RU80168U1 - DEVELOPMENT OF ROAD CLOTHES - Google Patents

Abstract

The device of pavement, consisting of the upper bearing layer of the pavement and the base in the form of a volumetric geogrid with filler, characterized in that the cells of the geogrid are filled with monolithic non-autoclave foam concrete.

Description

The utility model relates to road construction and, in particular, to the device of pavement.

The prior art.

A traditional pavement device is known, consisting of a top layer of fine-grained asphalt concrete and a layer of crushed stone (Polymer film materials in road construction. M, 1982, pp. 29-39).

The achievement of the required technical result in the specified technical solution is prevented by the occurring shear stresses in the crushed stone layer at operational loads.

A pavement device is known comprising an upper layer of asphalt concrete pavement, an intermediate layer and a lower layer. made of a geogrid of a cellular structure from interconnected seams of polymer strips, the cells of which are filled with sand. (US Patent No. 4797026. NCI 404/28, 1989). When sand is compacted, asphalt concrete is laid, and when loads from asphalt are transferred during road operation, the walls of the geogrid are damaged, which is facilitated by the heterogeneity of the material in the cells of the geogrid. In turn, all this leads to damage to the asphalt concrete pavement.

The prototype closest to the utility model is a pavement device according to the utility model patent No. 55791, consisting of an upper layer and a lower layer.

The top layer is made of granular material, for example, crushed stone or sand of medium size. The bottom layer is made of geogrid, the cells of which are filled with granular material, such as sand, gravel, gravel, or any combination of these materials. After being placed in the grates, the granular material is compacted with a roller. The cellular geogrid is made of polymer strips interconnected by seams.

The disadvantage of this design is the impossibility of obtaining uniformity of the pavement layer, since when filling individual cells, the height of the filler layer changes and when rolling, material of different densities is obtained. The use of heavy equipment for

rolling increases the cost of construction and can damage the construction of the road, because rollers and sharp edges of rubble or gravel during rolling can damage the walls of the geogrid.

The essence of the utility model.

To obtain a homogeneous layer of pavement and reduce the cost of construction due to the abandonment of heavy road equipment, monolithic non-autoclave foam concrete is placed in the cells of the geogrid, flush with the walls or slightly higher than the walls of the geogrid. In addition to these advantages, the use of foam concrete improves thermal protection and reduces the load on the ground, which is essential for the construction of roads on weak and heaving soils. The density of the foam concrete is selected based on the calculation of design loads and thermal protection requirements.

The proposed device pavement consists of a top layer made for example of asphalt or reinforced concrete. And the lower layer of the geogrid, the cells of which are filled with monolithic non-autoclave foam concrete, flush or slightly higher than the height of the walls of the geogrid. An additional layer of foam concrete over the geogrid allows the passage of heavy equipment without damaging the walls of the geogrid when laying asphalt or an additional intermediate layer. So, if necessary, gravel can be laid on top of a geogrid with foam concrete, in this case, when rolling gravel, damage to the walls of the geogrid does not occur. A geogrid of a cellular structure can be made of polymer strips interconnected by seams or otherwise formed. The material, thickness and height of the walls of the geogrid and the density of foam concrete may vary based on strength and heat engineering requirements. If it is necessary to improve thermal protection, the cells of the geogrid contain foam concrete of different densities - denser on the top with better mechanical characteristics, less dense at the bottom with better thermal characteristics. There may be an additional layer of foam concrete under the geogrid to improve thermal performance, as well as the use of blocks and plates of expanded polystyrene placed in foam concrete. This design allows you to place any layers of the top road surface on the geogrid with foam concrete, including asphalt concrete itself. The use of such a technical solution allows:

- evenly distribute loads and prevent their destructive effect on the upper layers and the underlying subgrade of pavement;

- to provide thermal protection of the soil, which is especially important for heaving soils and in permafrost areas;

- carry out work in areas where there are problems with the presence of crushed stone, sand or gravel;

- to technologically simplify and speed up the work, as the foam concrete is produced on the spot, fed over long distances through the hose and does not require vibration;

- refuse to use heavy equipment and other means to seal this layer of pavement;

- increase the operational reliability and service life of the pavement;

The utility model is illustrated by the following drawings.

Figure 1 - geogrid poured into the cell foam concrete lying on any base;

Figure 2. - pavement made of polystyrene foam blocks and geogrid filled with foam concrete;

Figure 3 - pavement of polystyrene blocks fastened with foam concrete and geogrid filled with foam concrete;

Figure 4 - pavement made of solid foam with polystyrene inserts and geogrid filled with foam;

Figure 5 - pavement of solid foam and geogrid filled with foam.

Options for implementing a utility model.

