【摘要】 通过对耦合的波动方程和调和方程解耦 ,用自模拟方法研究了压电材料中反平面裂纹的自相似扩展问题 .研究表明 :对反平面问题 ,介质内的耦合场与裂纹扩展速度有关 ,在裂纹尖端有r-1 2 阶的奇异性 ;动态应力强度因子与电位移载荷有关 ,与静态结论不同 ;电位移强度因子与机械载荷无关 ,与静态结果的表达形式一致更多还原

【Abstract】 The governing equations of the electro elastic dynamic problem for the piezoelectric medium are coupled. However, for the antiplane problem, the coupling effect in the wave equation and Laplace equation can be eliminated (Bleustein, 1968). In this paper, two independent quasi stress problems are proposed by decoupling the governing equations. The anti plane problem of crack symmetric growth in the piezoelectric medium is analysed using the self similar method (Cherepanov, 1974), and the closed form solutions and the intensity factors at the crack tip are obtained. It is shown that the coupled field depends on the speed of the crack propagation. Moreover, the expression of the electric displacement intensity factor is consistent with the static result (Pak, 1990).更多还原