经典弹性力学与应用力学方法

通过对经典弹性力学半反演法的特点与应用力学方法的特点的对比,阐明应用力学方法是在经典弹性力学半反演法的基础上发展出来的,指出应用力学方法源自经典弹性力学．讨论了在弹性力学的教学过程中,突出半反演法和应用力学方法之间的关联,会产生很好的教学效果．     

应用力学方法初探

应用力学在二十世纪初期，大放异彩，大获成功。力学在解决现代工程问题的过程中，创造性地发展了一套行之有效的应用力学方法。本文对应用力学在中国的传播与发展、有关应用力学的论述、应用力学方法的范例、应用力学方法的意义与特点、以及应用力学与数学力学、应用力学与有限元法之间的联系等方面作了介绍和讨论。阐明了应用力学方法必然产生的实际背景和理论根源。并指出：深刻探究与理解应用力学的范例是学习与掌握应用力学方法的有效途径。     

钱学森对近代力学的发展所做的贡献

钱学森先生为了研究实现高速飞机和远程火箭的可能性,在空气动力学、固体力学、稀薄气体力学和飞行力学等应用力学领域做出了杰出的贡献;并且开创了喷气推进学、工程控制论和物理力学等技术科学新分支.他对近代力学以至技术科学的内涵和发展方向,发表过全面系统的论述.在这篇文章中将介绍他的主要研究成果,并对他的科学思想作一初步的探讨.      

钱伟长先生对力学和应用数学的贡献

为了缅怀我国近代力学的奠基人之一、著名的力学家和应用数学家钱伟长先生,该文较为详细地回顾了他在力学和应用数学的若干重要方面的开创性和奠基性的工作,主要包括在弹性板壳的内禀理论、弹性圆薄板大挠度理论、环壳理论及其应用、广义变分原理及在有限元计算中的应用、奇异摄动理论、理性力学等方面的学术成就,还回顾了他在发展我国力学事业和培养我国力学人才等方面的巨大贡献.     

关于第14届国际理论与应用力学会议

由国际理论与应用力学联合会(IUTAM)主办的第14届国际理论与应用力学会议于1976年8月30日—9月4日在荷兰举行,有41个国家1027名代表参加,约270篇论文。在大会上作专题报告的有荷兰科学院院长Casimir:数学、力学和现代物理,J.H.Argyris:电子计算机和力学,冯元祯(Y.C.Fung):生物力学;G.K.Batchelor:      

评王敏中等编的《数学弹性力学研究的若干进展》

<正>最近,王敏中教授送给我他和他的学生编的一本专著《数学弹性力学研究的若干进展》。书中收集了几十年来他和学生们在弹性力学方面最重要的研究论文40篇。王敏中和我在北京大学力学系同一个教研室共事数十年,他以往的研究每有新发现都在一定的范围或讨论班上做报告,所以他的研究方向和成果,我虽然不能说完全熟悉,也略知一二。这本书一到手,我便忍不住先浏览一遍。     

上海大学力学学科简介

历史沿革上海大学力学学科起源于1984年由钱伟长院士所创建的上海市应用数学和力学研究所。1984年建立了固体力学博士点及流体力学硕士点;1985及1996年,应用数学和力学以及应用力学学科先后被     

国际"分析力学近代发展"讨论会

由国际理论与应用力学联合会(IUTAM)、国际力学与数学相互关系协会(ISIMM)、意大利理论与应用力学学会和意大利都灵科学院联合组织的“分析力学近代发展”讨论会于1982年6月在都灵举行。有二十三个国家的代表参加。讨论会共有二十四     

国际"分析力学近代发展"讨论会

由国际理论与应用力学联合会(IUTAM)、国际力学与数学相互关系协会(ISIMM)、意大利理论与应用力学学会和意大利都灵科学院联合组织的"分析力学近代发展"讨论会于1982年6月在都灵举行。有二十三个国家的代表参加。讨论会共有二十四...     

应用数学和力学的结合-Ⅱ——钱伟长的代表作

探讨钱伟长先生对于《应用数学和力学相结合》的研究理念.文中以钱伟长的代表作为例,对《应用数学和力学相结合》的内涵作了说明.弹性板壳内禀理论,弹性圆薄板大挠度问题的摄动解法和拉格朗日乘子法在变分原理中的应用,可以认为是钱伟长的3个代表作.通过对这3个代表作的剖析,可以具体看到钱伟长在研究实践中,如何着力于《应用数学和力学相结合》的研究理念,而取得丰硕的创新成果.     

