【摘要】 提出了一种新的弹性＿粘塑性模型用于分析Ⅰ型动态扩展裂纹尖端的应力应变场·　给出了适当的位移模式,推导了渐近方程并且给出了数值解·　分析和计算表明:对于低粘性情况,裂纹尖端场具有对数奇异性;对于高粘性情况,渐近方程无解·　分析比较表明该结果具有高玉臣提出的单参数解的所有优点,并且消除了粘性区随裂纹扩展而移动的不足·更多还原

【Abstract】 A new elastic_viscoplastic mode was proposed to analyze the stress and strain fields surrounding the tip of a propagating mode Ⅰ cracks. A proper displacement pattern was suggested and asymptotic equations were derived, and numerical solutions were illustrated. The analysis and calculation show that the crack_tip field is of logarithmic singularity for smaller viscosity, however no solution exits for large viscosity. By a careful analysis and comparison, it is found that the present results retain all merits of those given by GAO Yu_chen, while removing existing problems.更多还原