, submarine, sea detector, aircraft brakes, ballistic components, gymnasiums, modern libraries, buried gas pipelines, and large span roofs are some of the distinct fields of applications [7][8][9][10]. In all these applications, the cylindrically curved panel structures can be subjected to different loading conditions.…”