刚性微粒填充的高聚物非线性粘弹性本构关系的微力学分析

在应变具有可加性条件下,本文分析表明Eshelby线性微力学理论,包括其等效包含体方法和相应的平均化方法可推广应用于研究高刚度微粒填充高聚物的非线性粘弹性本构关系。     

爆炸作用下钢板层裂的数值分析

用一维运动模型对高能炸药在钢板表面接触爆炸时钢板中应力波的传播及其在钢板自由面上反射后引起的层裂现象进行了数值分析,并和前几年在我国进行的实验结果作了比较.发现当钢板采用流体弹塑性模型,并采用损伤积累层裂准则的情况下,计算所得的主裂片厚度是和实验结果合理地符合的.提出了一个计算主裂片厚度的近似公式,对实验中出现的多层的呈云母状结构的次裂片现象也作出了较满意的解释.     

THE CORRECTION OF "ON THE MOTTON OF FLYING PLATE UNDER EXPLOSIVE ATTACK

Chu Chao-hsiang and Jiang Da-he,On the Motion of Flying Plate under Ex-plosive Attack,Applied Mathematics and Mechanics,Vol.1,No.3 (1980).PP.293-304.1.Eq.(2.2)should be as follows:     

短纤维增强对聚碳酸酯非线性粘弹性性能的影响

本文采用SHP B装置研究了聚碳酸酯和短玻璃纤维增强聚碳酸酯在10-4～103/秒应变率范围和有限应变条件下的非线性粘弹性力学行为。根据Coleman和Noll的材料本构关系理论和本文实验结果,提出聚碳酸酯的本构方程 m（e,（?））=E0e+e2+e3+E1 integral from n=0 to 1（（?）exp（-（t-）/1）d）+E2 integral from n=0 to 1（（?）exp（-（t-）/2）d+（?）） 并进而得到短纤维增强聚碳酸酯的一个相当简单的本构方程 frm=m（e,（?）） 在加卸载全过程,两种本构方程的理论计算值都能满意地与实验结果相一致。     

Numerical Analysis of the Spallation of Steel Target under Explosive Loading

A numerical analysis of the propagation of stress waves and theallied scabbing phenomena in a steel plate under explosive attack is made,by using a model of one-dimensional flow.The results are compared withour experimental results which were carried out several years ago.Itis found that,in case the hydrodynamic-elastoplastic model for steelplate and the cumulative damage spall criterion are used,the calculatedthickness of the major spall is in reasonable agreement with that obtainedin the experiments.An approximate formula for the thickness of themajor spall is presented and the“mica-splitting”phenomenon about theminor spalls observed in the experiments is satisfactorily explained.     

On the Motion of Flying Plate under Explosive Attack

The one-dimensional problem of the motion of a rigid flying plate under explosive attack hasan analytic solution only when the polytropic index of detonation products equals to three.Ingeneral,a numerical analysis is required.In this paper,however,by utilizing the“weak”shockbehavior of the reflection shock in the explosive products,and applying the small parameter pur-terbation method,an analytic,first-order approximate solution is obtained for the problem of flyingplate driven by various high explosives with polytropic indices other than but nearly equal to three.Final velocities of flying plate obtained agree very well with numerical results by computers.Thusan analytic formula with two parameters of high explosive(i.e.detonation velocity and polytropicindex)for estimation of the velocity of flying plate is established.     

爆炸、冲击和非线性波

本文讨论了爆炸、撞击和非线性波领域内的三个问题:(1)非线性波现象。(2)正问题——爆炸和撞击机械效应的初边值问题。(3)反问题——由波的传播来研究材料的动力学特性。     

环氧树脂在高应变率下的热粘弹性本构方程和时温等效性

在—20℃～100℃的温度范围内用SHPB实验技术研究了环氧树脂在高应变率(10~2～10~3s~(-1))和直到7.5％大应变下的粘弹性力学行为。提出了一个简单实用的非线性热粘弹性本构方程,并发现存在一种时温等效性。在加卸载全过程中,理论计算值与实验结果相当符合。     

钱学森先生在力学所初建的日子里

著名力学家钱学森冲破重重阻挠于1955年10月8日回到祖国,并与著名力学家钱伟长等一道于1956年1月16日创建了中国科学院力学研究所。50年来,力学所坚持钱学森倡导的"技术科学"思想,为力学学科的发展做出了自主创新、引领发展的重要贡献。已成为以国家重大需求为牵引、以基础性研究为本、在国际力学界有相当影响的国家力学研究基地。2005年12月6日中国科学院力学研究所举行了"庆祝中国科学院力学研究所建所50周年暨钱学森回国50周年大会"。本期刊出洪友士的"力学研究所五十年"等7篇大会报告,以饷读者,并以此向力学所和钱学森先生表示热烈祝贺。     

Numerical analysis of the spallation of steel target under explosive loading

A numerical analysis of the propagation of stress waves and the allied scabbing phenomena in a steel plate under explosive attack is made, by using a model of one-dimensional flow. The results are compared with our experimental results which were carried out several years ago. It is found that, in case the hydrodynamic-elastoplastic model for steel plate and the cumulative damage spall criterion are used, the calculated thickness of the major spall is in reasonable agreement with that obtained in the experiments. An approximate formula for the thickness of the major spall is presented and the mica-splitting phenomenon about the minor spalls observed in the experiments is satisfactorily explained.