What is the role of aggregate in concrete?

The primary role of aggregate in concrete is to provide structural support. Aggregates, which consist of coarse and fine particles, are essential in giving concrete its strength and durability. They form the bulk of the concrete mixture and help to distribute loads throughout the structure. By filling the spaces between the cement paste, aggregates also improve the overall stability and resistance of the concrete against various stresses.

While aggregates can influence other properties of concrete, such as its setting time and workability, their fundamental purpose is to act as a skeleton that supports the cement paste. This support is critical for the performance of the concrete, particularly in load-bearing applications. Therefore, understanding the role of aggregates in concrete composition is crucial for anyone working in construction or concrete design, as it directly impacts the structural integrity of the finished product.