In the production of quality shotcrete or shotcrete, it is necessary to have a ‘recipe’ in which the appropriate proportions of the different materials to be mixed are indicated.
But simply a recipe is not enough, since the way in which the different components are mixed as well as the sequence in which they are mixed has an important impact on quality.
This post covers the basic requirements of a concrete plant and its role in the final quality of shotcrete.
Shotcrete, mixers & kneaders
As we have mentioned previously, in the batching plants, the person responsible for mixing the concrete, and therefore for its homogeneity and quality, is the mixer equipment.
In mixing plants, it is the mixer that is responsible for the homogeneity and quality of the concrete, which makes it a crucial element
The capacity of the mixer will determine the number of cycles or mixes needed to load the mixer.
Example: If the mixer of the concrete plant is 1 m3, the plant will need to perform 4 mixes of 1 m3 to fill the 4 m3 Mixer
To determine the efficiency of a mixer, one of the crucial aspects to take into account is the homogeneity and quality of the shotcrete produced. For a high-quality finish such as shotcrete, vertical mixers are usually used, as they produce a very homogeneous mixture in the shortest possible time.
Vertical mixers consist of a cylindrical bowl with a set of mixing arms and scrapers. The angle of attack of the paddles and agitators will be the key to creating a uniform mix.
To avoid excessive wear, the arms usually have damping supports and both these and the linings are covered with high resistance to abrasion steel.