Figure 1 shows a cross-section of a volumetric geogrid 3, in the cells of which a monolithic non-autoclave foam concrete 2 is poured, covering the geogrid 3. Asphalt concrete or any other coating is laid on top 1. Geogrid 3 is installed on any base 4 - soil, drainage or other intermediate layer of pavement . It is possible to fill foam concrete flush with the top of the walls of the geogrid, but it is preferable to fill it with a layer of 30-150 mm above the walls of the geogrid, as this protects it from damage when laying asphalt concrete or other pavement, as well as during the operation of the road. This is also advisable in the case when crushed stone is laid and rolled over the geogrid based on the requirements of the project. Foam concrete 2 in the geogrid 3 and on top of it can be poured either of the same density or different, based on the requirements of the project in terms of loads and heat-shielding properties. Pouring of different density of foam concrete into the cells of a high geogrid is also possible - lower heat-insulating from 200 kg / m3 below, and structural above from 600 kg / m3 to 1200 kg / m3. Foam concrete may contain various

bulk fillers - sand, ash from burning sewage sludge, fly ash of thermal power plants, foam glass, expanded clay, polystyrene granules, etc. Geogrid 3 can be made of polyethylene, polypropylene and other plastics, have different heights, cell configurations and wall thicknesses, which can be solid or with holes.

Figure 2 presents a variant of the pavement, where on the blocks 5 of extruded polystyrene foam, lying on the base 4, a layer 6 of pavement from a volumetric geogrid and monolithic foam concrete is laid on top of which asphalt concrete or another type of pavement is laid 1. With this option, the pavement compulsory laying on top of sand layers of at least 300 mm thick is not required to prevent damage when moving heavy equipment used for laying overlying layers of pavement. The sides of the embankment 7 can be formed using sand, geogrid, etc.

Figure 3 shows asphalt concrete 1 laid on a layer 6 of geogrid with foam concrete, but, in contrast to the variant shown in figure 2, the blocks or panels 5 of extruded polystyrene foam are laid at intervals, for example 40-50 mm, into which monolithic foam concrete is poured 2, preferably with a density of 200-600 kg / m3, having good adhesion to polystyrene foam. The result is a single monolithic structure. This is especially important when using low-profile blocks and slabs, their small pieces, which is caused by the cutting of blocks at the turning points of the road. In such cases, the blocks and their fragments are difficult to fix using mechanical fasteners and they are easily displaced relative to each other.

Figure 4 shows asphalt concrete 1 laid on a layer 6 of geogrid with foam concrete, and layer 6 laid on a monolithic foam concrete 2 with inclusions of polystyrene foam blocks or sheets 5 to facilitate embankment and improve thermal insulation properties. At a high height of the embankment, foam concrete is poured in layers of 400-700 mm to prevent its shrinkage.

In Fig. 5, the asphalt concrete 1 and the layer 6 of the geogrid with foam concrete are resting on a layer-by-layer, monolithic foam concrete 2, which forms the main bulk of the embankment.

When pouring foam concrete according to the options depicted in figure 3 and figure 4 to prevent the emergence of blocks of polystyrene foam with the help of cargo are fixed from the ascent and horizontal movements. The main bulk of the foam concrete embankment, taking into account the heat engineering and strength requirements, can consist of several layers of foam concrete of different densities, in particular from 100 kg / m3 to 600 kg / m3. Foam concrete in

the main bulk of the embankment may contain various fillers as well as foam concrete poured into geogrid cells. It is possible to use fabrics from geosynthetics between any layers of pavement.

Claims (14)

1. The device of pavement, consisting of the upper bearing layer of the road surface and the base in the form of a volumetric geogrid with filler, characterized in that the cells of the geogrid are filled with monolithic non-autoclave foam concrete. 2. The pavement device according to claim 1, in which the geogrid with foam concrete is mounted on a light embankment. 3. The pavement device according to claim 2, in which the light embankment is formed by compactly stacked polystyrene foam blocks. 4. The pavement device according to claim 2, in which the light embankment is formed by polystyrene foam blocks laid at intervals in which a monolithic non-autoclaved foam concrete is poured. 5. The pavement device according to claim 2, in which the light embankment is formed by a monolithic non-autoclave foam concrete. 6. The pavement device according to claim 5, in which expanded polystyrene blocks are placed in the foam concrete. 7. The pavement device according to claim 1, in which the foam has a density of 200-1500 kg / m ³ . 8. The device of pavement according to claim 7, in which the foam contains bulk filler. 9. The pavement device of claim 8, in which the filler is sand. 11. The pavement device of claim 8, wherein the filler is ash. 11. The pavement device of claim 8, in which the filler is expanded polystyrene. 12. The pavement device of claim 8, in which the filler is foam glass. 13. The device of pavement according to claim 8, in which the filler is expanded clay. 15. The device of pavement according to claim 5, characterized in that the foam concrete is poured in layers with a density of 100-600 kg / m ³ .