The base transfers the load to the underlying layer, which in turn transfers it to the soil. Two layers are distinguished in the coating: – the upper – a layer of wear, provides the evenness of the coating and perceives tangent efforts from the crews and the lower – the supporting layer that perceives vertical forces.
The presence and dimensions of structural elements of road clothes, t. e. The thickness of the coatings, bases and underlying layers depend on:
1) movement intensity;
2) the calculated load (rolling stock);
3) the climatic area of the road;
4) hydrogeological conditions for the construction of the road
(dry places, raw places with a temporary or permanent influx of water);
5) ground canvas.
Depending on the method of laying on the subgrade, road clothing is distinguished by three types: 1) a sickle profile; 2) a semi -terminal profile; 3) Bloom profile.
So ground roads, soil, improved engraving and optimal mixture, as well as gravel with a thickness of the coating of up to 15-16 cm are arranged by a sickle-shaped profile. Gravel coatings with a large thickness are arranged in a semi -wrap or in a trough. All other types of coatings are arranged in the trough. The device of road clothing simultaneously with the earthen canvas due to precipitation of the latter can cause undesirable deformations of the coating.
Therefore, it is recommended to lay lane clothing through a certain period of time required to sediment the subgrade. However, the sediment of the subgrade occurs for a very long time, measured for years, which modern terms and methods of construction cannot allow. Therefore, it is necessary to carry out a thorough density of the soil during the construction of the subgrade (rolling, tamping, vibration, etc. D.).
When arranging road clothing, various methods of the device of the side of the subgrade can be used.
