Influence of the Locality of Loading on the Stress Distribution in Anisotropic Shells of Revolution

The class of stress problems for orthotropic shells of revolution loaded along narrow ring zones or by forces concentrated in the meridional direction is analyzed on the basis of a refined model. It is established that the solutions of these two problems for essentially anisotropic shells do not fully agree     

Torsional buckling of cross-ply laminated orthotropic composite cylindrical shells subject to dynamic loading

This study considers torsional buckling of cross-ply laminated orthotropic composite cylindrical thin shells under loads, which is a power function of time. The modified Donnell type dynamic stability and compatibility equations are obtained first. These equations are subsequently reduced to a time dependent differential equation with variable coefficients by using Galerkin's method. The critical parameters are found analytically by applying the Ritz type variational method. According to theoretical solutions, numerical analyses are done.     

横截性理论在碰撞振动系统结构稳定问题中的应用

本文利用横截性理论研究了碰撞振动系统中的结构稳定问题。讨论了结构稳定、稳定、失稳及分叉之间的关系。     

Strain-rate history effects and microstructural aspects in lithium fluoride and aluminium single crystals after dynamic loading

Single crystals of LiF and Al are deformed in shear at a number of constant strain-rates in the range 10^–4 to 1600 s^–1. These constant rate tests are supplemented by a series of jump tests in which a sharp increment in strain rate is imposed during the quasi-static straining. Dislocation arrangements are observed by etch-pits technique for LiF crystals and by TEM for Al crystals. It is shown that cell sizes vary inversely with flow stress and strain-rate sensitivity.     

结构多点弹性正撞问题的解法

以多个质点和梁碰撞为例给出了结构多点弹性正撞问题的求解方法．并用算例说明方法的可行性．     

横截性理论在碰撞振动系统结构稳定问题中的应用

本文利用横截性理论研究了碰撞振动系统中的结构稳定问题。讨论了结构稳定、稳定、失稳及分叉之间的关系。     

船用921A钢动态断裂韧性测试研究

本文利用示波冲击试验,对船用９２１Ａ钢动态断裂韧性的测试方法进行了研究。     

结构塑性动力响应实验研究的简要综述

讨论和总结了结构塑性动力响应中的相似方法以及进行模化实验所应遵循的原则，对冲击载荷下多种结构塑性动力响应的实验研究进行了简要综述．     

Design of an Impact Loading Machine Based on a Flywheel Device: Application to the Fatigue Resistance of the High Rate Pre-straining Sensitivity of Aluminium Alloys

This paper presents a device that has been designed for tensile loading at medium impact rates (up to 10³ s^–1) and for performing either interrupted or failure tests. This machine allows us to apply prescribed pre-straining to the specimen, and then apply subsequent loading histories such as impact fatigue. Two specimen loading systems are considered, which make it possible to carry out tests with various ranges of force and various durations of time. A multi-CCD camera system is triggered by a chosen threshold from the force signal. The system is dedicated to the displacement measurement and gives both qualitative and quantitative information about the stretching mechanism leading to fracture. To illustrate the performance of the device, experimental results concerning impact tensile tests at a strain rate of about 300 s^–1 are presented, as well as consecutive impact-fatigue tests on two aluminium alloys.     

转子系统瞬时撞击刚度的定量计算方法

通过对转子与定子碰撞过程的线性化处理，得到了转子系统瞬时碰撞刚度的定量计算公式。由该公式确定的碰撞刚度不但与转子和定子的杨氏模量有关，而么与转子的径向速度有关。因此该公式较准确地确定了转子系统的碰撞过程。本文通过实例对如何运用此公式确定转子系统的碰撞刚度进行了详细的论述。