Civil Engineering - Concrete Technology - Discussion

GRADING LIMITS FOR FINE AGGREGATES.

Sieve Size Percentage of Passing For,
Grading
Zone-I

Grading
Zone-II

Grading
Zone-III

Grading
Zone-IV

10 mm 100 100 100 100
4.75 mm 90 " 100 90 " 100 90 " 100 95 " 100
2.36 mm 60 " 95 75 " 100 85 " 100 95 " 100
1.18 mm 30 " 70 55 " 90 75 " 100 90 " 1000
600 micron 15 " 34 35 " 59 60 " 79 80 " 100
300 micron 5 " 20 8 " 30 12 " 40 15 " 50
150 micron 0 " 10 0 " 10 0 " 10 0 " 15

Zone-I represents the coarse sand and zone-IV represents the finer sand in all the four zones. Hence correct answer should be D.

Finer sand required more water so Answer D is correct.

D is the correct answer.

I think option a) is correct, because same volume coarse sand required more water.

Correct answer zone-4, because zone - 4 more surface area compare to zone -1.

Yeah;

It is zone 4. Because of more surface area.

I think Zone 4 because fine sand having large surface area so w/c ratio will more require to lubricant.

Zone 1.

It is asked about w/c ratio, not about only water. Zone 1 sands are coarser so they have the comparatively lesser surface area, so they require a lesser amount of cement hence higher w/c ratio.

Yes, right @Sultan.

In w/c, Water is In numerator so sand requiring more water will have more w/c ratio.