基于多自由度结构的DTMD参数分析及设计方法

双调谐质量阻尼器参数较多,其设计方法、有效性的研究仍不完善,鉴于此,针对地面运动作用下多自由度结构双调谐质量阻尼器的优化设计方法进行了初步研究,推导了双调谐质量阻尼器的位移动力放大系数(DDMF)。基于最优化目标函数研究了优化设计参数对振型参与系数的敏感性;在此基础上,给出了一种双调谐质量阻尼器的优化设计方法,并通过某高层钢结构的仿真分析对该优化设计方法的有效性进行了评价,结果表明,优化设计后的双调谐质量阻尼器可有效降低受控结构的位移动力响应。     

脱层材料与槽接式挫屈束制支撑的性能研究

挫屈束制支撑耐震性能优劣与否与脱层材料性能有密切关系,首先提出了一种估算脱层不完全因子的方法,利用4组分别使用不同脱层材料的挫屈束制支撑进行构件试验;研究结果表明以黏性橡胶作为脱层材料具有可靠性、经济性与优良的施工性。特别介绍了地震工程研究中心近期所研发的槽接式挫屈束制支撑,并通过3组实尺寸构件试验验证了其耐震性能;测试构件包含一组长度为12.5m,最大抗压强度超过16800kN,核心消能段应变量达3.5%的构件。试验结果表明,新研发的槽接式挫屈束制支撑经济效益极高,迟滞消能行为良好稳定,具有优良的耐震性能,各组试体于试验停止前所累积的总非线性变形量皆超过400倍斜撑屈曲位移量;研究亦显示,非线性结构分析软件PISA3D可准确预测其受力与变形反应。     

Active tuned mass damper for damping of offshore wind turbine vibrations

An active tuned mass damper (ATMD) is employed for damping of tower vibrations of fixed offshore wind turbines, where the additional actuator force is controlled using feedback from the tower displacement and the relative velocity of the damper mass. An optimum tuning procedure equivalent to the tuning procedure of the passive tuned mass damper combined with a simple procedure for minimizing the control force is employed for determination of optimum damper parameters and feedback gain values. By time domain simulations conducted in an aeroelastic code, it is demonstrated that the ATMD can be used to further reduce the structural response of the wind turbine compared with the passive tuned mass damper and this without an increase in damper mass. A limiting factor of the design of the ATMD is the displacement of the damper mass, which for the ATMD, increases to compensate for the reduction in mass. Copyright © 2016 John Wiley & Sons, Ltd.     

Hybrid damper with stroke amplification for damping of offshore wind turbines

The magnitude of tower vibrations of offshore wind turbines is a key design driver for the feasibility of the monopile support structure. A novel control concept for the damping of these tower vibrations is proposed, where viscous‐type hybrid dampers are installed at the bottom of the wind turbine tower. The proposed hybrid damper consists of a passive viscous dashpot placed in series with a load cell and an active actuator. By integrated force feedback control of the actuator motion, the associated displacement amplitude over the viscous damper can be increased compared with the passive viscous case, hereby significantly increasing the feasibility of viscous dampers acting at the bottom of the wind turbine tower. To avoid drift in the actuator displacement, a filtered time integration of the measured force signal is introduced. Numerical examples demonstrate that the filtered time integration control leads to performance similar to that of passive viscous damping and substantial amplification of the damper deformation without actuator drift. Copyright © 2016 John Wiley & Sons, Ltd.     

设置FPS质量调谐阻尼器减振效果分析研究

根据拉格朗日方程推导了结构设置FPS调谐质量系统地震动力反应分析计算公式,并考虑了接触面滞滑效应的影响。分析与计算结果表明:设置质量调谐系统之后,结构动力反应层间位移有所减小。当接触面滑动摩擦系数为0.15左右、滑道半径为0.7 m、调谐附加质量为楼层质量的1.4倍以上时,质量调谐系统具有较好的减振效果、消能效果与复位能力。     

An inductance-based technique for the measurement of magnetic moment of the magnetorheological fluids

We presented a detailed study of the inductance properties of a MRF-based system with different MRF volume fractions under a magnetic field. The inductance of the system raised firstly and then decreased while the magnetic field kept increasing. We theoretically analyzed the mechanism of the field-induced variation of the inductance and deduced that the magnetic field dependence of the inductance could be represented by the derivative of the magnetic moment of MRF, thus the M–H curves of the MRF could be derived from the inductance measurement proceeded in our work. This method for the magnetization calibration was very convenient and economic for manipulation compared with the traditional magnetization meter techniques and has been proved to be feasible according to the experimental results which showed a satisfactory measurement precision.     

磁流变阻尼器性能试验研究

基于磁流变阻尼器的性能试验，对磁流变阻尼器的阻尼力性能进行了研究，得出力一位移的滞回曲线和力一速度曲线，并分析了影响阻尼力的各种因素，从而总结出磁流变阻尼器的阻尼力性能。     

降低架空输电线路防振锤滑移率的研究

在架空输电线路的导、地线上安装防振锤,是防止架空输电线路导、地线因为振动而出现断线、断股事故的主要措施之一。但由于各种原因的作用,防振锤在安装一段时间后滑移出原有的安装位置,失去防振作用,威胁导、地线安全运行。分析了防振锤出现滑移的各种原因,并对现使用的防振锤结构提出改进措施,取得了较好的效果。     

某型液压阻尼器启动力差异分析及改进

为解决某型机载液压阻尼器前推与后拉启动力差异较大的问题,对密封结构及阻尼腔排气结构进行改进设计。分析故障机理并确定原因是由密封设置不合理造成的启动力异常以及内部油液未充满造成的伸出方向阻尼性能下降,共同导致了侧杆装置前推后拉启动力差异。验证结果表明：该设计能提高阻尼器的密封性能,满足系统启动力的要求。     

基于矩形凸块的盘式磁流变制动器设计与仿真

基于磁流变液的流变特性,设计了一款盘面加工有矩形凸块的盘式磁流变制动器,推导了其制动力矩计算公式,基于Matlab/simulink建立了仿真模型,不断优化矩形凸块的尺寸参数。仿真结果表明,当加工有12个宽度为2 mm、深度为1.5 mm的矩形凸块时,产生的制动力矩达到626 N·m,比未加工凸块时的制动力矩提高了31.5%,表明设计的磁流变制动器可以有效地提高制动力矩。