Experimental Study Of T Girder Reinforced With Different Thickness Carbon Fibers

As an important part of transportation infrastructure, bridge is the throat of the transportation. It plays an important role in the transport sector. Maintenance and reinforcement of bridges are increasingly becoming a common problem the world faced by due to lack of design, construction, management, conservation etc, especially in the developing countries. Prestressed carbon fiber technology has been a hot topic in the field of strengthening, and it gets more and more applications in engineering practice which because it both have the advantages of prestressed technology and paste reinforcement technology. However, there are many specifications of the carbon fiber on the market currently with different thickness of 1.2mm, 1.4mm, 2mm, 3mm, 4mm which the width from 30 mm to 200 mm.They have many varieties of sizes and types. The performance of the structural reinforcement is not the same because of the different carbon fiber thickness, especially the impact on the bonding properties of different thickness. It is still a research gaps so far.For this reason, the research team design three different thickness of the carbon fiber of reinforc T beams which with large sizes. Then the auther have an comparative study of the reinforcement test. The first group is the A0 which is an unreinforced beam; the second group is A2 which is reinforced by the carbon fiber of 2mm×50mm(thickness&width); and the third group is reinforced by the carbon fiber of 3mm×50mm(thickness&width). Based on the analysis of the experimental procedure and results and considering the theoretical analysis, we can draw the following conclusions:? Either the 2mm or the 3mm carbon fiber can significantly improve the overall flexural behavior of reinforced concrete beams, includes: the cracking moment, the yield moment and the maximum load capacity.? In terms of the single-layer carbon fiber reinforced, 2mm and 3mm carbon fiber can be very good to work together with the original structure in the entire testing process. It does not appear that the phenomenon of the release which the thick carbon fiber prior to the sheet carbon fiber.? Prestressed carbon fiber reinforces the concrete beams, it can change the flexural rigidity, slow the rise of the neutral axis, reduce the deflection of the midspan respect to the contrast beam which is in the same loads,and it also can delay the crack at the same time. There is an increasing tend of the reducing or the delaying with the increase of the thickness of carbon fiber.? Through theoretical analysis, we can draw that there are three damage modes of the enhanced beam. They are less muscle damage, proper muscle damage and over muscle damage. It will occur over muscle damage and the efficiency of reinforcing will be lower if the amount of the carbon fiber is more. It should be avoided in the design of strengthening.In this article, we have a study on the experimental results and theory of the beams with different thickness of the carbon fiber. The conclusions have a guidance to the reinforce of prestressed carbon fiber.