【作者】 蓝文武；

【导师】 韦树英；

【作者基本信息】 广西大学 ， 结构工程， 2005， 博士

【摘要】 本文在充分分析国内外相关研究成果的基础上,对巨型钢框架悬挂结构体系进行了主动变刚度和主动变阻尼的半主动振动控制研究,具体包括以下几个方面: 1.第1章,综述了巨型结构悬挂体系及其半主动振动控制的发展、研究现状及工程应用,介绍本文选题的出发点以及论文的主要研究内容。 2.第2章,采用随机分析方法对巨型钢框架悬挂结构单、多自由度体系进行了主子结构间频率比、质量比、阻尼比等参数的优化分析研究,建立起这些参数与结构随机响应均方差之间的相关关系,从关系规律中确定最优参数。并进一步提出了直接以吊杆长度作为参数,通过建立该参数与结构的均方差响应的关系曲线,从中确定最优杆长的吊杆长度实用设计方法。 3.第3章,提出一种可实时、连续改变悬挂层吊杆长度的主动变刚度控制装置,该装置通过实时改变吊杆的长度而改变结构体系的水平振动的动力特性,同时对结构体系产生了水平向弹性恢复力增量,合理设计后,该弹性恢复力增量成为了有利于结构减震、类似于结构控制中的控制力。 4.基于LQR最优控制理论,本文在吊杆长度改变引起的弹性恢复力增量(即主动变刚度控制力)与二次型最优控制力之间建立了对应关系,并在使弹性恢复力增量尽量逼近或跟踪实现LQR最优主动控力的原则下,推导得到了求解最优弹性恢复力增量的算法,并据此建立了求解实时最佳吊杆长度改变量的方法。算例分析表明,该主动变刚度装置对结构的位移和速度反应的控制效果较好,但对结构的加速度反应的控制效果不理想。 5.在第4章,将已有的一种典型的主动变阻尼控制装置引入巨型钢框架悬挂结构体系的振动控制中,并以一种不同于已有研究的装置布置位置方式进行更多还原

【Abstract】 On the basis of a thorough analysis of the related research findings home and abroad, this thesis aims at a research of the vibration control of active variable stiffness and active variable damper on steel mega-frame with suspended systems. It comprises the following sections:1). In chapter 1, the development,actuality and application in engineering of huge structure with suspended substructure and semiactive control technology are introduced,and the present research overview and development trend are sketched ,finally,the background and main research contents of this thesis are introduced.In chapter 1, firstly,the reliability of equivalent model is identified by summing up the existing equivalent simplified models to steel mega-frame and by analyzing the seismic response concerning the precise model and equivalent model based on examples separately.2). In chapter 2,the relationship of the parameters such as frequency ratio, mass ratio, damper ratio of megaframe and substructure, and mean-square of random response is given .These parameters is optimized by random analysis method for single-degree and multi-degrees of freedom of steel mega-frame structure with suspended systems. And the practical analysis method for the length of suspension boom is obtained by establishing the relationship between the parameter-length of suspension booms and the mean-square response with the variety of the parameters directly.3). In chapter 3, an active variable stiffness systems, which can provide a live and continuous change of the length of suspension booms of suspension floor, is adopted. The systems is used to change the length of suspension booms so as to change the dynamic characteristic of structure. At the same time, the variety of the length of suspension booms is to bring up elastic restoration force that can work as the control force for semi-active control devices as long as it is designed reasonably. 4). Based on the LQR optimum control theory, this thesis establishes elasticrestoring force that is caused by changing the length of suspender, that is , the relationship between the active variable stiffness control force and quadratic optimal control force, and under the principle of keeping elastic restoring force closest to or follow and realize LQR optimum active control force, the algorithm of solving optimum elastic restoring force can be deduced and obtained , and hereby a method which can solve the real-time optimum variation of suspender length is established. As the example analysis indicates, this active variable stiffness system has better controlling effects on the structural displacement and velocity reaction, but the effects on the supressing acceleration of structure are unsatisfactory.5). In chapter 4, an existing typical active variable damping control system is introduced into the giant steel frame with suspended systems, and the controller is set in a new way that is different from the already researched one, in which an active variable damper is set between the main structure floors alone, and between the sub structure floor alone.6). A concise performance index expression is put forward, and by using the control theory of the SMC(sliding mode control), the switch function and variable structure controller is analyzed and designed, resulting in an algorithmic method of variable structure whose expressing form is relatively concise. As example analysis indicates , the control way of active variable damping has a better control result to the displacement and velocity reaction of the structure, and a certain control result to the acceleration reaction of the structure. So active variable damping control is a vibration control system which has better robustness.7). In chapter 5 , conclusions have been made, and problems remaining to study further are put forward.更多还原