RU2345967C1 - Cold mixture for repairing asphalt concrete pavements - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: present invention pertains to construction materials and can be used in repairing asphalt concrete pavements. Description is given of the mixture for repairing asphalt concrete pavements. The mixture contains mineral material and bitumen, and is distinguished by that, it contains solar oil, organic fatty acid, polyethylenepolyamine, nano-modified basalt micro-fibre and cellulose micro-fibre, in the following wt %: bitumen 4.5-7 wt % of crushed rock; solar oil 20-25 wt % of bitumen; organic fatty acid 8-16 wt % of bitumen; polyethylenepolyamine 5-12 wt % of bitumen; nano-modified basalt micro-fibre 1-3 wt % of bitumen; cellulose micro-fibre 3-5 wt % of bitumen.

EFFECT: increased frost resistance and water resistance of the newly coated section with considerable adhesion of bitumen to mineral particles.

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Description

The invention relates to the field of building materials and can be used in the repair and restoration work, in particular, in the repair of asphalt concrete pavements.

In the future, when describing the developed technical solution, the following terms will be used:

- “solar oil”. Hydrochloric oil is a product of the distillation of oil and coal tar, a specific gravity of 0.85, preferably used as diesel fuel, as well as a lubricant;

- microfiber - fibers whose length is less than 1 mm, and the thickness is less than 0.1 mm;

- nanomodified microfiber - microfiber fibers with carbon nanoparticles (nanotubes) deposited on them (10 ÷ 100) · 10 ^-9 m in size;

- the caking of the mixture is determined by the number of strokes of the falling load on the mixture laid by the cone, after which the mixture crumbles. Test conditions are defined in accordance with GOST 12801;

- the cohesion index characterizes the stability of the mixture to the effects of transport loads. Its determination is carried out using a device developed by SoyuzdorNII, according to the relative change in sample weight loss;

- resistance to delamination (GOST 31015) is determined by the runoff of bitumen after heating a portion of the mixture.

Known (SU, copyright certificate 975754, 1982) is a mixture containing bitumen, sand and industrial waste - heavy shale fusas, which include shale resin, water and the mineral part.

A disadvantage of the known mixture should be recognized as unsuitability for the repair of asphalt concrete coatings.

Also known (SU, copyright certificate 742407, 1980) is an asphalt mixture containing bitumen, sand and caprolactam production waste - spent filter powder tripoli.

A disadvantage of the known mixture should be recognized as unsuitability for the repair of asphalt concrete coatings.

Also known asphalt mixture according to GOST 9128-97 "Mixes asphalt road, airfield and asphalt" M., MNTKS, 1998, containing bitumen, mineral powder and sand.

A disadvantage of the known mixture should be recognized as unsuitability for the repair of asphalt concrete coatings.

As the closest analogue of the developed technical solution, one can recognize (Kozlova E.N. Cold asphalt. M., "Avtotransport", 1958, p. 42) the mixture composition containing mineral material (preferably, crushed stone of one fraction 5 ÷ 10 mm) and bitumen liquid or liquefied using thinners that are applied to the particles of the mineral material.

The disadvantage of this method can be recognized caking during storage, delamination of the mixture during storage, low frost resistance, low moisture resistance, as well as poor adhesion of bitumen, including liquefied, to the particles of mineral raw materials.

The technical problem solved by the developed technical solution is to obtain a composition suitable for the repair of asphalt concrete pavements.

The technical result obtained by the implementation of the developed composition is to increase the frost resistance and moisture resistance of the obtained new section of the asphalt concrete coating with significant adhesion of bitumen to mineral particles.

To achieve the proposed technical result, it is proposed to use a cold mixture for the repair of asphalt concrete pavements containing mineral material - crushed stone, bitumen, hydrochloric oil, organic fatty acid, polyethylene polyamine, nanomodified basalt microfiber and cellulose microfiber with the following mass ratio:

bitumen 4.5 ÷ 7.0% by weight of crushed stone, solar oil 20 ÷ 25% by weight of bitumen, organic fatty acid 8 ÷ 16% by weight of bitumen, polyethylene polyamine 5 ÷ 12 by weight of bitumen, cellulose microfiber 3 ÷ 5 by weight of bitumen, nanomodified basalt microfiber 1 ÷ 3% of the mass of bitumen.

The composition of the mixture can use any fatty (higher unsaturated) acids - stearic, palmetic, oleic, as well as production wastes containing these acids: tallow oil, decomposition products of natural fats, etc. It is preferable to use crushed stone of a narrow fraction, in particular a crushed stone fraction of 5 ÷ 10 mm.

Preferably, cellulose microfiber modified by applying a layer of lignosulfonate is used, preferably in an amount of 10-30% by weight of the cellulose microfiber.

Cellulose microfiber can also be used in granular form, while the granules contain an additional amount of bitumen, mineral powder, lignosulfonate in the following ratio, wt.%:

bitumen 20 ÷ 25, mineral powder 10 ÷ 15, lignosulfonate 5 ÷ 10%, cellulose microfiber rest.

