Study on Development of High Performance Seicmic Damper for Reducing Excess Response Amplitude

（1）工业设备管道系统的动态特性是经济和安全设计中必须考虑的重要问题之一。管道系统通常通过诸如导轨、弹簧吊架、液压或机械缓冲器和某些能量吸收器等装置在多个点处连接到支撑结构。当摩擦阻尼器受到重视时，由于滑动运动的最大位移受到设备间隙的限制，接触面处的能量耗散量受到限制。为了提高磁摩擦阻尼器的耗能量，提出了滚珠丝杠型磁摩擦阻尼器。该阻尼器通过滚珠丝杠将单向运动转化为旋转运动，从而提高了耗能能力。在这项工作中，建议的阻尼器的基本特性进行了澄清。根据试验得到的参数建立了数值模型，并将模拟结果与试验结果进行了比较。(2)本文提出一种利用磁流变液的可调阻尼装置。通过对阻尼器施加不同的动态载荷，对有无磁场作用下的阻尼特性进行了实验研究。试验中测得的最大阻尼力和可控能力分别接近300 kN和180 kN，可用于大型结构的半主动振动控制。此外，它被证实，在模拟中使用的简单的分析模型是有助于预测MR阻尼力。

Research results of this project is summarized as follows :(1) The dynamic characteristics of piping system installed in industrial facilities have to be recognized as one of the significant issues in economic and safety design consideration. Piping systems are generally connected to supporting structures at several points by means of devices such as guides, spring hangers, hydraulic or mechanical snubbers and certain energy absorbers. When friction damper attracts attention, the amount of energy dissipation at contact surface is restricted, because the maximum displacement of sliding motion is limited by the clearance of the equipment. In order to increase the amount of energy dissipation, the ball screw type magnetic friction damper is proposed. This damper is expected to increase the energy dissipation by converting one directional motion to rotating motion by ball screw. In this work, the fundamental characteristics of proposed damper are clarified. The numerical model is made considering parameters obtained from testing, and the results from simulation are compared with the results from testing.(2) A capacity adjustable high damping device using an MR sluid was newly developed in this study. The damping characteristics with and without the magnetic fields were experimentally investigated by applying the several dynamic loading to the damper. The maximum damping force and the controllable capacity measured in the tests are almost 300 kN and 180 kN, which enables practical applications on semi-active vibration control of large-scale structures. Furthermore, it was confirmed that the simple analytical model used in the simulation is helpful for predicting MR damping forces.