大震下考虑黏滞阻尼器极限状态的减震结构抗震性能分析

Antiseismic performance analysis of damping structure considering limit state of viscous damper under large earthquake

现有用于黏滞阻尼器模拟的模型只能反映其正常工作状态,因此大震或特大震下,如黏滞阻尼器达到其极限状态则不能使用。针对这一问题,使用C++语言对黏滞阻尼器的Maxwell模型进行二次开发得到了可考虑位移极限状态的阻尼器Maxwell01模型、可考虑力极限状态的阻尼器Maxwell02模型,其中Maxwell02模型既可表示活塞咬边受拉极限状态又可表示驱动支撑受压极限状态,然后将Maxwell01,Maxwell02模型集成到OpenSees中。选择一个6层钢框架结构,分别按无阻尼器、安装黏滞阻尼器但未考虑极限状态、安装黏滞阻尼器且考虑活塞咬边受拉极限状态、安装黏滞阻尼器且考虑驱动支撑受压极限状态4种工况进行罕遇地震水准下的弹塑性时程分析。分析结果对比表明,考虑力极限状态,黏滞阻尼器的耗能能力会下降,因此大震下若不考虑极限状态,会高估黏滞阻尼器减震性能。

The existed models to simulate viscous damper only can represent its normal working condition so that they are not useable if the viscous damper reaches its limit state under large or extremely large earthquakes.To solve this problem,the Maxwell model for viscous damper was developed by C++to obtain the modified Maxwell01 model to account for the displacement limit state of viscous damper and the modified Maxwell02 model to account for the force limit states of viscous damper.The Maxwell02 model can be used to represent the tension limit state of the piston bite and the compression limit state of the drive support.Then the Maxwell01 and Maxwell02 model was integrated into OpenSees.Furthermore,a 6-story steel frame structure was chosen as case study.Four cases of the structure without damper,with viscous dampers without considering the limit state of damper,with viscous dampers considering the tension limit state of the piston bite,and with viscous dampers considering the compression limit state of the driver supports,were analyzed under rarely-occurred level earthquake,respectively.The comparison of the analytical results shows that after accounting for the limit states of viscous dampers,the energy-dissipation capacity of viscous dampers will decrease.Thus if the limit states are not considered under the large earthquake,damping performance of viscous damper will be overestimated.