Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : Strengthening


Effect of Wetting and Drying Cycles on Behavior of Concrete Externally Strengthened with CFRP Laminates

D.H. Mohammed; T.S. Al-Attar; H.A. Dawood

Engineering and Technology Journal, 2017, Volume 35, Issue 7, Pages 675-684

This study describes an experimental work that was made to evaluate the effect of wetting and drying cycles on the behavior of concrete specimens externally strengthened with CFRP laminates. The experimental work included testing of twenty-three concrete specimens externally strengthened with CFRP laminates in different positions, with two compressive strength levels. The experimental variables considered in the test program include, compression strength of concrete, number of carbon fiber reinforced polymer (CFRP) strip layers, using CFRP strips throughout the total length of the specimen or within the middle third, and the number of wetting and drying cycles. The testing program included compression strength test, four-point flexural test, direct tension test, single and double face shear tests. The experimental results show that the increasing time of exposure to wetting and drying cycles lead to a significant increase in compressive strength, increasing the cracking loads which reached up to 22%., and decreasing the ultimate load carrying capacity.

Behavior of Corbels Strengthened with Carbon Fiber Reinforced Polymers (CFRP) – Numerical Study

Sameh Badry Tobeia

Engineering and Technology Journal, 2014, Volume 32, Issue 10, Pages 2394-2407

In this paper, a numerical modeling performed to study the effect of carbon fiber reinforced polymers (CFRP) as a shear strengthening of corbels. In this study a theoretical simulation is achieved with reinforced concrete corbels, several CFRP strengthening positions has been studied with different shear span – effective depth ratio (a/d) of (0.5,0.6&0.7). The numerical model, by using program (ANSYS 12.1) verified by compare its results with the experimental results. It was found that the position and the amount of (CFRP) as well as the vary of (a/d) ratio, have a great effects on the ultimate load capacity of corbels. Where, the ultimate load capacity increase as the amount of (CFRP) increased in certain positions of corbels, with regards the vary in (a/d) ratio.

Experimental and Numerical Study of the Effects Of Creating Openings in Existing RC Beams and StrengtheningWith CFRP

Hayder Qais Majeed

Engineering and Technology Journal, 2012, Volume 30, Issue 15, Pages 2550-2561

This study presents an experimental and nonlinear finite element analysis of creating square openings in existing RC beams and strengthening with CFRP laminate. Flexural strengthening of reinforced concrete beams is now becoming more and more important in the field of structural maintenance and retrofitting. In the experimental programming, three RC beams were cast. Two beams were tested in the un-strengthened condition the first act as the solid Control beam, and the other have openings, the third one have opening and strengthening with CFRP laminate. The beams were also modeled using a FEM packaged (ANSYS 11). The results indicate that the strengthened beam recorded the highest failure load and its mode of failure was ductile. The numerical results seemed to be able to predict the behavior of the beams.