考虑阻尼器极限状态消能减震结构的抗震性能及设计方法研究

Due to the utilization of high-strength concrete and high-strength steel in structural construction, the building is becoming taller and more flexible than ever. In order to control or suppress the structural vibration induced by the earthquakes or winds, the application of passive energy dissipation technologies became widespread. However, the Japan 2011 Tohoku Earthquake destroyed the viscous dampers of a passively-controlled steel building, which is located in Sendai. This event demonstrates that significant improvements need to be made regarding to the study on the seismic performance of passive energy dissipation structures. This project is planning to test the limit states and damage process of dampers by designing physical experiments, and establishes the mathematic model of the restoring force which is able to represent the limit states and failure modes of dampers. The failure path and successive failure modes of passively-controlled buildings under extremely intense earthquakes are investigated by numerical simulation integrating the restoring force model and nonlinear damage model of structural members. Based on the uncertainty analysis method, the relation between the seismic performance level of passive energy dissipation building and the seismic performance index is evaluated quantitatively, and the multi-level seismic performance target is determined. After quantifying the performance level of dampers based on the experimental measurement, dampers' performance targets are set according to the performance requirement of the main building. In this project, the framework of performance-based design methodology of passively-controlled buildings considering the limit states of dampers is initially proposed. This achievement will benefit the theory and application of damage control of passively-controlled buildings.

因高强混凝土和高强钢筋的采用，结构向更高、更柔的方向发展，为控制地震或风振引起的结构振动，消能减震技术的应用日趋广泛。但是其抗震性能的研究尚不够充分，日本3.11震后调查发现一栋消能减震钢结构的粘滞阻尼器发生了严重的损伤和破坏，这表明阻尼器极限状态的存在而且会影响到结构的抗震性能。本项目采用物理试验的方法测试、明确消能器的极限状态和破坏机理，建立考虑阻尼器极限状态的恢复力模型，通过数值模拟研究极端地震荷载作用下消能减震结构的动力失效路径和连续失效模式；基于不确定性分析方法研究消能减震结构的抗震性能水准与抗震性能指标之间的定量关系，建立基于概率的多级抗震性能目标；量化阻尼器的性能水准，建立与主体结构抗震性能目标相匹配的消能器性能目标；初步建立考虑阻尼器极限状态的消能减震结构的性能设计方法，为有效控制消能减震结构的地震损伤和经济损失提供基础理论和研究方法。

针对某消能减震结构的油阻尼器受到311地震的破坏，对造成油阻尼器破坏的原因进行了重演，识别了阻尼器的极限状态，还原了结构损伤的过程；进而发展控制结构损伤的基于性能的抗震分析方法，提出了修复该消能减震钢结构方案，通过实际地震响应数据表明修复后结构的抗震能力得到提高。引入基于空穴增长且适用于钢材延性损伤的微观机制损伤模型，对拟静力试验进行了损伤模拟，明确了阻尼器的损伤程度及损伤演化规律，建立了软钢阻尼器损伤程度与破坏现象对应关系，进而建立了损伤指数与损伤程度的对应关系。提出两类具有可恢复性的消能减震装置，一种新型自平衡式电涡流惯容系统，第二类为拉索式旋转电涡流阻尼器，分别采用了数值模拟和试验的方法进行了研究，验证了这两类阻尼器都具有良好的耗能能力，具有很好的工程应用价值。利用射频识别技术（RFID）设计了带芯片的贴片天线传感器以实现无源无线的结构应变监测，天线实测谐振频率与应变具有较好的线性关系，拟合直线所得实测灵敏度与通过公式所得计算灵敏度相符较好，精度可达十万分之一个应变，量程为1%应变。