r = 450 – 40 – 4

r = 406 mm


cutting length of circular stirrups

= 2πr + ( 2 x 10 x d ) – ( 2 x 2d )

= ( 2 x 3.14 x 406 ) + ( 2 x 10 x 8 ) – ( 2 x 2 x 8 )

= 2677.68 mm

= 2.68 meter