PC箱梁桥施工期可靠度研究

发布时间：2018-04-28 17:06

本文选题：悬臂施工 + 可靠指标　；参考：《湖南科技大学》2015年硕士论文

【摘要】：将可靠度理论融入工程的设计、施工、运营中是当今国内外工程结构发展的必然趋势。本文以从化市花卉大道大桥为工程背景,将可靠度理论应用到桥梁施工监控过程中。同时结合现场实测数据,对花卉大桥的可靠性进行研究,具体研究内容如下:1、通过对施工现场混凝土容重、立方体抗压强度以及回弹数据的采集,分析这三项随机变量的概率分布。2、采集张拉前后的目标截面的应力数据和张拉伸长量数据,求出预应力钢束中的有效预应力值,进而分析得到有效预应力偏差值的概率分布函数。3、运用现场采集到的数据,对花卉大桥的施工期抗力和荷载效应进行了分析,建立了该桥施工过程中最大悬臂端承载能力极限失效模式下的抗力概率模型和荷载概率模型。4、分析了计算模式、混凝土抗压强度、钢筋强度、恒载、施工活载这五种随机变量对可靠指标的影响,结果表明对可靠指标影响最大的随机变量为计算模式和混凝土抗压强度;其次为恒载和钢筋强度;而施工活载对结构可靠指标几乎没有影响。5、分析了混凝土抗压强度、恒载、施工活载、有效预应力等随机变量在混凝土受压失效模式下对结构的可靠指标的影响,结果表明混凝土受压失效模式下对结构的可靠指标略大于目标可靠指标,分析表明混凝土的抗压强度对该失效模式可靠指标影响最大,其次是有效预应力和容重。
[Abstract]:It is an inevitable trend to integrate reliability theory into the design, construction and operation of engineering structures at home and abroad. Based on the Flower Avenue Bridge in Conghua City, this paper applies the reliability theory to the monitoring process of bridge construction. At the same time, the reliability of Flower Bridge is studied based on the field measured data. The specific research contents are as follows: 1. Through the collection of concrete bulk density, cube compressive strength and springback data in the construction site, The probability distribution of these three random variables is analyzed. The stress data and tensile elongation data of the target section before and after tensioning are collected, and the effective prestressing value in prestressed steel bundle is obtained. Then, the probability distribution function of effective prestress deviation value is obtained. Using the data collected on the spot, the resistance and load effect during the construction period of Flower Bridge are analyzed. The resistance probability model and load probability model of the bridge under the limit failure mode of the maximum cantilever end bearing capacity during the construction of the bridge are established. The calculation model, the compressive strength of concrete, the strength of steel bar, and the dead load are analyzed. The results show that the most influential random variables are the calculation model and the compressive strength of concrete, followed by the dead load and the strength of steel bar. However, the construction live load has little effect on the structural reliability index. 5. The influence of random variables such as concrete compressive strength, dead load, construction live load and effective prestress on the structural reliability index under the failure mode of concrete compression is analyzed. The results show that the reliability index of concrete under compressive failure mode is slightly larger than that of target reliability index. The analysis shows that the compressive strength of concrete has the greatest influence on the reliability index of the failure mode, followed by effective prestress and bulk density.
【学位授予单位】：湖南科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U445;U446

【共引文献】