多塔缆索承重桥梁纵向结构体系的减震控制方法研究

发布时间：2018-04-19 10:23

本文选题：多塔缆索承重桥梁 + 纵向结构体系　；参考：《东南大学》2015年硕士论文

【摘要】：多塔缆索承重桥梁纵向结构主要有飘浮体系、全固结体系和部分固结体系。深入研究多塔缆索承重桥梁纵向结构体系的抗震性能及其减震控制方法,提高其安全运营与抵抗地震的能力,是桥梁工程领域亟待解决的问题之一。本文以嘉绍大桥和琼州海峡斜拉桥为工程背景,分析研究了不同纵向结构体系对多塔缆索承重桥梁抗震性能的影响,针对不同纵向结构体系提出了多种被动减震控制方案并进行比较分析,最后利用响应面法和多目标遗传算法进行了减震优化控制方法研究。本文的主要工作和成果如下：1.基于Ansys软件平台建立了嘉绍大桥和琼州海峡斜拉桥的有限元模型,采用分块Lanczos法计算了不同纵向结构体系有限元模型的静动力特性。研究结果表明,不同纵向结构体系主要改变多塔缆索承重桥梁主梁的竖弯和侧弯刚度,从全固结体系过渡到飘浮体系,主梁弯曲刚度降低,相应的自振周期有所延长；并且不同纵向结构体系对主梁竖弯振型和侧弯振型影响较大,但对主塔侧弯振型和主梁扭转振型影响很小。2.利用Ansys平台对开展了地震作用下的多塔缆索承重桥梁地震反应分析,对比了不同纵向结构体系的桥梁结构抗震性能。研究结果表明：飘浮体系的塔顶纵向位移、塔梁和墩梁纵向相对位移等位移反应较大,而塔底纵向内力反应较小；全固结体系的塔底纵向内力反应较大,而塔顶纵向位移、塔梁和墩梁纵向相对位移等位移反应较小；部分固结体系有其独特的力学性能,位移反应较小,塔梁纵向自由处的塔底纵向内力反应亦较小,然而塔梁纵向固结处的塔底纵向内力反应则较大。3.针对纵向飘浮体系和部分固结体系提出了多种减震控制方案,分析比较了不同减震控制方案的控制效果。分析结果表明：塔梁间设置弹性拉索或粘滞流体阻尼器可以显著减小桥梁纵向位移响应,但对桥塔纵向内力有一定的放大作用：为取得较好的控制效果需设置合理的减震装置参数；综合运用弹性拉索与粘滞流体阻尼器时,两种装置可以协同工作,取得更好的控制效果。4.将响应面法及多目标遗传算法相结合,对多塔缆索承重桥梁纵向飘浮体系阻尼器减震方案和部分固结体系混合方案进行了减震优化控制方法研究。分析结果表明响应面法拟合所得减震响应面效果较为理想,可用于地震响应控制的优化设计中；利用多目标遗传算法进行的减震方案优化分析,并得到了优化控制结果。
[Abstract]:The longitudinal structure of multi-tower cable bearing bridges mainly includes floating system, fully consolidated system and partial consolidation system.It is one of the urgent problems in bridge engineering field to deeply study the seismic performance and vibration absorption control method of the longitudinal structure system of multi-tower cable bearing bridge to improve its ability of safe operation and earthquake resistance.Taking Jiazhao Bridge and Qiongzhou Strait Cable-Stayed Bridge as the engineering background, the influence of different longitudinal structural systems on the seismic behavior of multi-tower cable-bearing bridges is analyzed and studied in this paper.A variety of passive vibration control schemes for different longitudinal structure systems are proposed and compared and analyzed. Finally, response surface method and multi-objective genetic algorithm are used to study the optimal control method.The main work and results of this paper are as follows: 1.Based on the Ansys software platform, the finite element models of Jiazhao Bridge and Qiongzhou Strait Cable-Stayed Bridge are established, and the static and dynamic characteristics of the finite element models of different longitudinal structural systems are calculated by block Lanczos method.The results show that the vertical bending and lateral bending stiffness of the main girder of multi-tower cable bearing bridge are mainly changed by different longitudinal structural systems, and the bending stiffness of the main beam decreases and the corresponding natural vibration period is prolonged from the fully consolidated system to the floating system.Different longitudinal structure systems have great influence on the vertical bending mode and lateral bending mode of the main beam, but have little effect on the lateral bending mode of the main tower and the torsional mode of the main beam.The seismic response analysis of multi-tower cable bearing bridges under earthquake action is carried out by using Ansys platform, and the seismic behavior of bridge structures with different longitudinal structure systems is compared.The results show that the longitudinal displacement of the tower top, the relative displacement of the tower beam and the pier beam is greater than that of the bottom of the tower, but the response of the longitudinal internal force of the tower bottom is small, that of the fully consolidated system is greater than that of the tower top.The displacement response of the tower beam and the pier beam is relatively small, the partial consolidation system has its unique mechanical properties, the displacement response is small, and the longitudinal internal force response of the tower bottom at the longitudinal free place of the tower beam is also smaller.However, the longitudinal internal force response of the tower bottom at the longitudinal consolidation of the tower beam is larger than that of the tower beam.For longitudinal floating system and partial consolidation system, a variety of shock absorption control schemes are proposed, and the control effects of different shock absorption control schemes are analyzed and compared.The results show that elastic cables or viscous fluid dampers can significantly reduce the longitudinal displacement response of the bridge.But it can amplify the longitudinal internal force of the bridge tower: in order to obtain better control effect, it is necessary to set reasonable parameters of shock absorber, and when the elastic cable and viscous fluid damper are used synthetically, the two devices can work together.Achieve better control effects.The response surface method and multi-objective genetic algorithm are combined to study the damping scheme of longitudinal floating system of multi-tower cable bearing bridge and the hybrid scheme of partial consolidation system.The results show that the response surface fitted by the response surface method is more effective and can be used in the optimal design of seismic response control, and the optimization analysis of the seismic response control scheme based on multi-objective genetic algorithm is carried out, and the optimal control results are obtained.
【学位授予单位】：东南大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U442.55

【相似文献】