Effect of Applied Compressive Stress and Impregnation Material on Internal Strain and Stress State in Nb3Sn Rutherford Cable Stacks

Development of internal damage within resin composites was evaluated under compressive loading in order to predict crack initiation and fracture. Moreover, three-point bending tests were also carried out in order to clarify mechanical behavior and fracture under tensile stress state in comparison with those under compressive stress state. Both of them were conducted for the purpose of obtaining data to formulate constitutive equations for resin composites and to implement precise numerical simulation. Columnar specimens for compression tests and square pole specimens for three-point bending tests were prepared by using clinical resin composites. In compression tests, loading–unloading (or –reloading) was given to columnar specimens and Young’s modulus was evaluated by the gradient of stress–strain curves under unloading. Internal damage was evaluated from the variation of Young’s modulus as a scalar damage variable based on the continuum damage mechanics. The variation of apparent density and residual strain at vanished stress were also discussed in association with the development of internal damage. Accumulation of internal damage was found on the stress–strain curve under loading–unloading–reloading in comparison with the curve under monotonic loading. On the other hand, in three-point bending tests, dependence of stress–strain curves on light curing time and strain rate was clarified. Since compression tests have been carried out under similar experimental conditions by authors so far, mechanical behaviors of resin composites under tensile stress state were discussed in comparison with those under compressive stress state. Brittleness under tensile stress state was indicated in comparison with compressive stress state.

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Herringbone Buckling Patterns of Compressed Thin Films on Compliant Substrates

Journal of Applied Mechanics ◽

10.1115/1.1756141 ◽

2004 ◽

Vol 71 (5) ◽

pp. 597-603 ◽

Cited By ~ 403

Author(s):

X. Chen ◽

John W. Hutchinson

Keyword(s):

Thin Films ◽

Thermal Expansion ◽

Stress State ◽

Compressive Stress ◽

Critical Stress ◽

Metal Film ◽

Minimum Energy ◽

Thin Metal Film ◽

Thermal Expansion Mismatch ◽

Compliant Substrates

A thin metal film vapor deposited on thick elastomer substrate develops an equi-biaxial compressive stress state when the system is cooled due to the large thermal expansion mismatch between the elastomer and the metal. At a critical stress, the film undergoes buckling into a family of modes with short wavelengths characteristic of a thin plate on a compliant elastic foundation. As the system is further cooled, a highly ordered herringbone pattern has been observed to develop. Here it is shown that the herringbone mode constitutes a minimum energy configuration among a limited set of competing modes.

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Application of acoustoelasticity in studying compressive stress state in Polymer bonded explosive

2015 IEEE Far East NDT New Technology & Application Forum (FENDT) ◽

10.1109/fendt.2015.7398318 ◽

2015 ◽

Author(s):

Yao Xu ◽

Zhan-feng Yang ◽

Hai-qiang Zhou ◽

Wei-bin Zhang

Keyword(s):

Stress State ◽

Compressive Stress

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Effects of initial stress state on the subsurface stress distribution after ultrasonic impact treatment on thick specimens

The Journal of Strain Analysis for Engineering Design ◽

10.1177/0309324720976837 ◽

2020 ◽

pp. 030932472097683

Author(s):

Chuan Liu ◽

Jiabin Shen ◽

Changhua Lin ◽

Jianfei Wang ◽

Jianxin Wang

Keyword(s):

Stress State ◽

Stress Distribution ◽

Tensile Stress ◽

Compressive Stress ◽

Initial Stress ◽

Correction Method ◽

Welding Residual Stress ◽

Initial Stress State ◽

Ultrasonic Impact Treatment ◽

Before And After

Thick welded specimens with different initial stress states were prepared and treated with the ultrasonic impact treatment (UIT). The subsurface stresses before and after UIT were measured by the X-ray diffraction (XRD) method combined with layer removal. The measured results were corrected based on the finite element correction method. The effects of initial high tensile stress and low compressive stress on the in-depth after-UIT stress distributions were investigated. The results show that initial stress has no effects on the stresses induced by the UIT within 1 mm depth and within that depth, UIT can induce almost the same longitudinal and transverse stress curves beneath the surface with a peak compressive stress close to the material yield strength at the depth of near 0.6 mm and 0.8 mm. UIT induces almost the same longitudinal and transverse stresses along with the measured depth under initial low compressive stress state. While under the initial high tensile stress state, the initial stress dominates the final stress distribution over 1 mm depth. Initial high tensile stress (welding residual stress) can reduce the depth of the after-UIT compressive stresses to 62.5% to 75% of that under the initial low-compressive stress state.

