Nonlinear dynamics of locally pulse loaded square Föppl-von Kármán thin plates
File(s)MANUSCRIPT_IJMS_FVK_Revised.pdf (2.26 MB)
Accepted version
Author(s)
Mehreganian, N
Fallah, AS
Louca, LA
Type
Journal Article
Abstract
Modern armour graded thin steel plates benefit from significant elastic strength with high elastic energy storage capacity, which contributes to dissipation of total impulse from extensive blast loads within the bounds of the elastic region. Higher elastic energy storage capability mitigates the probability of catastrophic damage and ensuing large deformations compared to the conventional graded metallic panels. While blast assessment of such structures is important to design and application of protective systems, limited studies are available on their response to localised blasts. The present paper aims at deducing, from the minimization of Föppl-von Kármán (FVK) energy functional, the dynamic response of localised blast loaded thin elastic square plates undergoing large deformations. The presumed blast load function is a multiplicative decomposition of a prescribed continuous piecewise smooth spatial function and an arbitrary temporal function which may assume various shapes (e.g. rectangular, linear, sinusoidal, exponential). A kinematically admissible displacement field and the associated stress tensor were considered as a truncated cosine series with multiple Degrees-of-Freedom (DoF's). From the prescribed displacement field, having simply supported boundary conditions, useful expressions for stress tensor components were delineated corresponding to a unique mode and a series of differential equations were derived. The explicit solutions were sought using the Poincaré-Lindstedt perturbation method. The closed form solutions of each mode were corroborated with the numerical FE models and showed convergence when the first few modes were considered. The influence of higher modes, however, on the peak deformation was negligible and the solution with 3 DOF's conveniently estimated the blast response to a satisfactory precision.
Date Issued
2019-11-01
Online Publication Date
2020-09-11T06:00:18Z
Date Acceptance
2019-09-10
ISSN
0020-7403
Publisher
Elsevier BV
Journal / Book Title
International Journal of Mechanical Sciences
Volume
163
Copyright Statement
© 2019 Elsevier Ltd. All rights reserved. This manuscript is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Licence http://creativecommons.org/licenses/by-nc-nd/4.0/.
Subjects
Mechanical Engineering & Transports
0910 Manufacturing Engineering
0905 Civil Engineering
0913 Mechanical Engineering
Publication Status
Published
Article Number
105157
Date Publish Online
2019-09-11