两非均匀半平面粘结的非均匀平面的裂纹问题*

本文对两个非均匀半平面粘结的非均匀平面的裂纹问题作了分析,文中假定两种材料的泊松比v相同,但杨氏模量随坐标x按不同形式的指数函数变化.本文使用非均匀平面问题的单裂纹解及富氏变换方法, 使问题归为一个柯西型奇异积分方程,最后对应力强度因子的计算给出了若干数值例子.     

Numerical investigation of three-dimensional viscous incompressible flows in divergent curved channels and turbulent model study

In order to make the numerical calculation of viscous flows more convenient for the flows in channel with complicated profile governing equations expressed in the arbitrary curvilinear coordinates were derived by means of Favre density- weighted averaged method, and a turbulent model with effect of curvature modification was also derived. The numerical calculation of laminar and turbulent flows in divergent curved channels was carried out by means of parabolized computation method. The calculating results were used to analyze and investigate the aerodynamic performance of stator cascades in compressors preliminarily.     

A crack emanating from the tip of bonded dissimilar materials

1.IntroductionBondedstructurescanbewidelyfoundindifferentareas,suchasweldedpressurevessels,reinforcedconcretemembers,groutingsoftfoundationandsolidrocketpropellants.etc.Thestudy'ofthesingularityofbondedstructuresisespeciallyimp6rtantnotonlyforsafedesignbutalsoforconstruction.DeinpseyandSinclairl61studiedthegeneraleaseofN-materialcompositewedges,andprovedthat'ingeneralthereexistsstresssingularitynearthetipofthewedges,andtheorderofthesingularitydependsontheelasticconstantsandthelocalgeometry.Fo…     

含主应力轴旋转的土体一般应力应变关系

本文利用矩阵理论,分析了使主应力轴产生旋转的应力增量特性,并将一般应力增量分解为与应力共主轴部分及使之产生旋转部分。据此,将含主应力轴旋转的复杂三维问题简化为三维应力应变共轴问题和三主值不变绕某一主轴旋转问题的结合,大大简化了分析的难度。文中还结合有关模型给出了一般三维问题的具体计算方法。     

混凝土材料裂纹尖端损伤带尺寸特性*

本文采用作者研究各向异性材料裂纹尖端塑性区特性的分析方法,研究了混凝土材料裂纹尖端损伤带尺寸特性.基于单轴应力假定,考虑了混凝土材料的非线性软化特性等影响,提出用两种分析模型:即能量模型和断裂模型来分别讨论.最后,还对这些模型作了比较.     

Coordinates of principal stresses for elastic plane problem

I.IntroductionInelasticmechanics,thereisakindofproblemsthatcouldbesolveddirectlybyequilibriumequations,i.e.,whenal1oftheboundaryconditionsaretheknownstressesorforcessuchasthestressfunction.Becausestressfunctionsmustsatisfyharmonicequationorbi-harmonicequa…     

Electro-elastic green's functions for a piezoelectric half-space and their application

I.IntroductionItiswell'knownthatoneofthemostpowerfultoolsinlinearfieldtheoriesistheGreen'sfunction.Fore1asticity,considerableresearchcanbefoundintheliterature.However,theGreen'sfunctionforpiezoe1ectricityisratherlimitedduetotheanisotropyandelectromechanic…     

The Saint-Venant problem of plane bar under an axial force

I.PrefaceAsweknow,theSaint-Venanttheoryisawell-knownanduniversallyacceptedtheory.Butasoneofthegeneraltheoriesofelasticmechanics,itisnotprovedperfectely,althoughitistestedbyexperiments.Infact,onlyforthesimplestproblemofelasticity,itisnoteasytofindanalytics…     

带裂纹层合板能量释放率分析

为了进一步了解裂纹尖端应力场的特性,本文对复合材料层合板的界面裂纹作了分析.文中强调了能量释放率分量存在的条件,并给出能量释放率分量和应力强度因子间的关系式.结合经典板理论的分析结果,根据外荷作用及某些几何参数和材料多数,导出了一般复合材料层合板的应力强度因子的封闭形式解.为了得到在一般荷载条件下能量释放率的分量,必须分别确定模型混合参数Ω,文中讨论了确定参数Ω的方法,最后,应用本文方法于几种不同种类的复合材料层合板,证明其结果可应用于工程实践.     

不可压缩橡胶类材料裂纹尖端应力应变场*

本文对平面应变情况下不可压缩橡胶类材料裂纹尖端弹性场进行了有限变形分析.裂纹尖端场被分为收缩区和扩张区.借助于新的应变能函数和变形模式,推出了尖端场各区的渐近方程,得到了尖端场的完整描述.本文对奇异性作了讨论,得到了不可压缩橡胶类材料裂纹尖端应力及应变分布曲线,揭示了裂纹尖端应力应变场的特性.