Quantity Calculation Of Round Staircase
This is a very useful article for Civil Engineering students. In this article, you will learn how to design and work out the quantity of semi round stairs.
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The calculation is done based on the following dimensions:-
Linear Length of Stair = ?
Inclined Length of Stair = ?
Waist of stair = 4.5 feet
Thickness of stair waist = 0.41 feet
Riser of stair = 6’’= 0.5 feet
Tread of stair = 1’’-3’’ -1’ (One side & opposite side)
No. of steps = Height / One Riser = 10 feet / 0.5 feet = 20 numbers
Now, it is required to determine the linear length as follow:-
2 (π x R) 0.50 = 2 (3.142 x 9.5) 0.50 = 29.84 feet
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Then it is required to determine the inclined length as follow:-
√(Base)2 + (Height)2
√(29.84)2 + (10)2
√(890.42) + (100) = √990.42 = 31.47 feet
So, inclined length = 31.47 feet
Then, you have to find out the waist volume by using the following formula:-
Waist Volume = Length x width x Thickness = 31.47 x 4.5 x 0.41 = 58.062 cft
Steps volume = ?
Width of tread = 1’- 3’’- 1’ = 1.25 + 1 = 2.25’/2 = 1.125’
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Now, it is required to determine one step volume with the following formula:-
One step volume = L x W x H / 2 or Length x Width x Height / 2 (as the steps are in triangular shape)
= 4.5 x 1.125 x 0.5 / 2 = 1.26 cft
So, the volume of one step = 1.26
As the numbers of steps are 20
So, total steps = 20 x 1.26 = 25.2 cft
Total Volume = Volume of waist + Volume of total steps
= 58.062 + 25.2 = 83.26 cft
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