Finite-part integral and boundary element method to solve flat crack problems

Using the Somigliana formula and the concepts of finite-part integral, a set of hypersingular integral equations to solve the arbitrary fiat crack in three-dimensional elasticity is derived and its numerical method is then proposed by combining the finitepart integral method with boundary element method. In order to verify the method, several numerical examples are carried out. The results of the displacement discontinuities of the crack surface and the stress intensity factors at the crack front are in good agrernent with the' theoretical solutions.     

METHOD OF STRONGLY SINGULAR INTEGRAL EQUATION FOR THE TORSION OF CYLINDER WITH EDGE CRACK

From the dislocation type solution of the torsion of single crack,by using the concept of finite part integrals,we reduce the torsion problem of cylinder with a single crack into an integral equation with strong singularity.The numerical method is also obtained and several numerical examples are calculated successfully at the end of this paper.     

关于基础力学课程教学改革的思考

基于对我国基础力学课程教学现状的思考,针对教学内容、专业体制和师资培训等方面提出了若干改革设想．     

Interaction between crack and elastic inclusion

ＩＮＴＥＲＡＣＴＩＯＮＢＥＴＷＥＥＮＣＲＡＣＫＡＮＤＥＬＡＳＴＩＣＩＮＣＬＵＳＩＯＮＺｈａｎｇＭｉｎｇ－ｈｕａｎ（张明焕）,ＴａｎｇＲｅｎ－ｊｉ（汤任基）（ＳｈａｎｇｈａｉＪｉａｏｔｏｎｇＵｎｉｖｅｒｓｉｔｙ,Ｓｈａｎｇｈａｉ,２０００３０,Ｐ．Ｒ．...     

用样条边界元与奇异积分方程法联合求解多裂纹柱体的扭转

通过间解的分离，本文将径向多裂纹柱体的导曲函两个调和函数表示，使问题归为解一组混混合型积分方程。针对方程的特点，本文联合使用三次样条边界法与奇异积分方程的数值方法对所得方程建立了数值法，并对裂纹相交情形作了特殊处理。最后对工程中感兴趣的一些典型的多裂纹柱体的扭转作了例题计算，结果表明，本文方法具有收敛快，精度高的特点。     

The Crack-Inclusion Interaction and the Analysis of Singularity for the Horizontal Contact

ＩｎｔｒｏｄｕｃｔｉｏｎＷｈｉｌｅｗｅｓｔｕｄｙｔｈｅｓｔｒｅｎｇｔｈａｎｄｔｈｅｃｒａｃｋｏｆｐｒａｃｔｉｓｉｎｇｃｏｍｐｏｎｅｎｔｓ,ｔｈｅｍａｔｅｒｉａｌｄｅｆｅｃｔｉｏｎｓｈｏｕｌｄｂｅｃｏｎｓｉｄｅｒｅｄ .ＩｎｔｈｅｏｐｉｎｉｏｎｓｏｆＣｒａｃｋＭｅｃｈａｎｉｃｓ,ｔｈｅｍａｔｅｒｉａｌｄｅｆｅｃｔｉｏｎｃａｎｂｅｒｅｄｕｃｅｄｔｏｐｌａｎａｒｃｒａｃｋｓａｎｄｉｎｃｌｕｓｉｏｎｓ.Ｂｅｓｉｄｅｓ,ｔｈｅｐｒｏｂｌｅｍｏｆｓｈｏｒｔ＿ｆｉｂｅｒｃｏｍｐｏｓｉｔｅｍａｔｅｒｉａｌｓｕｃｈａｓ…     

AN ANALYSIS OF A RADIAL CRACK IN A REINFORCED HOLLOW CYLINDER

Using the Michell solution and the crack solution, the integral equation of a radialcrack in a hollow cylinder reinforced on its outer boundary is derived. The effects of thereinforced membrane on the crack are analysed and several numerical results are presentedherein.     

用牛角芯棒推制弯管的塑性分析

采用牛角芯棒推制弯管,是一项有效的塑性成型技术.本文在总结实验资料的基础上建立了用于分析此类问题的力学模型,经对变形速度场作了某些假定后把问题化成了一个典型的Goursat问题,并用逐次逼近法求得了解答.Swift的直锥管塑性解是本文的特殊情形.文中对一种典型的牛角芯棒作了数值计算,所得结果与实验符合较好.在此基础上提出了一些有用的近似公式.本文的结果对于分析弯管推制的机理以及其他有意义的理论问题提供了一个基础,对于弯管推制的设计也有参考价值.     

刚性线夹杂与弹性圆夹杂的相互作用

本文将刚性线夹杂与弹性圆夹杂的相互作用，归为解一个标准的柯西型奇异积分方程，获得了刚性夹杂端点的应力强度因子及夹杂的界面应力．