Understanding crack propagation in structures subjected to fluid loads is crucial in various engineering applications, ranging from underwater pipelines to aircraft components. This study investigates the dynamic response of structures, including their damage and fracture behaviour under hydrodynamic load, emphasizing the fluid-structure interaction (FSI) phenomena by applying Smoothed Particle Hydrodynamics (SPH). The developed framework employs weakly compressible SPH (WCSPH) to model the fluid flow and a pseudo-spring-based SPH solver for modelling the structural response. For improved accuracy in FSI modelling, the $\delta$-SPH technique is implemented to enhance pressure calculations within the fluid phase. The pseudo-spring analogy is employed for modelling material damage, where particle interactions are confined to their immediate neighbours. These particles are linked by springs, which don't contribute to system stiffness but determine the interaction strength between connected pairs. It is assumed that a crack propagates through a spring connecting a particle pair when the damage indicator of that spring exceeds a predefined threshold. The developed framework is extensively validated through a dam break case, oscillation of a deformable solid beam, dam break through a deformable elastic solid, and breaking dam impact on a deformable solid obstacle. Numerical outcomes are subsequently compared with the findings from existing literature. The ability of the framework to accurately depict material damage and fracture is showcased through a simulation of water impact on a deformable solid obstacle with an initial notch.

翻译：理解承受流体载荷结构中的裂纹扩展对于从水下管道到飞机部件等各类工程应用至关重要。本研究通过应用光滑粒子流体动力学(SPH)方法，着重探究流固耦合(FSI)现象，研究结构在流体动力载荷下的动态响应，包括其损伤和断裂行为。所建立的框架采用弱可压缩SPH(WCSPH)模拟流体流动，并采用基于伪弹簧的SPH求解器模拟结构响应。为提升流固耦合建模精度，采用$\delta$-SPH技术增强流体相压力计算。材料损伤建模采用伪弹簧类比方法，其中粒子相互作用仅限于其直接邻域。这些粒子通过弹簧连接，弹簧虽不贡献系统刚度，但决定连接对之间的相互作用强度。假设当连接粒子对的弹簧损伤指标超过预设阈值时，裂纹通过该弹簧扩展。通过溃坝案例、可变形固体梁振动、可变形弹性固体溃坝及可变形固体障碍物受溃坝冲击等案例对所建框架进行了充分验证。数值结果随后与现有文献发现进行对比。通过对含初始缺口的可变形固体障碍物受水冲击的模拟，展示了该框架准确描述材料损伤与断裂的能力。