Viscous interfaces as source for material creep: A continuum micromechanics approach

Shahidi, M.; Pichler, Bernhard; Hellmich, C.

doi:10.1016/j.euromechsol.2013.11.001

Cited by 48 publications

(48 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This review comprises both types of so-called Hashin boundary conditions [17], i.e., uniform strain boundary conditions and uniform stress boundary conditions, as means for the study of relaxation and creep properties, respectively. The latter properties are comparatively simple to be derived from the microscopic interface behavior, and the corresponding result can be directly recalled from our previous study [15]. The derivation of relaxation functions turns out as formidable mathematical task, which Sect.…”

Section: Introductionmentioning

confidence: 99%

“…The interfaces are considered to host fluids adsorbed to electrically charged solid surfaces [15]. Accordingly, the polar fluid molecules (such as water) build up layers, i.e., such fluids are in a "glassy" or "liquid crystal" state, right in between the long-range positional and orientational order found in solids and the long-range disorder found in liquids.…”

Section: Matrix-interface Micromechanics For Different Interface Famimentioning

confidence: 99%

“…The latter idea was recently elaborated in the framework of continuum micromechanics [15], based on eigenstress homogenization schemes [16]. Extending the analysis of [15]-where we mainly focused on identical interfaces-we here consider interaction among two classes of interfaces (referred to as "interface families"), differing in interface size, viscosity, and density. The theoretical basis for our analysis is the topic of Sect.…”

Section: Introductionmentioning

confidence: 99%

“…The theoretical basis for our analysis is the topic of Sect. 2, where we briefly recall fundamental state equations governing the time-dependent behavior of matrix-interface composites comprising two-dimensional interfaces filled with viscous fluids [15]. This review comprises both types of so-called Hashin boundary conditions [17], i.e., uniform strain boundary conditions and uniform stress boundary conditions, as means for the study of relaxation and creep properties, respectively.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

How interface size, density, and viscosity affect creep and relaxation functions of matrix-interface composites: a micromechanical study

2015

View full text Add to dashboard Cite

Matrix-inclusion composites are known to exhibit interaction among the inclusions. When it comes to the special case of inclusions in form of flat interfaces, interaction among interfaces would be clearly expected, but the two-dimensional nature of interfaces implies quite surprising interaction properties. This is the motivation to analyze how interaction among two different classes of microscopic interfaces manifests itself in macroscopic creep and relaxation functions of matrix-interface composites. To this end, we analyze composites made of a linear elastic solid matrix hosting parallel interfaces, and we consider that creep and relaxation of such composites result from micro-sliding within adsorbed fluid layers filling the interfaces. The latter idea was recently elaborated in the framework of continuum micromechanics, exploiting eigenstress homogenization schemes, see Shahidi et al. (Eur J Mech A Solids 45:41-58, 2014). After a rather simple mathematical exercise, it becomes obvious that creep functions do not reflect any interface interaction. Mathematical derivation of relaxation functions, however, turns out to be much more challenging because of pronounced interface interaction. Based on a careful selection of solution methods, including Laplace transforms and the method of non-dimensionalization, we analytically derive a closed-form expression of the relaxation functions, which provides the sought insight into interface interaction. The seeming paradox that no interface interaction can be identified from creep functions, while interface interaction manifests itself very clearly in the relaxation functions of matrix-interface materials, is finally resolved based on stress and strain average rules for interfaced composites. They clarify that uniform stress boundary conditions lead to a direct external control of average stress and strain states in the solid matrix, and this prevents interaction among interfaces. Under uniform strain boundary conditions, in turn, interfacial dislocations do influence the average stress and strain states in the solid matrix, and this results in pronounced interface interaction.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Matrix-interface Micromechanics For Different Interface Famimentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

How interface size, density, and viscosity affect creep and relaxation functions of matrix-interface composites: a micromechanical study

2015

View full text Add to dashboard Cite

show abstract

“…Keeping in mind the prominent role of interfaces as discussed before, recent achievements in continuum micromechanics have allowed for upscaling the properties of two-dimensional interfaces embedded in three-dimensional (3D) matrices to homogenized 3D material properties. 28 The micro-interface properties, in turn, may then be accessible through molecular dynamics approaches focusing strongly on the interface problem, and leaving aside most of the 3D bulk problem. Qu et al outline such an approach in the fi nal contribution in this issue.…”

Section: "Drowning In Complexity" Versus the Quest For A Unifying Picmentioning

confidence: 99%

Multiscale mechanics of biological, bioinspired, and biomedical materials

Hellmich

Katti

2015

MRS Bull.

