We present a phase field based MITC4+ shell element formulation to simulate fracture propagation in thin shell structures. The employed MITC4+ approach renders the element shear- and membrane- locking free, hence providing high-fidelity fracture simulations in planar and curved topologies. To capture the mechanical response under bending-dominated fracture, a crack-driving force description based on the maximum strain energy density through the shell-thickness is considered. Several numerical examples simulating fracture in flat and curved shell structures are presented, and the accuracy of the proposed formulation is examined by comparing the predicted critical fracture loads against analytical estimates.

中文翻译：

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基于MITC4+方法的薄壳单元脆性断裂相场建模

我们提出了一种基于相场的 MITC4+ 壳单元公式来模拟薄壳结构中的裂缝扩展。所采用的 MITC4+ 方法使单元无剪切锁定和膜锁定，从而在平面和弯曲拓扑中提供高保真断裂模拟。为了捕捉弯曲主导断裂下的机械响应，考虑了基于通过壳厚度的最大应变能量密度的裂纹驱动力描述。介绍了几个模拟平壳和弯曲壳结构断裂的数值例子，并通过将预测的临界断裂载荷与分析估计值进行比较来检查所提出的公式的准确性。