Experimental analysis on the axial crushing and energy absorption characteristics of novel hybrid aluminium/composite-capped cylindrical tubular structures

2019 ◽  
Vol 233 (11) ◽  
pp. 2234-2252 ◽  
Author(s):  
A Praveen Kumar
Keyword(s):  
Energy Absorption ◽  
Specific Energy ◽  
Cylindrical Tube ◽  
Tubular Structures ◽  
Aluminium Composite ◽  
Specific Energy Absorption ◽  
Cylindrical Tubes ◽  
Impact Crushing ◽  
Energy Absorbing ◽  
The Impact

In recent years, aluminium-composite hybrid tubular structures, which combine the stable and progressive plastic deformation of the aluminium metal with light-weight composite materials, are obtaining increased consideration for meeting the advanced needs of crashworthiness characteristics. This research article presents the experimental outcomes of novel aluminium/composite-capped cylindrical tubes subjected to quasi-static and impact axial loads. The influence of various capped geometries in the aluminium segment and three different fabrics of the composite segment in the cylindrical tube are investigated experimentally. The outcomes of the impact crushing test are also correlated with the quasi-static results of the proposed aluminium/composite-capped cylindrical tubes. The overall outcomes revealed that the crashworthiness characteristics of crushing force consistency and specific energy absorption of the aluminium-composite hybrid tubes are superior to those of the bare aluminium tubes. When the glass fabric/epoxy composite is wrapped to aluminium cylindrical tubes, the specific energy absorption increases about 23–30%, and the wrapping of hybrid glass/kenaf fabrics increases the specific energy absorption of almost 40–52%. Such a hybrid tubular structures would be of huge prospective to be used as effective energy-absorbing devices in aerospace and automotive applications. A further benefit of the composite-wrapping approach is that the composite might be retro-fitted to aluminium tubes, and the energy absorption capability is shown to be significantly enhanced by such utilization.

Dynamic Axial Compression of Square CFRP/Aluminium Tubes

2019 ◽  
Vol 794 ◽  
pp. 202-207
Author(s):  
Rafea Dakhil Hussein ◽  
Dong Ruan ◽  
Guo Xing Lu ◽  
Jeong Whan Yoon ◽  
Zhan Yuan Gao
Keyword(s):  
Energy Absorption ◽  
Specific Energy ◽  
Fibre Composite ◽  
Dynamic Tests ◽  
Carbon Fibre Composite ◽  
Specific Energy Absorption ◽  
Static Tests ◽  
Crushing Force ◽  
Cfrp Tubes ◽  
The Impact

Carbon fibre composite tubes have high strength to weight ratios and outstanding performance under axial crushing. In this paper, square CFRP tubes and aluminium sheet-wrapped CFRP tubes were impacted by a drop mass to investigate the effect of loading velocity on the energy absorption of CFRP/aluminium tubes. A comparison of the quasi-static and dynamic crushing behaviours of tubes was made in terms of deformation mode, peak crushing force, mean crushing force, energy absorption and specific energy absorption. The influence of the number of aluminium layers that wrapped square CFRP tubes on the crushing performance of tubes under axial impact was also examined. Experimental results manifested similar deformation modes of tubes in both quasi-static and dynamic tests. The dynamic peak crushing force was higher than the quasi-static counterpart, while mean crushing force, energy absorption and specific energy absorption were lower in dynamic tests than those in quasi-static tests. The mean crushing force and energy absorption decreased with the crushing velocity and increased with the number of aluminium layers. The impact stroke (when the force starts to drop) decreased with the number of aluminium layers.

Crashworthiness performance of concentric structures with different cross-sectional shapes under multiple loading conditions

2020 ◽  
pp. 095440702096188
Author(s):  
Sadjad Pirmohammad
Keyword(s):  
Energy Absorption ◽  
Specific Energy ◽  
Absorption Maximum ◽  
Element Model ◽  
Hexagonal Structure ◽  
Loading Conditions ◽  
Cross Sectional ◽  
Specific Energy Absorption ◽  
Multiple Loading ◽  
Energy Absorbing

