Everything about rolled concrete

Rolled concrete is a special form of concrete, which has a special composition, and also otherwise differs greatly from conventional concrete. Where to use rolled concrete, what disadvantages it has, and how it is assembled and installed, you can read in this post.

Use of rolled concrete

Rolled concrete is used exclusively in road construction. There it forms either the base course for the asphalt surface or, in exceptional cases, the top layer. Non-reinforced rolled concrete, however, is not particularly high quality. This is his biggest disadvantage. The rough surface layer is problematic in road construction.

Only in the US are rolled concrete cover layers widely used for road construction, in Europe the quality of the top layer is considered too low and only in exceptional cases rolling concrete is used in road construction.

Another use is offered as a stable industrial floor. Again, there is usually a cover, usually with industrial screeds, so that the rolled concrete also forms only the support layer here.

composition

With regard to the concrete composition, the rolled concrete differs from conventional concretes. It has a very low cement content, which is normally in the range of around 80-150 kg / m³. This is much less than traditional concretes in construction.

It is possible to distinguish between the so-called low cementitious RCC (Roller Compacted Concrete = rolled concrete) and high cementitious RCC according to the cement content. The former have a cement content of around 90 kg / m³, the high cementitious in practice around 150 kg / m³ cement content.

Installation and processing

When processing in road construction, installation takes place via so-called road pavers. They apply the rolled concrete in layer thicknesses of around 18 - 20 cm and first compact it. Thereafter, the built-in rolled concrete is compacted again with a smooth roller. With particularly high demands on the carrying capacity, layers of greater thickness (usually 25 cm) are installed, but this is the exceptional case. Only in the construction of dams, where rolled concrete is also used, layer thicknesses of 30 cm are common during installation.

Rolled concrete industrial floors are a comparatively expensive and seldom used form of floor covering. In some cases, rolled concrete can be an interesting alternative to other forms of flooring. It is a cost effective alternative to other floor coverings and can be built very fast and with high accuracy. Often, industrial hall floors are also built in multiple stages to avoid construction damage.

Tips & Tricks

In road construction, additional pozzolans are used to reduce the heat of hydration of the rolled concrete when setting. These special rocks have been created by the action of heat and in connection with water and calcium hydroxide bindable. The main chemical constituents of the pozzolans are silica, limestone or iron oxides. At the same time they also ensure a higher strength of the end product. The reaction that these substances form is known as the so-called pozzolanic reaction. Pozzolans are also found in mortar.

Video Board: How to lay roller compacted concrete