【摘要】 在罕遇地震分析中,考虑构件的损伤退化特征对提高杆系模型的计算准确性显得尤为重要,因此,如何利用有限元准确地模拟构件局部屈曲的退化现象是进行参数分析并提取退化模型的重点所在,而钢材的本构关系则是其中的基础.采用通用有限元软件ABAQUS,对比分析不同本构模型的计算结果与典型局部屈曲退化试验结果,提出能够准确计算循环荷载下局部屈曲退化行为的钢材本构模型.在校准模型的基础上,通过参数分析,探讨影响构件局部屈曲损伤退化的因素,提出不同控制因素下损伤退化规律,为提出考虑损伤退化的杆系模型提供有力的工具.分析结果表明:翼缘宽厚比、强屈比以及腹板高厚比会一定程度影响局部屈曲退化现象,其中翼缘宽厚比对其最终退化程度有明显影响,但屈服强度对退化过程影响不大.更多还原

【Abstract】 In severe earthquake analysis,it is necessary to propose damage and degradation characteristics for improving the accuracy of "line" model.Therefore,it is important to accurately simulate local buckling damage and degradation with finite element method for parameter analysis.Appropriate constitutive model is needed.By comparing the results of using different constitutive models in ABAQUS with typical local buckling degradation tests,a steel constitutive model was proposed to accurately calculate the degradation of local buckling.Based on the calibrated model,damage and degradation factors of local buckling were discussed by parameter analysis;cumulative damage rules under different control factors were proposed,which provided a powerful tool for improving the accuracy of "line" model.The results showed that:flange and web width-thickness ratio and steel strength-yield ratio would seriously affect the local buckling damage and degradation.Flange width-thickness ratio had most significant effect on ultimate degradation.However,the yield strength had little effect on degradation process.更多还原