As a mineral powder, finely ground (to sizes less than 100 microns) magnesium carbonate and / or calcium carbonate are mainly used.

The developed composition of the mixture includes both substances with acid groups (bitumen, hydrochloric oil, fatty acids) and substances with amino groups (polyethylene polyamine). As a result of their interaction in the bitumen film, a bulk frame structure is formed on the surface of particles of mineral material (pieces of crushed stone). The presence of double bonds in fatty acids, as well as the presence of microfiber, also contribute to the formation of this bulk structure. The amine groups of polyethylene polyamine additionally increase the adhesion of bitumen to the surface of pieces of crushed stone.

The use of nanomodified basalt microfiber in the mixture helps plasticize bitumen and reduce the consumption of hydrochloric oil, as well as structuring the mastic film on the surface of the crushed stone mineral material.

The use of cellulose microfiber in a mixture, including granular, helps to increase and retain bitumen mastic in the film, which leads to an increase in the durability of the mixture during its storage, as well as the service life of the asphalt concrete coating area repaired using the developed mixture.

When cellulose fiber is mixed with bitumen, molecules of their constituents interact due to hydrogen bonds, as well as Van der Waals forces, the action of which arises due to direct contact of aromatic rings of bitumen molecules with glucose residues of cellulose macromolecules. In addition, cellulose microfiber fibers absorb bitumen by the action of submicropores that penetrate the fibrous material of the fiber.

Modification of cellulose microfiber with lignosulfonate allows, due to the surface-active properties of lignosulfonate molecules, to create a moisture film on the surface of the formed granules of cold asphalt, which prevents caking of the granules of the mixture. The hydrophilicity of cellulose microfiber, the fibers of which are on the surface of granules of cold asphalt, also affects the formation of a moisture-protective film on the surface of the granules.

When preparing the mixture, the mixture of bitumen and solar oil is initially heated to a temperature of about 100 ÷ 120 ° C. In the resulting heated mixture of bitumen and hydrochloric acid, polyethylene polyamine and fatty acid are added with stirring to obtain a mastic. At the same time, crushed stone is heated to a temperature of 60 ÷ 100 ° C. Heated crushed stone is mixed with microfiber. Then, with mixing, mastic is poured into the mixture of crushed stone and microfiber. The resulting granules are cooled to ambient temperature, packaged in bags and stored until use.

The resulting mixture is applied to places of asphalt concrete pavement to be repaired. It is advisable to clean the repair site from contamination before applying the mixture.

There are two options for repairing the road surface.

According to the first option, the place to be repaired is filled with granules of a cold mixture and subsequent leveling of the laid cold mixture and compaction with any suitable vibration equipment.

According to the second option, the granules of the mixture are poured into the place to be repaired with a slide, which is then leveled and compacted by the slopes of a passing vehicle.

In the future, the invention will be disclosed using the following implementation examples.

Example 1

Bitumen in an amount of 5 kg is placed in a container for preparing the mixture, solar oil in an amount of 1.25 kg, is heated with stirring to a temperature of 110 °. Polyethylenepolyamine in an amount of 0.3 kg, oleic acid in an amount of 0.5 kg is added to the preheated mass and mixed until a homogeneous mass is obtained. Heated 100 kg of crushed stone fractions 5 ÷ 10 mm to a temperature of 80 ° C and mixed with 0.1 kg of nanomodified basalt microfiber and 0.2 kg of cellulose microfiber. While mixing in a concrete mixer, the obtained mastic is poured into a mixture of crushed stone and microfiber. The resulting granules after cooling are placed in containers.

The caking parameter of the resulting product was 3 strokes with acceptable values of 1-5 strokes; cohesion index - 75% with a norm of at least 65%; resistance to delamination - 0.18% with a norm of not more than 0.20%.

Example 2

The experimental conditions correspond to the experimental conditions of example 1, but used: bitumen in an amount of 6 kg, hydrochloric oil in an amount of 1.3 kg, oleic acid in an amount of 0.7 kg, polyethylene diamine in an amount of 0.4 kg, nanomodified basalt microfiber in an amount of 0.12 kg, granular cellulose microfiber in an amount of 0.25 kg, a mixture of bitumen and solar oil was heated to a temperature of 120 ° C, crushed stone to a temperature of 90 ° C.

The caking parameter was 3 strokes (within the norm of 1-5 strokes); cohesion index - 80% (above the lower limit of the norm - 0.65%); resistance to delamination - 0.15% (below the upper limit of the norm - 0.20%).

Example 3

The conditions of the experiment correspond to the conditions of the experiment in example 1, but used: bitumen in the amount of 4.0 kg, hydrochloric oil in the amount of 0.6 kg, oleic acid in the amount of 0.5 kg, polyethylene polyamine in the amount of 0.3 kg, nanomodified basalt microfiber in an amount of 0.05 kg, granulated cellulose microfiber in an amount of 0.10 kg, a mixture of bitumen and solar oil was heated to a temperature of 100 ° C, crushed stone to a temperature of 60 ° C.

