A series of experiments subjected to uniaxial and non-proportionally multiaxial cyclic loadings were performed to investigate the ratcheting responses of SA508 Gr.3 steel at room and elevated temperatures. The influences of different stress levels and nonproportional loading paths on the damage-coupled ratcheting responses were discussed. From experimental results, cyclic softening characteristic and dynamic strain aging can be observed under cyclic loadings. Moreover, the steel exhibits an obvious nonproportional path-dependence of the damage evolution under multiaxial loading paths. To numerically simulate the ratcheting responses under uniaxial and multiaxial loadings with the extended cyclic plastic model, the damage-coupled variable was introduced into the classic isotropic and nonlinear kinematic hardening rules. Corresponding material parameters could be calibrated from experimental data, and comparisons between experimental and simulated results were performed to validate the proposed model.

中文翻译：

---

SA508 Gr.3 钢在室温和高温下的损伤耦合棘轮行为：实验和模拟

进行了一系列承受单轴和非比例多轴循环载荷的实验，以研究 SA508 Gr.3 钢在室温和高温下的棘轮响应。讨论了不同应力水平和非比例加载路径对损伤耦合棘轮响应的影响。从实验结果可以观察到循环载荷下的循环软化特性和动态应变时效。此外，钢在多轴加载路径下表现出明显的非比例路径依赖性损伤演变。为了使用扩展循环塑性模型对单轴和多轴载荷下的棘轮响应进行数值模拟，将损伤耦合变量引入经典的各向同性和非线性运动硬化规则。