BEHAVIOUR AND STRENGTH OF SUSTAINABLE RUBBERIZED REINFORCED CONCRETE BEAMS STRENGTHENED BY CFRP

Abstract

The current study is interested for investigating the effect of replacing 50% of sand by textured rubber (Crumb Rubber) that reduced 10% from specimen's weight, then using the CFRP to strengthening the flexural efficiency of beams. Five specimens with 200x300x2000mm dimensions are investigated. The variables are studied in instillation of CFRP. Three situation of fixing the CFRP, the first is in area exposed to flatten, the second in both regions of tension and compression and the last one covered all faces by CFRP. Laboratory results showed that when replacing 50% of sand by crumb rubber the weight of beams decreased by 9% and increased the ductility by 74% also the crack width is reduced by 9% and 38% at yield and ultimate loads respectively. Strengthening by CFRP strips is increase the yield and ultimate load by 40% and 35% on average respectively, but by covering all faces the ratios was increased by 60% and 63%. Using the crumb rubber decreased the deflection by 27% on average and by using CFRP the defection was decreased by 36%, 19% on average at yield and ultimate load respectively. CFRP is increase the strain in compression face of concrete and the value was greater than maximum strain of concrete (0.003). Also the crack width was decreased by 45% , 23% on average at yield and ultimate loads respectively.