In modern buildings, transverse openings are often used beams for the purpose of supplying and service pipes. Due to the presence of the openings in the concrete beams lead to the formation of cracks around the openings due to the stresses concentration in a small area above and below of the opening. The repairing, maintenance, and upgrading of structural members, are maybe one of the most pivotal problems in civil engineering applications. In this research, an experimental work is conducted to study the behavior of the reinforced RPC T-beams that containing openings and repair this beams using CFRP strips. The Experimental program of the present study includes two parts, the first part includes testing of seven reinforced reactive powder concrete RPC T-beams, which casted and tested, one beam is without opening as a reference beam and the rest, were provided with an opening. and these beams are divided into two groups. The first group was used to study the effect of the openings shape (circular and square) and the second group was used to study the effect of the openings locations, which consists three locations (Lc/2, Lc/3 and Lc/4).These are measured from the support center to the openings center. While the second part including a repaired all beams in the first part the using carbon fiber polymer. The test results indicated that the presence of openings in the beams web caused a reduction in the reinforced RPC T-beams ultimate load carrying capacity with about (10-55)%, Also lead to increasing in deflection compared to control beam before repairing at same loading. Studying the shape effect showed that the beams with square openings have average ultimate load carrying capacity lower by 36% compared with the control beams.While beams with containing circular openings have average ultimate load carrying capacity lower 29%. From the test results, it could be concluded that the presence of the openings in the shear region led to a decrease in ultimate load carrying capacity a about 38% to 49% for opening of opening at (Lc/3 and Lc/4) respectively. While the presence of openings in the flexural region led to a decrease in the ultimate load carrying capacity rate of 11%. Related to the repairing study part it was found that the average ultimate load carrying capacity for repairing beams was 103% compared with the not repaired beams.
In this research, the response of reactive powder concrete T-beams containing openings is studied. The experimental program involves testing of thirteen simply supported beams. The beams have the same dimensions, flexural and shear reinforcements. In this study, four three parameters have been studied: the shape of an opening (circular and square), a location of openings from the support (Lc/2, Lc/3, and Lc/4), and the internally strengthened around of opening using a deformed steel bar. The experimental results showed that the RPC T-beams with circular openings of diameter (110mm) with different locations (Lc/2, Lc/3 and Lc/4) have a flexural strength less than that solid beam by about (12%,35%and 41%) respectively. While for the RPC T-beams with square openings of dimension (100mm×100mm) with different locations (Lc/2, Lc/3, and Lc/4), the flexural strength is less than that solid beams by (10%,41%and 55%) respectively. In addition, it is found that the use of deformed steel bars as internal strengthening for the region around the openings has a significant effect on the overall behavior of beam. Where the ultimate flexural strength of these strengthened beams containing (circular and square) openings with different location increased by (9% to 66%) in comparison with the related un-strengthened beams with same openings. Also, this T-beams with openings showed increasing in deflection about (66.7% - 202%) compared with T-beam without openings at the same load. While for these strengthened T-beams with openings showed a reduction in deflection about (50% - 192%) compared with un-strengthened T-beam with openings.
The experimental study investigates the effect of using recycled demolition aggregate (RDA) on the flexural behaviour of reinforced concrete beams. The beams were 1400 mm long, 150 mm wide and 200 mm deep, with the same longitudinal and shear reinforcement. The replacement ratios of recycled demolition aggregate are 0 %, 25 %, 50 %, 75 %, and 100 % of the coarse aggregate weight. The results presented that the deflections of the beams were reduced by up to 15 % and 43 % of 75 % RDA and 100% RDA, respectively when compared to the control beam. Furthermore, at 100% RDA, ductility, stiffness, and toughness were reduced by approximately 24 %, 10 %, and 34 %, respectively. At the same stage of loading, RDA beams cracked faster than normal aggregate beams.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.