混凝土无损检测在旧桥承载能力评定中的应用(任务书,开题报告,外文翻译,论文21000字)
摘要
迄今,我国桥梁建设取得了令人侧目的成就,我国的在役桥梁有80万座左右,4592万延米。另外由于时代的进步,我国的交通事业迅速发展,进而交通荷载在之前的基础上进一步增大,使大批进入老化期的在役桥梁结构(也就是所谓的旧桥)难堪其负。再加上当时因桥梁施工材料等级标准模糊以及桥梁荷载设计等级较低,以及随着桥龄的增长,很大一部分部分桥梁出现不同程度的损伤且有加剧趋势,所以对于公路主线上的重要桥梁的桥梁等级的提高已刻不容缓,尤其是国道上的桥梁急需提高等级(如由汽-20提高到公路Ⅰ级)。因此,对旧桥的承载能力的评定的工作就非常重要。本文以福建省的游绳渡大桥(旧桥)为例,讨论混凝土无损检测对旧桥承载能力的评定的影响。
(1)阐述了国内外旧桥承载能力的发展历史,介绍了国内外相关的桥梁检测的成果和桥梁评估的主要方法;
(2)结合游绳渡大桥实际检测项目,采用MIDAS有限元软件,建立了该桥有限元分析模型,对其受力特性进行分析,包括成桥阶段主梁竖向位移和内力计算,讨论了结构受力的特点;
(3)对游绳渡大桥开展了针对性的外观和无损检测工作,并对其做了评估分析;
(4)制定了游绳渡大桥荷载试验方案,开展了现场试验检测工作,通过荷载试验各项指标结果,对桥梁承载能力进行了评估。
关键词:荷载试验、无损检测、桥梁承载能力评估、承载能力检算系数
Abstract
So far, remarkable achievements have been made in the construction of bridges in our country, with about 800,000 bridges in service and 45.92 million linear meters. In addition, due to the progress of the times, China's transportation industry has developed rapidly, and the traffic load has further increased on the basis of the previous, making a large number of in-service bridge structures (the so-called old bridges) entering the aging period embarrassing theirnegative effects. In addition, at that time, due to the vague standard of bridge construction materials and the lower design grade of bridge load, as well as with the growth of bridge age, a large part of bridges suffered various degrees of damage and showed an increasing trend, so the improvement of some important bridge grades was urgent, especially for the bridges on the national highway, which needed to be upgraded urgently (for example, from steam -20 to highway grade I). Therefore, it is very important to evaluate the bearing capacity of old bridges. Taking Youshengdu Bridge (old bridge) in Fujian Province as an example, this paper discusses the influence of concrete nondestructive testing on the evaluation of old bridge bearing capacity.
(1) The development history of the bearing capacity of old bridgesat home and abroad has been elaborated , and the results of relevant bridge inspection at home and abroad, as well as the main methods of bridge evaluation have been introduced in this paper.
(2) With the combination of project of Youshengdu Bridge ,the finite element analysis model of concrete bridge is established by MIDAS finite element software to analyze its stress characteristics, including the calculation of vertical displacement and internal force of the main girder during the completion phase, and the mechanical characteristics of the structure are discussed.
(3) Targeted external appearance and non-destructive testing work were carried out for Youshengdu Bridge, and its evaluation and analysis were carried out.
(4) The load test scheme of Youshengdu Bridge was established, and the field test was carried out. The bearing capacity of the bridge was evaluated through the results of various indexes of the load test.
Key Words:Load test, nondestructive testing, bridge bearing capacity evaluation, bearing capacity calculation coefficient
目录
第一章绪论 1
1.1引言 1
1.2研究现状 2
1.2.1桥梁承载能力的基本评估方法 3
1.2.2桥梁检测的内容 4
1.2.3本文研究内容 5
第二章桥梁检测方法 6
2.1检测目的 6
2.2桥梁缺损情况检测以及检测方法 6
2.2.1公路桥梁分类 6
2.2.2公路桥梁检测内容 7
2.2.3桥梁构件和部件技术状况评分 7
2.2.4构件技术状况评分说明 8
第三章桥梁检测过程 10
3.1工程概况 10
3.2检测仪器 11
3.3外观检测过程 11
3.4无损检测过程 13
3.5荷载试验检测过程 13
3.5.1静载试验 13
3.5.2动载试验 19
第四章游绳渡大桥检测 21
4.1右幅检测结果 21
4.1.1桥面系检测结果 22
4.1.2上部结构检测结果 24
4.1.3下部结构检测结果 27
4.2无损检测结果 28
4.2.1全桥的技术状况评定结果 28
4.2.2左幅 30
4.2.3混凝土强度检测结果 30
4.2.4钢筋锈蚀电位检测 31
4.2.5钢筋保护层厚度检测 31
4.2.6混凝土碳化深度检测 31
4.3荷载试验结果 34
4.3.1静载试验结果 34
4.3.2静载结果评定 46
4.3.3动载试验结果 48
4.4桥梁检算 52
4.4.1检算原则 52
4.4.2相关参数确定 52
4.4.3分析方法 53
4.5验算 53
4.5.1计算受压区高度 53
4.5.2正截面抗弯承载力计算表 54
4.5.2桥梁评定结果 55
第五章总结 56
参考文献: 57
致谢: 58 |