Comparing Study of Energy-Absorbing Behavior for Honeycomb Structures

2011 ◽  
Vol 462-463 ◽  
pp. 13-17 ◽  
Author(s):  
Yan Wang ◽  
P. Xue ◽  
J.P. Wang

Honeycomb materials,as a type of ultra-light multifunctional material,have been examined extensively in recent years and have been applied in many fields. This study investigated the energy absorption capacity and their mechanisms of honeycomb structures with five different cell geometry (square,triangular,circular, hexagonal,kagome). It has been shown that the honeycomb structure with kagome cells is the best choice under the targets of the energy absorption capacity, peak force and plateau stress, when relative density and cell wall thickness of the five kinds of honeycombs are the same. Besides, honeycomb with hexagonal cells and honeycomb with triangular cells are also ideal structures for energy absorption purpose.

Author(s):  
Ramin Hamzehei ◽  
Ali Zolfagharian ◽  
Soheil Dariushi ◽  
Mahdi Bodaghi

Abstract This study aims at introducing a number of two-dimensional (2D) re-entrant based zero Poisson’s ratio (ZPR) graded metamaterials for energy absorption applications. The metamaterials’ designs are inspired by the 2D image of a DNA molecule. This inspiration indicates how a re-entrant unit cell must be patterned along with the two orthogonal directions to obtain a ZPR behavior. Also, how much metamaterials’ energy absorption capacity can be enhanced by taking slots and horizontal beams into account with the inspiration of the DNA molecule’s base pairs. The ZPR metamaterials comprise multi-stiffness unit cells, so-called soft and stiff re-entrant unit cells. The variability in unit cells’ stiffness is caused by the specific design of the unit cells. A finite element analysis (FEA) is employed to simulate the deformation patterns of the ZPRs. Following that, meta-structures are fabricated with 3D printing of TPU as hyperelastic materials to validate the FEA results. A good correlation is observed between FEA and experimental results. The experimental and numerical results show that due to the presence of multi-stiffness re-entrant unit cells, the deformation mechanisms and the unit cells’ densifications are adjustable under quasi-static compression. Also, the structure designed based on the DNA molecule’s base pairs, so-called structure F''', exhibits the highest energy absorption capacity. Apart from the diversity in metamaterial unit cells’ designs, the effect of multi-thickness cell walls is also evaluated. The results show that the diversity in cell wall thicknesses leads to boosting the energy absorption capacity. In this regard, the energy absorption capacity of structure ‘E’ enhances by up to 33% than that of its counterpart with constant cell wall thicknesses. Finally, a comparison in terms of energy absorption capacity and stability between the newly designed ZPRs, traditional ZPRs, and auxetic metamaterial is performed, approving the superiority of the newly designed ZPR metamaterials over both traditional ZPRs and auxetic metamaterials.


2015 ◽  
Vol 2015 ◽  
pp. 1-7
Author(s):  
Zhi-geng Fan ◽  
Li-xin Lu ◽  
Jun Wang

The effect of fatigue damage (FD) on the energy absorption properties of precompressed honeycomb paperboard is investigated by fatigue compression experiments. The constitutive relations of honeycomb paperboard have been changed after the fatigue damage. The results show that FD has effect on plateau stress and energy absorption capacity of honeycomb paperboard after fatigue cycles but has no significant effect on densification strain. Energy absorption diagram based on the effect of FD is constructed from the stress-strain curves obtained after fatigue compression experiments. FD is a significant consideration for honeycomb paperboard after transports. The results of this paper could be used for optimization design of packaging materials.


2013 ◽  
Vol 437 ◽  
pp. 158-163
Author(s):  
Wei Liang Dai ◽  
Xu Guang Li ◽  
Qing Chun Wang

Energy absorbing characteristics of the non-stiffened and stiffened single hat sections subjected to quasi-static axial crushing were experimentally investigated. First non-stiffened hat sections were axially crushed, then structures with different stiffened methods (stiffened in hat and stiffened in the plate) were tested, finally energy absorption capacities of these structures were compared. Test results showed that, for the appropriate designed stiffened tube, the mean crush force and mass specific energy absorption were increased significantly compared to the non-stiffened. Stiffened in hat section showed a little more energy absorption capacity than that stiffened in the plate, but the structure may sustain a global bending.


