We study the importance of humidity in concrete manufacture

One of the most important aspects in the process of manufacturing concrete is the measuring of humidity in the raw material. This article will therefore delve into the information. And, for this, our source has been an article from Concreto Online.

The truth is that today’s concrete plants already dose the quantities of raw material depending on the formula they want to make. And in these cases, there is a sand - cement - water ratio responsible for ensuring the proper consistency.

This is why if only weighed amounts of sand were taken into account in the concrete manufacturing process, the formula of each batch would vary due to humidity for the extra water added and the smaller amount of sand.

Water-cement ratio formula for manufacturing

We now use a graph in the Concrete Online article to know the importance of the water-cement ratio, and see how it can affect concrete properties (strength, consistency or durability). As we read in the article, "knowing the moisture in the sand is an effective solution to maintain this ratio batch after batch and to save raw material...”

Let"s see an example:

Here we find data/an example of a concrete manufacturing process. And, ”as can be seen, the amount of extra water will make it necessary to use more cement to assure the targeted water/cement ratio, with the extra cost that this entails.”

Finally, ”once the materials have been dosed into the mixer and while they are being mixed, it is important to monitor the humidity because it is a factor that determines the desired consistency.”

Therefore, ”knowing the humidity in real time in the mixer will allow the right amount of water to be dosed to reach the target humidity before unloading.” Controlling this humidity will be very important, since the homogeneity of the product will depend on it. This aspect will also allow us control over quality, consumption and time.

Mixers for Concrete Plants

As we can read in the Concreto Online article:

Sensors in the mixer allow the humidity to be continuously measured in dosing the raw material. Furthermore, if they are connected to the plant control equipment, the degree of humidity in the concrete will be able to be controlled before unloading.

In the graph below we can see how it works:

Manufacture of concrete and the existing regulations in Spain for humidity measurement

In Spain, the manufacture of concrete is regulated by two regulations:

• Structural Concrete Instruction (EHE-08)

• Technical Instruction for controlling production of the concretes manufactured in plant, Royal Decree 163/2019.

The graph below shows the maximum water-cement ratio in manufacturing, as established in the regulations:

Concrete plants at Poyatos

Now that we have delved into the importance of humidity control in concrete manufacture, we would like to show you the machinery that Poyatos has for Concrete Plants.

In order to offer ”turnkey” plants, at Poyatos we manufacture Concrete Plants that carry out the whole process of dosing, transporting and mixing… by offering mixers and Planetaries. Each of these are presented below:

Mixers for Concrete Plants

As we can read on our own website:

In Mixers, the tank is fully lined in the bottom and sides. It has special screw-on and replaceable anti-abrasive sheet steel plates.

The arms of the blades in Concrete Plant Mixers are mounted in articulation. They are also cushioned by hard rubber silent-blocks. The arms are also self-adjusting and replaceable, easily accessible and fully protected from dust. The pulleys are made of anti-abrasive NI-HARD cast iron.

On the following link, you can download the pdf with all the information and in the graph below, you can see the production, capacity and power of the MF model:

Planetaries

We go back to our website to read about this machinery:

This is a state-of-the-art mixer patented by Poyatos for concrete plants. It has a turbine of mixing blades with planetary movement and a group of turbo blades (the turbo-planetaries combine the advantages of a planetary mixer with those of a "turbo": homogeneity and fast mixing, together with a speedy unloading).

And the graph below shows the capacity, power and production of the MP model (download the pdf here with all the information):