This paper evaluates the crashworthiness performance of concentric structures with different numbers of tubes (i.e. one to five) and cross-sectional shapes (i.e. hexagon, octagon, decagon and circle) under the multiple loadings of θ = 0, 10, 20 and 30°. An experimentally validated finite element model generated in LS-DYNA is employed to calculate the crashworthiness parameters including the specific energy absorption, maximum crush force and crush force efficiency. A total of 20 concentric structures are analyzed to explore the effects of number of tubes and cross-sectional shapes on the crushing performance. A multi-criteria decision-making method known as TOPSIS is also used to compare and rank the concentric structures in terms of crushing performance. Based on the results, the hexagonal structure including two tubes and octagonal, decagonal and circular structures including three tubes demonstrate the best results among their corresponding cross-sectional shapes. These structures show 9, 39, 38 and 39% higher specific energy absorption compared to their corresponding single tubal cases, respectively. However, in comparison to single tubal cases, they generate 4, 57, 57 and 58% higher maximum crush force, respectively. As such, the values for the improvement of the crush force efficiency are 3, 26, 25 and 21%, respectively. Furthermore, the decagonal structure including three tubes provides the highest energy absorbing characteristics as compared with all the other structures studied in this research. Meanwhile, taking into account all the multiple loading conditions, this structure shows 50% higher specific energy absorption than the hexagonal structure including single tube (as the weakest structure).

Effect of the Fine Recycled Aggregates on the Dynamic Compressive Behavior of Recycled Mortar

2020 ◽  
Vol 991 ◽  
pp. 62-69
Author(s):  
Sallehan Ismail ◽  
Mohamad Asri Abd Hamid ◽  
Zaiton Yaacob
Keyword(s):  
Compressive Strength ◽  
Strain Rate ◽  
Energy Absorption ◽  
Specific Energy ◽  
Split Hopkinson Pressure Bar ◽  
Recycled Aggregates ◽  
Fine Aggregate ◽  
Peak Strain ◽  
Specific Energy Absorption ◽  
The Impact

This study aims to investigate the dynamic behavior of recycled mortar under impact loading using a split Hopkinson pressure bar (SHPB). Several mortar mixtures were produced by adding various fine recycled aggregates (FRA) to the mixture in replacement percentages of 0%, 25%, 50%, 75%, and 100% of the natural fine aggregate (NFA). The effects of strain rate on compressive strength and specific energy absorption were obtained. Results show that the dynamic compressive strength and specific energy absorption of recycled mortar are highly strain rate dependent; specifically, they increase nearly linearly with the increase in peak strain rate. However, the compressive strength and specific energy absorption of recycled mortar are generally lower than those of NFA mortar (reference samples) under similar high strain rates. The findings of this research can help researchers and construction practitioners to ascertain the appropriate mix design procedure to optimize the impact strength properties of recycled mortar for protective structural application.

scholarly journals Parameters Affecting the Specific Energy Absorption of Circular Side Impact Beam

2020 ◽  
Vol 9 (3) ◽  
pp. 3399-3405
Keyword(s):  
Energy Absorption ◽  
Specific Energy ◽  
Circular Cross Section ◽  
Side Impact ◽  
Vehicle Body ◽  
Specific Energy Absorption ◽  
Side Door ◽  
Frontal Collision ◽  
Side Collision ◽  
The Impact

In vehicle design, safety of occupants is one of the most important criteria. During side collisions, space between vehicle body and occupants is very less as compared to frontal collision. Hence, scope for energy absorption due to deformation of vehicle body in side collisions is less. The strength of side door plays important role in the framework of vehicle side body. The strength of side doors during side collision depends upon the impact beam, vehicle construction, layout of doors etc. Among the mentioned parameters, strength of impact beam is a crucial parameter. The impact beam absorbs notable amount of impact energy by deforming during side collision. Design of side impact beam should be optimum as it is limited by weight of vehicle. Parameters like material, dimensions, shape and mountings of beam inside the door are affecting the strength of side impact beam. In this work parameters of circular cross-section impact beam like diameter of beam, thickness of beam and angle of mounting inside the door are studied. Finite element simulation of side impact beam is done in ABAQUS software and its relative effects on Specific Energy Absorption (SEA) capacity of beam is studied. The simulation results are validated with available literatures. The ANOVA analysis followed by Design of Experiments is used to determine contribution of each parameter on SEA. Further various parameters of circular impact beam are studied by examining the result analysis for crashworthiness of side door.

Energy-Absorbing Characteristics of the Stiffened Thin-Walled Tubes Subjected to Axial Crushing

2013 ◽  
Vol 437 ◽  
pp. 158-163
Author(s):  
Wei Liang Dai ◽  
Xu Guang Li ◽  
Qing Chun Wang
Keyword(s):  
Energy Absorption ◽  
Specific Energy ◽  
Absorption Capacity ◽  
Test Results ◽  
Energy Absorption Capacity ◽  
Specific Energy Absorption ◽  
Axial Crushing ◽  
The Mean ◽  
Thin Walled ◽  
Energy Absorbing

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.

