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1.
各向异性材料中共线刚性线夹杂的纵向剪切问题   总被引:8,自引:2,他引:6  
本文研究各向异性材料中共线刚性线夹杂,(有时称作“硬裂纹”或“反裂纹”问题)的纵向剪切问题。利用复变函数方法,提出了一般问题的公式和某些实际重要问题的封闭形式解,考察了刚性线端点附近的应力分布.从本文解答的特殊情形,可以直接导出各向同性材料相应问题的公式和结果,包括某些已有的结果 ̄[7].  相似文献   

2.
研究了各向异性双材料中匀速运动螺型位错与界面刚性线的干涉问题.运用Riemann Schwarz解析延拓技术与复势函数奇性主部分析方法,获得了该问题的一般弹性解答,求出了界面含一条和两条刚性线情况下的封闭形式解,并给出了刚性线尖端的应力强度因子和作用于运动位错上的像力的显式表达式.结果表明,位错速度增大可以削弱位错对应力强度因子的反屏蔽效应;位错速度越大,位错平衡点越靠近刚性线,退化结果与已有的解答完全吻合.  相似文献   

3.
研究了圆弧形界面刚性线夹杂的平面弹性问题.集中力作用于夹杂或基体中的任意点,并且无穷远处受均匀载荷作用.利用复变函数方法,得到了该问题的一般解答.当只含一条界面刚性线夹杂时,获得了分区复势函数和应力场的封闭形式解答,并给出刚性线端部奇异应力场的解析表达式.结果表明,在平面荷载下界面圆弧形刚性线夹杂尖端应力场和裂纹尖端相似具有奇异应力振荡性.对无穷远加载的情况,讨论了刚性线几何条件、加载条件和材料失配对端部场的影响.  相似文献   

4.
圆形界面刚性线夹杂的反平面问题   总被引:1,自引:1,他引:0  
研究了在反平面集中力和无穷远纵向剪切作用下,不同弹性材料圆形界面上有多条刚性线夹杂的问题.运用Riemann-Schwarz解析延拓技术与复势函数奇性主部分析方法,首次获得了该问题的一般解答,求出了几种典型情况的封闭解,并给出了刚性线夹杂尖端的应力场分布A·D2结果表明,在反平面加载的情况下圆形界面刚性线夹杂尖端应力具有平方根奇异性,无奇异性应力振荡;应力场与刚性线夹杂的形状,加载方式和材料性质有关.退化结果与已有的解答完全吻合.  相似文献   

5.
探讨了横观各向同性压电体平面问题中裂尖的非奇异应力项.利用叠加原理和Plemelj公式,通过求解Rieman-Hilbert问题得到非奇异应力项.结果表明弹性常数,压电及介电常数影响着非奇异应力项的值.当压电材料退化为各向异性材料时,该值与在各向异性材料时所得结果一致.  相似文献   

6.
无限横观各向同性弹性圆柱中刚性圆盘的扭转振动   总被引:1,自引:1,他引:0  
分析了无限横观各向同性弹性圆柱中,刚性圆盘的扭转振动问题.绘制的图形显示了材料的各向异性性质对应力强度因子的影响.  相似文献   

7.
通过利用八维Stroh公式以及共形映射、解析延拓和奇点分析技术,获得了对一压电基体中已部分脱开的刚性导体椭圆夹杂二维问题的闭合形式全场解答。也推导了一些新的恒等式和求和式,通过这些恒等式及求和式可获得沿界面应力和电位移分布以及刚性夹杂转动的实形式表示。正如所预料的,在脱开界面的端部应力及电位移显现出与在压电材料Griffith界面裂纹的研究中所发现的相似的奇异行为。最后也给出了几个算例以展示所得到解答的一般性以及各种载荷条件、几何参数和机电常数等对界面处应力及电位移分布的影响。  相似文献   

8.
应用富里叶积分变换方法将裂纹边值问题化为对偶积分方程组,再用定积分变换法将问题进一步化为奇异积分方程组,求得了双材料各向异性弹塑性介质中周期性界面裂纹反平面问题的封闭形式解,并作为特例讨论了各向同性双材料问题、各向异性单一材料问题及各向同性—各向异性双材料问题.结果表明:裂纹尖端前沿的塑性区尺寸、裂纹的张开位移(COD)均决定于两种材料流动极限中的较小者及裂纹的长度和相邻两裂纹的间距,此外,COD还与材料模量有关.  相似文献   

9.
压电螺型位错和含界面裂纹圆形夹杂的电弹干涉效应   总被引:3,自引:0,他引:3  
研究了在无穷远反平面剪切和面内电场共同作用下压电材料基体中一个压电螺型位错与含界面裂纹圆形弹性夹杂的电弹耦合干涉作用.运用复变函数方法,获得了该问题的一般解答.作为典型算例,求出了界面含一条裂纹时,基体和夹杂区域复势函数的封闭形式解以及裂纹尖端应力和电位移场强度因子.应用扰动技术和广义Peach-Koehler公式,导出了位错力的解析表达式.数值结果表明,界面裂纹对压电螺型位错与夹杂的干涉具有强烈扰动效应,当裂纹长度达到临界值时,可以改变其干涉机理.同时,分析说明压电材料中软夹杂可以排斥基体中的位错.  相似文献   

