EXPERIMENTAL STUDY OF SELF-COMPACTING REINFORCED CONTINUOUS DEEP BEAMS

الملخص

Test results of twelve reinforced self-compacted concrete two-span deep beams casted by using self-compacting concrete are reported. The main variables studied were shear span-to-overall depth ratio (a/h), concrete strength (fʹc) and the amount of vertical shear reinforcement ratio (ρv). All specimens had the same dimensions and main flexural reinforcement. Tests pointed out that all beams failed in shear with diagonal splitting mode. It was found that shear span to overall depth ratio (a/h) effects the load carrying capacity of beams such that a decrease of 50 % in that ratio from 1 to 0.5, the cracking load (Pcr) and ultimate load (Pult) increase by average ratios of 29% and 25% respectively. The concrete compressive strength (fʹc) are also had a noticeable influence on the continuous deep beams behavior such that increasing (fʹc) to almost twice from (33.81 to 67.8) MPa led to an increase in the cracking load (P_cr) and ultimate load (P_ult) by average ratios of 12.75% and 16.5% respectively. When (ρ_v) is increased by 80% from (0.25% to 0.45%) a better increase shear capacity of both NSCC & HSCC deep beam having (a/h) ratio of 1.0 (enhancement reached to18.56% and 23.1% respectively) as compared to the reference beams without shear reinforcement (ρv=0).