The cutting length of the triangular stirrup is done by using simple and easy formula.
Let’s solve this example for your better understanding.
Example
Suppose we are using a triangular stirrup in a column and a column having a Length 500 mm and having a Width 500 mm (X-section). The clear cover in the column will be 40 mm and the stirrup bar is going to use is 10 mm.
1- Calculate the cutting length of the triangular stirrup?
2- Also, calculate its weight?
Given data
Length of column = 500mm.
Width of column = 500 mm.
Clear cover = 40 mm.
Stirrup bar diameter = 10 mm.
length of the stirrup =?
The weight of the stirrup =?
Solution
The calculation of the triangular stirrup is to be done in 2 steps. In the first step, we calculate the Hypotenuse length of the right angle by using Pythagoras theorem. In the second step, we put these values into our given problem.
First A is the horizontal x section area and B is vertical x sectional area.
First we find A
= 500 – (2 x clear cover) – (2 x half of dia of bar)
= 500 – (2 x 40) – (2 x 5)
= 500 – 80 – 10
= 410mm
= (500 – (2 x 40) – (2 x 5))/2
= (500 – 80 – 10)/2
= (410mm)/2
= 205 mm Ans…
Then we find the hypotenuse of the triangle
H=√(base)2+(Perpendicular)2
H=√A2+B2
H=√4102+2052
H = 458.39 mm
Cutting Length
= (2 x H) + 2B + hook – bend
= (2 x H) + 2B + (2 x 10d) – (we have got 4 bends of 135 deg so minus 3d)
(Where d is dia of used in stirrups)
= (2 x H) + 2B + (2 x 10d) – (4 x 3d)
= (2 x 458.39) + 410 + (2 x 10 x 10) – (4 x 3 x 10)
= 916.78 + 410 + 200 – 120
= 1406.7mm or 1.406m
Weight of this stirrup
= d2/162 x length
= 102/162 x 1.406
= 0.867kg Ans