考虑黏滞阻尼器极限状态的结构抗震性能评价及加固

Damage and failure of dampers under extreme conditions might have unexpected adverse effect on seismic performance of the structure. In response to this problem, this research is carried out by focusing on following key scientific problems: ultimate failure mode and failure mechanism of viscous dampers (including adjacent components such as gusset plates), critical factors and mechanism of ultimate performance of viscous dampers to influence seismic performance of the structure, damper protection and structural seismic performance improving mechanism of the additional flexible component. By establishing analytical model considering the ultimate state of viscous dampers, the damage and failure mode, as well as the ultimate performance are clarified. Then the corresponding numerical simulation method is built. Based on the simulation method, influence of viscous dampers in ultimate state upon structural seismic performance is investigated. Based on which evaluation and design method considering the ultimate state of dampers are established. Reasons of damage and failure occurred in viscous dampers of the seismic damaged building can also be revealed. Based on this, the flexible retrofitting concept of viscous dampers is proposed. The protection mechanism of the additional flexible component and its influence on structural seismic performance are investigated, to establish the design method for the flexible retrofitting, and to apply the retrofitting on the seismic damaged building. Finally the innovative products of this research includes: systematical clarification of mechanism and law regarding to ultimate state of viscous dampers, as well as the corresponding analytical, design and retrofitting method.

阻尼器在极端条件下实际发生的损伤破坏现象将对结构的抗震性能产生预想外的不利影响。针对这一问题，本项目拟围绕极限状态下黏滞阻尼器（包括节点板等附属部件）的破坏模式及破坏机理，黏滞阻尼器极限性能影响结构抗震性能的关键因素及作用机理，附加的耗能柔性部件对阻尼器的保护机制及对结构抗震性能的改善机理等科学问题展开研究。提出考虑黏滞阻尼器极限状态的分析模型，揭示其损伤破坏模式，明确其极限性能，建立相应的数值模拟方法；基于该方法，揭示极限状态下黏滞阻尼器影响结构抗震性能的机理、规律，建立相应的结构抗震性能评价与设计方法，揭示实际震损结构中黏滞阻尼器损伤破坏的原因；在此基础上，提出黏滞阻尼器的柔性加固理论，揭示耗能柔性部件的保护机制及其对结构抗震性能的影响，建立黏滞阻尼器的柔性加固设计方法并应用于实际震损结构。最终的创新成果包括系统揭示黏滞阻尼器极限状态的机理规律，并给出相应的分析方法，设计方法和加固方案。

黏滞阻尼器在极端条件因超越性能极限而实际发生的损伤破坏现象将对结构的抗震性能产生预想外的不利影响。针对这一问题，本项目围绕极限状态下黏滞阻尼器的破坏模式和机理，附加柔性耗能部件对黏滞阻尼器的保护机制，附加柔性耗能部件情况下黏滞阻尼器对结构抗震性能的提升机理等关键科学问题展开研究。本项目以附加惯容元件作为提升黏滞阻尼器响应控制效果和抑制黏滞阻尼器超越极限状态风险的手段，考虑隔震层响应控制，薄弱层结构响应控制，连体结构响应控制等对黏滞阻尼器具有较高变形耗能需求的情况，建立了结构附加黏滞阻尼器及惯容元件情况下的理论模型，对结构响应控制水平和黏滞阻尼器控制效率进行了参数分析，确定了黏滞阻尼器、惯容元件等所构成的减震系统的关键参数，揭示了并联及串联惯容元件情况下黏滞阻尼器对结构响应的高效控制机理；在此基础上，定义了结构不同响应的减震率，惯容减震系统的附加等效阻尼比及其增效系数等指标，建立了以结构响应降低效果和附加等效阻尼比为目标的惯容减震系统优化理论，分析了关键参数的最优取值，最佳控制效果和控制效率的影响因素和变化规律；针对连体结构，薄弱层结构等具体工程问题，在惯容减震系统优化理论的指导下，分别提出了面向黏滞阻尼器控制效果提升和控制效率提升的优化设计方法，从频域分析和时域分析等多种角度，对两种优化设计方法，以及基于定点理论的传统设计方法进行了对比分析，验证了研究结论的可靠性和设计方法的有效性。项目获得的主要结论包括：通过附加惯容元件能够有效提升黏滞阻尼器对结构响应的控制效果和控制效率，在极端情况下抑制黏滞阻尼器超越极限状态的风险；黏滞阻尼器的阻尼比，附加惯容元件的质量比和惯容减震系统的刚度比是决定响应控制效果及控制效率的关键参数；采用本项目所提出的优化思想和设计方法，能够正确获得上述关键参数的最优设计值，最大限度地实现提升结构响应控制效果和保护黏滞阻尼器的双重目的。