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181.
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
182.
183.
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
184.
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
185.
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
186.
R. Wilfinger J. Lettry A. Fabich H. Aiginger K. Poljanc R. Catherall M. Eller 《The European physical journal. Special topics》2007,150(1):373-378
Thermal stress-waves are generated in the solid target
material when the proton beam interacts. These stress waves excite
natural oscillations of the target or cause plastic deformations.
Hence, an experimental setup with a laser Doppler vibrometer
[CITE] was developed to investigate free surface
vibrations of cylindrical targets. The target configurations for
RIB and conventional neutrino beams (CNGS project) were
investigated to analyze proton induced thermal stress-wave
generation and propagation. 相似文献
187.
188.
本文对比研究了关于弹性波模拟中的曲边地表形状处理的两种方法,一种是用给定的实际介质数值划定的地表形状,另一种是用样条插值逼近地表形状.本文采用有限元方法进行弹性波数值模拟,给出了基于这两种方法计算的数值例子,并对结果进行了分析比较.结果表明使用后一种方法对地表进行处理时,地表人工离散产生的干扰明显减少,优于前一种方法. 相似文献
189.
In this paper, the Authors study the small oscillations of an inviscid liquid under zero gravity in a container of revolution
with elastic bottom, considered as a membrane or a plate, and anchored edge. They obtain the equations of the displacements
of the free surface and the bottom and they reduce these equations to a functional equation in a suitable Hilbert space. By
using the methods of Functional Analysis the Authors prove the existence of the small oscillations.
Research partially supported by GNFM, MURST (Italy). 相似文献
190.
Initial-boundary value problems with Dirichlet and Neumann conditions arising in the theory of bending of plates with transverse
shear deformation are reduced to time-dependent boundary integral equations by means of layer potentials. The solvability
of these equations is then investigated in Sobolev-type spaces.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献