不同厚度碳纤维板加固T梁的试验研究

发布时间：2018-04-26 04:07

本文选题：碳纤维板 + 波形锚　；参考：《重庆交通大学》2015年硕士论文

【摘要】：桥梁作为基础设施的重要组成部分,是交通运输的咽喉,起着举足轻重的作用。由于设计、施工、管理、养护等方面的不足,桥梁维修与加固越来越成为全世界共同面临的一个问题,在发展中国家尤为突出。预应力碳纤维板技术由于兼具预应力技术和粘贴加固技术的双重优势,已经成为加固领域的研究热点,并在工程实践中得到了越来越多的应用。然而,目前市场上碳纤维板的规格较多,厚度有1.2mm、1.4mm、2mm、3mm、4mm,宽度从30mm到200mm,等等多种规格和种类。不同的碳纤维板厚度,对结构加固的性能是不一样的,特别是厚度不同对粘结性能的影响,到目前为止,还是一个研究空白。为此,本研究团队设计了三组不同厚度碳纤维板加固大尺寸T梁的加固试验进行对比研究,第一组A0为未加固梁,第二组A2为2mm×50mm(厚×宽)碳纤维板加固,第三组A3为3mm×50mm(厚×宽)碳纤维板加固。通过对试验过程和结果进行分析,并进行理论推导,得出以下结论:①无论是2mm碳板还是3mm碳板都显著的提高了钢筋混凝土梁的整体抗弯性能,包括:开裂弯矩、屈服弯矩、最大承载能力。②就单层预应力碳纤维板加固而言,2mm和3mm碳纤维板在整个试验过程中都能与原结构很好的共同工作,未出现厚碳纤维板先于薄板剥离的现象。③预应力碳纤维板加固钢筋混凝土梁,可以改变其抗弯刚度,延缓中和轴上升,使得同等荷载作用下的跨中挠度相对于对比梁有所减小,并使得裂缝发展有所延缓,同时,随着碳板厚度的增加,减小或延缓程度有增加的趋势。④理论研究表明,预应力碳纤维板加固后的梁,可将受弯构件正截面破坏划分为三种不同的形式:少筋破坏、适筋破坏、超筋破坏,加固量较大,将出现超筋破坏,加固效率降低,在加固设计中应尽量避免。本文对不同厚度碳纤维板加固的构件的试验成果和理论进行研究,结论对预应力碳纤维板加固设计具有指导意义。
[Abstract]:As an important part of infrastructure, bridge is the throat of transportation and plays an important role. Due to the deficiency of design, construction, management and maintenance, bridge maintenance and reinforcement have become a common problem all over the world, especially in developing countries. The technology of prestressed carbon fiber sheet has become a hot spot in the field of reinforcement because of its dual advantages of both prestressing technology and bonding and strengthening technology, and has been applied more and more in engineering practice. However, there are many specifications of CFRP in the market at present, with a thickness of 1.2mm / 1.4mm / 2mm / 3mm / 4mm, width from 30mm to 200mm, and so on. The effect of different thickness of CFRP on structural strengthening performance is different, especially the influence of different thickness on bond performance, so far, there is still a blank in the study. Therefore, this research team designed three groups of different thickness carbon fiber sheet to strengthen the large size T beam to carry on the contrast research, the first group A0 is the unstrengthened beam, the second group A2 is the 2mm 脳 50mm (thickness 脳 width) carbon fiber plate reinforcement, the second group is the 2mm 脳 50mm (thickness 脳 width) carbon fiber plate reinforcement. The third group A 3 is 3mm 脳 50 mm (thick 脳 wide) carbon fiber sheet reinforcement. Through the analysis of the test process and results, and the theoretical derivation, the following conclusions are drawn: both the 2mm carbon plate and the 3mm carbon plate can significantly improve the overall flexural behavior of the reinforced concrete beam, including: cracking moment, yield moment, The maximum bearing capacity of 2 mm and 3mm carbon fiber sheet can work well with the original structure during the whole experiment. The phenomenon that thick carbon fiber slab is not peeled off before thin plate... The bending stiffness of reinforced concrete beam strengthened by prestressed carbon fiber slab can be changed, and the rise of neutral axis can be delayed. Under the same load, the mid-span deflection is reduced relative to the contrast beam, and the crack development is retarded. At the same time, with the increase of carbon plate thickness, the decreasing or delaying degree is increasing. The beam strengthened with prestressed carbon fiber slab can be divided into three different types: the failure of less reinforcement, the failure of suitable reinforcement, the failure of overreinforcement, the large amount of reinforcement, and the decrease of reinforcement efficiency. The reinforcement design should be avoided as far as possible. In this paper, the experimental results and theory of different thickness CFRP strengthened members are studied, and the conclusion is of guiding significance for the design of prestressed CFRP plates.
【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U445.72

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