ABSTRACT

The complexity of Ceiba plywood damage makes prediction of onset and propagation of delamination an unavoidable problem. The aim of this work is to establish an onset criterion resulting from numerical modeling and a delamination propagation law from a series of experimental tests. Several tests have been put in place to evaluate the fracture toughness in mode I, mode II and mixed mode I+II. Numerical simulations are based on the cohesive zone model of Abaqus software to allow a precise description of the progressive damage of the delamination until the final failure. After the description of the experimental procedure, the experimental and numerical results are presented and compared. Then, the compliance method was used to calculate the critical energy release rate (G_C) and determine the resistance curve according to each mode of delamination. Finally, the response to delamination failure was represented by several propagation criteria. The comparison of these criteria was established to determine the law that best models the propagation of delamination of Ceiba plywood.

摘要

木棉胶合板损坏的复杂性使得预测分层的发生和扩展成为不可避免的问题。这项工作的目的是建立一个由数值模型和一系列实验测试得出的分层传播规律产生的起始标准。已经进行了多项测试来评估模式 I、模式 II 和混合模式 I+II 下的断裂韧性。数值模拟基于 Abaqus 软件的内聚区模型，可以精确描述分层的渐进损坏直至最终失效。在描述了实验过程之后，给出了实验和数值结果并进行了比较。然后，使用柔量法计算临界能量释放率（G _C)并根据每种分层方式确定电阻曲线。最后，对分层失败的响应由几个传播标准表示。建立这些标准的比较是为了确定最能模拟木棉胶合板分层传播的规律。