Experimental Technology and Management

为研究建筑中设备与建筑结构的相互作用，该文基于设备-Benchmark钢框架缩尺模型开展了振动台试验。文章以水冷机原型为例，采用解耦重构方法将设备系统分为质量特征部分和刚度特征部分，分析了不同质量和刚度下设备的频率，以及设备频率对耦合体系振型和动力响应的影响。试验结果表明随着设备频率的降低，建筑结构的一阶振型由平动向静止转变，而设备由静止向平动转变。耦合效应使得建筑结构的响应曲线更加尖锐，提升了振动剧烈持续时的加速度峰值，降低了位移峰值，而设备的加速度响应呈现出了相反的演变规律。该研究成果可为设备-结构耦合体系的抗震设计提供理论支撑。

[Objective] This study investigates the interaction between equipment and building structures, with a focus on how equipment mass and stiffness influence the dynamic response of these structures. To achieve this, large-scale shaking table tests were conducted using a scaled model of a benchmark steel frame of the equipment. [Methods] The equipment model was based on a water-cooling machine, a crucial component of large-scale equipment used in industries relating to the medical, chemical, and high-tech sectors. The selection of the model considers the overall weight, vibration characteristics, and other features of this type of equipment. The decoupling reconstruction method was used to decompose the equipment system into mass and stiffness characteristic components. The scaled model of the main structure used a benchmark steel frame, which is a standard model for structural analysis and validation research. The El Centro seismic wave was applied as an input to the shaking table at a maximum peak acceleration of 0.4 g, complemented by a white noise input of 0.05 g before and after each test. For the coupled system, connectors with varying stiffness were sequentially swapped under each counterweight level, resulting in five tests and 25 working conditions. Through these large-scale shaking table tests, the frequencies of the equipment at different masses and stiffnesses were analyzed, along with the effects of equipment frequencies on the vibration modes and dynamic responses of the coupled system. The acceleration time-history curves were directly recorded using acceleration sensors, while displacement time-history curves were derived through integration methods. [Results] As the frequency of the equipment decreased, the first mode shape of the main structure transitioned from translational motion to stationary, while the third mode shape shifted from torsional to translational. The first and second mode shapes of the equipment evolved from relatively stationary to translational. High-frequency equipment can be regarded as an additional mass for the seismic performance analysis of coupled systems. The coupling effect sharpened the acceleration time-history curve of the main structure, increasing the peak during intense vibration periods and decreasing the peak during mild vibration periods, while the acceleration time-history curve of the equipment exhibited an opposite evolutionary pattern. As the frequency of the equipment decreased, the maximum acceleration peak of the structure first decreased and then increased, whereas the equipment displayed a trend of first increasing and then decreasing. The equipment tended to suppress the acceleration response of the structure. The coupling effect also sharpened the displacement time-history curve of the main structure, resulting in a reduction in the displacement amplitude, while the displacement amplitude of the equipment demonstrated similar characteristics. As the frequency of the equipment decreased, the maximum peak displacement of the structure first decreased and then increased, while the equipment showed a trend of first increasing and then decreasing, indicating that the equipment can suppress the displacement response of the structure. [Conclusions] In seismic design, it is essential to analyze equipment and structure as integrated systems to accurately assess their actual responses under seismic action, thereby avoiding unnecessary increases in cost due to overestimating seismic demand. Additionally, placing equipment sensitive to acceleration responses, which may induce adverse resonance, should be avoided in areas identified as seismically weak. This research provides theoretical support for the seismic design of coupled equipment-structure systems.