What is the difference between coarse and fine aggregates?

The distinction between coarse and fine aggregates is primarily based on their size, which is critical for construction and engineering applications. Coarse aggregates are defined as those that are larger than 4.75 mm in size. This size classification means that coarse aggregates typically include gravel and crushed stone used in making concrete and for various construction purposes.

Fine aggregates, on the other hand, are smaller than 4.75 mm, encompassing sand and other granular materials that can enhance the cohesiveness and workability of concrete mixtures. Understanding this size differentiation is essential for selecting the appropriate materials in concrete design and ensuring that the mixture achieves the desired strength and durability.

Recognizing the correct size categorization helps in correctly assessing material properties, mixing design, and ensuring that the intended application, such as drainage, stability, or strength, is achieved. Thus, the definition provided in the correct answer highlights the essential criteria for distinguishing between coarse and fine aggregates, which is size.