An Axial Crushing Characteristics of Hybrid Kenaf/Glass Fabric Wrapped Aluminium Capped Tubes Under Static Loading

Composite tubular structures have shown promise as energy absorbers in the automobile industry. This paper investigates the energy absorption characteristics of carbon fiber reinforced plastic (CFRP) tubes with pre-existing holes. Holes may represent an extreme case of impact damage that perforates the tube, e.g., stones from road surface impacting the tubes. Tubes with holes represent more conservative performance characteristics, since impact damage of the same size will have residual material, which may carry some load. Tubes with holes can provide the lower limit of CFRP tube performance under axial crushing relative to impact damaged tubes with perforation diameter close to the hole diameter. In this study, tubes with lay-up of [05/902/04] with one and two holes in defined locations and different diameters are experimentally studied under quasi-static loading. It was found that specific energy absorption (SEA) reduces by 50% with one or two holes of 15 mm size, 100 mm from top of the tube. The SEA reduction is about 60% lower than the regular tube when the diameter of the hole is 20 mm located at 100 mm from top. The most severe reduction occurs if the location of single or double holes are 75 mm from the top. In this case, a SEA reduction of 75% can be expected. Results indicate that holes can significantly alter the energy absorption capability of the tubes. It is also clear that in axial crushing of composite tubes, the location of the hole (100 to 75 mm) appears to create more pronounced effect than the size of the hole itself (15 vs. 20 mm) for the cases investigated. The failure modes for tubes with holes seem to preserve similar damage modes with delamination, frond creation, and brittle fracture, which is typically observed in regular composite tubes under axial crushing load. This is due to primarily front end crushing, which dominates the failure modes, while hole induced damage occurs later.

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The influence of stiffeners on axial crushing of glass-fabric-reinforced epoxy composite shells

Journal of King Saud University - Engineering Sciences ◽

10.1016/j.jksues.2014.08.001 ◽

2017 ◽

Vol 29 (1) ◽

pp. 91-101

Author(s):

A. Vasanthanathan ◽

P. Nagaraj ◽

K.M. Kabilash ◽

M. Sriram

Keyword(s):

Epoxy Composite ◽

Glass Fabric ◽

Composite Shells ◽

Axial Crushing

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Static axial crushing response on the energy absorption capability of hybrid Kenaf/Glass fabric cylindrical tubes

Materials Today Proceedings ◽

10.1016/j.matpr.2019.12.246 ◽

2020 ◽

Vol 27 ◽

pp. 783-787 ◽

Cited By ~ 1

Author(s):

A. Praveen Kumar ◽

M. Shunmugasundaram ◽

S. Sivasankar ◽

L. Ponraj Sankar

Keyword(s):

Energy Absorption ◽

Glass Fabric ◽

Axial Crushing ◽

Cylindrical Tubes

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Microstructural and fractographic characterization of B4C-Al cermets tested under dynamic and static loading

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100154780 ◽

1989 ◽

Vol 47 ◽

pp. 562-563

Author(s):

Gyeung Ho Kim ◽

Mehmet Sarikaya ◽

D. L. Milius ◽

I. A. Aksay

Keyword(s):

Thin Film ◽

Mechanical Properties ◽

Fracture Toughness ◽

Static Loading ◽

Carbon Deposition ◽

Full Density ◽

Unique Combination ◽

Strong Component ◽

Reaction Products

Cermets are designed to optimize the mechanical properties of ceramics (hard and strong component) and metals (ductile and tough component) into one system. However, the processing of such systems is a problem in obtaining fully dense composite without deleterious reaction products. In the lightweight (2.65 g/cc) B4C-Al cermet, many of the processing problems have been circumvented. It is now possible to process fully dense B4C-Al cermet with tailored microstructures and achieve unique combination of mechanical properties (fracture strength of over 600 MPa and fracture toughness of 12 MPa-m1/2). In this paper, microstructure and fractography of B4C-Al cermets, tested under dynamic and static loading conditions, are described.The cermet is prepared by infiltration of Al at 1150°C into partially sintered B4C compact under vacuum to full density. Fracture surface replicas were prepared by using cellulose acetate and thin-film carbon deposition. Samples were observed with a Philips 3000 at 100 kV.

