基于健康监测的辽河大桥斜拉索索力的研究

发布时间：2018-03-04 16:25

本文选题：健康监测　切入点：成桥索力　出处：《沈阳大学》2017年硕士论文　论文类型：学位论文

【摘要】：近些年,国内外大跨径斜拉桥建造的数量越来越多。斜拉桥是一种桥面体系受压、支撑体系受压的结构体系,斜拉桥比梁式桥具有更大的跨越能力,这使得其在设计和施工过程中存在比普通梁式桥更大的难度,故确定斜拉桥合理的施工状态对斜拉桥施工过程中的结构安全、主梁线型合理至关重要[1]。因此,对于索力的设计是斜拉桥设计和施工过程中的关键问题。本文在基于辽河大桥的健康监测系统上,对斜拉桥的索力进行了深入研究,其研究内容包括:健康监测系统的构成和存在的问题;斜拉桥成桥索力的优化;钢箱梁温度场对斜拉桥索力的影响;斜拉索疲劳损伤分析与研究。主要内容如下:第一,介绍辽河大桥健康监测系统的构成,并列举了几个确定合理成桥索力的实用方法,为本文的数据分析以及Midas/Civil数据模拟提供工程背景。第二,提出了优化索力的一种综合方法,该方法是通过对目前现有的优化成桥索力的方法进行整合,利用每种优化方法的优点来对成桥索力进行优化。该方法可以通过对斜拉桥成桥索力进行多步骤、多目标的优化过程来对其进行优化,从而得到更加精细和符合成桥状态的合理成桥索力。第三,运用本文提到的综合法来对辽河大桥的成桥索力进行优化。经过运用该方法优化后的索力分布均匀,局部索力参差不齐以及主塔附近变化较大的情况得到了明显的改善,主梁恒载弯矩合理,受力情况合理,整体受力性能得到明显提高;主塔恒载作用下位移大大减小,对控制主塔的偏移起到了一定的作用。第四,通过运用健康监测系统对钢箱梁斜拉桥的温度场和索力进行监测,深入研究了辽河大桥钢箱梁在温度作用下所产生的温度效应对索力的影响情况。研究结果表明:温度变化与索力变化呈现出正比关系,并对温度场中的室外温度和索力进行同一时间段的曲线拟合,得到温度满足正弦函数,而索力每天的前6小时满足线性关系,后18小时满足高斯分布。通过比较夏季和冬季的索力差值,得到温度变化越大对索力影响越大的关系。最后,对斜拉索进行疲劳损伤分析,由数据分析可知,当风速增大时,风偏角相同的情况下,拉索的损伤也随之增大,反之,当风速减小的时候,拉索的损伤也随之减小。对辽河大桥的斜拉索疲劳损伤估计起到一定的作用。
[Abstract]:In recent years, more and more long-span cable-stayed bridges have been built at home and abroad. Cable-stayed bridges are a kind of structural system where the deck system is compressed and the bracing system is compressed. The cable-stayed bridge has more span capacity than the girder bridge. This makes the design and construction of cable-stayed bridge more difficult than that of ordinary girder bridge. Therefore, determining the reasonable construction state of cable-stayed bridge is very important to the structural safety of cable-stayed bridge during construction, and the reasonable alignment of main beam is very important. The design of cable force is a key problem in the design and construction of cable-stayed bridge. In this paper, the cable force of cable-stayed bridge is deeply studied in the health monitoring system based on Liaohe Bridge. The research contents include: constitution and existing problems of health monitoring system; optimization of cable force of cable-stayed bridge; influence of temperature field of steel box girder on cable force of cable-stayed bridge; fatigue damage analysis and research of cable-stayed bridge. The main contents are as follows: first, This paper introduces the constitution of the health monitoring system of Liaohe Bridge, and enumerates several practical methods for determining the rational cable force of the bridge, which provides the engineering background for the data analysis and Midas/Civil data simulation in this paper. Secondly, a comprehensive method for optimizing cable force is proposed. In this method, the cable force of the bridge is optimized by integrating the existing methods to optimize the cable force of the bridge, and the advantages of each optimization method are used to optimize the cable force of the cable-stayed bridge. Multi-objective optimization process to optimize it, so as to obtain a more refined and consistent with the bridge state of the reasonable cable force. Third, The cable force of Liaohe Bridge is optimized by using the comprehensive method mentioned in this paper. The distribution of cable force is uniform, the local cable force is uneven and the variation of the main tower is large. The bending moment of the main beam under dead load is reasonable, the stress condition is reasonable, the overall mechanical performance is obviously improved, the displacement of the main tower is greatly reduced under the action of dead load, which plays a certain role in controlling the deviation of the main tower. 4th, The temperature field and cable force of cable-stayed bridge with steel box girder are monitored by using health monitoring system. The effect of temperature on the cable force of the steel box girder of Liaohe Bridge is studied. The results show that the change of temperature is proportional to the change of cable force. The curve fitting of outdoor temperature and cable force in the temperature field in the same time period shows that the temperature satisfies the sine function, and the cable force satisfies the linear relationship in the first 6 hours of each day. After 18 hours, Gao Si distribution is satisfied. By comparing the difference of cable force in summer and winter, the relationship between temperature change and cable force is obtained. Finally, fatigue damage analysis of stay cable is carried out. From the data analysis, it can be seen that when wind speed increases, When the wind angle is the same, the cable damage also increases, on the contrary, when the wind speed decreases, the cable damage also decreases, which plays a certain role in the estimation of the cable fatigue damage of Liaohe Bridge.
【学位授予单位】：沈阳大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U448.27

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