西北干寒地区桥梁加固方案优选研究及应用

发布时间：2018-05-18 04:08

本文选题：西北干寒地区 + 加固方案优选　；参考：《兰州交通大学》2017年硕士论文

【摘要】：我国现役的公路桥梁中,已有大量旧桥由于原有设计荷载标准低,加上交通运输量和荷载的增加,出现了桥梁承载能力不足、宽度不够的问题,成了技术等级不断提高的公路上的瓶颈路段。对于这些不能满足现代交通需要的公路旧桥,如果全部拆除重建,不仅成本高、工期长,而且会对公路运营带来诸多不便。因此,需要不断加强现有桥梁的维修、养护、加固与改造,恢复或提高其承载能力,保障公路建设的可持续发展。在西北干寒地区,由于恶劣的气候环境加之相对落后的经济水平,公路旧桥的加固问题显得更为严重和迫切。目前我国已有多种成熟的桥梁加固技术,各自有其特点和适用范围;选择加固方案时要考虑方案的技术适应性、加固工期、加固费用、加固效果和对周围环境的影响等;西北干寒地区的桥梁加固方案优选可使稀缺资源得到优化配置,促进经济发展。基于此,本文提出对西北干寒地区在役梁桥加固方案优选进行分析研究,主要内容如下:通过对连霍高速(G30)古浪—瓜州段798座梁桥现有资料的深入分析,总结了西北干寒地区梁桥最常见的病害和产生的原因,针对病害提出加固对策,重点分析了梁桥上部结构常用加固方法的特点和适用性,为其备选加固方案的选用提供了有力参考。通过参考规范、实地调研、查阅文献,提出西北干寒地区梁桥加固方案优选指标体系,计算指标离散程度、重要系数,筛选后形成最终的二级加固方案优选指标体系,包含三个一级指标,十九个二级指标,并明确各个指标的内涵、计算公式和初步处理办法。采用离差最大化的赋权方式将主观AHP权重和客观熵权进行组合,确定了西北干寒地区梁桥加固方案优选指标的权重;在分析众多决策方法的原理和使用范围后选择最适用于方案优选的TOPSIS法,并针对传统TOPSIS法的缺陷,提出基于垂面距离的改进TOPSIS法;建立了西北干寒地区梁桥加固方案优选模型,为选择符合社会性、技术性和经济性要求的加固方案提供了新的思路和方法。针对连霍高速(G30)古浪—瓜州段的嘉峪关K2378+466总寨中桥003加固工程实例,采用基于组合赋权—改进的TOPSIS法加固方案优选模型,对实例中的四种加固方案进行优选,计算结果是粘贴碳纤维布方案最优,这与实际一致,充分说明该加固方案优选模型是有效合理的。本文研究了西北干寒地区桥梁加固方案的优选,一方面为桥梁加固方案优选的区域性研究增添了新成果,另一方面为桥梁管理者提供决策依据,促进了西北干寒地区经济的发展。
[Abstract]:Among the existing highway bridges in our country, due to the low design load standard and the increase of traffic volume and load, a large number of old bridges have the problems of insufficient bearing capacity and insufficient width. It has become the bottleneck section of the highway with increasing technical grade. For these old bridges which can not meet the needs of modern traffic, if all the old bridges are demolished and rebuilt, not only the cost is high, the construction period is long, but also the highway operation will be inconvenient. Therefore, it is necessary to strengthen the maintenance, reinforcement and reconstruction of existing bridges, restore or improve their bearing capacity, and ensure the sustainable development of highway construction. In the dry and cold region of Northwest China, due to the bad climate environment and the relatively backward economic level, the reinforcement of old highway bridges is more serious and urgent. At present, there are many mature bridge reinforcement technologies in our country, each of them has its own characteristics and applicable scope, the technical adaptability of the scheme, the time limit, the cost, the effect of reinforcement and the influence on the surrounding environment should be considered when selecting the reinforcement scheme. The optimal selection of bridge reinforcement scheme in northwest dry and cold regions can optimize the allocation of scarce resources and promote economic development. Based on this, this paper puts forward an analysis and study on the optimal selection of existing beam bridge reinforcement schemes in the northwest dry and cold region. The main contents are as follows: through the in-depth analysis of the existing data of 798 beam bridges in Gulang-Guazhou section of Lianghuo High-Speed G30, This paper summarizes the most common diseases and causes of beam bridges in the dry and cold region of northwest China, puts forward the reinforcement countermeasures against the diseases, and emphatically analyzes the characteristics and applicability of the commonly used reinforcement methods for the superstructure of the beam bridges. It provides a powerful reference for the selection of alternative reinforcement schemes. Based on the reference criterion, field investigation and literature review, this paper puts forward the optimal selection index system of beam bridge reinforcement scheme in the dry and cold region of northwest China, calculates the degree of dispersion and important coefficient of the index, and forms the final optimal selection index system of the second grade reinforcement scheme after screening. It includes three primary indexes and nineteen secondary indexes, and defines the connotation, calculation formula and preliminary treatment method of each index. The subjective AHP weight and objective entropy weight are combined to determine the weight of the optimal selection index of beam and bridge reinforcement scheme in the dry and cold region of Northwest China by using the weighted method of maximizing deviation. After analyzing the principle and application range of many decision methods, the TOPSIS method, which is the most suitable for scheme selection, is selected. Aiming at the defects of traditional TOPSIS method, an improved TOPSIS method based on vertical plane distance is put forward, and an optimal selection model of beam bridge reinforcement scheme is established in the dry and cold region of Northwest China. New ideas and methods are provided for the selection of reinforcement schemes that meet the social, technical and economic requirements. Aiming at the example of Jiayuguan K2378,466 Zongzhai Bridge 003 reinforcement project in Gulang-Guazhou section of Lianhuo High-speed G30, the optimal selection model of reinforcement scheme based on combined weighting and improved TOPSIS method is adopted, and the four reinforcement schemes in the example are selected optimally. The result of calculation is that the scheme of bonded carbon fiber cloth is optimal, which is consistent with the actual situation, which fully shows that the optimal selection model of the reinforcement scheme is effective and reasonable. This paper studies the optimal selection of bridge reinforcement schemes in the dry and cold region of Northwest China. On the one hand, it adds new results to the regional study of bridge reinforcement schemes, on the other hand, it provides a basis for bridge managers to make decisions. Promoted the northwest dry cold area economic development.
【学位授予单位】：兰州交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U445.72

【参考文献】