STRENGTH OF REINFORCED CONCRETE CORBELS – A PARAMETRIC STUDY

Corbels are cantilever with small shear span to depth ratio (a/d) projected from columns or walls to support precast members like beams, girders or dapped end beams. Shear friction (SF) method is used to analyze and design reinforced concrete (RC) corbels. Because of the small value of a/d, corbels are treated as deep beams. Using strut and tie modeling (STM), they can be analyzed. In both SF and STM, there are many parameters that affect the behavior of the corbels such as a/d, width (b), compressive strength of concrete (f'c), yield strength of reinforcement (fy), and horizontal to vertical load ratio (H/V). In the current study, according to ACI 318-14 provisions, the effect of these parameters were investigated using both SF and STM. It was found that the shear capacity increases by about 32.6%, 26.3% and 31.2% for SF and by about 54.1%, 50.4% and 30.9% for STM with increasing width, compressive strength, and yield strength by about (100-300) %, (15-35) % and (400-600) %, respectively. Whereas, shear capacity decreases by about 58.54% and 48.7% for SF and about 59.4% and 33.2% for STM with increasing a/d and H/V by about (0.1-1.9)% and (0-1)%, respectively. It was also seen that the results obtained by STM is more reliable than SF when compared with experimental works that were taken from literature.