Precast concrete, fresh concrete and ready-mixed concrete - the differences

Concrete can be produced in different ways, and various concrete products can be obtained through trade. They each have their own advantages and disadvantages, which you must remember and should know. What you should know is explained in detail in this post.

variety of terms

Those who do not build or concretes themselves often have difficulties with the individual terms. Occasionally, something is confused here again and again.

Ready-mixed concrete is the kind of concrete that you can buy mixed in sacks in the building materials trade or in the hardware store. It only needs to be mixed with the right amount of water and is ready to use. If the correct amount of water is used, the manufacturer guarantees the strength and properties of the concrete.

Fresh concrete is either fresh concrete mixed on site. The concrete composition depends on the particular application. The mixing ratio can be adjusted individually.

Ready-mixed concrete is concrete produced in a concrete plant, which is delivered via a mixing truck. In general, these transport vehicles also contain devices with which you can pump the concrete directly to the installation site via a pipe, such as when casting a floor slab. The concrete manufacturer guarantees for the quality and the integrity of the concrete, unless it comes to admixtures of other materials on customer request - such as the delivery of steel fiber concrete.

Quality differences

With ready-mixed concrete, you can always assume that the concrete manufacturer ensures perfect quality - after all, he is contractually liable for it. The concrete meets all the requirements prescribed by DIN, the formulations are precisely adhered to and the quality of the concrete tested.

In ready-mixed concrete, especially the addition of water is problematic. Changing the so-called water cement value of the concrete, ie the ratio between water and cement, also changes the strength of the concrete. Certain other properties also vary with the water cement value. An examination of the concrete on its properties or its mixing ratio is limited - but experts often recognize when processing, if the concrete has too much or too little water. Mixing must also be done in the right way for precast concrete.

With fresh concrete, which one produces even on the construction site, that is even more problematic, since the mixing ratio is usually not completely accurate, and one adds the so-called mixing water only after rough estimates. It is also important here that the concrete, if it is gradually produced in the mixing machine, does not always have a consistent quality but can be different. That too can be a problem. In addition, certain additives are missing, such as those contained in ready-mixed concrete or in ready-mixed concrete. They often significantly improve the properties and processability of the concrete.

Cost differences

When there is a great need for concrete and enough workers on the construction site, ready-mixed concrete is almost always the cheapest solution. In many cases, it is also the most technically sensible, such as when a floor slab is to be concreted. Here a continuous concreting without interruption for the quality of the bottom plate may well be crucial.

The self mixing of fresh concrete is usually worthwhile only at small, required quantities at all. Prefabricated concrete, however, has some advantages, with mostly the same costs:

  • exact recipe of the concrete
  • Additives that improve the properties of the concrete
  • Guaranteed quality and strength just by adding the right amount of water.

Video Board: SITE MIX CONCRETE vs READY MIX CONCRETE || Civil Engineering Basics