How to Calculate Quantity of Concrete Volume of Staircase
Various Parts Of the Staircase A staircase comprises of two parts – Step and Landing. Step: A step stands for a triangular-shaped segment of a staircase that stands on an inclined slab (Waist slab). There are two sections in a step i.e. Riser and Tread. Riser: Riser refers to the vertical section of steps. Generally, the height of a riser remains six inches. Tread: It belongs to the horizontal section of a step. The width of a tread is generally remains ten inches. Landing: It refers to the horizontal slab provided in among the flights of a staircase. The purpose of landing is to adjust the moving direction of a stair. Flight: Generally, a staircase contains two flights. One is located under the landing and another is over the landing. The flight under the landing is known as first flight and the flight over the landing is known 2nd flight. Given below, the detail process for working out the concrete quantity of any staircase :To find out the concrete quantity of a staircase, it is required to measure the concrete volume for the followings :-
• • •
Steps and waist slab of 1st flight Steps and waist slab of 2nd flight, and Landing.
Concrete volume for 1st flight of the staircase The calculation is done on the basis of the following data :Riser = 6 inches Tread = 10 inches Length of a step = 4 feet Number of steps = 9 The thickness of the waist slab = 6 inches
Concrete volume for the waist slab To find out the concrete volume for the waist slab, you have to find out the inclined length of the waist slab. Inclined length of waist slab can be measured from the architectural plan. The horizontal length of a waist slab is, =number of steps x tread = 9 x 10” = 7′-6”. The height of the landing top from floor should be calculated as follow := number of riser x height of riser = 10 x 6″ [number of riser = number of steps = 1] = 5 feet. Therefore, the inclined length of the waist slab is, =√{(horizontal length)2 + (Height)2} = (7’-6”)2 + (5’)2
= 9’ (round up) Therefore, the concrete volume for the waist slab is, = inclined length of waist slab x width of waist slab (width of a step) x thickness of waist slab = 9’ x 4’ x 6” = 18 cubic feet Concrete volume for steps Since the steps come in triangular shape, the volume of a step should be calculated as follow := ½ x tread x riser x length of a step = ½ x 10” x 6” x 4 = 0.84 cubic feet As there are 9 numbers of steps in a flight, the concrete volume for the steps of the first flight should be as follow := 9 x 0.84 = 7.56 cubic feet Therefore, the total concrete volume for the 1st flight of the staircase should be :-
= Waist slab concrete + steps concrete = 18 + 7.56 = 25.56 cubic feet
Concrete volume for 2nd flight of the staircase Suppose, 1st flight and 2nd flight are identical, therefore the concrete volume is also same i.e. 25.56 cubic feet Now, determine the concrete volume for landing.
Concrete volume for the stair landing is measured based on the following data Length of landing = 8’-6” Width of landing = 4’-6” The thickness of landing = 6” Therefore, the concrete volume for the landing should be as follow := 8’-6” x 4’-6” x 6” = 19.12 cubic feet Therefore, the total concrete volume for the staircase is,
= 1st flight concrete + 2nd flight concrete + landing concrete = 25.56 + 25.56 + 19.12 = 70.24 cubic feet ~~~~~~~~~~~~~~~~~ Visit our facebook page to get some vital information on civil engineering field. https://www.facebook.com/sketchup3dconstruction/