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991.
992.
IntroductionThedynamicandcontrolofcoupledrigid_flexiblesystemisaleading_edgeresearchsubjectthathasdrawnextensiveattentionfromtheacademiccommunityintheworld[1].TheresearchconductedbyKaneetal.in 1 987[2 ]suggestedthat,thetraditionalmodelapplyingstructuraldynamicsassumptionaboutelasticdeformationindiscriminately[3,4 ],ineffect,hasneglectedtheso_called“dynamicstiffening”effectresultedfromcoupledrigid_flexiblesystem .Therefore ,itisofparticularimportancetoresearchtheactionofcoupledrigid_flexibles… 相似文献
993.
A two-dimensional mesoscale simulation method based on the natural element method, which is a kind of meshless method, is developed and applied to the analysis of overall elastic moduli, macro yield stress and void-linking fracture. The calculated results are compared with the theoretical solutions for overall elastic moduli, the experimental macro yield stress for aluminum and brass as well as the improved Gurson’s yield function, and the experimental void linking fracture to show the validity of the proposed method. 相似文献
994.
随着城市化进程加快,济南市在城市建设中面临日益严重的环境工程地质问题。为了更好地服务于城市建设,做好岩土地基的工程地质环境质量评价与分区有重要实际意义。本文分析了济南市区的工程地质环境条件,研究了济南市区岩土地基工程地质环境质量评价模型与优势指标,并采用BP神经网络模型对济南市区的岩土地基工程地质环境质量进行评价与分级。 相似文献
995.
996.
A semi-analytical and semi-numerical method is proposed for the dynamic analysis of foundations. The Lamb's solution and the approximate formulae were used to establish the relation of the contact force and deflection between the foundation and soil. Therefore, the foundation can be separated from soil and analyzed by FEM as for the static cases. The plate can be treated as that the known forces are acting on the upper surface, and the contact pressure from soil can be represented as the deflection. So that only the plate needs to be divided into elements in the analysis. By this method, a series of vibration problems, including various shapes and rigidities of foundations, different excitation frequencies, were analyzed. Furthermore, it can be used for the embedded foundation. The numerical examples show that this method has simplicity, highly accurate and versatile. It is an effective method for the dynamic analysis of foundations. 相似文献
997.
The theoretic solution for rectangular thin plate on foundation with four edges free is derived by symplectic geometry method. In the analysis proceeding, the elastic foundation is presented by the Winkler model. Firstly, the basic equations for elastic thin plate are transferred into Hamilton canonical equations. The symplectic geometry method is used to separate the whole variables and eigenvalues are obtained simultaneously. Finally, according to the method of eigen function expansion, the explicit solution for rectangular thin plate on foundation with the boundary conditions of four edges frees are developed. Since the basic elasticity equations of thin plate are only used and it is not need to select the deformation function arbitrarily. Therefore, the solution is theoretical and reasonable. In order to show the correction of formulations derived, a numerical example is given to demonstrate the accuracy and convergence of the current solution. 相似文献
998.
裂纹体弹性波散射问题研究概述 总被引:4,自引:0,他引:4
近30年来,随着地震探矿技术、定量无损检测技术、雷达和声呐技术的发展,以及对动态断裂及高速冲击下材料动态特性等问题的研究,弹性波散射理论的研究引起了国内外力学界及其他学科许多科学工作者的普遍关注。至今,人们在这一领域已进行了大量的研究工作,并得到了很大的发展,而所取得的成果又为应用技术的发展提供了理论依据,所以它已成为当前应用力学界一个较为活跃的前沿课题。本文将对近年来关于裂纹体弹性波散射问题的有关研究现状和基本方法作较为系统的介绍。 相似文献
999.
1000.
N. I. Ostrosablin 《Journal of Applied Mechanics and Technical Physics》2006,47(4):564-572
This paper deals with the general formulas of affine transformations that preserve invariance of the static equations of the
linear theory of elasticity in the case of arbitrary anisotropic materials. The invariance of the equations with respect to
affine transformations allows one to model a given anisotropic material by another material. All anisotropic materials are
divided into classes of mutually congruent materials. The congruency conditions are obtained for orthotropic and isotropic
materials and for orthotropic and transversely isotropic materials.
__________
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 4, pp. 124–134, July–August, 2006. 相似文献