On the objective stress rate in co-moving coordinate system

The objective stress rate is a rather important problem in mechanics of finite deformation. In this paper, the objective stress rate in co-moving coordinate is derived by applying nonlinear geometric field theory of deformation. Problems, such ax targe extension coupled with rotation, and large shear deformation, are exemplified by using the new formula. Comparing with Jaumann’s stress rate and other formulae presented in current literature, the new result appears to be the reasonable one in co-moving coordinate system.     

On the representation of finite rotation in nonlinear field theory of continuum mechanics

One of the important basic theoretical problems in the development of continuum mechanics is the separation of finite strain and finite rotation at a point in the displacement field. Now it is certain that S-R decomposition theorem provides a rational theoretical solution for this problem. The purpose of this paper is to clarify some misleading basic concepts of finite rotation of deformed body in current literature, and to promote further progress.The detailed abstract of this paper was published in 1985 Shanghai International Conference of Nonlinear Mechanics. In the present paper some new results are included.     

实验应力分析的光电-计算机自动数据处理(PCP)程序研究

本文提出的光弹性数据自动分析处理PCP程序,使输入计算机的数据数量达到最小限度.文中采用陈至达[1](1962年)的光测应力分析基本方程,并导出适合于光弹性数据处理的三次样条函数.初步实践证明PCP程序较目前其他研究者提出的自动应力分析方法更为准确和节省计算时间.     

多重孔隙介质的有效应力定律

通过对双重孔隙介质有效应力的研究,建立了多重孔隙介质条件下的有效应力定律,发现了有效应力定律的唯一性依赖于孔隙介质本构关系的假设,提出了多重孔隙介质有效应力定律的所有可能形式。     

有限变形非对称弹性理论变分原理

应用有限变形S-R分解定理,将体力矩重新定义为内外两种体力矩之和,给出了相应的变形能增率表达式及其物理意义,并进一步补充和完善了有体力矩作用下的有限变形力学的功率变分原理和余功率变分原理。     

非线性尺规近似法在圆杆颈缩局部有限变形分析中的应用

形变局部化和不稳定的研究是当前力学问题的一个热点,其中最典型的问题是圆杆拉伸颈缩和滑移带的塑性分析。传统的微小变形弹塑性力学不能彻底解决此问题。本文采用以S(应变)-R(转动)分解定理为基础的非线性尺规数值计算法,并应用计算机模拟优化技术求出圆杆拉伸轴对称塑性有限变形的局部应变分布与发展形态。     

Inverse asymptotic solution method for finite deformation elasto-plasticity

I.IntroductionTheaccuracyofcomputermethodforsolvingengineeringproblemsfirstdependsonreliabilityofthetheorywhichisbeingapplied.Althoughfiniteelementmethodhasgainedgreatsuccessesinengineeringapplication.However,duetothetheoreticallimitationsofclassicalmecha…     

弹塑性有限变形力学的反逆渐近解法

最近几十年中,近代力学的非线性有限变形理论在概念与方法上有许多重要的进展([1],[2],[3]等).本文旨在说明自然拖带系描述法与Stokes-陈分解定理如何结合反过渐近解法于有效解答弹塑性有限变形力学问题应用至工程设计目的.文中举半平面冲压大变形为典型数值解例.     

EDITORIAL COMMITTEE OF "APPLIED MATHEMATICS AND MECHANICS

ＥＤＩＴＯＲＩＡＬＣＯＭＭＩＴＴＥＥＯＦ＂ＡＰＰＬＩＥＤＭＡＴＢＥＭＡＴＩＣＳＡＮＤＭＥＣＨＡＮＩＣＳ＂Ｅｄｉｔｏｒ－ｉｎ－ｃｈｉｅｆ：ＣｈｉｅｎＷｅｉｚａｎｇ（钱伟长）ＶｉｃｅＥｄｉｔｏｒ－ｉｎ－ｃｈｉｅｆ：＇ＴａｎＨａｏｓｈｅｎｇ（谈镐生），Ｙｅ...     

ON UNILATERAL CONTACT LARGE DEFORMATION PROBLEM WITH FRICTION(Ⅱ)—NONLINEAR FINITE ELEMENT TECHNIQUE AND ITS APPLICATION

Based on the variational equation derived in ref.[1]a nonlinear incremental F.E.equation is formulated for unilateral contact elastic and plastie large deformationproblems.A new technique-co-moving coordinate finite element method is introduced,and a practical mathematical model for large deformation contact problem is described.To show the effectiveness of the method,problems of contact large deformation ofcantilever beam.cireular plate,as well as metal ring are computed.Compared withexperiments.the results show good agreements.