Spiral bars are frequently applied in round columns, piers and piles.
Therefore, it is necessary to know the process efficiently for defining the cutting length of a spiral bar or helix bars as well as measuring the quantities.
Spiral bars are generally utilized in round columns as they perform in a superior manner as compared to tie bars.
The dimension of the spiral bars is as follow :-
Height = 15’
Top Diameter = 4’
Bottom Diameter = 4’
Pitch (in perpendicular distance) = 3’
To determine the length of helix/spiral bar, the following formula is used :- 
Here, n denotes number of turns
C denotes circumference of spiral
P denotes Pitch
On the basis of the above figure, the calculation is made for finding out the cutting length of a spiral bar.
Watch the following video to learn the complete process.
Video Source: SL Khan
