1. Composition

Concrete is a mixture of sand, gravel and cement, the characteristics of which are determined by the proportion of each component.

Most of the time, the expected characteristics are well defined, but developing the right concrete can be a tricky business.

The composition variables are numerous:

• project constraints: mechanical characteristics, structure dimensions, reinforcement density, etc. ;

• site constraints: installation equipment, urban environment, climatic conditions, etc. ;

• concrete properties: workability, compactness, durability, appearance...

The more stringent the requirements, the more important it is to carefully study the concrete's composition.