New Coalescence Criterion for Non-collinear Parallel Double Cracks

doi:10.3901/JME.2025.24.148

Abstract

Abstract: To accurately assess the structural integrity of multiple cracks, effectively addressing the interactions between cracks is crucial. This requires evaluating adjacent cracks based on the coalescence criterion：if adjacent cracks satisfy the criterion, they are merged into a single crack for assessment; otherwise, they are assessed separately as individual cracks. However, the coalescence criteria established by different countries vary, leading to divergent results when different criteria are applied. To develop a more precise coalescence criterion for double cracks, this study investigates the coalescence behavior of non-collinear parallel double cracks in homogeneous plates using a combined experimental and finite element numerical simulation approach. The experimental and numerical simulation results are compared with those derived from various international coalescence criteria, highlighting the limitations of existing standards. Based on the ratio of the horizontal distance between the double cracks to the average length of the cracks, and the ratio of the vertical distance to the length of the shorter crack, a new coalescence criterion for double cracks is proposed.

Key words: coalescence criterion, double cracks, experiment, GTN damage mode

CLC Number:

TH114

LIU Hongxia, WANG Xiaoxiao, CUI Yuanyuan, LIU Fang, YANG Jie, CHEN Haofeng. New Coalescence Criterion for Non-collinear Parallel Double Cracks[J]. Journal of Mechanical Engineering, 2025, 61(24): 148-157.

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