Civil Engineering - Concrete Technology - Discussion

The given answer, "greatest surface area for the given cement and aggregates", is correct.

Yes, the right answer is B because the least surface area requires the least water EG rounded aggregate has the least surface area compared to others and requiring the least water for that.

The grading of aggregates in concrete affects the water requirement for a given workability. The water requirement is directly proportional to the surface area of the aggregates. The finer the aggregates, the greater the surface area, and the higher the water requirement to achieve the desired workability.

Therefore, the grading requiring the least amount of water is the one that gives the least surface area for the given amount of cement and aggregates.

When the surface area is least, it will obviously require least amount of water.

So, from my opinion, option B is correct.

The answer should be B. Because coarser aggregate have less surface area and required less mixing water for same degree of workability.

@Sanam.

Please explain it clearly.

@Sanam.

It Means as grade increase water required for greater surface area decreases.

For a given workability means it is fixed.

If we want same amount of easyness with that concrete paste then surface area should be low.

As we will increase fineness more area will absorb water and friction increases so can't give the same level of easyness means workability.

Given Answer is correct because finely grinded cement required less water and it cover more area.

Answer is correct as it's given that for a given workability.