RU2586644C1 - Method for elimination of local depressions on asphalt concrete coating of motor roads - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: invention relates to road construction, namely to methods of elimination of local depressions on asphalt concrete coating of motor roads. Method of elimination of local depressions on asphalt concrete coating of motor roads includes cleaning of depression, arrangement of granulated asphalt concrete mixture of bitumen and filler into it and formation of local coating. At that, walls and bottom preliminarily cleared local recesses are steeped with flammable liquid and combustible element of corrugated sheet material is placed at bottom, e.g. cardboard, after placing on it, similar to cover, support element of meshy material, for example, polymer fibre or glass fabric, and then on support element granular asphalt mix of bitumen and coarse mineral filler is laid with layer necessary for filling of recesses, and before formation of seal coating on recess is burning corrugated combustible element in it by its ignition from burning combustible fluid on surfaces of recesses and air supply under support element by its delivery with pump.

EFFECT: simplified method implementation, reducing of material consumption and labour intensity.

1 cl, 1 dwg

Description

The invention relates to the field of road construction, in particular to methods for eliminating local depressions on the asphalt road surface. It is known that the operation of roads is inevitably associated with the appearance of defects on the road surface that arise both under the influence of car traffic and under the influence of natural and climatic factors and the initial quality of the road surface. First of all, local recesses (depressions, pits), edge destruction, breaks and other coating defects should be attributed to them [1].

Known methods for patching the pavement with an asphalt mixture using hot and cold technologies [2].

When using hot technology, the quality of paving is high, but its implementation depends on weather conditions and the accuracy of adhering to the technology, including hard temperature conditions. To a lesser extent, this effect affects the use of cold bitumen-containing mixtures and materials based on liquid or liquefied bitumen. It should be borne in mind that the strength and water resistance of cold asphalt concrete prepared on liquid or liquefied bitumen is 2 ... 3 times lower than hot.

Currently patching of pavements is recommended [3] to be performed at air temperatures not lower than + 5 ° C, and in autumn at + 10 ° C. In conditions of lowering the air temperature below -10 ° C, repair of the coating is recommended to be carried out with mixtures based on viscous and liquid road bitumen grade BND-200/300 or SG-130/200. All this necessitates the repair of road surfaces in winter to warm up the defective place, and then place hot asphalt mixture in this place.

However, this method of repair in winter conditions has the following disadvantages:

- heating a defective place requires the use of energy-intensive devices;

- preparation of hot asphalt mixes at the repair site is associated with the use of expensive small-sized plants;

- the delivery of the hot mixture to the place of repair is associated with the inevitable cooling of the mixture, which significantly affects the quality of the coating.

A close analogue of the invention is a method for granulating a hot asphalt mixture and a method for using this mixture for repairing asphalt coatings in winter conditions [4].

The method of granulating a hot asphalt mixture is that it is placed in a mixer with water in small parts and continuously mixed. At the same time, the water temperature at the beginning of the granulation process is at least + 90 ° C, and during mixing, the temperature of the water in the mixer gradually decreases and is brought to + 30 ° C.

In the process of mixing in water and cooling the water to + 30 ° C, the hot asphalt mixture is converted into granules of various sizes, respectively, of crushed stone, gravel, sand in the composition of the mixture at a water temperature of + 30 ° C, which freely roll in water and do not stick together, and after granules are unloaded from the mixer and stored under a canopy.

The very method of using granular asphalt concrete mix for repairing asphalt concrete pavements in winter conditions consists in preparing a cold asphalt concrete mix by mixing granular asphalt concrete mix with a light hydrocarbon thinner of bitumen, at least kerosene, and the percentage of bitumen thinner in the composition of the bitumen temperature-reducing air mixture with temperature constantly increasing.

The disadvantages of this method, implemented by cold technology, are:

- strength and water resistance obtained after repair of asphalt concrete 2 ... 3 times lower than that formed by hot technology;

- the preparation of cold asphalt mixes is associated with a high consumption of diluent, i.e. kerosene or gasoline, which, after laying in a defective place, evaporates, polluting the environment;

- before laying the cold asphalt mixture in a defective place, heating and priming with bitumen on its surface is required.

The objective of the invention is the combination of the operations of heating and priming with bitumen of the surface of the local recess with the simultaneous plasticization of bitumen asphalt mix to a viscous state directly at the workplace.