Experimental Investigation on the Crashworthiness of Braided Glass/Epoxy Tubes Subjected to Axial Impacting

2014 ◽  
Vol 23 (2) ◽  
pp. 096369351402300
Author(s):  
Ping Zhang ◽  
Liang-Jin Gui ◽  
Zi-Jie Fan ◽  
Jing-Yu Liu
Keyword(s):  
Energy Absorption ◽  
Specific Energy ◽  
Failure Modes ◽  
Impact Load ◽  
Peak Load ◽  
Low Velocity Impact ◽  
Test Results ◽  
Specific Energy Absorption ◽  
The Mean ◽  
The Impact

This paper presented an experimental study on the low-velocity impact response of triaxial braided composite circular tubes, which were fabricated with S-glass/epoxy composite. The impact responses were recorded and analyzed in terms of impact load-displacement curves and specific energy absorption. In addition, four basic failure modes called delaminating, splaying, fragmental fracture and progressive folding were founded. The levels of the mean impact load and specific energy absorption (SEA) are determined by the energy absorption mechanisms, which are related to the dominant failure modes of the tubes. In general, delamination which exhibits the poor energy absorbing performance is the dominant failure mode for all the specimens. Impact test results showed that all three types of tubes had almost the same SEA. Compared to the quasi-static test results, the first peak load and the mean load decrease at about 50% and 10% respectively, SEA generally decreases at an average level 10%.

Improving the energy-absorbing properties of hybrid aluminum-composite tubes using nanofillers for crashworthiness applications

2020 ◽  
pp. 095440622094226
Author(s):  
A Praveen Kumar ◽  
D Maneiah ◽  
L Ponraj Sankar
Keyword(s):  
Energy Absorption ◽  
Metal Composite ◽  
Multiwalled Carbon ◽  
Aluminum Composite ◽  
Basalt Glass ◽  
Cylindrical Tubes ◽  
Thin Walled ◽  
Crushing Behavior ◽  
Energy Absorbing ◽  
The Impact

Thin-walled tubular configurations with hybridization concept have been gained special consideration in recent years owing to their substantial balance between light-weight characteristics and crashworthiness performance. In this context, some research studies have been concentrated on the feasibility of a thin-walled metal-composite hybrid tube. It is also eminent that the impact energy absorption capability of such hybrid tubes can further be enhanced through modification of the epoxy matrix by adding nanofillers. In this research article, aluminum-based multiwalled carbon nanotubes reinforced epoxy composite cylindrical tubes are introduced, and their corresponding quasi-static crushing behavior, subjected to lateral loading is examined experimentally. The influence of the number of fabric plies (2, 3, and 4) and type of fabric (basalt, glass) of the composite part on the crashworthiness characteristics was evaluated. The overall outcomes revealed that the proposed hybrid tube samples showed outstanding energy absorption characteristics, comprising a stable crush force–deformation response and better specific energy absorption. It is also noted that the deformation behavior and energy absorption capability of the aluminum tubes could be considerably improved by applying a nanocomposite-wrapped plies.

Energy absorption in aluminium honeycomb cores reinforced with carbon fibre reinforced plastic tubes

2017 ◽  
Vol 21 (8) ◽  
pp. 2801-2815 ◽  
Author(s):  
A Alantali ◽  
RA Alia ◽  
R Umer ◽  
WJ Cantwell
Keyword(s):  
Carbon Fibre ◽  
Energy Absorption ◽  
Specific Energy ◽  
Small Diameter ◽  
Honeycomb Core ◽  
Composite Tubes ◽  
Specific Energy Absorption ◽  
Reinforced Plastic ◽  
Carbon Fibre Reinforced Plastic ◽  
Energy Absorbing

The energy-absorbing behaviour of an aluminium honeycomb core reinforced with unidirectional and woven carbon fibre reinforced plastic composite tubes has been investigated experimentally at quasi-static rates of strain. Small diameter carbon fibre reinforced plastic tubes, with chamfered ends, were inserted into the cells of an aluminium honeycomb in order to yield a lightweight energy-absorbing material. The resulting data are compared with crushing tests on arrays of free-standing composite tubes, supported on a specially designed compression test fixture. The study continues with an investigation into size effects in the energy-absorbing response of these cellular materials, where compression tests are undertaken on four scaled sizes of reinforced honeycomb core. Crushing tests on the multi-tube arrays have shown that woven carbon fibre reinforced plastic tubes absorb significantly greater levels of energy than their unidirectional counterparts. Here, the specific energy absorption did not vary with the number of tubes in the array, with values for the woven tubes averaging 110 kJ/kg and those for the unidirectional tubes averaging 75 kJ/kg. Inserting composite tubes into aluminium honeycomb served to increase the measured specific energy absorption of the core, resulting in values of specific energy absorption of up to 100 kJ/kg being recorded in the woven-based system. Tests on four scaled sizes of core have shown that the measured SEA does not vary with specimen size, indicating that data generated on small samples can be used to represent the energy-absorbing response of larger, more representative components.

