THE EFFECT OF REPLACEMENT OF NATURALS AGGREGATES BY SLAG PRODUCTS ON THE STRENGTH OF CONCRETE

The aggregates (sand and gravel) form the skeleton of the concrete; they occupy approximately 75% of its volume, and intervene directly on the physical and mechanical properties of concrete. The aim objective of this experimental work consists in: -Substituting sand by granulated blast furnace slag. -Substituting natural gravels by crystallized slag. The use of the method of substitution permits to improve the strength of the concrete, to increase the production of building materials in Algeria and to protect the environment, it also gave an economic approach to the construction industry. The experimental results obtained show that the partial substitution of ordinary sand by slag gives better results compared with the ordinary concrete, the total substitution of natural gravels by crystallized slag improves the strength, but the full replacement of fine and coarse aggregates by slag products affect negatively the strength of concrete.