PCI Level I and II Certification Practice Test

The type of aggregate that is retained on the #4 sieve is classified as coarse aggregate. This designation is based on the size of the particles in relation to the sieve mesh. The #4 sieve has openings that measure approximately 4.76 mm (or 0.187 inches).

Aggregate particles that are larger than this size do not pass through the sieve and thus are categorized as coarse aggregates. These kinds of aggregates are essential in construction for creating concrete mixtures, providing strength and durability to structures. Coarse aggregates typically include rocks, gravel, and crushed stone, which contribute to the structural integrity of concrete and asphalt pavements.

Fine aggregates, on the other hand, pass through the #4 sieve, and combined aggregates refer to a mixture of both coarse and fine aggregates, while superfine aggregates typically relate to even finer materials, which are not relevant in this context. Therefore, understanding the classification of aggregates by sieve size is crucial for proper material selection in construction applications.