This is achieved by the fact that the walls and the bottom of the previously stripped recess are moistened with a combustible liquid and a combustible element of corrugated sheet material, for example cardboard, is placed on the bottom, after which, like a bedspread, a supporting element of sheet mesh material, for example, polymer fiber or fiberglass, is placed on it. Then, a granular asphalt-concrete mixture of bitumen and coarse mineral filler is laid on the support element with a layer necessary to seal the recess, and before forming a seal from it at the recess site, the corrugated combustible element is burned in it by providing it with ignition of combustible liquid on the surfaces of the recess and air supply under the support element by pumping it with a pump.

Placing corrugated sheet material on the bottom of the recess of the corrugated sheet material allows you to create some free air space between the bottom of the recess and the supporting element, necessary to ensure ignition of the combustible element and its combustion when the air is forced into the combustion zone. When high-temperature combustion products pass through the layer of mixture granules at the point of contact and the recess walls, fusion of the surface layer of bitumen is observed, which leads to monolithization of the entire mass of granules without a sharp change in the air space in the combustion zone. In addition, this is facilitated by the presence of a deviation from a right angle, for example up to 75 °, of the location of the walls of the recess formed during the cleaning of a defective place on the road surface.

Typically, the roadbed of roads, as a rule, includes (Fig. 1, a, b) compacted soil base 1, base 2 of crushed stone, stone, concrete, etc. and pavement 3, in particular, in this case consists of an asphalt mixture.

The special advantages of the proposed method were confirmed by the possibility of its implementation by using improvised tools and materials (Fig. 1, a, b). To do this, on a pavement 3 made of asphalt concrete mixture with a local defect in the form of a depression (pit), it was cleaned using available tools (crowbar, chisel, hammer, brush) 300 × 300 mm in size and 45 mm in depth. The walls 4 and the bottom 5 of the local recess were wetted with kerosene with a brush; at the bottom 5 of the recess, a corrugated combustible element 6 was made of sheet cardboard 2 mm thick and with a corrugation height of 12 mm with a step between them of 10 mm. Then, above the local recess, there was a supporting element 7 in the form of a polymer network (cell size 3 × 3 mm) with a base thickness of 1.2 mm and a size of 300 × 300 mm (Fig. 1, a). Next, resting on the edge of the wall 4 of the recess and focusing on the corrugated combustible element 6, a tubular tip 8 with a rubber hose 9 was installed to supply air from the pump with a foot drive (in Fig. 1, and not shown) under the support element 7. When burning a combustible element 6, the products of its combustion, passing through the porous layer of the asphalt mix 10, led to a change in the state of bitumen of the asphalt mix, i.e. various degrees of plasticization, from solid to liquid on the surface of its bitumen and to the viscous flowing rest of its mass. In this case, heating and priming 11 (Fig. 1, b) of surfaces 4 and 5 of the local recess was also provided. At the end of combustion of the combustible element 6, the tubular tip 8 was removed from the recess outward, and then a local coating was formed with the mixture compacted with a wooden rammer (Fig. 1, b).

This method combines the advantages of both cold and hot technologies for the repair of pavements, including:

- ease of implementation at the workplace in a wide range of air temperatures without the use of expensive devices and materials;

- low material consumption and labor intensity.

Information sources

1. Silyanov V.V. Transport and operational qualities of roads and city streets: a textbook for students. higher textbook. institutions / V.V. Silyanov, E.R. Domke. - 3rd ed., Erased. - M.: Publishing Center "Academy", 2009. - 352 p.

2. www.OSl.ru/article/rood-equipment/2006-5-A-2006-09-29-18-11-55/.

3. Guidelines for the repair and maintenance of public roads. - M.: Rosavtodor, 2004.

4. RF patent for the invention No. 2367630, IPC C04B 26/26, E01C 7/10. The method of granulation of asphalt mixes and the method of using this mixture for the repair of asphalt pavements in winter conditions / B.C. Prokopets, O.A. Rychkova, S.F. Filatov, - Publ. 09/20/2009, Bull. No. 26.

Claims (1)

A method for eliminating local depressions on an asphalt concrete pavement of roads, including cleaning the depressions, placing a granular asphalt mix of bitumen and filler in it and forming a local coating, characterized in that the walls and the bottom of the previously cleaned local depression are moistened with a combustible liquid and a combustible element made of bottom is placed corrugated sheet material, for example cardboard, after having, on it, like a bedspread, a supporting element of sheet mesh material, for example measures of polymer fiber or fiberglass, and then a granular asphalt-concrete mixture of bitumen and coarse mineral filler is laid on the support element with the layer necessary to seal the recess, and before forming the seal on the recess, the corrugated combustible element is burned in it by ensuring its ignition from burning flammable liquid on the surfaces of the recess and air supply under the support element by pumping it with a pump.

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