The effect of loading rate on the compression properties of carbon fibre-reinforced epoxy honeycomb structures

2020 ◽  
Vol 54 (19) ◽  
pp. 2565-2576 ◽  
Author(s):  
RA Alia ◽  
J Zhou ◽  
ZW Guan ◽  
Q Qin ◽  
Y Duan ◽  
...  
Keyword(s):  
Carbon Fibre ◽  
Strain Rate ◽  
Energy Absorption ◽  
Specific Energy ◽  
Compression Strength ◽  
Loading Rate ◽  
Specific Energy Absorption ◽  
Honeycomb Cores ◽  
Energy Absorbing ◽  
Absorption Characteristics

The effect of varying strain rate on the compression strength and energy absorption characteristics of a carbon fibre-reinforced plastic honeycomb core has been investigated over a wide range of loading rates. The honeycombs were manufactured by infusing an epoxy resin through a carbon fibre fabric positioned in a dismountable honeycomb mould. The vacuum-assisted resin transfer moulding technique yielded honeycomb cores of a high quality with few defects. Compression tests were undertaken on single and multiple cells and representative volumes removed from the cores in order to assess how the compression strength and specific energy absorption vary with test rate. Crushing tests over the range of strain rates considered highlighted the impressive strength and energy-absorbing response of the honeycomb cores. At quasi-static rates of loading, the compression strength and specific energy absorption characteristics of the unidirectional samples exceeded those of the multidirectional cores. Here, extensive longitudinal splitting and fibre fracture were the predominant failure mechanisms in the cores. For all three stacking sequences, the single-cell samples offer higher compression strength than their five-cell counterparts. In contrast, the specific energy absorption values were found to be slightly higher in the five-cell cores. The experiments highlighted a trend of increased compression strength with loading rate in the multidirectional samples, whereas the strength of the [0°]4 samples was relatively insensitive to strain rate. Finally, the energy absorbing capacity of all structures studied was found to be reasonably constant at increasing rates of strain.

The crushing characteristics of reinforced Nomex honeycomb

2018 ◽  
Vol 37 (20) ◽  
pp. 1267-1276 ◽  
Author(s):  
RA Alia ◽  
S Rao ◽  
R Umer ◽  
J Zhou ◽  
C Zheng ◽  
...  
Keyword(s):  
Energy Absorption ◽  
Specific Energy ◽  
Compression Strength ◽  
Small Diameter ◽  
Areal Density ◽  
Mechanical Tests ◽  
Stable Model ◽  
Specific Energy Absorption ◽  
Nomex Honeycomb ◽  
Energy Absorbing

A Nomex honeycomb core has been reinforced with small diameter composite rods and tubes in order to enhance its compression properties and energy-absorbing characteristics. The influence of the areal density of the rods and tubes on the strength and energy-absorbing properties of the reinforced honeycomb was investigated by introducing increasing numbers of rods/tubes in square samples with bonded composite skins. An initial series of crushing tests on arrangements of small tubes and rods resulted in a stable model of failure yielding specific energy absorption values of approximately 45 kJ/kg for the tube and rod-based structures. A subsequent observation of the failed tubes highlighted the similar failure processes to those observed previously following the tests on much larger composite cylinders. Mechanical tests on the Nomex cores have shown that the compression strength and energy-absorbing characteristics of the reinforced honeycombs increase rapidly with increasing composite reinforcement. At low and intermediate values of core density, the rod and tube-reinforced cores exhibited similar properties, in terms of their compression strengths and specific energy absorption, an effect that is likely to be due to the dominance of the heavier Nomex core in these samples. At higher densities, the rod-reinforced systems tended to out-perform their tube-reinforced counterparts. Tests at impact rates of strain have shown that the compression strength and energy-absorbing capabilities of the reinforced cores are higher under the dynamic conditions, with the rod-reinforced cores offering values of specific energy absorption as high as 78 kJ/kg.

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