How Does a Concrete Mixer Truck Work? A Complete Guide

Concrete mixer truck is a vital machine in any construction project to transport ready-mixed concrete. It has a truck body, hydraulic system, and rotating mixing drum to ensure concrete maintains its quality during transportation from the batching plant to the construction site.

There are many different types of concrete mixer trucks depending on project specifications. The different drum sizes are 4m³, 6m³, 8m³, 10m³, 12m³, and 14m³.

1. Concrete Loading Process

The working process starts at the concrete batching plant. Fresh concrete that contains cement, sand, gravel, water, and other materials is loaded into the drum through the feeding hopper at the back of the truck.

During loading process, the drum continues turning all the time. Spiral blades fitted in the drum assist in moving and blending of the materials uniformly to provide even quality of concrete before transport.

Loading and drum turning processes should be controlled well. Failure to control them may lead to concrete overflow or uneven blending in the drum.

2. Mixing and Transportation of Concrete

Once the loading is done, the concrete mixer moves to the construction site by rotating the drum at a low speed.

This low-speed process is termed as the agitation process. The primary reason for using agitation is to keep the concrete components from separation and maintain the consistent condition of the concrete. However, unlike the mixing process, agitation process is not designed for remixing the concrete.

When the drum is static for a long time, the separation between cement and aggregates may occur and make the concrete not work in the same way as originally. In extreme cases, the solid concrete could stay in the drum and become hard to clean.

During the long-distance transportation process, the driver must pay attention to drum speed, delivery time, and working conditions. If the project takes place in a warm climate or far away, some special steps like the use of concrete additives might be needed.

3. Process of Discharging of Concrete

Once arrived at the construction site, the operator turns the direction of rotation of the mixing drum.

The concrete will then be moved towards the discharge point by the internal spiral blades. The concrete will go through the chute and be discharged in different construction zones including foundations, concrete pumps, roads, and building structures.

The discharging rate of the concrete can be controlled by adjusting the drum rotation rate. Unloading process smoothly and steadily leads to higher efficiency in construction process, reduction of the material loss and improved results of the project.

Conclusion

In the working process of concrete mixer truck, there are three critical stages involved – loading, transportation with agitation, and discharging. By virtue of the cooperation of the truck frame, hydraulic system and mixing drum, the concrete mixer trucks are capable of ensuring concrete quality and construction efficiency.

Selection of the right capacity and structure of concrete mixer trucks is essential in different construction situations.