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CREDO RADON UA – INFORMATION MODEL FOR CALCULATION OF ROAD CONSTRACTION

Avtoshliakhovyk Ukrayiny ◽

10.33868/0365-8392-2019-3-259-34-42 ◽

2019 ◽

pp. 34-42

Author(s):

Volodymyr Karedin ◽

Nadiya Pavlenko

Keyword(s):

Design Process ◽

Static Loading ◽

Computer Aided Design ◽

Experimental Studies ◽

Construction Materials ◽

Residual Deformation ◽

Road Construction ◽

Information Support ◽

Existing Structures ◽

Road Pavement

CREDO RADON UA software provides an automated calculation of the strength of the pavement structures of non-rigid and rigid types, as well as the calculation of the strengthening of existing structures. In the article, one can see the main features and functionality of the CREDO RADON UA software, the main points in the calculations according to the new regulations. Information support of the design process includes necessary databases, informational and helping materials that make up the full support of the pavement design process. The concept of CREDO RADON UA 1.0 software is made on the use of elasticity theory methods in calculations of initial information models of pavements. Performing optimization calculations, the roadwear in CREDO RADON UA is designed in such a way that no unacceptable residual deformation occurs under the influence of short-term dynamic or static loading in the working layer of the earth bed and in the structural layers during the lifetime of the structure. The calculation algorithms were made in accordance with the current regulatory documents of Ukraine. CREDO RADON UA software allows user to create information bases on road construction materials and vehicles as part of the traffic flow for calculations. The presented system of automated modeling makes it easier for the customer to control the quality of design solutions, to reasonably assign designs to layers of reinforcement, to quickly make comparisons of calculations of different designs for the optimal use of allocated funds. Prospects for further improvement of the program should be the results of theoretical and experimental studies on filling the databases, which are used as information support for automated design of road structures. Keywords: CREDO RADON UA, road, computer-aided design, repair project, road pavement, strengthening, construction, rigid pavement, elasticity module, a transport stream, calculation method, information support, dynamic or static loading.

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Behavior of composite shells under transverse impact and quasi-static loading

AIAA Journal ◽

10.2514/3.13934 ◽

1998 ◽

Vol 36 ◽

pp. 1065-1073

Author(s):

Brian L. Wardle ◽

Paul A. Lagace

Keyword(s):

Static Loading ◽

Composite Shells ◽

Transverse Impact

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Development of Experimental P-Y Curves from Centrifuge Tests for Piles Subjected to Static Loading and Liquefaction-Induced Lateral Spreading

DFI Journal The Journal of the Deep Foundations Institute ◽

10.37308/dfijnl.20191120.212 ◽

2020 ◽

Vol 14 (1) ◽

Author(s):

Milad Souri

Keyword(s):

Static Loading ◽

Pore Water Pressure ◽

Water Pressure ◽

Pressure Ratio ◽

Lateral Spreading ◽

American Petroleum Institute ◽

Unique Contribution ◽

Pile Groups ◽

Centrifuge Tests ◽

Centrifuge Models

The results of five centrifuge models were used to evaluate the response of pile-supported wharves subjected to inertial and liquefaction-induced lateral spreading loads. The centrifuge models contained pile groups that were embedded in rockfill dikes over layers of loose to dense sand and were shaken by a series of ground motions. The p-y curves were back-calculated for both dynamic and static loading from centrifuge data and were compared against commonly used American Petroleum Institute p-y relationships. It was found that liquefaction in loose sand resulted in a significant reduction in ultimate soil resistance. It was also found that incorporating p-multipliers that are proportional to the pore water pressure ratio in granular materials is adequate for estimating pile demands in pseudo-static analysis. The unique contribution of this study is that the piles in these tests were subjected to combined effects of inertial loads from the superstructure and kinematic loads from liquefaction-induced lateral spreading.

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