Road concrete: basic varieties, scope of application.

The history of construction of public roads and special purpose has many years of experience in the use of various building materials. But only with the beginning of the use of concrete did it become possible to build truly durable communication lines for various types of transport.

In this article we will talk about what constitutes a concrete pavement, what are the features of its manufacture and how it is used for its intended purpose. So, what is this unique building material and what distinguishes it from traditional types of cement-containing mortars?

The main features of the road concrete and concrete products based on them

Railway concrete, as well as analogues used in the laying of road links, belongs to the group of heavy dense cement-containing solutions.

Special requirements are imposed on this category of materials due to permanent mechanical loads, exposure to ultraviolet radiation, ingress of moisture and various chemical compounds. In addition, negative temperatures affect the road surface from year to year, which is especially important in relation to difficult domestic climatic conditions.

The road concrete in accordance with GOST must be distinguished by the following qualities:

• Acceptable price, in comparison with usual construction solutions;
• Frost resistance (parameters are calculated in accordance with the climatic features of the region);
• Resistance to mechanical stress;
• Abrasion resistance of the upper layer of the canvas;
• Hydrophobic coating (minimum degree of capillary leakage of moisture into the thickness of the plates);
• Resistance to ingress and long-term exposure to aggressive chemicals and compounds (including various fuels and lubricants);
• Accuracy of configurations and sizes (the shape and dimensions of concrete road slabs must comply with a uniform standard).

Scope of use of ready-made concrete goods

The GOST for road reinforced concrete slabs determines the use of these products as a base for building high-quality and durable roadway tracks, tramways and railways, airfields, etc. Also, in accordance with GOST 21924.0-84, slabs made of special high-quality concrete can be used in the construction of autobahns.

Main varieties and their composition

In accordance with the load on the surface of the coating and in accordance with the operating conditions of the roads, the following categories of concrete differ:

• for monolithic single-layer coatings;
• for two-layer coatings;
• for the device of the foundation of capital heavily loaded structures, such as airfields, main highways, etc.

Modern road concrete blocks are made with the use of lean concrete, which are characterized by a low content of Portland cement and an increased proportion of rubble. High strength of ready-made concrete products is achieved not due to the abundance of high-quality cement, but due to intensive sealing with special equipment. In the manufacture of blocks, instead of rolling, applied impact press.

Concrete road slabs can be monolithic structures, or, in accordance with the parameters of the design load, can be made in several layers with different composition and, as a result, different characteristics.

Important: Regardless of the number of layers and purpose, the plates must meet increased requirements in terms of durability, wear resistance, mechanical strength and resistance to the negative effects of external factors.

Features of industrial manufacturing

The concrete base for road signs, as well as the roadway itself, is produced using industrially manufactured solutions. Consider the features of their manufacture.

In the industrial manufacture of heavy concrete, plasticized or hydrophobic Portland cements are used as the basis. The content of the components that make up the finished solution varies in accordance with the specific use of the finished coating.

For example, in the formation of two-layer fragments of road routes, Portland cements with a grade of not lower than M-400 are used to make the upper layer. In addition, sand is used medium and large fractions, and mid-size crushed stone (grain size not more than 20 mm).

Important: The crushed stone used must have a compressive strength of at least 800 kg / m ?. In the manufacture of the solution for the formation of the lower layers, it is possible to use coarse crushed stone with a compressive strength of at least 600 kg / m ?. Also for this layer is allowed to use cements with a lower grade, for example, M-300.

In the industrial production of solutions for the installation of coatings responsible and loaded tracks located in difficult climatic conditions, the composition has special requirements in terms of frost resistance.

Instructions for the selection of ingredients that make up the solutions, takes into account the average monthly temperature indicators of the coldest season:

• In regions with an average monthly temperature of -15 ° C, concretes with a degree of frost resistance of F200 are used.
• In regions with an average monthly temperature of -5 ° C, mixtures with a frost resistance degree F150 are used;
• In other regions, mixtures with frost resistance F100 are used.

Often, for the construction of heavily loaded roads, the composition of casting mixtures is mechanized or mineral granules are added with their own hands. Such backfilling is compacted into the upper layers of the coating and increases its wear resistance, thus prolonging the service life of the web.

This technology is widely used in the construction of runways and runways of airfields, as well as in arranging access roads to loading and unloading terminals, etc.

Conclusion

Now you have a general idea of ​​the materials and technologies with which concrete road pipes and slabs are made. Knowledge of the production features and requirements for such concrete products allows you to choose the product that best suits your needs.

There are questions that need clarification? You can find more useful information by watching the video in this article.