A modified Kolsky method for determining the shear strength of brittle materials

An experimental study of the dynamic properties of fine-grained concrete under tensile and shear stresses has been carried out. A comprehensive study of the dynamic properties of concrete allows obtaining experimental data and constants. These data and constants are needed to equip dynamic strain and fracture models. The system of experiments is based on modifications of the Kolsky method. This system of experiments allows one to determine a wide range of strength and time characteristics of concrete under shock loading. The experimental setup according to the Kolsky method includes a system of measuring rods between which a test sample is installed, a gas gun for accelerating a cylindrical striker, strain gauges, a speed meter, recording and computing equipment with a software package. Conducted dynamic tests of concrete in a wide range of deformation rates (102–104 s–1). In experiments on direct tension and to determine the ultimate tensile stress of fine-grained concrete during splitting, two speed modes are implemented. In tests of shear strength, a modification of the Hopkinson split bar method was used to determine the dynamic shear strength, in which a sample made of the material under study is located in a rigid holder cut at an angle to the sample axis. The pulse recorded in the reference dipstick is used to plot the shear stress in the sample over time. Shear tests were carried out for three speeds. The results of the performed experiments on tensile, splitting and shearing are presented in the form of diagrams of stress versus deformation and stress versus time. The obtained characteristics can be used to equip computational experiments in the study of the strength of concrete structures subjected to dynamic influences.

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Use of the Kolsky method for dynamic tests of brittle media

MATEC Web of Conferences ◽

10.1051/matecconf/201817402022 ◽

2018 ◽

Vol 174 ◽

pp. 02022 ◽

Cited By ~ 1

Author(s):

Anatoliy Bragov ◽

Leonid Igumnov ◽

Andrey Lomunov ◽

Alexander Konstantinov ◽

Dmitriy Lamzin ◽

...

Keyword(s):

Split Hopkinson Pressure Bar ◽

Dynamic Test ◽

Brittle Materials ◽

Fiber Reinforced Concrete ◽

Dynamic Tests ◽

Hopkinson Pressure Bar ◽

Kolsky Method ◽

Indirect Tension ◽

Split Hopkinson ◽

Pressure Bar

The dynamic test techniques used to obtain the mechanical properties of brittle materials are described. The techniques are based on the fundamental Kolsky method using the Split-Hopkinson Pressure Bar. Dynamic tests are characterized by high intensity and short duration and the influence of inertia on their results should be ruled out which is especially important for brittle media. The prerequisites and assumptions presented methods are described to justify the validity of the obtained data. The methods allow to obtain dynamic deformation diagrams at compression, splitting, indirect tension, shear and triaxial stress state and also to determine the ultimate strength, strain and time properties of brittle materials. The techniques are approved in the tests of ceramic bricks, finegrain concrete and fiber-reinforced concrete.

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Application of TEM to Deformation, Wear, and Fracture of Ceramics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052377 ◽

1974 ◽

Vol 32 ◽

pp. 472-473

Author(s):

B. J. Hockey

Keyword(s):

Wear Resistance ◽

High Temperature ◽

Mechanical Behavior ◽

Brittle Materials ◽

High Temperature Strength ◽

Wide Range ◽

Corrosive Environments ◽

Further Development

Ceramics, such as Al2O3 and SiC have numerous current and potential uses in applications where high temperature strength, hardness, and wear resistance are required often in corrosive environments. These materials are, however, highly anisotropic and brittle, so that their mechanical behavior is often unpredictable. The further development of these materials will require a better understanding of the basic mechanisms controlling deformation, wear, and fracture.The purpose of this talk is to describe applications of TEM to the study of the deformation, wear, and fracture of Al2O3. Similar studies are currently being conducted on SiC and the techniques involved should be applicable to a wide range of hard, brittle materials.

