悬吊多质量摆体系力学机理及减振性能试验研究

Experimental study on the mechanical mechanism and vibration reduction performance of suspended multi-mass pendulums

传统悬吊质量摆有悬吊单摆、串联式悬吊多摆和并联式悬吊多摆,这几种类型摆构造简单、机理明确,但调谐频带较窄,应用在低频率超高层结构下摆长过长、高频率高层结构下摆长过短,限制其在实际工程中的应用。为此,提出装有弹簧的串、并联式悬吊多摆结构,建立装有串、并联式悬吊多摆的结构体系动力学方程。为研究这两类悬吊摆的减振性能,通过数值模拟对比分析传统悬吊质量摆与装有弹簧的串、并联悬吊摆对受控结构的减振效果,并对受控结构与非受控结构进行一系列振动台试验,验证悬吊单摆、悬吊串、并联式无弹簧双摆、悬吊串、并联式弹簧双摆在传统地震动下以及四类场地地震动作用下对被控结构减振控制的有效性。数值模拟与振动台试验结果均表明,装有弹簧的串联式悬吊多摆减振效果最优,其具有增大调谐频带、实现多阶振型控制、灵活调节摆长的优点,适用于工程实际中。

Traditional suspension mass pendulums include suspension single pendulums,serial suspension multiple pendulums and parallel suspension multiple pendulums.These types of pendulums are simple in structures and clear in mechanism,but narrow in tuning frequency band,excessively long hem of low-frequency super high-rise structures and excessively short hem of high-frequency high-rise structures limit their application in practical engineering.In order to solve this problem,the dynamic equation of the multi-pendulum structures with string and parallel suspensions was established.In order to study the damping performance of these two types of suspension pendulums,the damping effects of the traditional suspension mass pendulum and the string and parallel suspension pendulums with spring on a controlled structure were compared and analyzed by numerical simulation,and a series of shaking table tests were carried out on five types of controlled and uncontrolled structures.The effectiveness of suspension simple pendulum,suspension string,parallel spring-free double pendulum,suspension string,and parallel types of spring double pendulums under traditional ground motion and four kinds of ground motions was verified.The results of numerical simulations and shaking table tests show that the serial suspension multi-pendulum with spring has the best damping effect,and it has the advantages of increasing the tuning frequency band,realizing the multi-order mode control and adjusting the pendulum length flexibly,which is suitable for engineering practice.