STEEL FIBER REINFORCED CONCRETE HAUNCHED BEAMS

Abstract

 Abstract

There is an architectural, structural and economic importance of the study of the reinforced concrete haunched beams (RCHBs). In this study, mechanical behavior of steel fiber reinforced concrete haunched beams was investigated. The study included 8 self-compacted concrete beams (7 of which are RCHBs and one of which are prismatic beams), Two different ratios of steel reinforcement were considered. The stirrup reinforcement was used for half specimens. Three steel fiber ratios (0%, 0.5% and 1%) were adopted. Two angle of inclination which are 10^o & 15^o, were considered for the study. The results showed that load capacity of the beams was inversely proportional to the increase in the angle of inclination and was proportional to the increase in the ratio of the steel fiber. Effect of steel fiber was much more apparent, as the inclination angle of the haunched beams increased. Moreover, use of steel fiber reduced the crack width of all beams at failure leading to increase in the service life of the beams. the addition of fibers with sufficient ratio changed the failure mode of RC haunched beams without stirrups from shear to flexure mode. Therefore, the steel fibers can be considered as a suitable solution to replace the stirrups in the reinforced concrete haunched beams. 

Keywords

• Steel fiber,self-compacting concrete,Haunched beams,shear stress

References

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