基于裂纹最大张口位移的加筋板弹塑性断裂分析

为了快速方便地求取船舶加筋板塑性性能的两个重要参数—裂纹尖端塑性区半径（Ry）和裂纹尖端张开位移（CTOD），文章提出了一种基于裂纹最大张口位移（MCOD）来确定加筋板的裂纹尖端塑性区半径和裂纹尖端张开位移的简便方法。该法基于理想弹塑性材料，以提出的裂纹最大张口位移与裂纹尖端塑性区半径及裂纹尖端张开位移的拟合函数关系为基础，考虑了模型尺寸效应、材料特性参数及外载荷的影响。文中还对不同裂纹长度、不同屈服极限条件、不同板/筋刚度比时方法的适用性进行了分析，研究表明：该方法能够消除裂纹长度、屈服极限和外载荷等因素的影响，适用于有限宽船舶加筋板的弹塑性分析。

Elasto-plastic fracture analysis of stiffened plates based on crack maximum opening displacement

In order to rapidly and conveniently evaluate the two important plastic property parameters of ship stiffened plate, i.e. the plastic-zone radius around crack tip and crack tip opening displacement (CTOD), a simple method is proposed for ship stiffened plates with central-through crack subjected to uniform uni-axial tensile loading, based on the maximum crack opening displacement (MCOD). On the basis of the fit-ted functional relationship of the MCOD and the two plastic property parameters, the influences of the model size effect, material parameters and external load are discussed in the analyses for elastic-perfectly plastic material. The applicability of this method for different crack length, yield limit condition and stiffness ratio of plate/stiffener was analyzed. The result from this research shows that the presented method can eliminate the influence of the crack length, yield stress and applied loading etc, and so is suitable to the elasto-plas-tic analysis for ship stiffened plates with finite width.