SEMI‐ROUND STAIR‐CASE CALCULATION | QUANTITY SURVEY | VOLUME OF CONCRETE & AREA OF SHUTTERING -lceted LCETED INSTITUTE FOR CIVIL ENGINEERS

## Nov 17, 2021

SEMI‐ROUND STAIR‐CASE CALCULATION | QUANTITY SURVEY | VOLUME OF CONCRETE & AREA OF SHUTTERING

For a given drawing of a Semi‐round Stair‐case find

1. Volume of Concrete

2. Area of Shuttering

Height of riser = 0.15m

Radius of waist Slab = 3.50m

Height of Ceiling = Height of Riser x No. of Riser

= 0.15 x 24

= 3.60m

Waist Slab thickness = 0.15m

Width of Waist Slab = 1.30m

no. of Step = 24

(A) Solution for staircase:

To find out Semi‐Circle Length the formula = 2 x π x r x 0.50 Therefore,

Radius of waist slab 'r'= 3.50m

= 2 x π x 3.5 x 0.50

= 10.99m (linear length)

Inclined length = √(10.992 + 3.602)

C = 11.56m

1. Waist Slab:

(a) Volume of Concrete for waist slab = Area x thickness

= L x B x D

= 11.56 x 1.30 x 0.15

= 2.254 m3

(b) Shuttering Area for waist slab = L x D x 2 + B x D + L x B

= 11.56 x 0.15 x 2 + 1.30 x 0.15 + 11.56 x 1.30

= 18.691 m2

2. Steps:

Length of step = 1.30m

Width of tread = 0.30m on one side and 0.40m on other side Average width of riser = (0.30 + 0.40)/2

B = 0.35m

Height of Riser = 0.15m

(a) Volume of Concrete for Step = Area x length of step x no. of steps

= 1/2 x b x h x L x no. of steps

= 0.50 x 0.35 x 0.15 x 1.3 x 24

= 0.819 m3

(b) Shuttering area for Step = (1/2 x B x H x 2 + L x D) x no.s

= (0.50 x 0.35 x 0.15 x 2 + 1.30 x 0.15) x 24

= 5.94 m2

3. Hand‐Rail :

Therefore,

L = 11.56m

B = 0.10m D = 0.80m

no.s = 2

(a) Volume of Concrete for Hand‐Rail = area x depth x no. of Hand rails

= L x B x D x no.s

= 11.56 x 0.10 x x 0.80 x 2

= 1.849 m3

(b) Shuttering area for Hand‐Rail = (L+B) x 2 x D x no.s

= (11.56 + 0.10) x 2 x 0.80 x 2

= 37.312 m2

(i) Total Concrete for stair case = 2.254 + 0.819 + 1.849

= 4.922 m3

(ii) Total Shuttering area for stair‐case = 18.691 + 5.94 + 37.312

= 61.943 m2

If you find