**Concrete quantity calculation for staircase** and find out volume of waist slab and number of Riser and number of tread and what is incline length horizontal length and flight height and landing.

**●staircase**:- staircase is used in building for walking from ground floor to upper floor. Staircase have many component like riser tread flight landing etc.

**●tread**:- tread is defined as horizontal part of staircase on which we first apply foot on this for walking from ground floor to upper floor.

**●Riser**:- vertical part of staircase

**●Step**:- the series of Riser and tread in which tread is horizontal part and riser is vertical part.

**●flight**:- series of step without any platform generally in building there is a two flight and one landing . When we reach up to landing we turn and reach up to the upper floor.

### ● **what is admixture of concrete and its properties and types**

**●waist slab:**– inclined length of staircase

### (**1Q) concrete quantity calculation for staircase:-**

### it compromise of following calculation:-

### 1) **volume of all step:** in staircase first we calculate volume of all step

### ● **given dimension:-**

Height of building= 10 feet

if each flight have equal height

Height of landing =10/2’=5′

Height of one flight=5′

Riser = 6″ =6″/12= 0.5 feet

Tread =10″ =10″/12=0.833′

### No.of riser= height of flight/ 1 riser height

Number of riser= 5’/0.5 =10

### Number of tread =(riser-1)=10-1=9

Note that number of tread is equal to number of step so we have

Number of step=9

One step length is=4 feet

### Volume of all step in one flight

=1/2×riser×tread× length of step×no. of step

=1/2×0.5″×0.833×4×9=7.497 cft

### Volume of step in 1 flight =7.497 cft

**(2) volume of Waist slab**:-

for the calculation of volume of Waist slab first we should find horizontal length of Waist slab and inclined length of Waist slab

### Horizontal length=tread×no. of step

Horizontal length =0.833×9=7.497′

### Now inclined length of waist slab

= √(5*2+7.497*2) under root of square of both

Inclined length of waist slab=9.012 feet

### Volume of waist slab = incline length of Waist slab ×length of step ×thickness of Waist slab

### Thickness of slab = 6″=6″/12=0.5′

### Volume =9.012’×4’×0.5’= 18.024 cft

Volume of waist slab=18.024 cft

### (3) **volume of one flight:-**

volume of one flight is equal to sum of volume of all step in one flight and volume of waist slab

### Volume of one flight=v of step+v of waist slab

Volume of one flight=7.497+18.024

Volume of one flight=25.521 cft

### Volume of two flight =25.521×2 =51.042 cft

### (4) **volume of landing:-**

for the calculation of volume of landing we have given dimension for landing:-

### Length =8.5feet,

Thickness= 6″=0.5′

Breadth = 4 feet

### Volume of landing =L×B×T

Volume of landing =8.5’×4’×0.5’=17cft

### (5) **now we have to calculate total volume of concrete in staircase :-**

total volume of concrete in staircase is sum of volume of two flight and volume of one landing

### Total volume= volume of two flight +volume of one landing

### Total volume=51.042 +17 = 68.042 cft

### Hence total concrete volume in staircase is approx 68.042 cft

### (6) **now we have to calculate wet volume and dry volume of concrete:-**

### Total concrete volume in staircase is wet volume

Wet volume = 68.042 cft

### Dry volume is increased by 54% in concrete reinforcement so we multiply cofactor 1.54 in wet volume to calculate dry volume

### Dry volume =68.042×1.54=104.78 cft

### (7) **mix ratio**:- mix ratio of concrete reinforcement in staircase is 1:1.5:3 in which one part is cement 1.5 part is sand and 3 part is aggregate

### Total ratio =1+1.5+3=5.5

### (8) **quantity calculation of cement:-**

in mix ratio of concrete volume cement is one part and total ratio is 5.5

### Volume of cement=1/5.5×dry volume

Volume of cement=1/5.5×104.78 cft

Volume of cement =19.05 cft

### We know that

Volume of 1 bag cement =1.226 cft

### No. Of bag of cement =19.05/1.226

Number of bag of cement= 15.538 bags

### (9) **sand quantity :-**

in mix ratio quantity of sand is 1.5 and total ratio is 5.5

Volume of sand= 1.5/5.5×104.78

Volume of sand=28.57 cft

**(10) calculation of aggregate quantity :-**

in mix ratio quantity of aggregate is 3 part and total ratio is 5.5

### Volume of aggregate=3/5.5×104.78

Volume of aggregate=57.15 cft

### (11) **quantity of steel** calculation:- approx 0.5 % to 0.1 percent Steel reinforcement used in slab we have taken about 0.75 percent of Steel reinforcement of dry volume of concrete

Density of steel=7850kg/m3

1m3 =35.315cft

W of steel = volume×density

### Steel quantity

=(0.75×104.78×7850)÷(100×35.315)

### Weight of Steel=174.68 kg

### ● **result:-**

**1) concrete wet volume =68.042 cft**

**2) concrete dry volume=104.78cft**

**3) cement quantity=15.538 no. of bags**

**4) sand quantity= 28.57 cft**

**5) aggregate quantity=57.15cft**

**6) Steel quantity =174.68 kg**