The civil engineer has to perform many activities at the construction site and there are certain works which are repetitive in nature. So, some tips and point which a civil engineer should remember for faster calculations as well as quick solutions to construction site problems.
Important for Civil Site Engineer :
Following are some important points to remember for civil site engineers to make the construction work easier while maintaining a quality of construction.
- Lapping in reinforcement is not allowed for the bars having diameters more than 36 mm.
- Steel Char maximum spacing is 1.00 m (or) 1 No per 1m2.
- In steel dowels, rod minimum of 12 mm diameter should be used.
- Steel Chairs minimum of 12 mm diameter bars to be used.
- Longitudinal reinforcement should not less than 0.8% and more than 6% of gross C/S.
- Minimum bars used for a square column is 4 No’s and 6 No’s for the circular column.
- Main bars used 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.
- The minimum thickness of the slab should be 125 mm.
- Dimension tolerance for concrete cubes + 2 mm.
- Freefall of concrete is allowed maximum to 1.50m height.
- Lap slices shall not be used for bar larger than 36 mm.
- Water absorption of bricks limited not more than 15 %.
- PH value of the water used should not be less than 6.
- The minimum Compressive strength of Bricks is 3.5 N / mm2.
- Binding wire required in steel reinforcement is 8 kg per Metric tonne.
- For soil filling work as per IS code, 3 samples should be taken for core cutting test for every 100m2.
Density of Materials
Bricks – 1600 – 1920 kg/m3
Concrete block – 1920 kg/ m3
Reinforce Concrete – 2310 – 2700 kg/ m3
Curing Time for Concrete Members for various type of cement:
Super Sulphate cement: 7 days
Ordinary Portland cement OPC: 10 days
Minerals & Admixture added cement: 14 days
De-Shuttering period of different RCC Members
1)The period for columns, walls, vertical formworks – 16-24 hrs.
2) period for Soffit formwork to slabs – 3 days (props to be refixed after removal)
3) The period for Soffit to beams props – 7 days (props to refixed after removal)
4) Beams spanning up to 4.5m – 7 days
5) Beams spanning over 4.5m – 14 days
6) Arches spanning up to 6m – 14 days
7) Arches spanning over 6m – 21 days
Minimum Nos. Of Cube sample for given Volume of concrete:
1 – 5 m3 = 1 Nos.
6 – 15 m3 = 2 Nos.
16 – 30 m3 = 3 Nos.
31 – 50 m3 = 4 Nos.
Above 50 m3 = 4 + 1 Nos.