**Clear Cover to Main Reinforcement**

Footings: 50 mm

Raft foundation Top: 50 mm

Raft foundation Bottom / sides: 75 mm

Strap Beam: 50 mm

Grade Slab: 20 mm

Column: 40 mm (d>12 mm) 25 mm (d= 12 mm)

Shear Wall: 25 mm

Beams: 25 mm

Slabs: 15 mm or not less than the diameter of the bar.

Flat Slab: 20 mm

Staircase: 15 mm

Retaining Wall on Earth: 20 / 25 mm

Water retaining structures: 20 / 30 mm

Sunshade: 25 mm

**Weight of Rod per Meter Length. Diameter Weight per Meter (D^2/162)**

8 mm = 0.395 Kg

10 mm = 0.616 Kg

12 mm = 0.888 Kg

16 mm = 1.578 Kg

20 mm = 2.466 Kg

25 mm = 3.853 Kg

32 mm = 6.313 Kg

40 mm = 9.865 Kg

**Concrete Grade:**

M5 = 1:5:10

M7.5=1:4:8

M10= 1:3:6

M15= 1:2:4

M20= 1:1.5:3

M25= 1:1:2

M30 and above grade based on design mix

**What is D2/162.27 in steel ?**

weight of steel bar per meter = Volume of steel x Density of steel

Weight of steel bar per meter = πD^{2}/4 x 1000 mm (for 1m lenght) x 7850 kg/ 1000 mm x 1000 mm x 1000 mm

Weight of steel bar per meter = 3.14D^{2}/4 x 7850/1000 x 1000 = 0.785D^{2} x 0.00785

Weight of steel bar per meter = 0.0061622 x D^{2 }= D^{2}/1/0.0061622 = D^{2}/162.27

**1 Cubic Meter Concretes 500 Bricks?**

So brick with motor=200 x 100 x 100.

Volume of 1st class brick = 0.19 x 0.09 X 0.09 = 0.001539 cu.m

Volume of 1st class brick with motor =0.2 x 0.1 x 0.1=0.002 cu.m

No. on bricks per 1cu.m= 1/volume of1st class brick with mortor ⇒ 1/0.002 ⇒ 500 No. of bricks

**Calculate Quantities of Materials for Concrete -Cement, Sand, Aggregates for Grade M20:Ratio is 1:1.5:3**

As we know that during concreting when we place wet concrete , it gets harden after certain standard time( 30 mins IST & 10hrs FST)

volume of dry Concrete = 1.54 to 1.57 times Volume of wet concrete.

sand requried=1.5/5.5*1.57=0.471m3

aggregate required=3/5.5*1.57=0.853m3

**Unit Weight of Materials Used at Construction Site:**

1- Water= 1000 Kg/ m3

2- Bricks (broken)= 1420 Kg/ m3

3- Bricks(common)= 1600 Kg/ m3

4- Cement(ordinary)= 1440 Kg/ m3

5- Cement (rapid hardening)= 1250 Kg/ m3

6-Cement Mortar= 2000 Kg/ m3

7- Cement Concrete (Plain)= 2400 Kg/ m3

8- Cement Concrete (Reinforced)= 2500 Kg/ m3

9- Glass= 2500 Kg/ m3

10- Lime Concrete= 1900 Kg/ m3

11- Cement Plaster= 2000 Kg/ m3

12- Lime Plaster= 1700 Kg/ m3

13 Stones (Ballast)= 1720 Kg/ m3

14- Stones (Aggregates)= 1750 Kg/ m3

15- Stones (Basalt)= 2850 Kg/ m3

16- Stones (Granite)= 2450 Kg/ m3

17- Stones (Marble)= 2650 Kg/ m3

18- Timber (Oak, Sal)= 510 Kg/ m3

19- Timber (Mango)= 650 Kg/ m3

20- Timber (Teak)= 625 Kg/ m3

21- Coal 600= Kg/ m3

22- Plastics= 1250 Kg/ m3

23- Oils= 800 Kg/ m3

24- Ashes= 650 Kg/ m3

25- Clinker= 750 Kg/ m3

26- Rubber= 1300 Kg/ m3

27- Slag= 1500 Kg/ m3

28- Clay Soil= 1900 Kg/ m3

29- Sand (dry)= 1540 to 1600 Kg/ m3

30- Sand (wet)= 11760 to 2000 Kg/ m3

31- Steel= 7850 Kg/ m3

32- Chalk= 2100 Kg/ m3

33- Bitumen= 1040 Kg/ m3

**De-Shuttering time of different RCC Members:**

For columns, walls, vertical form works: 16-24 hrs

Soffit formwork to slabs: 3 days (props to be refixed after removal)

Soffit to beams props: 7 days (props to refixed after removal)

