基于监测数据的结构地震损伤追踪与量化评估方法

TRACKING AND QUANTITATIVE EVALUATION OF EARTHQUAKE-INDUCED STRUCTURAL DAMAGE USING HEALTH MONITORING DATA

基于延性的工程抗震设计允许结构在强地震作用下进入非线性,即允许结构产生地震损伤。从物理和力学的角度,抗震行为模拟与性态评估一般考虑地震损伤的峰值效应和累积效应。但是,由于先验性知识(如滞回耗能、承载力与变形能力)的限制,抗震研究中广泛应用的Park-Ang损伤模型较难直接用于大型在役结构的地震损伤评价。受到控制领域模型参考思想的启发,该文提出一类基于数据驱动的损伤评估模型,能自适应于不同的受力状态与破坏模式,实现综合评估震损结构峰值和累积损伤效应。利用美国NEES计划公开的足尺钢筋混凝土(RC)柱动力试验数据,研究了所提出数据驱动损伤指标与RC柱地震损伤发展的相关性与时域追踪效果,验证了评估指标能有效区分RC柱水平侧移与弯曲变形相应损伤的发展与累积差异。此类基于模型参考思想的新型损伤评估指标,不需要提前获知结构非线性特征和计算滞回耗能,可应用于基于强震观测的工程结构抗震性态评估。

Structural nonlinear behavior is allowed during strong earthquakes according to the ductility-based structural design,which relates to the earthquake-induced structural damages.From the viewpoint of physics and mechanics,the peak effect and cumulative effect of seismic damage are comprehensively considered in numerical modeling and performance assessment of structural behaviors.However,the application of classical Park-Ang damage model for large-scale existing structures,which is mostly used in seismic studies,may be relatively limited due to the lack of prior knowledge(such as the hysteretic energy dissipation,the yielding force and the ultimate displacement capacity).Inspired by the model reference concept in the field of control study,a datadriven damage evaluation model is proposed in this paper to quantify both the peak and cumulative damage effects,which may be used for different deformation modes.A full-scale reinforced concrete(RC)column subjected to shake table test from the NEES Database is utilized to investigate the correlation between the development of damage and the proposed damage model and the tracking performance in the time-domain.The new damage evaluation index is proved to be able to distinguish the difference in damage development between the shear and flexural deformation of RC column.Generally,the proposed damage index,adopting the model reference concept,may not require structural hysteresis characteristics and the calculation of dissipated energy,and can be applied to practical seismic evaluation.