Spain's 1st National Concrete Congress: How Aggregate Quality Shapes Concrete

We represented our country at Spain's 1st National Concrete Congress, where new developments in construction and concrete were on the agenda, and introduced participants to the machines we build with the latest technology.

A congress speaks a different language from a trade fair: papers replace stands and methods replace products. Subjects such as structural concrete, strength classes and the behaviour of admixtures bring academics and people working in the field together in the same room.

From our point of view, the heart of the matter is aggregate.

Aggregate makes up most of the volume of concrete. The shape of the grains, the grading and the clay content of the material directly determine how much water the mix will need and the strength the concrete will finally reach. An aggregate with a high share of flaky and elongated grains gives lower strength at the same cement dosage.

That is why crusher selection is really a concrete question: the impact crushing stage gives the grains a cubical shape, while the washing stage removes clay and silt. The conversations we have at the congress usually start at exactly this point.