In this Article today we will cover about the Points to Remember for Civil Site Engineer or Construction Engineer | Density of Materials | Curing Time of RCC Members for Different types of Cement | De-Shuttering time of Different RCC Members | Cube Sample Requirements | Grade of Concrete | Clear Cover to Main Reinforcement | Setting Time | Required Curing Days | Slump Values
Following are few general points to remember for civil site engineers to make the construction work easier while maintaining quality of construction.
- - Lapping is not allowed for the bars having diameters more than 36 mm.
- - Chair spacing maximum spacing is 1.00 m (or) 1 No per 1m2.
- - For dowels rod minimum of 12 mm diameter should be used.
- - Chairs minimum of 12 mm diameter bars to be used.
- - Longitudinal reinforcement not less than 0.8% and more than 6% of gross C/S.
- - Minimum bars for square column is 4 No’s and 6 No’s for circular column.
- - Main bars in the slabs shall not be less than 8 mm (HYSD) or 10 mm (Plain bars) and the distributors not less than 8 mm and not more than 1/8 of slab thickness.
- - Minimum thickness of slab is 125 mm.
- - Dimension tolerance for cubes + 2 mm.
- - Free fall of concrete is allowed maximum to 1.50m.
- - Lap splices not be used for bar larger than 36 mm.
- - Water absorption of bricks should not be more than 15 %.
- - PH value of the water should not be less than 6.
- - Compressive strength of Bricks is 3.5 N / mm2.
- - In steel reinforcement binding wire required is 8 kg per MT.
- - In soil filling as per IS code, 3 samples should be taken for core cutting test for every 100m2.
DENSITY OF MATERIALS
Material
|
Density
|
Bricks
|
1600 – 1920 kg/m3
|
Concrete block
|
1920 kg/ m3
|
Reinforced concrete
|
2310 – 2700 kg/ m3
|
CURING TIME OF RCC MEMBERS FOR DIFFERENT TYPES OF CEMENT
Super Sulphate cement: 7 days
Ordinary Portland cement OPC: 10 days
Minerals & Admixture added cement: 14 days
DE-SHUTTERING TIME OF DIFFERENT RCC MEMBERS
Arches spanning over 6m 21 days
RCC Member
|
De-shuttering time
|
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
|
CUBE SAMPLES REQUIRED FOR DIFFERENT QUANTITY OF CONCRETE
Quantity of Concrete
|
No. of cubes required
|
1 – 5 m3
|
1 No’s
|
6 0 15 m3
|
2 No’s
|
16 – 30 m3
|
3 No’s
|
31 – 50 m3
|
4 No’s
|
Above 50 m3
|
4 + 1 No’s of addition of each 50 m3
|
GRADE OF CONCRETE:
M5 – 1 : 4 : 8
M10 – 1 : 3 : 6
M15 – 1 : 2 : 4
M20 – 1 : 1.5 : 3
M25 – 1 : 1 : 2
CLEAR COVER TO MAIN REINFORCEMENT:
Footings : 50 mm
Raft Foundation (Top) : 50 mm
Raft Foundation (Bottom) : 75 mm
Raft Foundation (Side) : 75 mm
Beam : 25 mm
Strap Beam : 50 mm
Column :40 mm
Slab : 15 mm
flat Slab : 20 mm
Staircase : 15 mm
Retaining Wall : 20 – 25 mm
Water Retaining Structures : 2 0- 30 mm
SETTING TIME:
Initial setting time should not be less than 30 minutes.
Final setting time should not be greater than 10 hours.
REQUIRED CURING DAYS:
Super sulfate cement – 7 days
Ordinary portland cement – 10 days
Cement with minerals and admixtures – 14 days.
SLUMP VALUE (IS-456):
Lightly reinforced concrete: 25 – 75 mm.
Heavily reinforced concrete: 75 – 100 mm.
Trench fill : 100 – 150 mm ( for in-situ & tremie).
Conclusion:
Full article on Points to Remember for Civil Site Engineer or Construction Engineer | Density of Materials | Curing Time of RCC Members for Different types of Cement | De-Shuttering time of Different RCC Members | Cube Sample Requirements | Grade of Concrete | Clear Cover to Main Reinforcement | Setting Time | Required Curing Days | Slump Values. Thank you for the full reading of this article in "QA QC Civil Engineering" platform in English. If you find this post helpful, then help others by sharing it on social media.
Full article on Points to Remember for Civil Site Engineer or Construction Engineer | Density of Materials | Curing Time of RCC Members for Different types of Cement | De-Shuttering time of Different RCC Members | Cube Sample Requirements | Grade of Concrete | Clear Cover to Main Reinforcement | Setting Time | Required Curing Days | Slump Values. Thank you for the full reading of this article in "QA QC Civil Engineering" platform in English. If you find this post helpful, then help others by sharing it on social media.