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171.
域外奇点法在弹性力学中的应用   总被引:1,自引:0,他引:1  
本文将域外奇点法推广应用于弹性力学问题,求解了扭转问题,平面弹性问题和平面弯曲问题.计算表明,这种方法简单,计算时间短,精度高。  相似文献   
172.
An algorithm for solving plane boundary-value problems of elasticity for a rectangular domain is expounded. The algorithm is based on a complex-valued representation of the general solution to the differential equations of the plane problem and on the use of Lagrange polynomials to satisfy the boundary conditions. The algorithm can quite easily be implemented in a computer program. This is probably the simplest way of solving boundary-value problems of this class __________ Translated from Prikladnaya Mekhanika, Vol. 42, No. 1, pp. 97–102, January 2006.  相似文献   
173.
We develop a constitutive model of paper's in-plane biaxial tensile response accounting for the elastic–plastic hardening behavior, and its orthotropic character. The latter aspect is motivated by machine-made papers, which, in contrast to isotropic laboratory handsheets, are strongly oriented. We focus on modeling paper's response under monotonic loading, this restriction allowing us to treat the elastic-plastic response as a physically nonlinear elastic one. A strain energy function of a hyperbolic tangent form is developed so as to fit the entire range of biaxial and uniaxial experiments on a commercial grade paper. This function may then be introduced as the free energy function into a model based on thermomechanics with internal variables.  相似文献   
174.
本文研究了考虑横向剪切影响的弹性厚壁圆柱壳的静力问题。利用变分原理得到平衡微分方程组和相应的边界条件。将平衡方程组归并成一个高阶微分方程,用数值法求出它的特征根,得到问题的解。  相似文献   
175.
THE EXACT INTEGRAL EQUATION OF HERTZ’S CONTACT PROBLEM   总被引:2,自引:0,他引:2  
This paper presents the exact integral equation of Hertz‘s contact problem,which isobtained by taking into account the horizontal displacement of points in the contactedsurfaces due to pressure.  相似文献   
176.
The longitudinal and transverse components of deformation of the surface of a flat layer of a viscoelastic material glued onto a solid base under the action of a traveling pressure wave are determined. The coating compliance is described by two components corresponding to two components of surface displacement. The dimensionless compliance components depend only on the viscoelastic properties of the material, the ratio of the wave length to the layer thickness λ/H, and the ratio of the wave velocity to the velocity of propagation of shear oscillations V/C t 0 . Data on the dynamic compliance are presented for 0.3 < λ/H < 30 and 0.1 < V/C t 0 < 10. The compliance is demonstrated to be determined by its absolute value and by the phase lag of strain from pressure. The effect of viscous losses in the material and compressibility of the latter on the dynamic compliance is analyzed. An anomalous behavior of the compliance with the wave velocity being greater than a certain critical value is explained. __________ Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 48, No. 2, pp. 90–97, March–April, 2007.  相似文献   
177.
A theory of elasticity for the bending of orthogonal anisotropic beams has been developed by analogy with the special case, which can be obtained by applying the theory of elasticity for bending of transversely isotropic plates to the problems of two deminsions. In this paper, we present a method to solve the problems of bending of orthogonal anisotropic beams and a new theory of the deep-beam whose ratio of depth to length is larger. It is pointed out that Reissner's theory to account for the effect of transverse shear deformation is not very approximate in the components of stress,  相似文献   
178.
三维裂纹问题的高精度数值解法   总被引:7,自引:3,他引:7  
提出了一种求解三维均质弹性体中任意形状平片裂纹问题超奇异积分方程组的Chebyshev多项式数值解法。数值计算结果表明:文中方法不仅收敛快,而且精度高。  相似文献   
179.
复变量移动最小二乘法及其应用   总被引:7,自引:2,他引:7  
提出了复变量移动最小二乘法,并详细讨论了基于正交基函数的复变量移动最小二乘 法. 然后,将复变量移动最小二乘法和弹性力学的边界无单元法结合,提出了弹性力学的复 变量边界无单元法,推导了相应的公式,并给出了数值算例. 基于正交基函数的复变量移动 最小二乘法的优点是不形成病态方程组、精度高,所形成的无网格方法计算量小. 复变量边 界无单元法是边界积分方程的无网格方法的直接列式法,容易引入边界条件,且具有更高的 精度.  相似文献   
180.
The problem of simplifying the nonlinear hereditary elasticity relations is considered for strongly anisotropic materials such as fiber-reinforced composites. This is done using their property that the material stiffness is high along the reinforcement and is low in the cross-sectional direction. The material is considered transversally isotropic. The simplification is performed by analyzing asymptotic representations of creep relations. Relations of various degrees of accuracy for various types of composites and stress states are obtained. __________ Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 46, No. 3, pp. 120–127, May–June, 2005.  相似文献   
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