How to Calculate Cutting Length of Circular Ties (Links) in Columns
Calculating the cutting length of rectangular column ties (also known as stirrups or lateral ties) is important in reinforcement estimation. These are placed around the main vertical bars to keep them in place and to protect the column from bending or breaking.
This following article will show you how to do it step by step with an example
From on the image
Size of Column = 300 x 230 mm
Concrete cover = 25 mm (each side) – Clear cover to reinforcement
Diameter of Ties / Stirrups (d) = 8 mm – Size of the tie bar
Hook length = 9d
Standard Bend Loss For Reinforcement
For 45° bend = 1 x d
For 90° bend = 2 x d
For 135° Bend = 3 x d
For 180° bend = 4 x d
Formula For Cutting Length
Cutting Length = Total length of Ties / Stirrups + Hook Length – Bend Length
Calculate Length & Width of Ties / Stirrups
Length (L) = 300 mm – 2 × 25 mm = 250 mm → 0.275 m
Breadth (B) = 230 mm – 2 × 25 mm = 180 mm → 0.205 m
Calculate the total length (perimeter) of Stirrups
Perimeter = 2 × (Length + Breadth) = 2 × (250 + 180) 860 mm → 0.86 m
Calculate the Hook Length
Hook length = 9d (d= 8 mm)
so, 9 x 8 = 72 mm
Total 2 hooks per tie. so, 72 x 2 = 144 mm → 0.144 m
Calculate the Bend Loss
Circular ties typically have two 90° bends, each with a length of 2d.
Bend Length = 2d = 2 x 8 =16 mm
Total 4 bends = 4 *16= 64 mm → 0.064m
So Cutting Length
Cutting Length = Total length of Ties / Stirrups + Hook Length – Bend Length
Cutting Length for rectangular Ties or Stirrups = 860 + 144 – 64 = 940 mm → 0.94 m
