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991.
Calculating response spectral moments by complex modal analysis 总被引:1,自引:0,他引:1
Response spectral moments are useful for system reliability analysis. Usually, spectral moments are calculated by the frequency
domain method. Based on the time domain modal analysis of random vibrations, the authors present a new method for calculating
response spectral moments through response correlation functions. The method can be applied to both classical and non-classical
damping cases and to three kinds of random excitations, i.e., white noise, band-limited white noise, and filtered white noise.
Project supported by the National Natural Science Foundation of China. 相似文献
992.
The general solution of the electroelastic problem for a transversely isotropic hyperboloid of revolution is used to find the stress concentration near a hyperboloidal neck in a piezoceramic body subjected to bending. The solution is a sum of four partial solutions for the case where the forces and the normal component of the induction vector on the neck surface are equal to zero. Numerical examples are given for specific external loads and properties of the body. The stress components and normal component of the induction vector near the neck vertex are plotted as a function of the external load and neck curvature 相似文献
993.
The overall bending of circular ring shells subjected to bending moments and lateral forces is discussed. The derivation of the equations was based upon the theory of flexible shells generalized by E.L. Axelrad and the assumption of the moderately slender ratio less than 1/3 (i.e., ratio between curvature radius of the meridian and distance from the meridional curvature center to the axis of revolution). The present general solution is an analytical one convergent in the whole domain of the shell and with the necessary integral constants for the boundary value problems. It can be used to calculate the stresses and displacements of the related bellows. The whole work is arranged into four parts: (Ⅰ) Governing equation and general solution; (Ⅱ) Calculation for Omega-shaped bellows; (Ⅲ) Calculation for C-shaped bellows; (Ⅳ) Calculation for U-shaped bellows. This paper is the first part. 相似文献
994.
有面内张力和剪力的四边支承各向异性平行四边形板振动、屈曲和弯曲的精确解 总被引:1,自引:0,他引:1
给出了弹性地基上四边支承的各向异性平行四边形板在面内张力和剪力作用下自由振动、屈曲和弯曲问题的精确的解析解。此解是利用叠加法得到的重富立叶级数解。与现有结果的比较验证了解的精确性。并给出了一些固定边和简支边组合的多种倾斜角的平行四边形板的自由振动、屈曲和弯曲的数值结果。 相似文献
995.
The last decade has witnessed an important role of magneto-rheological dampers in the semi-active vibration control on the basis of empirical models. Those models established by fitting experimental data, however, do not offer any explicit expressions for the stiffness and the damping of magneto-rheological dampers. Hence, it is not easy for engineers to get any intuitive information about the effects of stiffness and damping of a magneto-rheological damper on the dynamic performance of a controlled system. To manifest the nonlinear properties of a magneto-rheological damper, this paper presents the hysteretic phenomena and the additional nonlinear stiffness of a typical magneto-rheological damper in terms of equivalent linear stiffness and equivalent linear damping. Then, it gives a brief discussion about the effect of nonlinear stiffness on the vibration control through the numerical simulations and an experiment for the semi-active suspension of a quarter car model with a magneto-rheological damper installed. Both numerical simulations and experimental results show that the additional nonlinear stiffness in the magneto-rheological damper is remarkable, and should be taken into consideration in the design of vibration control. 相似文献
996.
E. I. Bespalova 《International Applied Mechanics》2007,43(5):526-533
The bending vibrations of polygonal (L-shaped) plates with different shapes and boundary conditions are studied. The natural
frequencies are calculated using the inverse-iteration and Kantorovich-Vlasov methods. To take the configuration of the domain
into account, the fictitious domain method and an analog of the force method of structural mechanics are used. Different trends
in the dependence of the lowest natural frequency of an L-shaped plate on its geometry are illustrated for different boundary
conditions.Acorrelation between the extreme values of the bending frequency and some relations for the energy characteristics
of the plate is established
__________
Translated from Prikladnaya Mekhanika, Vol. 43, No. 5, pp. 63–72, May 2007. 相似文献
997.
998.
各向异性矩形薄板弯曲问题的一般解 总被引:3,自引:0,他引:3
给出了各向异性矩形薄板弯曲问题微分方程的一般解。可以求解任意载荷作用下各种边界的弯曲问题。以四边固支的正方形板为例进行了数值计算。 相似文献
999.
This is one of the applications of Part (I), in which the angular stiffness, the lateral stiffness and the corresponding stress distributions of C-shaped bellows were
calculated. The bellows was divided into protruding sections and concave sections for the use of the general solution (I), but the continuity of the stress resultants and the deformations at each joint of the sections were entirely satisfied.
The present results were compared with those of the other theories and experiments, and are also tested by the numerically
integral method. It is shown that the governing equation and the general solution (I) are very effective.
Contributed by HUANG Qian
Biography: ZHU Wei-ping (1962-) 相似文献
1000.
均布载荷作用下带边缘大波纹膜片的非线性弯曲 总被引:6,自引:0,他引:6
采用轴对称旋转壳体的简化Reissner方程,研究了在均布载荷作用下具有硬中心的带边缘大波纹膜片的非线性弯曲问题.应用积分方程方法,获得了具有夹紧固定和滑动固定两种外边界的膜片的特征关系,即荷载-中心挠度曲线.作为算例,给出了夹紧固定膜片中的应力分布. 相似文献