【作者】 孙松建；

【导师】 李忠献；

【作者基本信息】 天津大学 ， 结构工程， 2012， 博士

【摘要】 作为交通枢纽工程，桥梁结构是生命线工程的重要一环，其建设造价高，工程作用重大，一旦发生地震破坏，将会给社会造成巨大的经济损失，且震后修复非常困难。连续梁桥作为一种重要的桥型，以其良好的力学性能和经济性能等优势，在全世界范围内被广泛采用。本文以连续梁桥为研究对象，对其进行了智能控制和数值模拟，系统的研究了连续梁桥结构体系在强震作用下的地震响应及损伤。本文的研究工作主要包括以下几个方面：（1）为了更好的研究连续梁桥结构在强震作用下的半主动控制及其数值模拟，本文首先基于控制装置和控制算法，详细的介绍了磁流变阻尼器的构造、性能、工作模式和出力模型；然后针对控制系统的状态方程、最优控制算法、主动控制力与状态空间之间的增益关系，对比分析了不同控制算法间的异同点，并给出了基于磁流变阻尼器常用的几种半主动控制算法及其物理意义。这为连续梁桥采用半主动控制方法的研究、应用及其数值模拟奠定了理论基础。（2）在连续梁桥的智能控制研究中，大多以控制梁的加速度和控制桥墩墩顶与梁间的相对位移为目的，而忽略了对桥墩损伤的控制。本文提出了一种改进的半主动控制策略，通过在限界Hrovat最优半主动控制算法中引入桥墩的损伤指数，使桥梁的地震反应和桥墩的损伤同时得到控制。本文以一设置了磁流变阻尼器的两跨连续梁桥为研究对象，采用MATLAB对其进行数值模拟分析，对所提出的半主动控制策略进行了多种工况下的验证。计算结果表明，采用考虑损伤的半主动控制策略，能够在较好控制桥梁地震反应的同时，有效减轻桥墩在强震过程中的损伤，使桥墩的损伤指数得到明显降低。（3）本文提出了一种多墩联合半主动控制算法，该控制算法在主动最优控制力的基础上，综合考虑连续梁桥各墩的损伤状态，通过调整阻尼器的目标出力，在主梁加速度和各桥墩墩顶与主梁间的相对位移得到控制的同时，使各桥墩的损伤指数能够平均分配。并以一设置了磁流变阻尼器的三跨连续梁桥为研究对象，采用MATLAB对其进行数值模拟分析，对所提出的半主动控制算法进行了多种工况下的验证。计算结果表明，采用多墩联合半主动控制算法，能够较好地控制桥梁的地震反应，同时使本应破坏最严重的桥墩在强震过程中的损伤指数得到有效的降低，达到各桥墩损伤平均分配的效果。（4）本文提出了一种在大型有限元软件ABAQUS中实现半主动控制的方法。传统控制理论的数值模拟方法大多是基于MATLAB数值程序实现的，一般需要一定的假设和简化，而在强震激励作用下，难以保证结构的地震响应始终处于线弹性状态，这将不可避免地导致结构响应分析存在一定的误差。采用本文所提出的数值模拟方法可以更好的考虑在使用MATLAB进行数值分析时结构的塑性响应。本文利用该方法分析了一个三跨连续梁桥的地震响应，并在有限元软件ABAQUS中成功实现了半主动控制的数值模拟。计算过程和结果表明，本文所提出的方法可实现对带有半主动控制装置的结构进行地震响应的精细化模拟，为结构智能振动控制研究提供一个更加有效的途径。更多还原

【Abstract】 Bridges serve as transportation hubs, and are important parts of the lifelineengineering. They are of high construction cost and significant engineering meaning.The seismic damage of long span bridges causes great economic loses and greatrehabilitation difficulty. As an important bridge type，continuous beam bridge hasbeen widely adopted worldwide due to its mechanical and economic superiorities. Theresearch in this dissertation focuses on the intelligent control, seismic response anddamage of continuous beam bridge, in which the following aspects are included:(1) A full introduction of the structure, performance, operating modes and outputmodel of magnetorheological (MR) damper based on the control device and controlalgorithm is given at first for better research on the semi-active control and numericalsimulation of continuous beam bridge under the strong earthquake. Then, differencesbetween different control algorithms are compared based on the the equation of state,active control force and the gain relationship between them are summarized.Accordingly, several common semi-active control algorithms based themagnetorheological damper and their physical significance is detailedly expounded,which lays a theoretical foundation for the research on the semi-active control methodand numerical simulation of continuous beam bridge.(2) As for the intelligent control of the continuous beam bridge, most of thecurrent study is aimed at controlling the beam acceleration and the relativedisplacement between pier top and beam with the pier damage is ignored. Animproved semi-active control strategy is proposed against this problem. In thisstrategy, the piers damage parameter is introduced into algorithm of limiting Hrovatoptimal semi-active control, so as to control the seismic response of bridges and thepier’s damage at the same time. Several scenarios of a two-span continuous beambridge equipped with MR dampers is numerically simulated with MATLAB tovalidate the proposed semi-active control strategy. The results indicate that thismethod is well capable of controlling the seismic response and reducing the damageindex of the pier simultaneously.(3) A multi-pier joint semi-active control algorithm is proposed. On the basis ofactive optimal control and with the considerartion of the damage state of the continuous beam bridge pier, this control algorithm adjusts the target output ofdampers, in order to control the acceleration of the beam and the relative displacementbetween the top of each pier and the beam making the damage index of each pieraverage at the same time. A three-span continuous beam bridge equipped with MRdampers is numerically studied with MATLAB and several scenarios are simulated tovalidate the proposed semi-active control algorithm. The results indicate that it is wellcapable of controlling the seismic response and effectively reducing the damage indexof the pier which damage is most serious at the mean time, and achieving the effectthat the damage of each pier is evenly distributed to use this multi-pier jointsemi-active control algorithm.(4) A numerical method of the realization of semi-active control in commercialfinite element software ABAQUS is proposed. The traditional method of numericalsimulation on control theories are realized by programming using MATLAB, which isbased on some assumptions and simplification. However, it is difficult to ensure thatthe seismic response of the structure is always in linear elastic state during the processof hazard evolution under strong earthquake so that certain error during suchsimulation is inevitable. One of the main advantages of the method in this dissertationis that the structural plastic response can be taken into better consideration. Theseismic response of a bridge with three-span continuous girder is numerically studiedand the numerical simulation of semi-active control is successfully realized inABAQUS. The proposed method can be used to carry out the refined simulation ofthe seismic response of the structures with semi-active control set, which provides aneffective approach for the research of intelligent control.更多还原