裂纹前端局部加强板的韧性断裂分析(英文)

Ductile Fracture Analysis on a Cracked-Stiffened Plate

对局部加强含裂纹板的弹塑性断裂问题进行了分析计算。建立了裂纹前端局部加强的裂纹板弹塑性分析的Dug-dale模型,以裂纹尖端开口位移CTOD为断裂参数,就加强复板位置、结构参数及加强复板与裂纹板材料参数等因素对结构止裂性能的影响进行了分析计算。结果表明,在裂纹前端进行局部加强使裂纹尖端的塑性区长度减小,且降低了裂纹尖端的开口位移CTOD,能有效地阻止裂纹扩展。提高加强复板相对刚度有利于改善裂纹尖端状态,提高结构的承载能力。

Solutions to the ductile fracture are presented for cracked-stiffened plate subjected to mode I loading. The Dugdale model of a crack is constructed. The Dugdale solutions for the plastic zone size and CTOD （Crack Tip Opening Displacement） are obtained by using a discrete cracked- stiffened plate model. A parametric study involving the stiffener location, stiffener relative stiffness is reported.The arresting efficiency is studied for a stiffener on retarding the growth of an elasticplastic crack.The numerical results show that the CTOD decrease significantly with the stiffener relative stiffness increasing.h is also shown that a stiffener has only a localized effect.The stiffener does not have much effect until the crack tip gets close to it.