RU2599658C2 - Method for producing sand asphalt concrete - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: invention relates to road construction, namely to a technology of preparing asphalt concrete mixtures for top and bottom coating layers of road pavements of automobile roads, cycling paths and pavements and platforms. Method involves preparation of a mixture consisting of, wt%: sand - grinding screenings of strong rocks sized - 0.1-10 mm - 31.0; natural quartz sand sized 0.1-5 mm - 31.0-7.0; limestone mineral powder - 12.0 viscous bitumen - 5.2-3.3 (over 100 wt%). Mineral part includes cold milled granular asphalt sized 0-10 mm in the amount of 26.0-50.0 % from the weight of the mineral part of the mixture or in the amount of 24.7-48.4 % from the mixture weight.

EFFECT: increased strength of asphalt concrete for coatings and bases in dry and water-saturated conditions, increased heat resistance, increased water resistance and increased crack resistance.

1 cl, 2 tbl

Description

The invention relates to road construction, and in particular to a technology for the preparation of asphalt mixes for the device of the upper and lower layers of road pavement of roads, bicycle paths, sidewalks and sites.

Known compositions of hot fine and coarse asphalt mixes according to STP 5718-001-04000633-06, prepared with additives of cold milling asphalt granules in the amount of 5-25% (wt.) Types A, B, C, D and D of grades 1, 2 and 3 and compositions of cold asphalt concrete of type D _x (RF patent No. 2412127) with additives of cold milling asphalt granules fr. 0-15 mm in the amount of 6.5-7.5% by weight of the mixture.

As a prototype, the technical solution described in GOST 9128-2009 was selected, which shows the compositions of type D sandy concrete mixes without the addition of cold milling asphalt granules for the device of the upper and lower layers of coatings and bases of road clothes of roads, sidewalks, bicycle paths and platforms.

The technical result is an increase in the strength of asphalt concrete for coatings and substrates in dry and water-saturated conditions, heat resistance, water resistance and crack resistance, while other indicators meet the requirements of GOST 9128-2009 for sand type D asphalt concrete. At the same time, cheaper work is achieved due to the use of mineral composition in the new asphalt granulate constituents and bitumen binder.

The technical result is achieved by the fact that the method of producing sand asphalt for the device of the upper and lower layers of coatings, including the preparation of a sand asphalt mixture, consisting of, by weight. %: sand - screenings crushing strong rocks fr. 0.1-10 mm - 31.0; sand of natural quartz fr. 0.1-5 mm - 31.0-7.0; limestone mineral powder - 12.0 and viscous bitumen - 5.2-3.3 (in excess of 100 wt.%). According to the invention, cold milling asphalt granulate is introduced into the mineral part. 0-10 mm in an amount of 26.0-50.0% by weight of the mineral part of the mixture or in an amount of 24.7-48.4% by weight of the mixture.

Sandy asphalt concrete mix is prepared in commercially available asphalt mixing plants equipped with an additional line (device) for automatic dosing and feeding asphalt granulate into the mixer. The accuracy of dosing sand - screenings of crushing of hard rocks, natural quartz sand, asphalt granulate must comply with accuracy class 2 according to GOST 10223 and GOST 30124. The accuracy of dosing of limestone mineral powder and viscous bitumen is ± 1.5%, wt.

Examples of specific performance of the proposed method are given in table. 1, and the values of the indicators of the properties obtained by sand asphalt concrete - in table. 2.

Table 1. Compositions of asphalt concrete, wt.% Examples (asphalt granulate content,% by weight of the mixture Compositions of asphalt concrete, wt.% (By weight of the mixture) Hard Rock Crushing Screenings Natural quartz sand Limestone Mineral Powder Asphalt granulate Viscous bitumen - BND 60/90 one 31 57 12 0 7.0 2 31 52 12 5 6.6 3 31 47 12 10 6.3 four 31 42 12 fifteen 5.9 5 31 37 12 twenty 5,6 6a 31 31 12 26 5.2 6 31 27 12 thirty 4.8 7 31 17 12 40 4.0 8 31 7 12 fifty 3.3 9 31 2 12 55 3.0 10 0 0 0 one hundred 0 11 (according to GOST 9128-2009) 84.0-90.0 10.0 16-0 6.0-9.0

Table 2. Properties of the resulting sand asphalt Examples (asphalt granulate content,% by weight of the mixture) Shear resistance Crack resistance
at ± 0 ° С,
at speed
deformations
50 mm / min, MPa R50, MPa R20, MPa R _in , MPa K _in clutch coefficient of internal friction 5 (20) 0.38 0.72 3.35 1,50 4.01 3.73 0.93 6a (25) 0.39 0.72 3.30 1,52 4.11 3.97 0.93 6 (30) 0.41 0.72 3.25 1.55 4.21 4.11 0.93 7 (40) 0.42 0.72 3.13 1,60 4.40 4.11 0.93 8 (50) 0.42 0.72 3.00 1.70 4,50 4.23 0.94 9 (55) 0.43 0.73 2.65 1.72 4.60 4.35 0.95 11 (according to GOST 9128-2009) not less than 0.54 not less than 0.65 (for the 2-3rd CDZ) 3.0-6.5 not less than 1.30 2.2 - not less than 0.85

Information sources

1. GOST 9128-2009. Mixes asphalt concrete road, airfield and asphalt concrete. Specifications (Prototype).

2. STP 5718-001-04000633-2006. Enterprise standard. Mixes asphalt concrete road, airdrome, prepared with the addition of granulate of old asphalt concrete. Technical conditions Developed and introduced by JSC ABZ No. 4 “Kapotnya”, LLC “Dorekspert”, GUP “NIMosstroy” with the participation of “SoyuzdorNII”.

3. RF patent for the invention No. 2412127 IPC С04 / В 26/26, Auth. Salikhov M.G., Krivorotov A.A., Weinstein E.V., publ. 02/20/2011. Bull. No. 5.

Claims (1)

A method of obtaining sand asphalt concrete for the device of the upper and lower layers of coatings, including the preparation of sand asphalt concrete mixture, consisting of, wt.%: Sand - screenings crushing strong rocks fr. 0.1-10 mm - 31.0; sand of natural quartz fr. 0.1-5 mm - 31.0-7.0; limestone mineral powder - 12.0 and viscous bitumen - 5.2-3.3 (in excess of 100 wt.%), characterized in that asphalt granulate cold milling fr. 0-10 mm in an amount of 26.0-50.0% by weight of the mineral part of the mixture or in an amount of 24.7-48.4% by weight of the mixture.