General Important conversion a Civil Engineer should know

As we all know that basic of Civil Engineering is all related to measurement and calculations.
In this article I will discuss some useful formation and formulas which are related with field and it must be kept in minds by every Civil Engineer..

Below are the generally used data which a civil engineer is expected to memorise it .This would be important for interview perspective as well as at the site..

1. Unit Weight Of Steel in Kg Per Meter For Different Diameter:

For 6 mm steel the weight is 0.222 kg/m
For 8 mm steel the weight is 0.395 kg/m
For 10 mm steel the weight is 0.616 kg/m
For 12 mm steel the weight is 0.888 kg/m
For 16 mm steel the weight is 1.578 kg/m
For 20 mm steel the weight is 2.466 kg/m
For 25 mm steel the weight is 3.853 kg/m
For 32 mm steel the weight is 6.313 kg/m
For 40 mm steel the weight is 9.865 kg/m

The above Unit Weight Of Steel has been fond out by using the formula  D²/162 .

2: Standard Conversion Factors:

1 inch = 25.4mm
1 feet = 0.3048 m
1 yard = 0.9144 m
1 meter = 3.28 ft
1 mm = 0.0394 inch
1 mile = 1.6093 km
1 newton = 0.10 kg(approx)

3: Concrete minimum clear cover for Reinforcement:
As per IS:456(200)

Raft Foundation Top          =50 mm
Raft Foundation Bottom    =75 mm
Raft Foundation Side         =75 mm
Beam clear cover               =25 mm
Strap Beam clear cover      =50 mm
Column  clear cover           =40 mm
Flat Slab                              =20 mm
Slab                                    =15 mm

4:Different Unit Weight of  Engineering Materials.

Aggregate   :1520-1620 kg/m³

Bitumen      :1340 kg/m³

Cement       :1440 kg/m³

Cast Iron     :7650 kg/m³

Steel            :7850 kg/m³

Ice               :913 kg/m³

Petrol          :690 kg/m³

Water          :1000 kg/m³

5: Concrete Grade Ratio:

For M5 concrete grades, the ratio   =      1:4:8
For M10 concrete grades, the ratio =      1:3:6
For M15 concrete grades, the ratio =      1:2:4
For M20 concrete grades, the ratio =      1:1.5:3
For M25 concrete grades, the ratio =      1:1:2
Here, M denotes Mix and M15 means the Compressive  strength of concrete gained after 28 days as 15N/mm2 (N = newton).

5: General Information:

The maximum chair spacing  =  1 meter

Minimum no. of bars in square column = 4 No’s

Minimum no. of bars in circular column = 6 No’s

Hook for stirrups one side = 9D

No. of stirrups = (clear span/spanning) + 1

Minimum diameter should be used in dowels rod = 12 mm.

Length of main steel in cantilever anchorage = 69D.

Curing for the Ordinary Portland cement are =10 days

Curing for the Cement with minerals and admixtures = 14 days.

Minimum diameter of main bars and distribution bars should be  in the slab = 8 mm

Maximum diameter of main bars and distribution bars should  in the slab = 1/8 of slab thickness , which is (slab thickness).