Seismic-induced damage, integral to the safety evaluations of major engineering projects, persists as a key focus of research worldwide. Based on the Scaled Boundary Finite Element Method (SBFEM) and the Phase-Field Method (PFM), a coupled algorithm tailored for reciprocal loading was introduced in this paper, integrating strategies including "closure constraints," "numerical threshold strategy," and "subdomain block integration." Adopting object-oriented principles, a universal coupling solution framework has been built and seamlessly embedded within GEODYNA, a self-developed finite element software system. The accuracy was validated through rigorous benchmark tests. The entire process of crack initiation, propagation, and dynamic opening-closing cycles in the Koyna concrete gravity dam was reproduced. Furthermore, the effect of mesh size and computational timestep on the structural seismic response, crack localization, and the extent of damage in the dam were explored. The outcomes demonstrated that the SBFEM-PFM coupling algorithm performs effectively and meets the engineering precision criteria for seismic evaluations and reinforcement analyses of crucial structures.

中文翻译：

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用于地震载荷的缩放边界有限元和相场耦合算法


地震引起的损害是重大工程项目安全评估不可或缺的一部分，一直是全球研究的重点。该文基于缩放边界有限元法 （SBFEM） 和相场法 （PFM），引入了一种针对倒易加载的耦合算法，集成了“闭合约束”、“数值阈值策略”和“子域块集成”等策略。采用面向对象原则，构建了一个通用耦合解决方案框架，并无缝嵌入到自主开发的有限元软件系统 GEODYNA 中。准确性通过严格的基准测试得到验证。再现了 Koyna 混凝土重力坝中裂缝萌生、扩展和动态开合循环的整个过程。此外，还探讨了网格尺寸和计算时间步长对结构地震响应、裂缝定位和大坝破坏程度的影响。结果表明，SBFEM-PFM 耦合算法有效执行，并满足关键结构的地震评估和加固分析的工程精度标准。