Restoring Initially Cracked Reinforced Concrete Beams utilizing Carbon Fiber Reinforced Polymer Strips

2019 ◽  
Vol 7 (1) ◽  
pp. 30-34
Author(s):  
A. Ajwad ◽  
U. Ilyas ◽  
N. Khadim ◽  
Abdullah ◽  
M.U. Rashid ◽  
...  
Keyword(s):  
Carbon Fiber ◽  
Concrete Beams ◽  
Fiber Reinforced Polymer ◽  
Carbon Fiber Reinforced Polymer ◽  
Fiber Reinforced ◽  
Loading Test ◽  
Control Beam ◽  
Reinforced Polymer ◽  
Cfrp Sheet ◽  
Carbon Fiber Reinforced

Carbon fiber reinforced polymer (CFRP) strips are widely used all over the globe as a repair and strengthening material for concrete elements. This paper looks at comparison of numerous methods to rehabilitate concrete beams with the use of CFRP sheet strips. This research work consists of 4 under-reinforced, properly cured RCC beams under two point loading test. One beam was loaded till failure, which was considered the control beam for comparison. Other 3 beams were load till the appearance of initial crack, which normally occurred at third-quarters of failure load and then repaired with different ratios and design of CFRP sheet strips. Afterwards, the repaired beams were loaded again till failure and the results were compared with control beam. Deflections and ultimate load were noted for all concrete beams. It was found out the use of CFRP sheet strips did increase the maximum load bearing capacity of cracked beams, although their behavior was more brittle as compared with control beam.

Acousto-Ultrasonic Technology for Nondestructive Evaluation of Concrete Bridge Members Strengthened by Carbon Fiber–Reinforced Polymer

2005 ◽  
Vol 1928 (1) ◽  
pp. 245-251 ◽  
Author(s):  
Mahmut Ekenel ◽  
Nestore Galati ◽  
John J. Myers ◽  
Antonio Nanni ◽  
Valery Godínez
Keyword(s):  
Carbon Fiber ◽  
Nondestructive Testing ◽  
Fiber Reinforced Polymer ◽  
Carbon Fiber Reinforced Polymer ◽  
Ultrasonic Nondestructive Testing ◽  
Fiber Reinforced ◽  
Reinforced Polymer ◽  
Wide Range ◽  
Cfrp Sheet ◽  
Carbon Fiber Reinforced

Carbon fiber–reinforced polymer (CFRP) composites have been used in a wide range of application areas in bridge rehabilitations because these materials are less affected by corrosive environmental conditions, are known to provide longer life, and require less maintenance. However, the quality control and quality assessment of these new rehabilitation systems should be further improved and standardized. A recent rehabilitation project that used CFRP laminates was done on a bridge in Dallas County, Missouri, by the Missouri Department of Transportation and the Center for Infrastructure Engineering Studies at the University of Missouri–Rolla. The acousto-ultrasonic nondestructive testing technology was performed to detect and image surface defects in the form of delaminations. These were intentionally formed at the CFRP sheet–concrete interface to investigate the ability of this technique. Acousto-ultrasonic nondestructive testing has shown the ability to detect and image the delaminations between CFRP sheet and concrete substrate.

Friction Loss of Externally Prestressed Concrete Beams with Carbon Fiber-Reinforced Polymer Tendons

2010 ◽  
Vol 163-167 ◽  
pp. 3701-3706 ◽  
Author(s):  
Tian Lai Yu ◽  
Li Yuan Zhang
Keyword(s):  
Friction Coefficient ◽  
Carbon Fiber ◽  
Concrete Beams ◽  
Fiber Reinforced Polymer ◽  
Friction Loss ◽  
Carbon Fiber Reinforced Polymer ◽  
Fiber Reinforced ◽  
Reinforced Polymer ◽  
External Prestressing ◽  
Carbon Fiber Reinforced

Friction loss is an important component of the calculation of prestressing loss for external prestress strengthening technology. Unfortunately, the test data of relevant curvature friction and wobble coefficients is scarce, especially for beams strengthened by external prestressing Carbon Fiber-Reinforced Polymer (CFRP) tendons. Through the experiment of 12 concrete beams strengthened by external prestressing CFRP tendons, this study attempts to discuss the friction loss algorithm and the reasonable value of friction coefficient. The test results demonstrated that traditional friction loss algorithm for prestressed steel tendons is also suit to external prestressing CFRP tendons, but the value of curvature and wobble coefficients should be determined by different types of CFRP tendons and saddle design. What is more, aiming at the domestic production of CFRP tendons and the adopted special saddle design in this paper, the curvature friction coefficient is 0.263 and the wobble coefficient is 0.0067 at the deviator. Results of the research provide a reference for external prestress strengthening design with CFRP tendons.

Sign in / Sign up

Export Citation Format

Share Document