Biaxial loading

Biaxial load It is a loading condition in which a specimen/product is stressed in two different directions in its plane, i.e., as an example it is a loading condition of a pressure vessel under internal pressure and with unrestrained ends. 

Mitaka, Y. and Taya, M. (1985b). Stress field in and around a coated short fiber in an infinite matrix subjected to uniaxial and biaxial loadings. J. Appi Mech. 52, 19-24. 

The flaw spectrum approach may be capable also of correlating failure data obtained under conditions which appear to give different material behavior. For example, tensile, Izod, and dart drop impact tests all give different impact energies or toughness measures. In part, this may be explained by the simple idea that a different fraction of flaws is active in each test. Equal biaxial loading (as in dart drop) and uniaxial tension (as in tensile impact) give rise to different flaw activities thus it is to be expected that the number of crazes produced in each test will be different. 

For the moment, our interest is more in what takes place between these interfaces. To illustrate the types of quantitative questions that can be addressed by the theory of fine-phase microstructures, we first elaborate further on the character of these microstructures. As seen above, the martensitic microstructure is characterized by the presence of different variants. However, in the presence of an applied stress, the relative proportion of the different variants can be changed. The experiments are carried out in a biaxial loading apparatus like that shown schematically in fig. 10.27. If we align our Cartesian axes with the two loading directions, then the state of stress to which the sample is subjected can be characterized by the scalars cti and <72 which are a measure of the magnitudes of the load in these two loading directions. 

Fig. 10.27. Schematic of biaxial loading apparatus used to examine stress-induced transformations and resulting microstructures in martensites (courtesy of R. James).

Chu C.-H., Hysteresis and Microstructures A Study of Biaxial Loading on Compound Twins of Copper-Aluminum-Nickel Single Crystals, PhD Thesis, University of Minnesota, 1993. (unpublished)... 

Table 7.2 Selected experimental results for global multiaxial cyclic loading (external biaxial loading)... 

Francis PH, Wahath DE, Weed DN. First ply failure of G/E laminates under biaxial loadings. Fiber Sci Technol 1979 12 97-110. 

Jones DL, Poulose PK, Liebowitz H. Effect of biaxial loads on the static and fatigue properties of composite materials. In Multiaxial fatigue. ASTM STP 853 1985. pp. 413-27. 

Fujii T, Amijima s, Lin F, Sagami T. Study on strength and nonlinear stress—strain response of plain woven glass fiber laminates under biaxial loading. J Compos Mater... 

Susuki 1. Fatigue damage of composite laminate under biaxial loads. In Jono M, Inoue T, editors. Proceedings of mechanical behavior of materials — VI, vol. 2 WS7f3. Kyoto, Japan Pergamon Press 1992. pp. 543—8. July 29-August 2. 

Chen AS, Matthews FL. A review of multiaxial/biaxial loading tests for composite... 

Fujii T, Shina T, Okubo K. Fatigue notch sensitivity of glass woven fabric composite having a circular hole under tension/torsion biaxial loading. J Compos Mater 1994 28(3) 234-51. 

Fujii T, Lin F. Fatigue behavior of a plain-woven glass fabric laminate under tension/ torsion biaxial loading. J Compos Mater 1995 29(5) 573—90. 

Kawakami H, Fujii T, Morita Y. Fatigue degradation and hfe prediction of glass fabric polymer composite under tension/torsion biaxial loadings. J Reinf Plast Compos 1996 15 183-95. 

Perreux D, Joseph E. The effect of frequency on the fatigue performance of filament-wound pipes under biaxial loading experimental results and damage model. Compos Sci Technol 1997 57 353-64. 

Susuki I. Static and fatigue strength properties of composite laminates under in-plane biaxial loadings. In Proceedings of 5th international conference on biaxial/multiaxial fatigue and fracture 1997. pp. 79—89. Cracow, Poland. 

Inoue A, Fuji T, Kawakami H. Effect of loading path on mechanical response of a glass fabric composite at low cyclic fatigue under tension/torsion biaxial loading. J Reinf Plast Compos 2000 19(2) lll-23. 

Qi D, Cheng G. Fatigue behavior of filament-wound glass fiber reinforced epoxy composite tubes under tension/torsion biaxial loading. Polym Compos 2007 28(1) 116—23. 

Makris A, Vandenbergh T, Ramault C, Van Hemelrijck D, Lamkanfi E, Van Paepegem W. Shape optimisation of a biaxially loaded cruciform specimen. Polym Test 2010 29 216-23. 

One major difference between the two mechanisms of deformation is illustrated in Figure 5.7, which shows a failure envelope for PMMA under biaxial loading. The pure-shear line, defined = -o, marks the... 

FIGURE 3.7 Mechanics of the arterial wall (a) axisym-metric wall defonnation (b) element of the tube wall under biaxial loading. The 7 s ate longitudinal and circumferential internal stresses. 

Niebur, G. L., and Keaveny, T. M. (2001), Trabecular bone exhibits multiple failure surfaces in biaxial loading, Trans. Orthop. Res. Soc. 26 317. 

Engineering Sciences Data Unit (ESDU), Elastic buckling of unbalanced laminated fibre-reinforced composite plates (rectangular plates of AsBtDs type, all edges simply-supported under biaxial loading). Item No. 86020, S17, 1987. 

In many film applications the product is subjected to puncture or impact loads. These types of loads are applied perpendicular to the plane of the film. Therefore, the stresses act biaxially (in both the machine and transverse directions simultaneously) and are not represented well by a uniaxial test. Impact resistance tests are designed to biaxially load the film to measure its energy absorbing capability. 

Stump BW, Johnson LR (1977) The determination of source properties by the linear inversion of sesimograms. Bull. Seismo. Soc. Am. 67(6) 1489-1502 Suaris W, van Mier JGM (1995) Acoustic emission source characterization in concrete under biaxial loading. Materials and Structures 28 444-449... 

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