I - Single Floor Moment Resisting Frame Real-time Hybrid Simulation

A single floor steel MRF specimen is tested that represents the stiffness of the reference SDOF structure. Seismic mass and damping are assumed numerically that can be varied to achieve any desired natural frequency (fn) for the reference SDOF system. A schematic view of this worst-case RTHS setup is shown in the experiment photo section. In practice, 1% of identified MRF stiffness (8.6 kip/in) is added into the numerical substructure to avoid the singular RTHS configuration. Several outer-loop actuator motion controller are tested in Trial 1, including the proposed H∞ controller. The linear SDOF reference structural response data are included to assess the experimental error. The servo-hydraulic controller proportional (Kp) gain is changed from the nominal setting of 3.0 to both 2.5 and 3.5. Then the tests at fn=6Hz are repeated without identification or redesign (i.e. the original controller is applied). The various outer-loop control strategies are tested in Trail 2 on the new systems for robustness evaluation. RTHS data demonstrate the superior performance of the proposed H∞ controller, in both test stability/accuracy and robustness.

测试了一个单层钢抗弯框架（MRF）试件，其刚度与参考单自由度（SDOF）结构的刚度一致。通过数值方法设定地震质量和阻尼，可通过调整这些参数使参考SDOF系统达到任意所需的固有频率（fn）。该最坏工况下的实时混合仿真（RTHS）装置示意图见实验照片部分。实际操作中，为避免RTHS配置出现奇异性，在数值子结构中额外加入了已识别MRF刚度的1%（8.6 kip/in）。试验1中测试了多种外环作动器运动控制器，包括所提出的H∞控制器。为评估实验误差，数据集包含了线性SDOF参考结构的响应数据。伺服液压控制器的比例增益（Kp）从标称值3.0调整为2.5和3.5。随后，在不进行识别或重新设计（即采用原始控制器）的情况下，重复进行fn=6Hz的测试。试验2中，在新系统上测试了多种外环控制策略以评估其鲁棒性。RTHS数据表明，所提出的H∞控制器在测试稳定性/准确性和鲁棒性方面均表现出优越性能。