The Importance of Proper Aggregate Sizing in Concrete Slabs

What is the relationship between aggregate size and the depth of a concrete slab?

a) Aggregate size should be equal to slab depth
b) Aggregate size should be half the slab depth
c) Aggregate size should be one-third the slab depth
d) Aggregate size is unrelated to slab depth

Answer:

The maximum size of the aggregate used in the concrete mix should not exceed one-third of the depth of the slab.

In the field of civil engineering, the sizing of aggregate in relation to the depth of a concrete slab is crucial for the structural integrity of the slab. The correct answer is c) Aggregate size should be one-third the slab depth. This standard is established to ensure that the concrete mix can properly fill the forms and create a structurally sound slab.

Excessively large aggregate can prevent the concrete from thoroughly filling confined spaces, resulting in the formation of voids. These voids can weaken the overall strength of the concrete slab and compromise its durability over time. By limiting the size of the aggregate to one-third of the slab depth, engineers can optimize the concrete mix to achieve a dense and uniform mixture that can effectively support the load requirements of the slab.