Influence of longitudinal edge profiling in sandwich panels on interpretation of experimental results

This paper presents a parametric study for the bending stiffness of mineral wool (MW) sandwich panels subjected to a bending load. The MW panels are commonly used as wall panels for industrial buildings. They provide excellent insulation in the case of fire. In this research, the performance of sandwich panels is investigated at both ambient and elevated temperatures. To reach that goal, a finite element (FE) model is developed to verify simulations with experimental results in normal conditions and fire case. The experimental investigation in the current paper is a part of STABFI project financed by Research Fund for Coal and Steel (RFCS). The numerical study is conducted using ABAQUS software. Employing simulations for analysis and design is an alternative to costly tests. However, in order to rely on numerical results, simulations must be verified with the experimental results. In this paper, after the verification of FE results, a parametric study is conducted to observe the effects of the panel thickness, length and width, as well as the facing thickness on the bending stiffness of MW sandwich panels at normal conditions. The results indicate that the panel thickness has the most significant effect on the bending stiffness of sandwich panels.

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Ferrocement sandwich and hollow core panels for floor construction

Canadian Journal of Civil Engineering ◽

10.1139/cjce-2011-0016 ◽

2012 ◽

Vol 39 (12) ◽

pp. 1297-1310 ◽

Cited By ~ 9

Author(s):

Ezzat H. Fahmy ◽

Yousry B.I. Shaheen ◽

Mohamed N. Abou Zeid ◽

Hassan M. Gaafar

Keyword(s):

Lightweight Concrete ◽

Steel Wire ◽

Research Work ◽

Sandwich Panels ◽

Experimental Results ◽

Wire Mesh ◽

Hollow Core ◽

Circular Holes ◽

Good Energy ◽

Steel Wire Mesh

This paper presents the results of a research work to develop ferrocement sandwich and hollow core panels for use as precast one way slab elements. Sandwich panels consisted of two thin ferrocement layers reinforced with steel wire mesh and a core of autoclaved aerated lightweight concrete bricks. The hollow core panels are made of the same ferrocement mortar matrix with three circular holes of 75 mm diameter running along the length of the specimen. A total of 15 sandwich panels and 12 hollow core panels were cast and tested under flexural loadings. The experimental results showed that high ultimate and service loads, crack resistance control, high ductility, and good energy absorption could be achieved by using the proposed panels. A theoretical model based on the ultimate strength method for reinforced concrete was developed to determine the ultimate moment and mode of failure of the panels. The theoretical and experimental results showed good agreement.

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Local Effects during Indentation of Fully Supported Sandwich Panels with Micro Lattice Cores

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.13-14.85 ◽

2008 ◽

Vol 13-14 ◽

pp. 85-90 ◽

Cited By ~ 12

Author(s):

Robert A.W. Mines ◽

S. McKown ◽

S. Tsopanos ◽

E. Shen ◽

Wesley J. Cantwell ◽

...

Keyword(s):

Lattice Structure ◽

Sandwich Panels ◽

Cellular Materials ◽

Aluminium Foam ◽

Experimental Results ◽

Foreign Object ◽

Local Effects ◽

Static Penetration ◽

Penetration Behavior ◽

Composite Skins

This paper discusses the penetration behavior of fully supported sandwich panels with micro-lattice and foam cores, and composite skins. This behaviour is of importance during foreign object impact and perforation of sandwich structures. Experimental results are given for quasi-static penetration of micro-lattice and foam blocks, and it is shown that these two cellular materials are comparable. Experimental results are also given for drop weight penetration of fully supported skinned panels, and it is shown that skin failure and core penetration are also similar for the two core materials. It is concluded that there is scope for improving the performance of micro-lattice structure and so making such material superior to that of aluminium foam.

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Nonlinear vibration analysis of circular/annular/sector sandwich panels incorporating magnetorheological fluid operating in the post-yield region

Journal of Intelligent Material Systems and Structures ◽

10.1177/1045389x20975471 ◽

2020 ◽

pp. 1045389X2097547

Author(s):

Reza Aboutalebi ◽

Mehdi Eshaghi ◽

Afshin Taghvaeipour

Keyword(s):

Magnetic Field ◽

Nonlinear Vibration ◽

Dynamic Characteristics ◽

Sandwich Structures ◽

Sandwich Panels ◽

Core Layer ◽

Experimental Results ◽

Mr Fluid ◽

Maximum Deformation ◽

Annular Sector

This study offers a comprehensive analysis on the nonlinear vibratory behavior of circular, annular, and sector sandwich panels containing magnetorheological (MR) fluid as the core layer. Due to the large deformation experienced by the sandwich structures, the MR fluid operates in the post-yield region, in which the shear strain and shear stress are nonlinearly dependent. The post-yield characteristics of the MR fluid are quantified using the experimental results available in the literature. The present study also employs the experimental results presented in the literature on the dynamic characteristics of a MR based sandwich circular plate to demonstrate accuracy of the results. To identify governing equations of motion of the structures, a finite element approach based on von Karman formulations is employed. Moreover, displacement control strategy is used to solve the extracted nonlinear equations and evaluate dynamic characteristics of the MR based circular/annular/sector sandwich plates in terms of resonant frequencies and loss factors. This study highlights the effect of post-yield behavior of the MR fluid in the nonlinear vibration attenuation of MR sandwich structures, under different levels of magnetic field. Also, the effects of maximum deformation and magnetic field on the functionality of the MR fluid are comprehensively investigated.

