Q:- Calculate the cutting length of the stirrups given in fig 1. Clear cover of beam is 25 mm & Diameter of stirrup is 8 mm
Ans:-
Given data:
Clear cover = 25 mm
Depth of beam = 450 mm
Width of beam = 300 mm
Diameter of stirrup =8 mm
Cutting length of stirrup = 2a+2b + (2 x Hook length) – Bend deduction
Where,
a= Width of beam – (2 x clear cover) – ( 2 x Half of diameter of bar)
b= Depth of beam – (2 x clear cover) – ( 2 x Half of diameter of bar)
Therefore,
a= 300 – (2 x 25) – (2 x 4) = 242 mm
b= 450 – (2 x 25) – (2 x 4) = 392 mm
Length of hook (Development length) = 10 d = 10×8 = 80 mm
Bend deductions:
90 degree bent –> 3 no’s
For 90 degree bend, length reinforced bar increase by 2 d
i.e., Bend length = 3 x (2×8) = 3×16 = 48 mm
135 degree bent –> 2 no’s
For 135 degree bend, length reinforced bar increase by 3d
i.e., Bend length = 2 x (3×8) = 2 x 24 = 48 mm
∴ Cutting length of stirrup = (2×242) + (2×392) + (2×80) – (48+48) = 1428 – 96 = 1332 mm
