How to find out the quantity of steel in a triangular shape

Get some useful tips required to work out the quantity of steel bar in a triangular shape in kg or meter.

The calculation is done based on the following data.

The length of the triangular shape is taken as 4 meter and the height is taken as 2 meter. Inside the triangle, the steel bars will be placed as horizontally and vertically.

The diameter of the steel bars is 30 mm @500 c/c in both directions.

The calculation is done by applying two methods like with angle or without angle. Here, the length and height of the each bar will be reduced successively.

The following formula will be used to determine the angle of the shape :-

tan ? = Opposite / Adjacent = 2/ 4 or ? = tan-1 = 2/4 = 26.526 degree

Now, it is required to find out the length of the bar in horizontal direction. Now draw line maintain 90 degree angle. Thus, a small triangle will be formed.

The height of the small triangle = 500 mm = 0.5 meter. Here, the value of length is unknown. The value will be calculated with the following formula :-

tan ? = tan (26.565) = opposite / adjacent = 0.5 / x

x = 0.5 / tan (26.565) = 1 meter
So, the length of the small triangle = 1 m
Now, deduct this length from the length of the other steel bars successively.
Suppose, the length of the first steel bar = L1
The length of the second steel bar = L2
The length of the third steel bar = L3
So, L1 = 4 ? 1 = 3m
L2 = 3 -1 = 2m
L3 = 1 m.

By summing up, the total length will be 6 meter.
find out the angle in vertical direction, deduct the angle (detected earlier) from 90 degree
, ? = 90 ? 26.565 = 63.435 degree
Repeat the above process to find out the length of the steel bar in vertical direction.

For more details, go through the following video tutorial.

Video Source: ENGINEERING TACTICS