MULTIAXIAL

Stitchbonded fabrics ate used in home furnishings, footwear, filtration, packaging, and coating. Machine widths ate in the 2-m range fabric weights range from about 75—250 g/m. A variation of stitchbonding is used to make multiaxial-layeted yam and yam-and-sheet stmctures for composite material reinforcement substrates. 

There are many different equipment options avaQable to suit specific product needs including continuous winders for pipe, multiaxis winders for pressure vessels, and simple lathe-type winders for tanks and large pipe. Specialty machines combine a chopped reinforcement with continuous fibers for tank walls and large-diameter pipe where both stiffness and tensQe strength are required. Textile braiders have also been adapted for use as continuous... 

The stored strain energy can also be determined for the general case of multiaxial stresses [1] and lattices of varying crystal structure and anisotropy. The latter could be important at interfaces where mode mixing can occur, or for fracture of rubber, where f/ is a function of the three stretch rations 1], A2 and A3, for example, via the Mooney-Rivlin equation, or suitable finite deformation strain energy functional. 

The simplified failure envelopes differ little from the concept of yield surfaces in the theory of plasticity. Both the failure envelopes (or surfaces) and the yield surfaces (or envelopes) represent the end of linear elastic behavior under a multiaxial stress state. The limits of linear elastic... 

G. P. Sendecky), A Brief Survey of Empirical Multiaxial Strength Criteria for Composites, In Composite Materials Testing and Design (Second Conference), H. T. Corten (Chairman), Anaheim, Caiifomia, 20-22 April 1971, ASTM STP 497, American Society for Testing and Materials, 1972, pp. 41-51. 

T. Hoshide, K. Kusuura. Life prediction by simulation of crack growth in notched components with different microstructures and under multiaxial fatigue. Fatigue Fract Eng Mater Struct 27 201, 1998. 

Much more has been published over the last 50 years concerning the crack growth approach" than the crack nucleation approach for rubber. Consequently, the crack growth approach enjoys a relatively more mature position than the crack nucleation approach. In recent years, the development of equivalence parameters that work in cases involving multiaxial loading has renewed interest in the crack nucleation approach. 

Due to the plane-specific namre of crack nucleation under multiaxial tests. Mars and Fatemi proposed the cracking energy density as an equivalence parameter that represents the portion of strain energy density available to be released as crack growth on a specific material plane. The form of the cracking energy density Wc is... 

In a recent study, Saintier et al. ° investigated the multiaxial effects on fatigue crack nucleation and growth in natural mbber. They found that the same mechanisms of decohesion and cavitation of inclusions that cause crack nucleation and crack growth in uniaxial experiments were responsible for the crack behavior in multiaxial experiments. They studied crack orientations for nonproportional multiaxial fatigue loadings and found them to be related to the direction of the maximum first principal stress of a cycle when material plane rotations are taken into account. This method accounts for material rotations in the analysis due to the displacement of planes associated with large strain conditions. 

Mars, W.V., Multiaxial fatigue of rubber, Ph.D. dissertation. The University of Toledo, Toledo, OH, 2001. 

Saintier, N., Multiaxial fatigue life of a natural rubber crack initiation mechanisms and local fatigue life criterion, Ph.D. dissertation, Ecole des Mines de Paris, 2001. 

Mars, W.V., Heuristic approach for approximating energy release rates of small cracks under finite strain, multiaxial loading, in Elastomers and Components—Service Life Prediction Progress and Challenges, Coveney, V., Ed., OCT Science, Philadelphia, 2006, 89. 

Saintier, N., Cailletaud, G., and Piques, R., Crack initiation and propagation under multiaxial fatigue in a natural rubber, Int. J. Fatigue, 28, 61, 2006. 

Mars, W.V. and Fatemi, A., The correlation of fatigue crack growth rates in rubber subjected to multiaxial loading using continuum mechanical parameters. Rubber Chem. TechnoL, 80, 169, 2007. 

One of the most innovating contributions of the diagnostic model proposed in these guidelines is that it combines idiographic elements within a standardized multiaxial system, in contrast to the conventional, reductionist opinions that favor only one of these elements. 

With regard to the standardized multiaxial assessment, of the score of schemas that have been published (and reviewed by Mezzich, 1979), the ones that are currently most frequently seen are those included in the CIE-10 (World Health Organization, 1997) and the DSM-IV (APA, 1994). Although these systems vary in the number of axes they have, their contents do largely match up axis I (Clinical diagnoses) of the CIE-10 covers the contents of the first three axes of the DSM-IV axis II of the CIE-10 assesses the area of disabilities divided into four aspects (personal care, occupational, with the family, and social in general), and corresponds to axis V of the DSM-IV finally, axis III (Contextual factors) of the CIE-10 essentially matches axis IV of the DSM-IV. 

As pointed out earlier, the IGDA utilizes the CIE-10 for the first three axes of its multiaxial formulation. This diagnostic model is structured as follows ... 

The domains of this multiaxial formulation should be assessed with sensitivity to the patient s culture. That is to say, identification and rating of the importance of significant problems in health, functioning and social context should be performed bearing in mind the relevant cultural norms and customs. 

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