科学与工程中的应用力学

回顾1600年至1900年间力学、19世纪物理学和同时期的工程教育的发展史,描述了应用力学的发展及其与科学和工程的关系．随之讨论现代物理学、现代工程学和作为科学与工程的一门学科的应用力学的形成,后者被《AppliedMechanicsReviews》杂志分为94个学科方向共10个门类．总结了科学与工程之间的关系以及应用力学与其它学科的相互影响．     

工程科学前沿的拓荒者——郑哲敏

郑哲敏先生是著名力学家, 我国爆炸力学的奠基人和开拓者, 2012年度国家最高科学技术奖获得者. 本文回顾了郑哲敏先生在过去60多年中非常丰富的科研活动, 特别是他在爆炸加工、地下核爆、爆炸排淤、穿破甲、煤与瓦斯突出、水合物开采、水弹性动力学、材料力学行为等方面的杰出学术贡献. 这些工作闪耀着鲜明的工程科学特点, 即着眼国家重大需求, 从错综复杂的问题中概括提炼关键物理因素, 创新理论, 进而指导实践. 郑哲敏先生的科学贡献和学术思想, 对于力学学科发展, 有着重要的现实意义和参考价值.     

Applied Problems in the Mechanics of Strain Hardening of Structural Metallic Materials

Some applied problems of the mechanics of strain-hardening processes in metallic materials are considered. To solve these problems, the concept of loading surface, which separates the elastic and elastoplastic domains in the stress space, is used. Strain-hardening models are analyzed. For a wide range of steels and alloys, the most commonly used hypothesis of isotropic-and-kinematic hardening is experimentally justified __________ Translated from Prikladnaya Mekhanika, Vol. 41, No. 10, pp. 12–51, October 2005.     

PERSPECTIVES IN MECHANICS OF HETEROGENEOUS SOLIDS

The Microand Nano-mechanics Working Group of the Chinese Society of Theoretical and Applied Mechanics organized a forum to discuss the perspectives,trends,and directions in mechanics of heterogeneous materials in January 2010.The international journal,Acta Mechanica Solida Sinica,is devoted to all fields of solid mechanics and relevant disciplines in science,technology,and engineering,with a balanced coverage on analytical,experimental,numerical and applied investigations.On the occasion of the 30 th anniversary of Acta Mechanica Solida Sinica,its editor-in-chief,Professor Q.S.Zheng invited some of the forum participants to review the state-of-the-art of mechanics of heterogeneous solids,with a particular emphasis on the recent research development results of Chinese scientists.Their reviews are organized into five research areas as reported in different sections of this paper.§I firstly brings in focus on microand nano-mechanics,with regards to several selective topics,including multiscale coupled models and computational methods,nanocrystal superlattices,surface effects,micromechanical damage mechanics,and microstructural evolution of metals and shape memory alloys.§II shows discussions on multifield coupled mechanical phenomena,e.g.,multi-fields actuations of liquid crystal polymer networks,mechanical behavior of materials under radiations,and micromechanics of heterogeneous materials.In §III,we mainly address the multiscale mechanics of biological nanocomposites,biological adhesive surface mechanics,wetting and dewetting phenomena on microstructured solid surfaces.The phononic crystals and manipulation of elastic waves were elaborated in §IV.Finally,we conclude with a series of perspectives on solid mechanics.This review will set a primary goal of future science research and engineering application on solid mechanics with the effort of social and economic development.     

Birkhoff力学的研究进展

Birkhoff力学是Hamilton力学的一个自然发展,是分析力学发展的一个新阶段,它广泛应用于力学、物理学和工程.本文总结Birkhoff力学的形成和发展,特别是近二十年所取得的成就.首先,从Birkhoff的《动力系统》中的有关段落开始,叙述Birkhoff力学的起源.其次,叙述这个力学的基本原理——Pfaff-Birkhoff原理以及这个力学的基本方程——Birkhoff方程的形成和发展.第三,简述Birkhoff力学的一些专门问题,包括约束Birkhoff系统,Birkhoff方程的积分方法,Birkhoff动力学逆问题,Birkhoff方程的运动稳定性,Birkhoff系统的几何方法,Birkhoff系统的全局分析等.最后,对Birkhoff力学的未来研究提出一些建议.      

