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151.
《Acta Mechanica Solida Sinica》2011,(Z1):95-106
Stress calculation formulae for a ring have been obtained by using Airy stress function of the plane strain field with the decomposition of the solutions for normal stresses of Airy biharmonic equation into two parts when it is loaded under two opposite inside forces along a diameter. One part should fulfill a constraint condition about normal stress distribution along the circumference at an energy valley to do the minimum work. Other part is a stress residue constant. In order to verify these formulae and the computed results, the computed contour lines of equi-maximal shear stresses were plotted and quite compared with that of photo-elasticity test results. This constraint condition about normal stress distribution along circumference is confirmed by using Greens’ theorem. An additional compression exists along the circumference of the loaded ring, explaining the divorcement and displacement of singularity points at inner and outer boundaries. 相似文献
152.
Mathematical Notes - 相似文献
153.
154.
Huan-You Wang Hui Xu Tie-Tie Huang Chao-Sheng Deng 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,62(1):39-43
The density function perturbation theory (DFPT) is employed to study
the linear thermal expansion and heat capacity at constant pressure
(with the quasiharmonic approximation) for wurtzite GaN. The
calculated results of linear thermal expansion coefficient and heat
capacity at constant pressure are compared with the available
experimental data in a wide temperature range. Generally these
properties calculated agree well with experimental data except at
high temperature, thus it suggests the thermal expansion and heat
capacity can be well calculated from this first-principle approach. 相似文献
155.
A. I. Egorov 《Computational Mathematics and Mathematical Physics》2008,48(6):912-917
The observability problem for beam vibrations described by a fourth-order partial differential equation with various boundary conditions is considered. Dynamic observability problems are solved in terms of boundary conditions and observations of the beam state at certain fixed instants of time. 相似文献
156.
I. J. Gnip S. I. Vaitkus V. I. Kersulis S. A. Veyelis 《Mechanics of Composite Materials》2007,43(5):433-444
The results obtained in an experimental investigation of deformability of expanded polystyrene (EPS) under short-term compression
are presented. The density of EPS varied from 13 to 28 kg/m3. The method of design of experiments was used to determine the elastic modulus and the ultimate strain (corresponding to
the end of quasi-linear deformability) under compression stresses operating perpendicularly and parallel to the faces of EPS
products. A graphical interpretation of the models is also presented. Based on the experimental data obtained, it was concluded
that the expanded polystyrene was homogeneous in mutually perpendicular planes with respect to its deformability in compression.
__________
Translated from Mekhanika Kompozitnykh Materialov, Vol. 43, No. 5, pp. 639–656, September–October, 2007. 相似文献
157.
158.
Mari Grobbelaar‐Van Dalsen 《Mathematical Methods in the Applied Sciences》2005,28(4):443-455
In this paper a model for the vibrations of a one‐dimensional hybrid thermo‐elastic structure consisting of an extensible thermo‐elastic beam which is hinged at one end, with a rigid body attached to its free end, is studied with a view to establishing the existence of a unique solution in a weak sense. The model takes account of the effect of stretching on bending and rotational inertia. By treating eigenvalue problems with the spectral parameter also in the boundary conditions, we are able to employ the method of Faedo–Galerkin approximations. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
159.
An exact solution is proposed in this paper based on the elasticity theory for sound reflection from an infinite laminated plate and transmission through it, and some phenomena of sound propagation in an isotropic media are also discussed. Some examples given here could be used to test approximate models of laminated plates. 相似文献
160.
A UNIFIED ENERGY APPROACH TO A CLASS OF MICROMECHANICS MODELS FOR MICROCRACKED SOLIDS 总被引:2,自引:0,他引:2
Y.Huang K.C.Hwang 《Acta Mechanica Solida Sinica》1995,8(2):110-120
Micromechanics models have been developed for the determination ofthe elastic moduli of microcracked solids based on different approaches andinterpretations,including the dilute or non-interacting solution,the Mori-Tanakamethod,the self-consistent method,and the generalized self-consistent method.It isshown in the present study that all these micromechanics models can be unified withinan energy-equivalence framework,and that they differ only in the way in which themicrocrack opening and sliding displacements are evaluated.Relevance to thedifferential methods and the verification of these models are discussed. 相似文献