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Effects of pile material and loading state on adhesive strength of piles in ice

Canadian Geotechnical Journal ◽

10.1139/t83-075 ◽

1983 ◽

Vol 20 (4) ◽

pp. 673-680 ◽

Cited By ~ 2

Author(s):

R. Frederking ◽

J. Karri

Keyword(s):

Stress State ◽

Compressive Stress ◽

Adhesive Strength ◽

Laboratory Tests ◽

Test Series ◽

Coated Steel ◽

Special Test ◽

Relative Stiffness ◽

Concrete Piles ◽

Stress States

Laboratory tests on piles made of different materials (polyethylene, polyvinylchloride, steel, wood, concrete, and Inerta 160-coated steel) were used to investigate their adhesion to an ice cover at high rates of loading. Steel, wood, and concrete piles had adhesive strengths from 0.4 to 0.5 MPa; failure at these stresses occurred in the ice. Polyethylene and polyvinylchloride piles had an adhesive strength in the range 0.05–0.07 MPa; failure was characterized by separation between the pile and the ice. Inerta 160-coated steel had an intermediate strength of 0.25 MPa. Measured strengths were related both to the adhesion of ice to the pile and compliance of the pile. A special test series investigated the effect on adhesion of a tensile or compressive stress state in a polyethylene pile. An adhesive strength of 0.06 MPa was recorded in tension, and 0.13 MPa in compression, because of the relative stiffness of the pile and the ice. Keywords: ice loading, piles, ice adhesion, pile material, stress states.

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Effect of Top-Layer Thickness on Residual Stresses of Plasma-Spraying Sm2Zr2O7/YSZ Thermal Barrier Coatings

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.347-353.40 ◽

2011 ◽

Vol 347-353 ◽

pp. 40-43

Author(s):

Hong Song Zhang ◽

Hong Chan Sun ◽

Xiao Ge Chen

Keyword(s):

Stress State ◽

Layer Thickness ◽

Compressive Stress ◽

Plasma Spraying ◽

Thermal Barrier ◽

Bonding Layer ◽

Shear Stresses ◽

Horizontal Distance ◽

Barrier Coatings ◽

Layer Interface

In this paper, effect of top-layer thickness on residual stressess of plasma-spraying DCL coating of Sm2Zr2O7 and YSZ was studied by FEM. Results show that Radial stresses in DCL TBCs have similar distributions along horizontal distance which decrease gradually with increasing top-layer thickness. Radial stresses at YSZ layer/ bonding layer remians compressive stress state which is helpful to increase bonding strength the TBCs. Shear stresses transform gradually from tensile stress state to compressive stress state along horizontal distance, and they increase with increasing top-layer thickness. Axial stresses at top-layer/YSZ layer interface increase gradually with increasing top-layer thickness, however, axial stresses at YSZ layer/bonding layer interface were almost not effected by top-layer thickness.

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Measurement of all Six Components of X-Ray Elastic Factors

Materials Science Forum ◽

10.4028/www.scientific.net/msf.571-572.225 ◽

2008 ◽

Vol 571-572 ◽

pp. 225-229 ◽

Cited By ~ 3

Author(s):

Balder Ortner ◽

Thomas Antretter ◽

Michael Hofmann ◽

Ewald Werner

Keyword(s):

Stress State ◽

Compressive Stress ◽

Single Specimen ◽

X Ray ◽

Measurement Direction ◽

Set Up

A method is presented by which all components of Fij(ϕ, ψ, hkl) belonging to the same measurement direction and reflection can be determined. The neutron measurements are to be done with a single specimen, shaped as a cuboctahedron. An apparatus for producing a compressive stress state in the specimen is needed. It must be small enough to fit into the neutron goniometer and to allow movement of the goniometer to all Eulerian angles. Using this set-up the tensors F(ϕ, ψ, hkl) can be measured for any ϕ, ψ and (hkl).

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