View full text Add to dashboard Cite

Measuring mechanical properties is an integral part of almost any characterization procedure in state-of-the-art materials science. Such measurements are typically done according to standardized protocols, 1 , 2 both for equipment characteristics and data evaluation. These protocols have their origins in metallurgy, as well as mechanical and civil engineeringmetals being the fi rst materials used on a broad industrial scale. Over the course of time, the same or similar protocols were used for other materials, and recent decades have evidenced a growing interest in applying them to either biological materials or materials mimicking or replacing biological tissue.An immediate outcome of these activities was that the mechanical properties of biological materials were found to be highly variable and diffi cult to capture by the aforementioned protocols. One thought was that the mechanical theories underlying the testing protocols emanating from the metals fi eld might not be fully applicable to the highly complex, hierarchically organized biological materials and might need further development, and the corresponding basic assumptions may need to be rethought and improved. These developments, driven by the applied physics and chemistry communities, as well as the mechanical and civil engineering communities, have left their traces in these various scientifi c fi elds and refl ected back on materials science at large. This is illustrated by the various and ever-growing symposia at Materials Research Society (MRS) Meetings and other conferences over the last decade.This issue of MRS Bulletin is a compilation of articles highlighting different, complementary, and interdependent approaches to the challenge of extending theoretical and applied mechanics to the level needed for reliably capturing the properties of biological materials. The articles also include analogous, extensive consequences for measurement methods and evaluation protocols intended to determine mechanical procedures. Improving evaluation protocols: From stress-strain curves to elaborate back-analysis schemes founded on mechanical principlesProblems with proper determination of elastic properties of biological materials and biomaterials might start with basic and seemingly well-understood quantities such as Young's modulus. As one standard measure of elastic material behavior, Young's modulus can be determined from the linear portion of loading in a load-displacement curve obtained from quasistatic tests; this is in case the tested material exhibits a pronounced purely elastic regime, as is normally encountered Multiscale mechanics of biological, bioinspired, and biomedical materials Christian Hellmich and Dinesh Katti , Guest EditorsMechanical property measurement protocols have their origins in metallurgy as well as in mechanical and civil engineering-metals being the fi rst materials used on a broad industrial scale. Recent decades have evidenced growing interest in applying these protocols to biological materials or materials mimicking or replacing b...

show abstract

Uncertainty analysis of the power law extrapolation techniques for adhesive anchors

Podroužek

Wan‐Wendner

2018

Structural Concrete

View full text Add to dashboard Cite

Modern construction industry is increasingly utilizing postinstalled adhesive anchors as an alternative to traditional mechanical anchors. Although the application of adhesive anchors under sustained load offers many advantages, the associated approval guidelines based on a power law extrapolation technique have a number of ambiguities and limitations, which are shortly reviewed in this paper and subjected to uncertainty quantification and sensitivity analyses. Some of the observations presented may be considered as specific to the available experimental database of sustained load test, while some recommendations are universal, as they relate to the underlying creep phenomena and robust measures in regression. It is further shown, how a regression based safety factor could be derived from an experimental database and a possibilistic set of plausible choices.

show abstract

Viscous interfaces as source for material creep: A continuum micromechanics approach

Cited by 48 publications

References 40 publications

How interface size, density, and viscosity affect creep and relaxation functions of matrix-interface composites: a micromechanical study

How interface size, density, and viscosity affect creep and relaxation functions of matrix-interface composites: a micromechanical study

Multiscale mechanics of biological, bioinspired, and biomedical materials

Uncertainty analysis of the power law extrapolation techniques for adhesive anchors

Contact Info

Product

Resources

About