ON THE CULTIVATION OF UNDERGRADUATE STUDENTS MAJORING MECHANICS BASED ON THE IDEA OF UNIVERSITY

21世纪信息技术、微纳米技术和生物技术等新兴领域的高速发展给力学专业的人才培养带来了机遇与挑战。本文简单介绍了高等教育的基本理念与发展及其在中国的演变。通过分析现阶段社会发展的需求和力学发展的趋势,阐述了力学本科的培养目标应该是具有宽广的人文素养和深厚的专业知识的创新型人才。本文结合上海大学二十余年来理论与应用力学本科人才培养的实际情况,对实现这一目标提出了几点参考建议。     

On new symplectic elasticity approach for exact bending solutions of rectangular thin plates with two opposite sides simply supported

This paper presents a bridging research between a modeling methodology in quantum mechanics/relativity and elasticity. Using the symplectic method commonly applied in quantum mechanics and relativity, a new symplectic elasticity approach is developed for deriving exact analytical solutions to some basic problems in solid mechanics and elasticity which have long been bottlenecks in the history of elasticity. In specific, it is applied to bending of rectangular thin plates where exact solutions are hitherto unavailable. It employs the Hamiltonian principle with Legendre’s transformation. Analytical bending solutions could be obtained by eigenvalue analysis and expansion of eigenfunctions. Here, bending analysis requires the solving of an eigenvalue equation unlike in classical mechanics where eigenvalue analysis is only required in vibration and buckling problems. Furthermore, unlike the semi-inverse approaches in classical plate analysis employed by Timoshenko and others such as Navier’s solution, Levy’s solution, Rayleigh–Ritz method, etc. where a trial deflection function is pre-determined, this new symplectic plate analysis is completely rational without any guess functions and yet it renders exact solutions beyond the scope of applicability of the semi-inverse approaches. In short, the symplectic plate analysis developed in this paper presents a breakthrough in analytical mechanics in which an area previously unaccountable by Timoshenko’s plate theory and the likes has been trespassed. Here, examples for plates with selected boundary conditions are solved and the exact solutions discussed. Comparison with the classical solutions shows excellent agreement. As the derivation of this new approach is fundamental, further research can be conducted not only on other types of boundary conditions, but also for thick plates as well as vibration, buckling, wave propagation, etc.     

井下管柱力学与控制方法若干研究进展

关于井下管柱力学的研究迄今已有七十多年的历程, 取得了许多重要的研究成果, 并主要在油气井工程中获应用实效. 然而, 由于井眼约束和作业工况的复杂性, 目前仍未能够全面而准确地揭示井下管柱在狭长井眼内的复杂力学行为, 导致相关工程设计控制方法难以解决好实际遇到的许多复杂问题. 本文回顾了井下管柱力学的整体发展脉络, 重点讨论井下管柱的静力学变形控制方程, 然后针对井下管柱力学中的几个重要科学问题, 包括井下管柱屈曲、井下管柱摩阻磨损、井下管柱安全作业极限和底部钻具组合力学特性及其相应的设计控制方法等, 分别简要介绍了相关研究进展、最新研究成果及存在的一些问题等, 并在一定程度上进行了总结与展望, 以期为井下管柱力学与控制方法的创新发展并促进油气井工程技术进步提供有益参考.      

Phonon dispersion analysis of carbon nanotubes based on inter-belt model and symplectic solution method

The objective of the study is to develop a totally new theory and structural mechanics model for phonon dispersion analysis of carbon nanotubes. The fundamental theory and computational algorithm for phonon dispersion analysis of carbon nanotubes are developed based on the symplectic theory and algorithm established in applied mechanics in recent years. Carbon nanotubes are simulated by two kinds of structural mechanics models, i.e. the conventional sub-structure model and the inter-belt model. The variational principle for wave dissipation analysis of periodic structure is given on the basis of the symplectic-mathematical theory. Numerical examples are carried out to demonstrate the validity of the theory and algorithm developed. By the comparison of the results obtained by the two kinds of structural mechanics models, it can be found that the inter-belt model has more advantages than the conventional sub-structure model in the calculation of phonon spectra of nanotubes. As a basic research work, the present study illustrates well the potential of the symplectic-mathematical theory as well as the inter-belt model and is valuable for the further research in computational nanomechanics.