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941.
沈惠川 《应用数学和力学(英文版)》1984,5(6):1791-1801
In this paper the Euler equation of the deflection of clastic thin plate is reduced to the equation with schrödinger form by the principle of quantum electro-dynamics. Then we can obtain the general solution of deflection of eleastic thin bending plate by the joint action of dynamical lateral pressure, force in central surface and external field on the elastic base. 相似文献
942.
In this paper we study initial value problems on the infinite interval:where x, f∈E~m, y, g∈E~n,εare real small positive parameters, 0≤t<+∞. Oncondition that g_y(t) is nonsingular and under other assumptions, we have proved that thereare serial (k+m~*)-dimensional manifolds{S_R(e)}∈E~(m+n)such that (I.I)degeneratesregularly provided(ξ(e), η(e))∈S_R(e). Besides, the R-order asymptotic expansions ofsolutions are constructed, and their errors are estimated. 相似文献
943.
944.
付宝连 《应用数学和力学(英文版)》1985,6(11):1069-1081
This paper further extends the applications of the reciprocal theorem to calculating thenatural frequencies of rectangular elastic thin plates on the basis of [1]. Applying thepresented method. there is no need to solve governing differential equations. it is onlynecessary to solve a simple integral equation after using the reciprocal theorem between thebasic system and the actual system.Using the idea of the generalized edge simply supported and introducing the frequencymatrix. then all frequency equations of the rectangular plates with two opposite edgessimply supported and other two opposite edges variously suppored are obtained together.This is a simple convenient and general method for calculating the frequencyequations of the rectangular plates. 相似文献
945.
根据嘉兴市某住宅小区多套房屋产生漏水的现象,分析其产生的原因主要是因为墙体裂缝、屋面裂缝、顶板裂缝造成的,并针对原因提出了一些切实可行的处理办法. 相似文献
946.
The scattering of Love waves by an interface crack between a piezoelectric layer and an elastic substrate is investigated
by using the integral transform and singular integral equation techniques. The dynamic stress intensity factors of the left
and the right crack tips are determined. It is found from numerical calculation that the dynamic response of the system depends
significantly on the crack configuration, the material combination and the propagating direction of the incident wave. It
is expected that specifying an appropriate material combination may retard the growth of the crack for a certain crack configuration.
Project supported by the National Natural Science Foundation of China (No. 19891180), the Fundamental Research Foundation
of Tsinghua University (JZ 2000.007) and the Fund of the Education Ministry of China. 相似文献
947.
朱锡雄 《宁波大学学报(理工版)》1989,(1)
本文在内参量热力学的理论框架内详细讨论了线弹性裂纹体的裂纹扩展问题。对线弹性断裂力学中所涉及到的各种能量关系作了统一的整理,其中包括Irwin的弹性能释放率——裂纹扩展力,Griffith的脆性断裂准则,以及Irwin-Kies的柔度公式和Paris的位移公式。本文以中心裂纹体为例,详细计算了裂纹扩展的稳定性,并区分恒载荷和恒位移两种情况,对材料断裂韧性测试中所遇到的失稳扩展,稳定扩展以及迸发现象提供了理论说明。 相似文献
948.
According to the Griffith criterion, a crack propagation occurs, provided that the derivative of the energy functional with respect to the crack length reaches some critical value. We consider a generalization of this criterion to the case of nonlinear cracks satisfying a nonpenetration condition and investigate the dependence of the shape derivative of the energy functional on the crack shape. In the paper, we find the crack shape which gives the maximal deviation of the energy functional derivative from a given critical value and, in particular, prove that this optimality problem admits a solution. 相似文献
949.
The fracture toughness enhancement of mode III crack in transformation toughened ceramics such as Ce-TZP and Mg-PSZ is predicted by using a pressure sensitive transformation criterion and the weight function method. The theoretical analyses of the toughening effect for both stationary and steady-state growing crack are given, respectively. The results show that the toughening is only associated with crack growth and there is no toughening effect for stationary crack.The project was supported by the National Science Foundation of China 相似文献
950.
In this paper, a new analytical-engineering method of closed form solution for stress intensity factors of shear modes for 3-D finite bodies with cracks is derived by the time saving energy release rate method. Hence a complete series of useful results of stress intensity factorsK
II andK
III can be obtained. And the results provided by this method are in good agreement with some obtained by other methods. 相似文献