10.
反平面集中力作用下不同材料界面共线裂纹问题   总被引:4,自引:0,他引:4  
本文研究在反平面集中力作用下,不同弹性材料界面上的共线裂纹问题.运用复变函数的解析延拓方法并结合对奇性主部的分析,获得了一般解;求出了几种典型情况的封闭解;算出了应力强度因子.本文解答的若干特殊情形,与前人成果吻合.通过比较,我们发现,在局部对称加载下,本文结果与同种材料的相应解答完全相同.  相似文献   

11.
We obtain a system of singular integral equations for the problem of thermoelastic contact of two dissimilar anisotropic half-planes with a system of thermally isolated gaps on the line of contact. Analysis of the contact interaction parameters was carried out for half-planes made of identical materials using the condition that on the surface of one of them there is a symmetric hole of prescribed shape. We give a scheme for numerical solution of the problem for holes of different profiles. Translated fromMatematichni Metodi i Fiziko-mekhanichni Polya, Vol. 40, No. 1, 1997, pp. 117–124.  相似文献   

12.
This study is concerned with the determination of the elastic behaviour of two dissimilar materials containing a single and two interacting inhomogeneities near the interface using a novel finite element. The general form of the element, which is constructed from a cell containing a single circular inhomogeneity in a surrounding matrix, is derived explicitly in a series form using the complex potentials of Muskhelishvili. The strength of the adopted eight-noded plane element lies in its ability to treat periodically and/or arbitrarily located multiple inhomogeneities in dissimilar materials accurately and efficiently.

Pertinent stress distributions are examined to illustrate the importance of the elastic properties of the dissimilar materials, the distance between their interface and the inhomogeneities and the direction of the externally applied load with respect to that interface upon the resulting stress field. The results of our work assist in defining the design parameters which govern the elastic behaviour of the examined problem. This problem relates to fibre reinforcement in advanced composite materials, second phase particles in traditional materials and plates stiffened with stringers commonly used in the aerospace and automotive fields.  相似文献   


13.
Many classical rigid perfectly/plastic solutions cannot be extended to more complicated rigid plastic materials, such as rigid plastic hardening materials and rigid viscoplastic materials. The present paper reveals sources of this difficulty in the case of flow of rigid viscoplastic material through infinite converging rough wedge-shaped and axisymmetric channels. Two types of viscoplastic models without strain hardening are considered, with and with no saturation stress. The maximum friction law is adopted at the friction surface. Qualitative features of the solutions are compared to those occurring in compression of a rigid plastic layer between rough, parallel plates. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

14.
A theoretical basis is provided for the experimental method of determining the elastic and strength properties of materials by stretching ring specimens with a pair of rigid half-disks. The equilibrium equations of the plane problem for an anisotropic ring with mixed boundary conditions are solved by means of an expansion in Fourier series with respect to the circumferential coordinate. Numerical results obtained on a computer are analyzed. The dependence of the circumferential stress concentration coefficient on various parameters is investigated.Moscow Power Engineering Institute. Translated from Mekhanika Polimerov, No. 6, pp. 1113–1116, November–December, 1970.  相似文献   

15.
The contact problem on interaction of rigid stamps with anisotropic plates with regard to wear and the corresponding frictional heating is considered. The procedure developed is based on the reduction of the governing equation to a system of Volterra integral equations of the second kind. The numerical analysis allows us to study the effects of both the anisotropic thermoelastic characteristics of materials and the nature of the interaction of the contact-pair elements on the wear process.Pidstryhach Institute of Applied Problems of Mechanics and Mathematics, National Academy of Sciences of Ukraine, Lviv, Ukraine. Translated from Mekhanika Kompozitnykh Materialov, Vol. 35, No. 3, pp. 309–318, May–June, 1999.  相似文献   

16.
应用Stroh理论,研究了两压电介质之间的刚性介电线夹杂问题。首先该问题被化为Hilbert问题,然后分别给出了压电介质内的复势函数解、夹杂内的电场解和夹杂尖端场的解析表达式。结果表明,在夹杂尖端附近,所有的场变量均呈现奇异性和振荡性,且其强度取决于介质的材料常数和无限场远处的应变。此外,结果还表明,当从夹杂内部趋近夹杂尖端时,夹杂内的电场也呈现奇异性和振荡性。  相似文献   

17.
以短纤维复合等作为工程背景,采用现有文献中单裂纹和单夹杂的基本解,对于限平项(基体)上,裂纹和线夹杂的垂直接触问题从断理解力学的角度作了研究,得到了问题的积分方程,推出了接触点的性线指数,奇性应力及以此表示的接触点附近三个区域内的应力强度因子表达式,并给出一些数值结果,可供工程实际参考。  相似文献   

18.
We derive closed-form solutions to the mixed boundary value problem of a partially debonded rigid line inclusion penetrating a circular elastic inhomogeneity under antiplane shear deformation. The two tips of the rigid line inclusion are just mutual mirror images with respect to the inhomogeneity/matrix interface, and the upper part of the rigid line inclusion is debonded from the surrounding materials. By using conformal mapping and the method of image, closed-form solutions are derived for three loading cases: (i) the matrix is subjected to remote uniform stresses; (ii) the matrix is subjected to a line force and a screw dislocation; and (iii) the inhomogeneity is subjected to a line force and a screw dislocation. In the mapped ξ-plane, the solutions for all the three loading cases are interpreted in terms of image singularities. For the remote loading case, explicit full-field expressions of all the field variables such as displacement, stress function and stresses are obtained. Also derived is the near tip asymptotic elastic field governed by two generalized stress intensity factors. The generalized stress intensity factors for all the three loading cases are derived.  相似文献   

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