基于实时监测的混凝土梁桥安全性能快速评估方法研究

发布时间：2018-07-14 09:53

【摘要】：伴随着我国交通物流的快速发展,应用最为广泛的混凝土梁式桥出现了越来越多的病害。及时发现桥梁病害,防止桥梁的安全性能进一步退化并及时进行维修加固,对既有桥梁进行安全性能快速评估就显得尤为重要。本文以沈海高速(G15)江苏段烈士河大桥为工程背景,主要进行的工作如下：(1)建立烈士河大桥健康监测系统,并对系统采集到的数据进行了系统的分析。(2)基于环境振动试验的结果,对烈士河大桥初始有限元模型进行了修正,建立了能够反映烈士河大桥实际运营状态的基准有限元模型,进而为烈士河大桥建立安全评估的阈值。(3)基于不确定层次分析法、群判断、集值统计原理、变权综合以及熵值法等理论建立了烈士河大桥安全评估模型,自行开发了桥梁安全综合性能评估软件,并使用该软件对烈士河大桥进行了安全评估。(4)推导了两跨连续梁桥的挠度影响线及其一、二阶导数的表达式,建立了基于挠度影响线的桥梁承载力初步评定方法,并进行了算例验证。(5)应用常丁Ar—η回归模型和在线健康监测系统的实测数据,研究了动挠度影响线与实时车辆荷载相结合的桥梁承载力快速评定方法,并采用该方法对烈士河大桥进行承载力评估。得到的主要结论如下：(1)烈士河大桥结构健康监测系统具有功能完整性、维修养护方便性、先进实用性等特点,监测结果符合部分预应力混凝土连续梁桥的基本力学行为,达到了健康监测系统设计的基本要求,可为烈士河大桥安全评估的研究提供有力支撑。(2)基于环境振动试验和三阶响应面方法,进行了烈士河大桥有限元模型修正,计算模态与实测模态吻合较好,修正后的烈士河大桥有限元模型可作为烈士河大桥安全评估的基准有限元模型。(3)建立了烈士河大桥安全综合评估模型,开发了基于Matlab的安全综合评估软件；烈士河大桥7个月安全评估平均得分为89.3分,表明烈士河大桥大桥安全状况良好。(4)建立了基于挠度影响线的桥梁承载力初步评定方法,可以用于桥梁损伤识别和承载力评估。(5)基于实时监测和基于动挠度影响线的在线模型修正方法,建立了烈士河大桥极限承载力的快速评估方法。评估结果表明：烈士河大桥处于安全的工作性能状态,极限承载力安全系数在3.5以上。
[Abstract]:With the rapid development of transportation logistics in China, more and more diseases appear in the most widely used concrete beam bridges. It is very important to find the bridge diseases in time to prevent the safety performance of the bridge from degenerating further and to carry on the maintenance and reinforcement in time. So it is very important to evaluate the safety performance of the existing bridges quickly. The main work of this paper is as follows: (1) establish the health monitoring system of the Shenhai Highway (G15) Martyrs River Bridge in Jiangsu Province, the main work of this paper is as follows: (1) establish the Health Monitoring system of the Martyrs River Bridge. And the data collected by the system are systematically analyzed. (2) based on the results of the environmental vibration test, the initial finite element model of the Martyrs River Bridge is modified, and the benchmark finite element model which can reflect the actual operation state of the Martyr River Bridge is established. Then the threshold value of safety assessment is established for the Martyrs River Bridge. (3) based on the theory of uncertain Analytic hierarchy process (AHP), group judgment, set value statistics principle, variable weight synthesis and entropy method, the safety assessment model of Martyrs River Bridge is established. The comprehensive performance evaluation software for bridge safety is developed, and the safety evaluation of the Martyr River Bridge is carried out by using the software. (4) the expressions of the deflection influence line and the first and second derivative of the two-span continuous beam bridge are derived. A preliminary evaluation method of bridge bearing capacity based on deflection influence line is established, and an example is given to verify it. (5) the Ar- 畏 regression model of Changding and the measured data of on-line health monitoring system are used. In this paper, the rapid evaluation method of bridge bearing capacity combined with dynamic deflection influence line and real time vehicle load is studied, and the method is used to evaluate the bearing capacity of the Martyr River Bridge. The main conclusions are as follows: (1) the structural health monitoring system of the Martyrs River Bridge has the characteristics of functional integrity, convenient maintenance, advanced practicability and so on. The monitoring results accord with the basic mechanical behavior of partially prestressed concrete continuous beam bridge. It meets the basic requirements of the health monitoring system design and can provide a strong support for the study of the safety assessment of the Martyrs River Bridge. (2) based on the environmental vibration test and the third order response surface method, the finite element model of the Martyrs River Bridge is modified. The modified finite element model of the Martyrs River Bridge can be used as the benchmark finite element model for the safety assessment of the Martyrs River Bridge. (3) the comprehensive safety assessment model of the Martyrs River Bridge is established. The software of comprehensive safety assessment based on Matlab is developed, and the average score of safety assessment for the Martyrs River Bridge in 7 months is 89.3, which indicates that the safety condition of the Bridge is good. (4) A preliminary assessment method of bridge bearing capacity based on deflection influence line is established. It can be used to identify the damage and evaluate the bearing capacity of bridges. (5) based on real-time monitoring and on-line model modification method based on dynamic deflection influence line, a fast evaluation method for ultimate bearing capacity of Martyr River Bridge is established. The evaluation results show that the Martyrs River Bridge is in a safe working condition and the safety factor of ultimate bearing capacity is above 3.5.
【学位授予单位】：东南大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：U446

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