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Failure wave as resonance excitation of collective burst modes of defects in shocked brittle materials

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:20009134 ◽

2000 ◽

Vol 10 (PR9) ◽

pp. Pr9-811-Pr9-816 ◽

Cited By ~ 2

Author(s):

O. A. Plekhov ◽

D. N. Eremeev ◽

O. B. Naimark

Keyword(s):

Brittle Materials ◽

Resonance Excitation ◽

Failure Wave

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Holding Power of Orthopaedic Screws in Metacarpal and Metatarsal Bones of Young Calves

Veterinary and Comparative Orthopaedics and Traumatology ◽

10.1055/s-0038-1633077 ◽

1992 ◽

Vol 05 (03) ◽

pp. 100-103 ◽

Cited By ~ 4

Author(s):

G. Jean ◽

J. K. Roush ◽

R. M. DeBowes ◽

E. M. Gaughan ◽

J. Kirpensteijn

Keyword(s):

Shear Strength ◽

Tensile Load ◽

Young Female ◽

Limiting Factor ◽

Holding Power ◽

Metatarsal Bones ◽

Bone Width ◽

Load To Failure ◽

Holstein Calves

SummaryThe holding power and holding power per mm bone width of 4.5 mm and 5.5 mm cortical and 6.5 mm cancellous orthopaedic screws were obtained by tensile load-to-failure studies in excised metacarpal and metatarsal bones of young female Holstein calves. Holding power and holding power per mm bone width of 6.5 mm orthopaedic screws were significantly greater than those of 4.5 and 5.5 mm orthopaedic screws in the diaphysis and metaphysis. Significant differences were not detected between holding power and holding power per mm bone width of 4.5 and 5.5 mm orthopaedic screws. The holding power was not different between metacarpi and metatarsi. The limiting factor in all tests of holding power was the shear strength of the bone. We found that 6.5 mm orthopaedic screws have the greatest holding power in the metacarpal and metatarsal bones of young calves.This study compares the holding power of 4.5 mm and 5.5 mm cortical and 6.5 mm cancellous orthopaedic screws in excised metacarpal and metatarsal bones from young female Holstein calves. We found that 6.5 mm orthopaedic screws have the greatest holding power.

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The Fully Softened Shear Strength of Lake Agassiz Clays

Geo-Congress 2020 ◽

10.1061/9780784482797.018 ◽

2020 ◽

Author(s):

Iván A. Contreras ◽

Jed D. Greenwood ◽

Aaron T. Grosser

Keyword(s):

Shear Strength ◽

Lake Agassiz ◽

Fully Softened Shear Strength

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Influence of anatomy on the adhesion performance of four wood species

Research Society and Development ◽

10.33448/rsd-v9i4.2727 ◽

2020 ◽

Vol 9 (4) ◽

pp. e31942727

Author(s):

João Gabriel Missia da Silva ◽

Pedro Nicó de Medeiros ◽

Denise Ransolin Soranso ◽

Vinicius Peixoto Tinti ◽

José Tarcísio da Silva Oliveira ◽

...

Keyword(s):

Shear Strength ◽

Specific Gravity ◽

Wood Species ◽

Tectona Grandis ◽

Glue Line ◽

Anatomical Characteristics ◽

Ray Cells ◽

Adhesion Performance ◽

Adhesion Process

The aim of this study was to evaluate the influence of anatomical characteristics on the adhesion performance of Vatairea sp., Paulownia sp., Aspidosperma populifolium and Tectona grandis wood. Specimens for anatomical, physical and mechanical analyzes were produced from tangentially oriented boards. The treatments were joint glued from pieces of the same anatomical orientation (radial and tangential), evaluated for shear strength and glue line failure. The Vatairea sp wood had the highest specific gravity (0.74 g cm-3) and the Paulownia sp (0.34 g cm-3) wood was smaller. Aspidosperma populifolium species showed the highest shear strength in the glue line in the tangential and radial faces. The anatomical variables with higher influence on the wood adhesion process were pith ray cells and especially fibers that exhibit the greatest correlation with the shear strength of the glue line.

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