Tuesday, May 6, 2014

// // Leave a Comment

Points That Site Engineer Should Remember

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 slices 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
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
Arches spanning over 6m
21 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

0 comments:

Post a Comment