The caking parameter was 2 strokes (normal 1-5); cohesion index - 45% (below the norm of 0.65%); caking resistance - 0.12% (normal - less than 0.20%).

Example 4

The experimental conditions correspond to the experimental conditions of example 1, but used: bitumen in an amount of 5 kg, hydrochloric oil in an amount of 1.5 kg, oleic acid in an amount of 0.6 kg, polyethylene diamine in an amount of 0.4 kg, nanomodified basalt microfiber in 0.15 kg, granular cellulose microfiber in an amount of 0.15 kg, a mixture of bitumen and solar oil was heated to a temperature of 100 ° C, crushed stone to a temperature of 60 ° C.

The caking parameter was 5 strokes (normal); cohesion index - 70% (normal); resistance to delamination - 0.35% (above normal).

Example 5

The experimental conditions correspond to the experimental conditions of example 1, but used: bitumen in an amount of 6 kg, hydrochloric oil in an amount of 1.2 kg, oleic acid in an amount of 0.9 kg, polyethylene polyamine in an amount of 0.5 kg, nanomodified basalt microfiber in 0.18 kg, granular cellulose microfiber in the amount of 0.30 kg, a mixture of bitumen and solar oil was heated to a temperature of 100 ° C, crushed stone to a temperature of 100 ° C.

The caking parameter was 1 hit (normal); cohesion index - 85% (normal); resistance to delamination - 0.10% (normal).

Example 6

The experimental conditions correspond to the experimental conditions of example 1, but used: bitumen in an amount of 7 kg, hydrochloric oil in an amount of 1.75 kg, tal oil (in terms of oleic acid) in an amount of 1.05 kg, polyethylene polyamine in an amount of 0, 7 kg, nanomodified basalt microfiber in an amount of 0.2 kg, granular cellulose microfiber in an amount of 0.35 kg, a mixture of bitumen and solar oil was heated to a temperature of 90 ° C, crushed stone to a temperature of 70 ° C.

Caking parameter - 4 strokes (normal); cohesion index - 80% (normal); resistance to delamination - 0.20% (normal).

Example 7

The experimental conditions correspond to the experimental conditions of example 1, but used: bitumen in the amount of 8 kg, hydrochloric oil in the amount of 2.4 kg, oleic acid in the amount of 2.0 kg, polyethylene polyamine in the amount of 0.8 kg, nanomodified basalt microfiber in 0.2 kg, granular cellulose microfiber in the amount of 0.3 kg, a mixture of bitumen and solar oil was heated to a temperature of 120 ° C, crushed stone to a temperature of 90 ° C.

The caking parameter is 7 strokes (above normal); cohesion index - 80% (normal); resistance to delamination - 0.6% (above normal).

Example 8

The experimental conditions correspond to the experimental conditions of example 1, but used: bitumen in the amount of 8 kg, hydrochloric oil in the amount of 2.4 kg, oleic acid in the amount of 0.7 kg, polyethylene polyamine in the amount of 0.4 kg, nanomodified basalt microfiber in 0.32 kg, granular cellulose microfiber in an amount of 0.24 kg, a mixture of bitumen and solar oil was heated to a temperature of 130 ° C, crushed stone to a temperature of 100 ° C.

The caking parameter was 10 strokes (above normal); cohesion index - 60% (below normal); resistance to delamination - 1.30% (above the norm).

The invention used allows to increase the adhesive ability, frost resistance and moisture resistance of the obtained repair coatings of asphalt concrete.

Claims (8)

1. Cold mixture for the repair of asphalt concrete pavements containing mineral material and bitumen, characterized in that it additionally contains hydrochloric oil, organic fatty acid, polyethylene polyamine, nanomodified basalt microfiber and cellulose microfiber in the following ratio, wt.%:
bitumen 4.5 ÷ 7% by weight of crushed stone solar oil 20 ÷ 25% by weight of bitumen fatty organic acid 8 ÷ 16% by weight of bitumen polyethylene polyamine 5 ÷ 12% by weight of bitumen nanomodified basalt microfiber 1 ÷ 3% by weight of bitumen cellulose microfiber 3 ÷ 5% by weight of bitumen 2. The mixture according to claim 1, characterized in that it contains oleic acid as an organic fatty acid. 3. The mixture according to claim 1, characterized in that as the carrier of an organic fatty acid it contains tal oil. 4. The mixture according to claim 1, characterized in that it contains a fraction of crushed stone 5 ÷ 10 mm 5. The mixture according to claim 1, characterized in that the cellulose microfiber modified by applying a layer of lignosulfonate is used. 6. The mixture according to claim 5, characterized in that the mass of lignosulfonate is 10-30% by weight of cellulose microfiber. 7. The mixture according to claim 1, characterized in that granular cellulose microfiber is used. 8. The mixture according to claim 7, characterized in that the granules of cellulose microfiber contain:
bitumen 20 ÷ 25 wt.% mineral powder 10 ÷ 15 wt.% lignosulfonate 5 ÷ 10 wt.% cellulose microfiber rest