Beams spanning upto 4.5m: 7 days

Beams spanning over 4.5m: 14 days

Arches spanning up to 6m: 14 days

Arches spanning over 6m: 21 days

**Design Mix:**

Cement : 210 Kg/ M 3

20 mm Jelly : 708 Kg/ M 3

12.5 mm Jelly : 472 Kg/ M 3

River sand : 823 Kg/ M 3

Total water : 185 Kg/ M 3

Fresh concrete density: 2398 Kg/M 3

Cement : 320 Kg/ M 3

20 mm Jelly : 683 Kg/ M 3

12.5 mm Jelly : 455 Kg/ M 3

River sand : 794 Kg/ M 3

Total water : 176 Kg/ M 3

Admixture : 0.7%

Fresh concrete density: 2430 Kg/ M 3

Cement : 340 Kg/ M 3

20 mm Jelly : 667 Kg/ M 3

12.5 mm Jelly : 445 Kg/ M 3

River sand : 775 Kg/ M 3

Total water : 185 Kg/ M 3

Admixture : 0.6%

Fresh concrete density: 2414 Kg/ M 3

Note: sand 775 + 2% moisture, Water185 -20.5 =

164 Liters,

Admixture = 0.5% is 100ml

Cement : 380 Kg/ M 3

20 mm Jelly : 654 Kg/ M 3

12.5 mm Jelly : 436 Kg/ M 3

River sand : 760 Kg/ M 3

Total water : 187 Kg/ M 3

Admixture : 0.7%

Fresh concrete density: 2420 Kg/ M 3

Note: Sand = 760 Kg with 2% moisture

(170.80+15.20)

Cement : 410 Kg/ M 3

20 mm Jelly : 632 Kg/ M 3

12.5 mm Jelly : 421 Kg/ M 3

River sand : 735 Kg/ M 3

Total water : 200 Kg/ M 3

Admixture : 0.7%

Fresh concrete density: 2400 Kg/ M 3

Note: sand = 735 + 2%, Water = 200- 14.7 =

185.30,

Admixture = 0.7%

Cement : 430 Kg/ M 3

20 mm Jelly : 618 Kg/ M 3

12.5 mm Jelly : 412 Kg/ M 3

River sand : 718 Kg/ M 3

Water Cement ratio : 0.43

Admixture : 0.7%

Note: Sand = 718 + Bulk age 1%

Cement : 450 Kg/ M 3

20 mm Jelly : 626 Kg/ M 3

12.5 mm Jelly : 417 Kg/ M 3

River sand : 727 Kg/ M 3 + Bulk age 1%

Water Cement ratio : 0.43

Admixture : 0.7%

Cement : 450 Kg/ M 3

20 mm Jelly : 590 Kg/ M 3

12.5 mm Jelly : 483 Kg/ M 3

River sand : 689 Kg/ M 3 + Bulk age 12%

Water Cement ratio : 0.36 (188 Kg)

Admixture : 1.20%3

Micro silica : 30 Kg

Super flow 6.7% of cement

**Standard Conversion Factors:**

###### Length

1 kilometer (km) = 1000 meters (m)

1 meter (m) = 100 centimeter (cm)

1 centimeter (cm) = 10^{-2}m

1 millimeter (mm) = 10^{-3}m

1 micron (μ) = 10^{-6}m

1 millimicron (mμ) = 10^{-9}m

1 angstrom (A) = 10^{-10}m

1 inch (in.) = 2.54 cm

1 foot (ft) = 30.48 cm

1 mile (mi) = 1.609 km

1 mil = 10^{-3} in.

1 centimeter = 0.3937 in.

1 meter = 39.37 in.

1 kilometer = 0.6214 mile

**Area**

1 square meter (m^{2}) = 10.76 ft^{2}

1 square mile (mi^{2}) = 640 acres

1 square foot (ft^{2}) = 929 cm^{2}

1 acre = 43,560 ft^{2}

**Volume**

1 liter (l) = 1000cm^{3} = 1.057 quart (qt) = 61.02 in^{3} = 0.03532 ft^{3}

1 cubic meter (m^{3}) = 1000 l = 35.32 ft^{3}

1 cubic foot (ft^{3}) = 7.481 U.S.gal = 0.02832 m^{3} = 28.32 l

1 U.S. gallon (gal) = 231 in^{3} = 3.785 l

1 British gallon = 1.201 U.S.gallon = 277.4 in^{3}

**Mass**

1 kilogram (kg) = 2.2046 pounds (lb) = 0.06852 slug;

1 lb = 453.6 gm = 0.03108 slug

1 slug = 32.174 lb = 14.59 kg

**Curing Days Required:**

Super Sulphate cement : 7 days

Ordinary Portland cement OPC : 10 days

Minerals and Admixture added cement : 14 days