Non-symmetric stiffness tensor prediction by the Mori–Tanaka scheme – Comments on the article “Effective anisotropic stiffness of inclusions with debonded interface for Eshelby-based models” [Composite Structures 131 (2015) 692–706]

5. From Group or Phase Velocities to the General Anisotropic Stiffness Tensor

Seismic Anisotropy ◽

10.1190/1.9781560802693.ch5 ◽

1996 ◽

pp. 101-140 ◽

Cited By ~ 5

Author(s):

Robert W. Vestrum ◽

R. James Brown ◽

Donald T. Easley

Keyword(s):

Stiffness Tensor ◽

Phase Velocities ◽

Anisotropic Stiffness

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Finite Element Analysis of Mechanical Properties of 2.5D Woven Composites

Materials Science Forum ◽

10.4028/www.scientific.net/msf.950.175 ◽

2019 ◽

Vol 950 ◽

pp. 175-179

Author(s):

Fang Bin Lin ◽

Gen Wei Wang

Keyword(s):

Present Method ◽

Periodic Boundary ◽

Periodic Boundary Conditions ◽

Tensile Tests ◽

Volume Element ◽

Woven Composites ◽

Stiffness Tensor ◽

Element Analysis ◽

Static Tensile ◽

Anisotropic Stiffness

It is calculated the effective anisotropic stiffness tensor of the representative volume element in 2.5D woven composites by energy method. The Multi-point constraints are applied to periodic boundary conditions. Compared with the static tensile tests, the validity of present method is verified.

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Effective anisotropic stiffness of inclusions with debonded interface for Eshelby-based models

Composite Structures ◽

10.1016/j.compstruct.2015.06.007 ◽

2015 ◽

Vol 131 ◽

pp. 692-706 ◽

Cited By ~ 21

Author(s):

Atul Jain ◽

Yasmine Abdin ◽

Wim Van Paepegem ◽

Ignaas Verpoest ◽

Stepan V. Lomov

Keyword(s):

Debonded Interface ◽

Anisotropic Stiffness

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An efficient algorithm for computing nearest medium approximations to an arbitrary anisotropic stiffness tensor

Geophysics ◽

10.1190/geo2013-0388.1 ◽

2014 ◽

Vol 79 (3) ◽

pp. C81-C90 ◽

Cited By ~ 12

Author(s):

Lennert D. den Boer

Keyword(s):

Large Field ◽

Stiffness Tensor ◽

Fracture Networks ◽

Field Scale ◽

Higher Symmetry ◽

Discrete Fracture Networks ◽

Discrete Fracture ◽

Transverse Isotropic ◽

Problem Instances ◽

Anisotropic Stiffness

The problem of reducing a fully anisotropic (triclinic) stiffness tensor comprised of 21 distinct components to a higher symmetry form having fewer distinct elements is of interest in many geophysical applications, where assuming a particular type of symmetry is often necessary to sufficiently reduce computational complexity to allow practical solutions. In addition, recent advances in the upscaling of realistically large field-scale discrete fracture networks have led to the need for an efficient way to derive a very large number of nearest medium approximations to the triclinic stiffness tensors obtained. Owing to rotational symmetries and nonlinearity, the problem of efficiently finding such approximations is generally nontrivial because optimal orientations are intrinsically nonunique. An algorithm proposed by Dellinger computes nearest orthotropic and transverse isotropic approximations for a given stiffness tensor, using the Federov norm as an objective function to iteratively minimize the fit error. Although this method is appropriate for computing solutions to single problem instances, the implementation is too inefficient for production situations, where a very large number of invocations of the algorithm is required. The enhanced algorithm proposed here is accurate, efficient, and general, allowing nearest medium approximations to be determined for arbitrary symmetry types, including isotropic, cubic, transverse isotropic, orthotropic, and monoclinic.

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Energy-Based Debonding Model for Steel-Concrete Composite Structures

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.97-101.1705 ◽

2010 ◽

Vol 97-101 ◽

pp. 1705-1708

Author(s):

Xiao Zhao Wang ◽

Xin Sheng Song

Keyword(s):

Shear Stress ◽

Composite Structures ◽

Interfacial Shear Stress ◽

Interfacial Shear ◽

Softening Behavior ◽

Strength Based ◽

Constant Shear Stress ◽

Proper Definition ◽

Debonded Interface ◽

Definition Of

This paper present a energy-based modelling approches for interfacial debonding between steel and concrete. Steel-concrete composite structural member is considered as a generalized elastic body with both the applied load and the interfacial shear stress acting as boundary stresses, and the debonding is modeled as crack propagation along the interface. The energy relationship is discussed in the process of debonding and an energy-based criterion for steel-concrete composite structure is proposed. Following, the debonding process is analyzed through energy-based criterion. The analysis is first performed for special case with constant shear stress along debonded interface, and then for the general case with shear stress softening in the debonded zone. A direct correspondence between energy-based and strength-based analysis can be established for arbitrary softening behavior along the interface. Specifically, through the proper definition of effective interfacial shear strength, the conventional strength-based approach can be employed to give the same results as the much more complicated energy-based analysis.

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In Situ microscopy of the anodic etching of silicon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100137537 ◽

1995 ◽

Vol 53 ◽

pp. 232-233

Author(s):

Frances M. Ross ◽

Peter C. Searson

Keyword(s):

Composite Structures ◽

High Surface ◽

High Surface Area ◽

Chemical Properties ◽

Selective Etching ◽

Silicon On Insulator ◽

Second Phase ◽

Porous Layers ◽

New Class ◽

Porous Semiconductors

Porous semiconductors represent a relatively new class of materials formed by the selective etching of a single or polycrystalline substrate. Although porous silicon has received considerable attention due to its novel optical properties1, porous layers can be formed in other semiconductors such as GaAs and GaP. These materials are characterised by very high surface area and by electrical, optical and chemical properties that may differ considerably from bulk. The properties depend on the pore morphology, which can be controlled by adjusting the processing conditions and the dopant concentration. A number of novel structures can be fabricated using selective etching. For example, self-supporting membranes can be made by growing pores through a wafer, films with modulated pore structure can be fabricated by varying the applied potential during growth, composite structures can be prepared by depositing a second phase into the pores and silicon-on-insulator structures can be formed by oxidising a buried porous layer. In all these applications the ability to grow nanostructures controllably is critical.

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