Author(s):  
Muhammad Ali ◽  
Eboreime Ohioma ◽  
Khairul Alam

Square tubes are primarily used in automotive structures to absorb energy in the event of an accident. The energy absorption capacity of these structural members depends on several parameters such as tube material, wall thickness, axial length, deformation modes, locking strain, crushing stress, etc. In this paper, the work presented is a continuation of research conducted on exploring the effects of the introduction of cellular core in tubular structures under axial compressive loading. Here, the crushing response of composite cellular core tube was numerically studied using ABAQUS/Explicit module. The energy absorbing characteristics such as deformation or collapsing modes, crushing/ reactive force, crushing stroke, and energy curves were discussed. The composite cellular core tube shows promise for improving the crashworthiness of automobiles.


Author(s):  
J. Clark ◽  
S. Jenson ◽  
J. Schultz ◽  
J. Hoffman ◽  
S. Takak ◽  
...  

The work presented in this paper is a continuation of the study conducted on exploring impact properties of a functionally graded bio cellular structure found in a banana peel. The graded cellular structure with unfilled cells reacts intelligently to impact loading and crushes in a manner that results in a higher amount of energy absorption as compared to an equivalent regular honeycomb structure. In this paper, a non-Newtonian fluid is introduced into the cells of a regular honeycomb structure, and its effect on energy absorption properties are studied using an experimental approach. The results are compared with impact mitigation properties of an unfilled regular honeycomb structure. The introduction of non-Newtonian fluid significantly enhances the energy absorption capacity of regular honeycomb structure, and therefore, suggests that fluid inside a banana peel structure is playing a critical role in energy and impact absorption. A rudimentary relationship between the numbers of fluid filled layers and total energy absorption capacity of the structure is presented through a regression analysis.


Author(s):  
J. M. Kelly ◽  
R. I. Skinner ◽  
A. J. Heine

A structure designed to resist earthquake attack must have a capacity to dissipate kinetic energy induced by the ground motion. In most structures this energy absorption is developed in the vicinity of beam to column connections. Recent research has shown that connections are not reliable when subject to cyclic loading, such as results from earthquake attack. Connections in steel frames deteriorate due to local instabilities in adjacent flanges, and in reinforced concrete frames alternating shear
loads produce diagonal tension and bond failures which progressively reduce the strength of the connection. Much work in building research and earthquake engineering in laboratories throughout the world is directed toward increasing the reliability and energy absorption capacity of structural connections. In this paper an alternative approach to this problem is described. This approach is to separate the load carrying function of the structure from the energy absorbing function and to ask if special devices could be incorporated into the structure with the sole purpose of absorbing the kinetic energy generated in the structure by earthquake attack. To determine whether such devices are feasible a study has been undertaken of three essentially different mechanisms of energy absorption. These mechanisms all utilized the plastic deformation of mild steel. They included the rolling of strips, torsion of square and rectangular bars,
 and the flexure of short thick beams. These mechanisms were selected for intensive study since they were basic to three different types of device each of which was designed for a separate mode of operation in a structural system. The characteristics of these mechanisms which were of primary importance in this study were the load displacement relations, the energy absorption capacity and the fatigue resistance. This information was obtained with a view to the development of devices for specific structural applications. This report describes the tests used to explore the basic mechanisms and the data obtained. It also include s a brief description of tests on scale models of a device which was designed to be located in the piers of a reinforced concrete railway bridge. It has been shown by the tests that the plastic torsion of mild steel is an extremely efficient mechanism for the absorption of energy. It was found that at plastic strains in the range 3% to 12% it was possible to develop energy dissipation of the order of 2000-7500 lb in/in3 per cycle (14-50 x 106 N/M2 per cycle) with lifetimes within the range of 1000 to 100 cycles. It was also shown that the mode of failure in torsion is an extremely favourable one for use in an energy absorbing device in that it took the form of a gradual decay. The other two mechanisms studied were both less efficient and less reliable than torsion and had capacities of 500-2000 lb in/in3 per cycle (3.5 - 14 x 106 N/M2 per cycle) and life times of around 200 to 20 cycles. Nevertheless they lend themselves to more compact devices than does the torsional mechanism and furthermore the devices may be located in regions in a structure where they are readily accessible for replacement after attack.


