Stress Distribution in an Infinite Elastic Medium Containing four Non-Intersecting Griffith Cracks

1. In this paper an analysis is given of the distribution of stress in a semi-infinite elastic medium due to the action of an external force applied to the interior of the medium. It will be assumed throughout that the force acts in a direction perpendicular to that of the boundary of the solid; the analysis is similar when the line of action of the force is parallel to the boundary and is therefore not given here. The equations of plane strain parallel to the x-y plane are employed; physically this is equivalent to assuming that there is no component of the displacement vector in a direction normal to the x-y plane or, what is the same thing, that the external force is applied along are infinite line parallel to the axis of z.

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Analysis of Disturbing Influence of Traffic Load on Soil Body

Advances in Materials Science and Engineering ◽

10.1155/2015/318289 ◽

2015 ◽

Vol 2015 ◽

pp. 1-7 ◽

Cited By ~ 5

Author(s):

Janat Musayev ◽

Algazy Zhauyt

Keyword(s):

Stress Distribution ◽

Elastic Medium ◽

Traffic Flow ◽

Stress Waves ◽

Point Sources ◽

Traffic Load ◽

Strength Evaluation ◽

Propagating Waves ◽

Waves Propagation ◽

Distribution Of Stress

Stress waves propagate in soil in case of earthquake and man-made effects (traffic flow, buried explosions, shield-driven pipes and tunnels, etc.). The wave point-sources are those located at the distances equal to more than two waves lengths, which significantly simplifies solving of a problem of these waves’ strength evaluation. Distribution of stress and displacement by the stress waves propagation in elastic medium is a complex pattern. The stress distribution in propagating waves depends on the type and form of source, conditions of the source contact with medium, and properties of mediums in the vicinity of the source. The point-sources and their combinations are selected in such a way to model an influence of machines and processes on soil body in case of shield-driven pipes (tunnels).

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The concerted use of SEM, TEM, and SCM for examination of resin-dentin interfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100170116 ◽

1994 ◽

Vol 52 ◽

pp. 476-477

Author(s):

B. Van Meerbeek ◽

L. J. Conn ◽

E. S. Duke

Keyword(s):

Surface Layer ◽

Stress Distribution ◽

Phosphoric Acid ◽

Bonding Mechanism ◽

Restorative Dentistry ◽

Dental Adhesive ◽

Low Viscosity ◽

Dentin Adhesives ◽

Acid Etch ◽

Tooth Tissue

Restoration of decayed teeth with tooth-colored materials that can be bonded to tooth tissue has been a highly desirable property in restorative dentistry for many years. Advantages of such an adhesive restorative technique over conventional techniques using non-adhesive metal-based restoratives include improved restoration retention with minimal sacrifice of sound tooth tissue for retention purposes, superior adaptation and sealing of the restoration margins in prevention of caries recurrence, improved stress distribution across the tooth-restoration interface throughout the whole tooth, and even reinforcement of weakened tooth structures. The dental adhesive technology is rapidly changing. An efficient resin bond to enamel has already long been achieved. Its bonding mechanism has been fully elucidated and has proven to be a durable and reliable clinical treatment. However, bonding to dentin represents a greater challenge. After the failures of a dentin acid-etch technique in imitation of the enamel phosphoric-acid-etch technique and a bonding procedure based on chemical adhesion, modern dentin adhesives are currently believed to bond to dentin by a micromechanical hybridization process. This process is developed by an initial demineralization of the dentin surface layer with acid etchants exposing a collagen fibril arrangement with interfibrillar microporosities that subsequently become impregnated by low-viscosity monomers. Although the development of such a hybridization process has well been documented in the literature, questions remain with respect to parameters of-primary importance to adhesive efficacy.

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