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Laterally supported sandwich panels subjected to large deflections—Part 1: Test apparatus design and experimental results

Thin-Walled Structures ◽

10.1016/j.tws.2007.08.045 ◽

2008 ◽

Vol 46 (4) ◽

pp. 413-422 ◽

Cited By ~ 2

Author(s):

Tito Lívio Boni ◽

Sérgio Frascino Müller de Almeida

Keyword(s):

Sandwich Panels ◽

Experimental Results ◽

Large Deflections ◽

Test Apparatus ◽

Apparatus Design

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High-order crack propagation in compressed sandwich panels

Journal of Sandwich Structures & Materials ◽

10.1177/1099636218824873 ◽

2019 ◽

Vol 21 (5) ◽

pp. 1726-1750 ◽

Cited By ~ 5

Author(s):

Itay Odessa ◽

Oded Rabinovitch ◽

Yeoshua Frostig

Keyword(s):

Geometrical Nonlinearity ◽

Sandwich Panels ◽

Interfacial Crack ◽

Interfacial Debonding ◽

High Order ◽

Experimental Results ◽

Face Sheet ◽

Interfacial Instabilities ◽

The Core ◽

The Face

The response and the debonding mechanisms in axially compressed sandwich panels with an interfacial delamination are investigated using a nonlinear model. The mathematical model combines the extended high-order sandwich panel theory with a cohesive interface modeling. It includes the first-order shear deformation kinematic assumptions for the face sheets and high-order small deformations kinematic assumptions that account for out-of-plane compressibility for the core. The interfaces bond the face sheets and the core by means of traction–displacement gap laws. These interfacial laws can describe a diversity of physical conditions. In particular, interfacial debonding nucleation and propagation are described using cohesive laws that introduce the interfacial nonlinearity into the model. Geometrical nonlinearity of the face sheets is introduced in order to capture the instability associated with the buckling of the delaminated face sheet. The cohesive interfaces and others parameters are calibrated to match experimental results taken from the literature for a sandwich specimen subjected to an end-shortening compression. The instabilities due to the in-plane compression, together with the existence of delaminated regions and their tendency to grow, prompt buckling of the delaminated face sheet as well as nucleation and propagation of the interfacial debonding. The theoretical quantification of this complex mechanism compares well with the experimental results in terms of the physical response, the nucleation and propagation of the interfacial crack, and the evolution of local/global geometrical instabilities. In addition, the analysis explores debonding mechanisms that are beyond the capabilities of the experimental technique. Finally, the sensitivity of the response and the associated geometrical and interfacial instabilities to the boundary conditions are investigated.

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Finite Element Simulation of Aluminium Foam Sandwich Panels Subjected to Impact Loading

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.261-263.761 ◽

2011 ◽

Vol 261-263 ◽

pp. 761-764 ◽

Cited By ~ 2

Author(s):

Roger Zou ◽

Dong Ruan ◽

Guo Xing Lu

Keyword(s):

Finite Element ◽

Impact Loading ◽

Sandwich Panels ◽

Aluminium Foam ◽

Experimental Results ◽

Skin Thickness ◽

Fe Model ◽

Element Simulation ◽

Core Thickness ◽

Commercial Software Package

One potential application of aluminium foam sandwich panels in civil engineering is the cladding system which is employed to protect other structures again impact and blast loadings. Finite element (FE) simulation of these sandwich panels subjected to impact loading was conducted by using a commercial software package, LS-DYNA (version 971). The FE model was verified by experimental results conducted previously. Good agreement was achieved between the FE and experimental results. Parametric study was conducted to investigate the effects of skin thickness, core thickness and boundary conditions on the deformation modes and energy absorption of sandwich panels with aluminum foam core.

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Diagnostics of Gold Laser Plasmas

International Astronomical Union Colloquium ◽

10.1017/s0252921100108085 ◽

1988 ◽

Vol 102 ◽

pp. 357-360

Author(s):

J.C. Gauthier ◽

J.P. Geindre ◽

P. Monier ◽

C. Chenais-Popovics ◽

N. Tragin ◽

...

Keyword(s):

Experimental Results ◽

Pure Gold ◽

Electronic Temperature ◽

X Ray ◽

Laser Plasmas ◽

Collisional Radiative Model ◽

Radiative Model

AbstractIn order to achieve a nickel-like X ray laser scheme we need a tool to determine the parameters which characterise the high-Z plasma. The aim of this work is to study gold laser plasmas and to compare experimental results to a collisional-radiative model which describes nickel-like ions. The electronic temperature and density are measured by the emission of an aluminium tracer. They are compared to the predictions of the nickel-like model for pure gold. The results show that the density and temperature can be estimated in a pure gold plasma.

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