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41.
本文给出了求解一类相当普遍的三维运动接触问题的分析解法,并且把仅仅对静态接触问题成立的 定理推广到动力学情形,作了严格证明。作为例子,对接触区为椭圆的情形给出了积分形式的解,并且作了数值计算,由这些结果可以看出运动压体速度的效应。 相似文献
42.
冲击载荷下含表面裂纹圆柱壳体的动态断裂 总被引:1,自引:0,他引:1
动态载荷下含表面裂纹的有限尺寸构件的断裂问题在工程实践中有着重要意义,但由于此类问题非常复杂,目前还不能求得解析解。本文针对含轴向半椭圆盘状表面裂纹的圆柱壳体,应用有限元法研究了动态载荷下其断裂问题,计算了动态应力强度因子与静态应力强度因子的比值KdIyn(t)/KsIta。从计算结果可以得出,比值KdIyn(t)/KsIta与结构和裂纹的尺寸有关,而与冲击载荷的大小无关。本文所得结果在一定程度上揭示了圆柱壳体表面、裂纹面、物质惯性和弹性波的相互作用及其对动态断裂的影响。 相似文献
43.
Based on the displacement potential functions, the elastic analysis
of a mode II crack in an icosahedral quasicrystal is performed by
using the Fourier transform and dual integral equation theory. By the
solution, the analytic expressions for the displacement field and
stress field are obtained. The asymptotic behaviours of the phonon
and phason stress fields around the crack tip indicate that the
stresses near the crack tip exhibit a square root singularity. The
most important physical quantities of fracture theory, crack stress
intensity factor and energy release rate, are evaluated in an
explicit version. 相似文献
44.
Because exact analytic solution is not available,we use double expansion and boundary collocation to construct an approximate solution for a class of two-dimensional dual integral equations in mathematical physics.The integral equations by this procedure are reduced to infinite algebraic equations.The accuracy of the solution lies in the boundary collocation technique.The application of which for some complicated initial- boundary value problems in solid mechanics indicates the method is powerful. 相似文献
45.
A method for analyzing the elasticity problem of cubic quasicrystal is developed. The axisymmetric elasticity problem of cubic quasicrystal is reduced to a single higher-order partial differential equation by introducing a displacement function. As an example, the solutions of elastic field of cubic quasicrystal with a penny-shaped crack are obtained, and the stress intensity factor and strain energy release rate are determined. 相似文献
46.
PERTURBATION METHOD SOLVING ELASTIC PROBLEMS OF ICOSAHEDRAL QUASICRYSTALS CONTAINING A CIRCULAR CRACK 下载免费PDF全文
Perturbation method for solving elastic three-dimensional (3D) problems for 3D icosahedral quasicrystals is proposed. Considering an infinite 3D icosahedral quasicrystal weakened by a circular crack, we obtain the uniformly valid asymptotic solutions up to O(R2) for the mode I loading, where R is the elastic constant of phonon-phason coupling. 相似文献
47.
IntroductionThediscoveryofquasicrystalaround 1 984 [1,2 ,3]issignificantbreakthroughforcondensedmatterphysicsinrecentyears.Thequasiperiodicsymmetryofsolidpresentsgreattheoreticalsignificance .Numerousquasicrystallinematerialswithstablepropertywereproduced ,thi… 相似文献
48.
49.
平面十次对称准晶中Ⅱ型Briffith裂纹的求解 总被引:1,自引:0,他引:1
应用应力函数法,求解了二维十次对称准晶中的Ⅱ型Griffith裂纹问题。特别是把二维准晶的弹性力学问题分解成一个平面应变问题与一个反平面问题的叠加,通过引入应力函数,把平面应变问题的十八个弹性力学基本方程简化成一个八阶偏微分方程,并且求出了其在Ⅱ型Griffith裂纹情况的混合边值问题的解,所有的应力分量和位移分量都用初等函数表示出来,并且由此得出了准晶中Ⅱ型Griffith裂纹问题的应力强度因子和能量释放率。 相似文献
50.
弹性半平面中的斜边界裂纹问题 总被引:2,自引:0,他引:2
讨论了一群性半平面无限体中含有一斜烈纹的静力学问题,研究中以断裂力学原理为基础,采用了复变函数的方法,将原问题化为一组解析函数边值问题的求解。文中通过分析函数法以及应用Riemann-Hilbert(R-H)边值问题的一般理论,给出了所研究问题的解析解,并且给出了此问题的应力强度因子K1,K1的显式形式,此外,裂纹上的位移发生的错动可以得以进一步的讨论,文中的结论对地学的研究有一定的应用价值。 相似文献