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961.
本文研究了线性铁磁性简支梁在轴向力和横向磁场作用下的振动和动力稳定性,导出了有涡电流时梁的动力学方程,并讨论了涡电流对梁动特性的影响. 相似文献
962.
A brief review of the literatures on the titled subject is given. A set of wave equations, taking the inertial coupling effect
between soil skeleton and pore water into account, are established for saturated soils. The preliminary analysis shows that
the nature of wave propagation is mainly influenced by permeability coefficient,k. There are three types of waves, two (P-and S-wave) propagating through soil skeleton and one(P-wave) through pore water.
For a soil with large value ofk, compression wave velocity through pore water will be greater than that through single-phased water, and ask→∞, the former could be
times as great as the latter. For a soil with extremely low permeability, the compression wave velocity could be either less
or greater than that through single-phased water, depending on the rigidity of the soil passing through. Some phenomena observed
from tests presented in the literature may be reasonably explained by the proposed theory herein, and thus more reliable parameters
of soil could be obtained from wave velocity measurements. Further studies on this subject are still needed.
This paper is a part of the dissertation of the first author for the Ph.D. degree, the second author is his advisor. 相似文献
963.
本文根据弹性薄壳理论,考虑了弹性地基径向和切向抗力的影响,解决了变截面圆弧壳地基梁的难题,作者所提出的近似解析法和加权余量法、传递矩阵法较有限单元法简便. 相似文献
964.
采用压痕实验获得材料性能的研究现状 总被引:7,自引:1,他引:7
本文综述了采用压痕实验获得膜基体系中薄膜弹性,塑性,蠕变性能的研究进展,并指出了目前研究中存在和需要解决的问题。 相似文献
965.
966.
L. A. Tkacheva 《Journal of Applied Mechanics and Technical Physics》2005,46(2):230-238
The Wiener-Hopf technique is used to obtain an analytical solution for the problem of vibrations of a floating semi-infinite elastic plate due to earthquake-induced vibrations of a bottom segment. An explicit solution is obtained ignoring the inertial term. The surface-wave amplitudes and ice-plate deflection are studied numerically as functions of the frequency and position of the vibrating bottom segment, ice thickness, and fluid depth.Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 46, No. 2, pp. 98–108, March–April, 2005. 相似文献
967.
Size-dependent effective elastic constants of solids containing nano-inhomogeneities with interface stress 总被引:1,自引:0,他引:1
The fundamental framework of micromechanical procedure is generalized to take into account the surface/interface stress effect at the nano-scale. This framework is applied to the derivation of the effective moduli of solids containing nano-inhomogeneities in conjunction with the composite spheres assemblage model, the Mori-Tanaka method and the generalized self-consistent method. Closed-form expressions are given for the bulk and shear moduli, which are shown to be functions of the interface properties and the size of the inhomogeneities. The dependence of the elastic moduli on the size of the inhomogeneities highlights the importance of the surface/interface in analysing the deformation of nano-scale structures. The present results are applicable to analysis of the properties of nano-composites and foam structures. 相似文献
968.
969.
The evolution of a solitary wave propagating through a microstructural material (composite) is studied on the basis of wavelet analysis. A specific feature of the solution technique proposed is the use of Mexican hat (MH) wavelets, which are elastic wavelets, i.e., they are solutions of the basic system of wave equations for an elastic material with a microstructure. The initial wave profile is also chosen in the form of the MH-wavelet. Primary attention is given to the relationship among the profile behavior, wave bottom length, and characteristic microstructure length. A computer analysis conducted demonstrates that the approach proposed allows us to detect the basic wave effects: splitting of the wave into two modes with different phase velocities, simultaneous propagation of both modes in the components of the composite, and strong dependence of the evolution rate on the characteristic lengths of the wave and microstructure 相似文献
970.
基于广义胡克定律及混和变量弹性波方程,解析求得各层介质内位移、应力传递矩阵,给出了直角坐标系下各向异性层状介质中弹性波的传播矩阵解法.该方法适用于非轴对称各向异性和点源作用,较好地解决了数值计算中有效数字精度损失问题.数值结果表明,计算效率、准确性及稳定性均较好. 相似文献