A transversely hyperelastic constitutive model of flexible film composite

This paper presents a transversely hyperelastic constitutive model for predicting mechanical properties of flexible composites under unidirectional tension. A strain energy function which reflects the behavior of anisotropic elastic material is decomposed into three parts: matrix, fiber and fiber-matrix interaction. The fiber-matrix interaction was decomposed into in-plane shear stresses and out-of-plane shear stress, the in-plane shear stresses were related to the fiber elongation invariants, and the out-of-plane shear stress was related to the fiber elongation invariants and the matrix invariants. The fiber-matrix interaction considering shear factor was established. Based on fiber reinforced continuum mechanics, a transverse hyperelastic constitutive model including fiber, matrix and their interaction is developed. The transversely hyperelastic constitutive model is verified by the uniaxial tension tests. The constitutive model can be used to design the flexible structure of stratospheric airship.

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Effect of Residual Shear Stresses on Released Strains in Isotopic and Orthotropic Materials Measured by the Slitting Method

Journal of Engineering Materials and Technology ◽

10.1115/1.4005267 ◽

2011 ◽

Vol 134 (1) ◽

Cited By ~ 6

Author(s):

Mahmood M. Shokrieh ◽

Saeed Akbari R.

Keyword(s):

Shear Stress ◽

Normal Stress ◽

Surface Strain ◽

Strain Gauges ◽

Orthotropic Materials ◽

Back Surface ◽

Shear Stresses ◽

Plane Shear ◽

Slitting Method ◽

Out Of Plane

This paper investigates the effect of shear stresses on the determination of residual stresses in isotropic and orthotropic materials by the slitting method. A great deal of research effort is focused on the estimation of the residual stress component normal to the slit face using strain data measured by strain gauges installed on the top or the back surface of the stressed specimens. However, the slitting process will also release two in-plane and out-of-plane shear stress components, which may influence the measured strains. For the two specimens of carbon/epoxy and glass/epoxy laminated composites as well as a steel specimen, the distribution of released strains on the top and the back surfaces due to the shear stresses is calculated using finite element method and compared with those due to the residual normal stress. The results show that on the back surface, the shear stresses have a very small effect on the measured strains. However, on the top surface, strains due to the residual shear stresses are significant compared with those due to the residual normal stress and cannot be ignored. A method using two top surface strain gauges in both sides of the slit is presented to separate the effects of normal and shear stresses from each other. Also, strains due to the in-plane and the out-of-plane shear stresses could be isolated from each other. If these separations could be carried out successfully, the residual shear stress can be calculated by the proposed formulation.

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Finite Element Analysis of Tire/Rim Interface Forces Under Braking and Cornering Loads

Tire Science and Technology ◽

10.2346/1.2139512 ◽

1992 ◽

Vol 20 (2) ◽

pp. 83-105 ◽

Cited By ~ 5

Author(s):

J. P. Jeusette ◽

M. Theves

Keyword(s):

Finite Element ◽

Shear Stress ◽

Contact Pressure ◽

Element Model ◽

Shear Stresses ◽

Detailed Knowledge ◽

Stress Distributions ◽

Element Analysis ◽

Plane Shear ◽

Normal Contact

Abstract During vehicle braking and cornering, the tire's footprint region may see high normal contact pressures and in-plane shear stresses. The corresponding resultant forces and moments are transferred to the wheel. The optimal design of the tire bead area and the wheel requires a detailed knowledge of the contact pressure and shear stress distributions at the tire/rim interface. In this study, the forces and moments obtained from the simulation of a vehicle in stationary braking/cornering conditions are applied to a quasi-static braking/cornering tire finite element model. Detailed contact pressure and shear stress distributions at the tire/rim interface are computed for heavy braking and cornering maneuvers.

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Fundamental Solutions of Two-Dimensional In-Plane Problems and Out-of-Plane Shear Problems for Cylindrically Anisotropic Elastic Medium.

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series A ◽

10.1299/kikaia.64.80 ◽

1998 ◽

Vol 64 (617) ◽

pp. 80-86

Author(s):

Kenichi HIRASHIMA ◽

Shini NI

Keyword(s):

Elastic Medium ◽

Fundamental Solutions ◽

Two Dimensional ◽

Anisotropic Elastic Medium ◽

Plane Shear ◽

Out Of Plane ◽

Anisotropic Elastic ◽

Cylindrically Anisotropic

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Steel Sheet Shear Walls with Burring Holes for Low- to Mid-Rise Housings

IABSE Congress, New York, New York 2019: The Evolving Metropolis ◽

10.2749/newyork.2019.2780 ◽

2019 ◽

Author(s):

Yoshimichi Kawai ◽

Shigeaki Tohnai ◽

Shinichiro Hashimoto ◽

Atsushi Sato ◽

Tetsuro Ono

Keyword(s):

Finite Element ◽

Shear Stress ◽

Large Deformation ◽

Deformation Behavior ◽

Steel Sheet ◽

Shear Walls ◽

Shear Load ◽

Finite Element Analyses ◽

Plane Shear ◽

Out Of Plane

<p>Steel sheet shear walls with cold formed edge stiffened burring holes are applied to low- to mid-rise housings in seismically active and typhoon- or hurricane-prone regions. A configuration with burrs on the inside and smooth on the outside enables the construction of omitting the machining of holes for equipments and thinner walls with simplified attachments of finishings. In-plane shear experiments and finite element analyses revealed that the walls allowed shear stress to concentrate in intervals between the burring holes. The walls maintained stable shear load and large deformation behavior, and the deformation areas were limited in the intervals and a large out-of-plane waveform in a sheet was effectively prevented owing to edge stiffened burring ribs. The design methods are developed for evaluating the shear load of the walls at story angle from zero to 1/100, using the idea of decreasing the band width of the inclined tension fields on the intervals with the effects of the thickness.</p>

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Mechanics of Cell Mechanosensing on Patterned Substrate

Journal of Applied Mechanics ◽

10.1115/1.4032907 ◽

2016 ◽

Vol 83 (5) ◽

Cited By ~ 11

Author(s):

Chenglin Liu ◽

Shijie He ◽

Xiaojun Li ◽

Bo Huo ◽

Baohua Ji

Keyword(s):

Shear Stress ◽

Principal Stress ◽

Maximum Shear Stress ◽

Cell Monolayer ◽

Maximum Principal Stress ◽

Mechanical Force ◽

Shear Stresses ◽

Plane Shear ◽

Cell Behaviors ◽

Mechanical Signals

It has been recognized that cells are able to actively sense and respond to the mechanical signals through an orchestration of many subcellular processes, such as cytoskeleton remodeling, nucleus reorientation, and polarization. However, the underlying mechanisms that regulate these behaviors are largely elusive; in particular, the quantitative understanding of these mechanical responses is lacking. In this study, combining experimental measurement and theoretical modeling, we studied the effects of rigidity and pattern geometry of substrate on collective cell behaviors. We showed that the mechanical force took pivotal roles in regulating the alignment and polarization of cells and subcellular structures. The cell, cytoskeleton, and nucleus preferred to align and polarize along the direction of maximum principal stress in cell monolayer, and the driving force is the in-plane maximum shear stress. The higher the maximum shear stress, the more the cells and their subcellular structures preferred to align and polarize along the direction of maximum principal stress. In addition, we proved that in response to the change of in-plane shear stresses, the actin cytoskeleton is more sensitive than the nucleus. This work provides important insights into the mechanisms of cellular and subcellular responses to mechanical signals. And it also suggests that the mechanical force does matter in cell behaviors, and quantitative studies through mechanical modeling are indispensable in biomedical and tissue engineering applications.

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