Effecting shear span ratio on high strength fiber reinforced concrete deep beams with circle openings

Abstract EN

Through this paper the effecting a/d on high strength fiber reinforced concrete deep beams with circle openings without stirrups have been studied to report behavior of deep beam by chang shear span ratio a/d for high strength deep beam with circle opening (12.6 cm) diameter at the center of shear span in term of crack pattern and load-deflection curve and stress-strain curve, this paper aim to investigate which specimen has better a/d, this study done by tested four specimens; first specimen is control deep beam without opening and steel fiber while the other are with steel fiber ratio (1%) and circle opening has diameter (12.6 cm) at the center of shear span and reinforced by (2Ø12mm) at the top and (3Ø16mm) at the bottom and two stirrups at the supports to prevent local failure, specimens with circle opening have various a/d (0.75,1,1.5) and total lengths (1025,1200,1550)mm, all specimens are simply supported with two points applied load, finally, the results present the perfect shear span ratio (a/d) with steel fiber (1%) is (0.75), The strength of specimens with circle opening decrease with increase shear span ratio (a/d) where strength rising into (5.48 %) at (a/d = 0.75) over than strength at (a/d = 1).

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INTRODUCTION