What is the lowest sieve size that is retained in fine aggregate?

The correct answer is #8, as fine aggregates are defined as materials that pass through a #4 sieve (4.75 mm) and are mostly retained on a #200 sieve (0.075 mm). The term "fine aggregate" generally refers to particles that are too small to be classified as coarse aggregate but larger than a specific limit.

In the context of the American Society for Testing and Materials (ASTM) standards, and particularly for concrete applications, fine aggregates are commonly retained on the #8 sieve (2.36 mm) when looking to find the typical range of aggregate sizes used. This sieve size indicates that the aggregates being tested are primarily composed of particles that fall within a specific range for optimal performance in mixtures, especially for concrete or asphalt.

Understanding the gradation of fine aggregates is critical, as it influences the workability, strength, and durability of the final concrete product. Therefore, focusing on materials that are typically retained above this sieve size helps ensure a balanced mixture capable of achieving desired mechanical properties in construction.