预应力碳纤维板加固受损构件试验研究

发布时间：2018-05-26 02:31

本文选题：受损构件 + 碳纤维板　；参考：《重庆交通大学》2014年硕士论文

【摘要】：桥梁作为地区经济发展的纽带，在公路交通中起着举足轻重的作用。然而，由于长期累积损伤，或者因偶然荷载，如地震、超载等原因造成部分桥梁受损严重，那么紧急、快速、有效的桥梁加固技术就显得非常重要。预应力碳纤维板快速加固技术是一种主动加固技术，它集成了粘贴碳纤维加固技术和预应力加固技术的优点，能够实现对桥梁结构的快速、有效的加固处治，是目前国内外研究的热点和前沿，，也是应用前景非常广阔的一种加固技术。在以往进行的预应力碳纤维板加固试验研究中，大部分都是针对结构状态相对比较好的构件进行加固，对受损严重的构件的加固试验还未见公开的文献报道，所以本文试验研究了1片严重受损（裂缝宽度达到1.5mm）的混凝土T梁构件，经预应力碳纤维板加固后，其承载能力、变形性能的发生显著改善，经试验研究，得到如下重要成果： ①虽然严重受损构件的初始裂缝宽度较大，但经预应力碳纤维板加固后，裂缝宽度显著减小，且对碳纤维板预应力的放张损失及长期损失进行观测表明预应力长期损失非常小，不足三次张拉应力的1%。 ②在整个试验加载过程中，且直到上缘混凝土最终压溃，碳纤维板都没有发生锚固失效，且碳纤维板与构件也未发生剥离，碳纤维板保持完好，碳纤维板与T梁构件共同工作性能较好，加固效果接近正常一般微损伤构件的加固，说明预应力碳纤维板快速加固能较好恢复和提高原结构的承载力和受力性能。 ③理论分析表明，采用平截面假定及内力平衡为基础的计算结果与试验结果吻合良好，说明以传统的平截面假定为基础的力学模型可以较好的预测经过预应力碳纤维板加固的受弯构件的工作性能。以上对受损严重构件的快速加固研究，对桥梁抢险、抗震救灾等紧急情况下桥梁的快速承载能力恢复具有很强的工程应用价值。
[Abstract]:As the link of regional economic development, bridge plays an important role in highway traffic. However, due to long-term cumulative damage, or due to accidental loads, such as earthquake, overload and other reasons causing serious damage to some bridges, then urgent, rapid, effective bridge reinforcement technology is very important. The fast strengthening technology of prestressed carbon fiber slab is a kind of active reinforcement technology. It integrates the advantages of bonded carbon fiber reinforcement technology and prestressed reinforcement technology, and can realize the fast and effective reinforcement of bridge structure. It is the hot spot and frontier of domestic and international research at present, and it is also a kind of reinforcement technology with very broad application prospect. In the previous experimental study of prestressed carbon fiber slab reinforcement, most of them are aimed at the relatively good structural members. The experimental results of the severely damaged members have not been reported in the public literature. Therefore, this paper tests and studies a seriously damaged concrete T-beam member (crack width up to 1.5mm). After strengthening with prestressed carbon fiber slab, the bearing capacity and deformation performance of the member are improved significantly. The experimental results are as follows: (1) although the initial crack width of severely damaged members is large, the crack width decreases significantly after strengthening with prestressed carbon fiber slab, and the long term loss of prestressing force is very small. Less than one part of three tensile stresses. 2 during the whole test loading process, and until the upper edge concrete finally collapses, there is no Anchorage failure of the carbon fiber plate, and the carbon fiber plate and the member are not stripped, the carbon fiber plate remains intact, The performance of CFRP and T-beam members is good, and the strengthening effect is close to that of normal micro-damage members, which indicates that the rapid strengthening of prestressed CFRP plate can recover and improve the bearing capacity and mechanical performance of the original structure. (3) theoretical analysis shows that the calculated results based on plane section assumption and internal force balance are in good agreement with the experimental results. It shows that the mechanical model based on the traditional plane section assumption can predict the working performance of flexural members strengthened with prestressed carbon fiber sheet. The above research on the rapid reinforcement of severely damaged components has a strong engineering application value to bridge emergency rescue, earthquake relief and other emergency situations, such as rapid recovery of the bearing capacity of bridges.
【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U445.72

【参考文献】