Analytical and Finite Element Modelling of Circular Glare Plates under Indentation Loading and Unloading

In this paper, analytical expressions are derived and a finite element modelling procedure is proposed in order to predict the static load-indentation curves of circular GLARE fibre-metal laminates during loading and unloading by a hemispherical indentor. Analytical formulas have been recently published for the static indentation of circular GLARE plates which are now used during the loading stage. Here, considering that aluminum layers are in a state of membrane yield and employing energy balance during unloading, the unloading path is determined. Using this unloading path, an algebraic equation is derived and solved for calculating the permanent dent depth of the GLARE plate after the indentor's withdrawal. ANSYS software is used and a non-linear analysis is employed with geometric and material non-linearities for FEM calculations. The derived formulas and the proposed finite element modelling procedure are applied to GLARE 2-2/1-0.3 and to GLARE 3-3/2-0.4 circular plates. The analytical results are compared with corresponding FEM results and a good agreement is found. The analytically calculated permanent dent depth is within 6 % for the GLARE 2 plate, and within 7 % for the GLARE 3 plate, of the corresponding numerically calculated result. No other solution of this problem is known to the authors.

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Finite-Element Modelling of Multi-Planar Offshore Tubular Joints

Journal of Offshore Mechanics and Arctic Engineering ◽

10.1115/1.1643388 ◽

2004 ◽

Vol 126 (1) ◽

pp. 120-128 ◽

Cited By ~ 3

Author(s):

Marcus M. K. Lee ◽

Ellen M. Dexter

Keyword(s):

Finite Element ◽

Parametric Study ◽

Finite Element Modelling ◽

International Organization ◽

Element Modelling ◽

Calibration And Validation ◽

Tubular Joints ◽

Modelling Procedure ◽

Test Database

This paper describes the calibration and validation of a finite-element modelling procedure that was used to conduct an extensive parametric study on the strength of multi-planar tubular joints. Various factors that influenced results were investigated. The modelling procedure was calibrated using the International Organization for Standards (ISO) design equations and the underlying test database for compression and tension loaded simple T and Y joints, and was further validated with balanced loaded K joints. Overall, the proposed procedure has been shown to be adequate in predicting the strength of the basic joint types, thereby giving confidence in its use for more complex joints.

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Impact of Different Boundary Conditions on the Response of Glare Fiber-Metal Laminates under Lateral Indentation

Advanced Composites Letters ◽

10.1177/096369351602500201 ◽

2016 ◽

Vol 25 (2) ◽

pp. 096369351602500

Author(s):

George S.E. Bikakis ◽

Alexander Savaidis

Keyword(s):

Finite Element ◽

Boundary Conditions ◽

Finite Element Modelling ◽

Strain Energy ◽

Tensile Fracture ◽

Element Modelling ◽

Different Boundary Conditions ◽

Simply Supported ◽

Modelling Procedure ◽

Load Indentation

In this paper, a finite element modelling procedure is implemented in order to predict the static load-indentation curves and the defection shape of simply supported circular GLARE fibre-metal laminates subjected to lateral indentation by a hemispherical indentor. ANSYS software is used and a non-linear analysis is employed with geometric and material non-linearities for FEM calculations. The finite element modelling procedure is applied to GLARE 2–2/1–0.3 and to GLARE 3–3/2–0.4 simply supported circular plates with various diameters. It is found that the simply supported circular GLARE plates deform axisymmetrically from the beginning of the indentation process up to the point of their first failure due to glass-epoxy tensile fracture. By comparison of the obtained load-indentation curves to corresponding previously published load-indentation curves of clamped circular GLARE plates, the effect of the different boundary conditions on their lateral indentation response is studied. Furthermore, the strain energy-indentation curves of the considered circular GLARE 2 and GLARE 3 plates with simply supported and clamped boundaries are calculated and compared. It is found that the simply supported GLARE plates have reduced stiffness and demonstrate an increased first failure defection due to glass-epoxy tensile fracture versus the clamped GLARE plates, whereas the first failure load is not significantly affected by the different boundary conditions. It is also found that for the same lateral indentation, simply supported GLARE plates absorb lower strain energy levels than clamped GLARE plates. Referring to a specific lateral indentation level, the influence of the different boundary support on the corresponding indentation load and the absorbed strain energy is strong and can reach a deviation level of 45 % between the two support types. To our knowledge, a research concerning the response of simply supported GLARE plates under lateral indentation has not been published elsewhere.

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