The aim of this study is to examine the effect of fiber mat’s density and deformation mechanism of tubes with and without die compression. In this study a new mode of deformation mechanism of density graded GFRP circular tube is examined when they are subjected to axial compression on to a die and without die to examine its energy absorbing capacity. Theoretical calculations were made to predict the crushing stress of different specimens. It is observed that increasing density of fiber increases energy absorption value but decreases the specific energy absorption and the die could trigger progressive crushing additionally decreasing peak load. Here the compressed tube wall is compelled to be deformed towards the end of compression die with a little range of bending curvature which was forced by the radius of the die at high crushing stress and the major part of the deformation takes place at a nearly constant load, which leads to high energy absorption capacity. Comparison between theoretical prediction values by derived equations and the experimental results shows good correlation.


2021 ◽  
Author(s):  
Ali Rashidian ◽  
Khandaker M. Anwar

This research studied the shear and flexural behaviour of fiber reinforced lightweight self-consolidating concrete (FRLWSCC) beams made of three different fibers such as: High-Density Poly Ethylene (HDPE), Crumb Rubber (CR) and Polyvinyl Alcohol (PVA) compared with lightweight self-consolidating concrete (LWSCC) beams. The performances of all beams were described based on load-deformation or moment-rotation response, strain developments, crack characterization, failure modes, ductility, stiffness and energy absorbing capacity. All FRLWSCC shear beams showed higher ultimate shear resistance, ductility and energy absorption capacity compared to LWSCC beams. All FRLWSCC flexural beams at failure exhibited higher flexural capacity, more cracks with smaller width, higher ductility, higher energy absorption capacity and lower stiffness compared to their LWSCC counterparts. FRLWSCC beams especially made of HDPE fibers showed better shear and flexural capacities besides satisfactory ductility performance. Experimental shear and flexural capacities of FRLWSCC beams were compared with those predicted from Code based and other existing equations.


Crystals ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1074
Author(s):  
Naoko Ikeo ◽  
Tatsuya Matsumi ◽  
Takuya Ishimoto ◽  
Ryosuke Ozasa ◽  
Aira Matsugaki ◽  
...  

In this study, a Ti–6Al–4V alloy composite with uniaxial anisotropy and a hierarchical structure is fabricated using electron beam powder bed fusion, one of the additive manufacturing techniques that enable arbitrary fabrication, and subsequent heat treatment. The uniaxial anisotropic deformation behavior and mechanical properties such as Young’s modulus are obtained by introducing a unidirectional honeycomb structure. The main feature of this structure is that the unmelted powder retained in the pores of the honeycomb structure. After appropriate heat treatment at 1020 °C, necks are formed between the powder particles and between the powder particles and the honeycomb wall, enabling a stress transmission through the necks when the composite is loaded. This means that the powder part has been mechanically functionalized by the neck formation. As a result, a plateau region appears in the stress–strain curve. The stress transfer among the powder particles leads to the cooperative deformation of the composites, contributing to the excellent energy absorption capacity. Therefore, it is expected that the composite can be applied to bone plates on uniaxially oriented microstructures such as long bones owing to its excellent energy absorption capacity and low elasticity to unidirectionally suppress stress shielding.


2008 ◽  
Vol 22 (09n11) ◽  
pp. 1730-1735 ◽  
Author(s):  
KUNIHARU USHIJIMA ◽  
DAI-HENG CHEN ◽  
HIRONOBU NISITANI

In this paper, a new type of honeycomb structure is proposed to enhance the energy absorption capacity for a honeycomb structure, and investigated its energy absorption efficiency (absorbed energy per unit volume) by finite element method (FEM). This model has small arc-shaped parts on the double cell wall, and can be manufactured by a similar way of standard honeycomb structures. Also, the proposed structure has large rigidity of plastic bending without increasing the mass. In this paper, effects of geometrical properties on the energy absorption characteristics are discussed.


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