There may be a formula for calculating the length of spiral reinforcement in pile foundation? For example, the length of spiral reinforcement is Φ 10@12 The diameter of reinforcement cage is 108.4

There may be a formula for calculating the length of spiral reinforcement in pile foundation? For example, the length of spiral reinforcement is Φ 10@12 The diameter of reinforcement cage is 108.4

1. Calculation method of spiral stirrup: in cylindrical members (such as graphic column, pipe column, cast-in-place pile, etc.), spiral stirrup is wound along the circumferential surface of main reinforcement, and the length of spiral stirrup per meter of reinforcement skeleton length can be calculated according to the following formula:
l=2000лa/p×[1-e^2/4-3/64(e^2)^2 –5/256(e^2)^3]
Where a = √ (P ^ 2 + 4D ^ 2) / 4
e2=(4a^2-D^2)/( 4a^2)
Where, l-the length of spiral stirrup per 1m reinforcement framework length (mm);
P -- pitch (mm);
Γ - pi, taken as 3.1416;
D - winding diameter of helix; the center distance of stirrup, that is, the outer skin distance of main reinforcement plus a stirrup diameter (mm)
The value of the last item 5 / 256 (e ^ 2) ^ 3 in brackets is very small, which is generally omitted in calculation
2. Simple calculation method of spiral stirrup
In method 1, the length of spiral stirrup can also be calculated according to the following simplified formula:
l=1000/p×√（лD）^2+p^2+лd/2
Where D -- diameter of spiral stirrup;
Other symbols have the same meaning as before
Method 2: for members with less strict requirements for stirrup spacing, or when the ratio of P to D is small (P / d < 0.5), the stirrup length can also be calculated according to the following approximate formula:
l=n√p^2+（лD）^2
Where n is the number of spirals;
The meaning of other symbols is the same as before

What is the relationship between the length of spiral stirrup and pile diameter?

The calculation formula of spiral hoop is as follows
Length of spiral stirrup:
L = (length of densified zone / spacing of densified zone + 1) × sqrt (π× (diameter of member protective layer × 2 + diameter of stirrup) 2 + spacing of densified zone 2) + (length of non densified zone / spacing of non densified zone + 1) × sqrt (π× (diameter of member protective layer × 2 + diameter of stirrup) 2 + spacing of non densified zone 2) + 3 × π× (diameter of member protective layer × 2 + diameter of stirrup) + 12.5 × diameter of stirrup
Sqrt is root = square root
n: Number of turns of spiral hoop
p: Stirrup spacing
d: The lap length is added to the circle diameter
Turns = length / spacing

May I ask you the formula for calculating the length of spiral stirrups

The formula for calculating the length of equidistant spiral reinforcement is as follows:
L²= (πd)²+h²
Where: l is the length of single helix, D is the diameter of helix, h is the pitch