伍江飞

• 1:河海大学力学与材料学院

摘要(Abstract)：

为了解决混凝土材料的断裂问题,采用扩展有限元法结合黏聚裂纹模型对混凝土非线性断裂力学行为进行模拟。在黏聚裂纹模型中,裂纹附近应力场没有奇异性,因此,基于四结点四边形单元构造了一种新的黏聚裂纹模拟的扩展有限元位移模式,并采用符号函数对所有的开裂单元(包括裂纹贯穿单元和裂尖单元)进行加强。采用类似于"弧长法"的方案求解非线性控制方程。结果表明:该加强策略解决了裂尖单元裂纹两边应力不等的问题,其裂尖位置任意,且混合单元处理方便。通过数值模拟混凝土Ⅰ型和混合型断裂问题,将模拟结果与参考解及试验结果进行比较,误差均在5%以内,验证了该方法的可靠性。该方法采用统一的符号函数进行加强,编程更为方便。

关键词(KeyWords)： 混凝土;扩展有限元法;黏聚裂纹模型;符号函数;裂纹扩展

Abstract:

Keywords:

基金项目(Foundation): 国家“十二五”科技支撑计划课题(2015BAB07B10)

作者(Author): 伍江飞

DOI: 10.13928/j.cnki.wrahe.2019.04.028

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