USEFUL CIVIL ENGINEERING TIPS FOR SITE ENGINEERS

Following are the basic tips you should be remembered while working on construction sites:

1.GRADE OF CONCRETE:

• M5 - 1:4:8
• M10 - 1:3:6
• M15 - 1:2:4
• M20 - 1:1.5:3 
• M25 - 1:1:2 

2.CLEAR COVER TO MAIN REINFORCEMENT:

• Footings - 50mm
• Raft Foundation(Top) - 50mm
• Raft Foundation(Bottom) -75mm
• Raft Foundation(Side) - 75mm
• Beam - 25mm
• Strap Beam - 50mm
• Column - 40mm
• Slab - 15mm
• Flat Slab - 20mm
• Stair Case - 15mm
• Retaining Wall - 20 to 25mm
• Water Retaining Structures - 20 to 30mm .

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1. Maximum Water Absorption by bricks - 15% 
2. Compressive Strength of Bricks - 3.5 N/mm^2 
3. Density of Bricks - 1600 to 1920 Kg/m^
4. Minimum Thickness of Slab - 125mm
5. Dimension Tolerance for Cubes - +2 
6. Maximum Freefall of Concrete - 1.50m
7. Laping should not be use for the bars having larger dia than 36mm 
8. Binding wire required for steel reinforcement - 8Kg per MT
9. Maximum chair spacing - 1m
10. Minimum dia should be ised in dowels rod - 12mm
11. Hooks for Stirrups(1side) - 9D
12. No.of.Stirrups=(clear span/spanning+1)
13. Length of main steel in cantilever anchorage - 69D 
14. Minimum no.of bars in square column - 4
15. Minimum no.of bars in circular column - 6 
16. Minimum dia of main bars and distributors in the slab - 1/8 of slab thickness.

All reinforcements should be free from mill scales,loose rust,and coats of paints,oil or anyother substances.

3.SETTING TIME:

• Initial setting time should not be less than 30minutes.

• Final setting time should not be greater than 10hours.

4.REQUIRED CURING DAYS:

• Super Sulfate Cement - 7days
• Ordinary Portland Cement - 10days
• Cement with minerals and admixtures - 14days

5.SLUMP VALUE(IS-456):

• Lightly Reinforced Concrete - 25 to 75mm
• Heavily Reinforced Concrete - 75 to 100mm
• Trench Fill - 100 to 150mm(for in-situ & tremie)