Abstract The repair and seismic strengthening of a mid-1990s building structure in Christchurch, New Zealand, using fluid viscous dampers and buckling-restrained braces provides a case-study for mixed-system retrofit to improve the seismic performance of ductile reinforced concrete moment frames. The building was designed and detailed to essentially current standards but was very flexible and utilised a precast hollow-core floor system with thin topping slab which is vulnerable to deformations associated with moment frames, as demonstrated in recent New Zealand earthquakes. This paper highlights a simple displacement-based approach to setting retrofit design targets and performance verification. The retrofit using viscous dampers provided an efficient means to reduce ground motion-induced deformations and accelerations. The structural benefits to the rest of the project included no need for foundation strengthening and floor diaphragm strengthening being limited to only the perimeter hollow-core units. Development of the final design and viscous damper specification involved close coordination with the manufacturer to optimise the damper design, fabrication tolerances and site installation methods.

中文翻译：

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新西兰使用双补充阻尼对钢筋混凝土力矩框​​架进行改造

摘要 新西兰基督城 1990 年代中期建筑结构的修复和抗震加固，使用流体粘性阻尼器和屈曲约束支撑，为混合系统改造提供了一个案例研究，以提高韧性钢筋混凝土力矩框​​架的抗震性能。该建筑的设计和细节基本上符合现行标准，但非常灵活，并采用了带有薄顶板的预制空心楼板系统，顶板很容易受到与力矩框架相关的变形的影响，正如最近的新西兰地震所证明的那样。本文重点介绍了一种简单的基于位移的方法来设置改造设计目标和性能验证。使用粘性阻尼器的改造提供了一种有效的方法来减少地面运动引起的变形和加速度。该项目其余部分的结构优势包括不需要基础加固和地板隔板加固，仅限于周边空心单元。最终设计和粘性阻尼器规格的开发涉及与制造商的密切协调，以优化阻尼器设计、制造公差和现场安装方法。