Civil Engineering Today

  Aggregates Aggregates are raw materials that are produced from natural sources and extracted from pits and quarries, crushed stone and recycled concrete, used in construction. Aggregates are the major and important constituent of concrete. They form the body of the concrete as it occupies 70–80% of the volume of concrete. Although aggregates were originally considered to be inert material, they have recently been found to be chemically active to some extent. Cement is the only factory-made component, whereas aggregates (both coarse and fine) and water are naturally available materials. Aggregates are the important constituents of the concrete which give body to the concrete and also reduce shrinkage.     Classification of Aggregates I.   Classification of Aggregates Based on Size: Aggregates are available in nature in different sizes. The size of aggregate used may be related to the mix proportions, type of work etc. The size distribution of aggregates ...