The beam is subjected to a maximum factored shear force of $400$ KN. The materials are the concrete of grade M20 and TOR steel. Refer table for the values of allowable shear stress(Zc)

$$b = 350 mm $$ $ d = 500 mm \\ V_{UD} = 500 KN \\ F_ck=20N/mm^2\\ f_y=415 N/mm^2\\ Ast=4-25 mm \phi=1964mm^2\\ Z_uv=\dfrac {V_{UD}}{b\times d}=\dfrac {400 \times 10^3}{350\times 500}=2.28 N/mm^2 \lt 2.8 N/mm^2\\ pt=\dfrac {100\times Ast}{b\times d}=\dfrac {100\times 1964}{350\times 500}=1.12\%$

shear stress in concrete (Zuc):-

By interpolation

$$\dfrac {0.67-0.62}{1.25-1}=\dfrac {(Zuc-0.62)}{1.12-1}$$ …