Concrete Aggregate

Description

A broad term to describe coarse material used in the manufacturing of concrete, such as sand, crushed stone, gravel and recycled concrete. Serving as an overall strength enhancer, aggregate material makes up a large portion of the total volume of concrete. It is important to consider all technical elements when starting a project, as the aggregate material vary in composition from one area to another.

Considering factors when selecting aggregate for use in concrete:

• Surface: Volume ratio of the concrete as affected by shape and size of elements
• Total cementitious content
• Environment and exposure conditions of the concrete
• Total water content in the fresh concrete
• Degree of hydration or cementing reaction
• Water: Cement ratio
• Type of binder and cement characteristics such as gypsum or alkali content
• Aggregate type

“Extracts taken from “shrinkage” by Nick Doulgeris”

 Material Specifications:

• Ensure that the aggregate doesn’t contain any deleterious material when batching concrete as this can have a negative effect on the mix.
• To ensure the control of cement content in the mix, one should be aware of the water demand of the fine aggregate.