Chapter 10 Concrete

Concrete a composite man-made material is the most widely used building material in the construction industry. In a concrete mix, cement and water form a paste or matrix which fills the voids of the fine aggregate and binds them together. The major factors responsible for wide usage of cement-concrete are mouldability, early hardening, high early compressive strength, development of desired properties with admixtures to be used in adverse situations, suitability for guniting, pumpability and durability. The simple reason for its extensive use in the construction of almost all civil engineering works is that the properties can be controlled within a wide range by using appropriate ingredients and by special mechanical, physical and chemical processing techniques. Concretes are classified as lime concrete, gypsum concrete and cement concrete. Most of the ancient structures and historical buildings had been constructed with lime concrete. The preparation of concrete consists in selecting the materials, batching the ingredients and mixing.