考虑网壳结构失效特征的修正Park-Ang地震损伤评估研究

Seismic damage assessment of reticulated shell structures using a modified Park-Ang model with consideration of failure characteristics

摘要:

为研究三维地震作用下网壳结构损伤程度,基于增量动力分析（IDA）方法对网壳结构两种典型失效特征进行分析并加以讨论。通过修正Park-Ang地震损伤模型公式相关参数项,考虑结构变形和能量两个动力响应指标的影响,建立网壳结构损伤判别准则,提出网壳结构不同失效状态对应的损伤性能水准。结果表明:网壳结构的失效破坏特征分为动力强度失效和动力失稳失效,修正的Park-Ang地震损伤模型可较好地评估这两种失效模式的损伤程度,网壳结构失效时的损伤值收敛于1.00且离散性较小。网壳结构的破坏程度可以划分为基本完好、轻微破坏、中等破坏、严重破坏和倒塌,对应的损伤界限值分别为0、0.15、0.65、1.00。根据规范要求，选取四条不同类型地震波加以验证,证明修正的Park-Ang地震损伤模型能够较好地考虑位移与耗能的耦合效应,对网壳结构整体损伤评估更为合理。

Abstract:

To evaluate the damage degree of reticulated shell structures under 3D seismic action, two typical failure characteristics of these structures were analyzed using the incremental dynamic analysis method. By modifying relevant parameters in the formula of the Park-Ang seismic damage model, a damage assessment criterion was developed, incorporating two dynamic response indexes: structural deformation and energy. Moreover, damage performance levels corresponding to various failure states of reticulated shell structures were proposed. Results indicate that the failures of reticulated shell structures can be classified into dynamic strength failure and dynamic instability failure. The modified Park-Ang seismic damage model effectively evaluates the damage degree for these failure modes, with the damage value converging to 1.00 and exhibiting minimal dispersion. The damage degree of reticulated shell structures can be categorized into five levels: basically intact, slight damage, moderate damage, severe damage, and collapse, with corresponding damage limits of 0, 0.15, 0.65, and 1.00, respectively. Finally, by verifying the model with four different types of seismic waves that satisfy the specification, the modified Park-Ang seismic damage model effectively accounts for the coupling effect of displacement and energy consumption, providing a more accurate assessment of the overall damage to reticulated shell structures.