RU2447035C1 - Dense organomineral mixture - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to road construction and repair, and can be used in making coating layers. The dense organomineeral mixture contains mineral material - granite macadam, grinding screenings, mineral powder, cement, basalt fibre and class 3 slow-decomposing cationic bitumen emulsion, which contains bitumen BND 90/130, cationic emulsifying agent KADEM-VT, stabilising additive OXYPAV-A.30, water, with the following ratio of components, wt %: mineral material 87.00 - 92.00, cement 1,50 - 2,35, basalt fibre 0.20 - 0.55, bitumen BND 90/130 3.40-5.50, cationic emulsifying agent KADEM-VT 0.40 - 0.50, stabilising additive OXYPAV-A.30 0.20 - 0.40, water 2.30 - 3.70.

EFFECT: high quality of road surfaces owing to improved strength characteristics at 20 and 50°C, and high water resistance.

1 ex, 8 tbl

Description

The invention relates to the construction and repair of roads and can be used to arrange coating layers.

Asphalt concrete in the coating works in very difficult conditions, it is influenced by a number of different factors related to both traffic and climatic conditions. Traffic is associated with the impact of a single or multiple, simultaneous or long-term load on an asphalt pavement. The climatic conditions of some areas of road construction are characterized by high summer temperatures and low winter temperatures, as well as high rainfall.

The upper layers of coatings must ensure high performance of the roadway, which includes the protection of structural underlying layers from access to atmospheric moisture, from aging, and provide waterproofness, which is an indispensable condition for the longevity of roads.

Recently, technologies for the production of organic-mineral mixtures using cationic bitumen emulsions prepared on viscous road bitumen that meet the requirements of GOST 22245-90 have been firmly introduced into the practice of road construction.

Known organic-mineral mixture for coating roads with emulsified organic binders in conjunction with active additives (see interstate standard GOST 30491-97 "Mixtures of organic-mineral and soil reinforced with organic binders for road and airfield construction. Technical conditions").

The disadvantage of this organic-mineral mixture for road coatings is the low compressive strength at temperatures of 20 ° C and 50 ° C (respectively, no less than MPa 1.8 and 0.9), water resistance especially with prolonged water saturation (at least 0.7 )

Closest to the proposed invention in technical essence and the achieved result is a dense emulsion-mineral mixture (see patent RU for invention No. 2183600), including mineral material 85.0-89.0% and slowly decaying cationic bitumen emulsion 11.0-15, 0% Bitumen-mineral mixture has a high coefficient of water resistance and adhesive properties of bitumen emulsions. However, the resulting emulsion-mineral mixture does not have sufficiently high strength characteristics, to prepare the mixture, an increased emulsion consumption (11.0-15.0%) is required and its component composition is very complicated and requires the use of a component that is almost not found at present - fusa (phosphatide concentrate )

The objective of the invention is to improve the quality of pavement by improving the properties of organomineral mixtures used in the construction of coatings: strength characteristics at 20 ° C and 50 ° C (R ^cr ₂₀ and R ^cr ₅₀ ), water resistance coefficient, and the possibility of formation of cationic bitumen emulsion 3 class, as well as reducing the consumption of binder (bitumen emulsion).

The essence of the invention lies in the fact that a dense organic-mineral mixture containing mineral material (granite crushed stone, crushing screenings, mineral powder), cement and slowly decaying cationic bitumen emulsion of class 3, including bitumen, a cationic emulsifier, water, while additionally containing mineral material mineral wool (basalt fiber), and the bitumen emulsion - a stabilizing additive of tertiary amine oxides "OXIPAV-A.30" in the following ratio of components, wt.%:

Mineral material 87.00-92.00 bitumen BND 90/130 3.40-5.50 water 2.30-3.70 cationic emulsifier "KADEM-VT" 0.40-0.50 OKSIPAV-A.30 0.20-0.40 mineral wool (basalt fiber) 0.20-0.55 cement 1,50-2,35

The hydrogen pH of the emulsifier used was in the range of 1.8-2.0, which was achieved by the gradual introduction of hydrochloric acid into the aqueous KADEM-VT solution.

The technical result consists in the following: the introduction of mineral wool (basalt fiber) —waste from building heat-insulating materials into the mixture — improves its mechanical properties. The pores of the fibers, filling with a bituminous binder, thereby create the reinforcement of the coating, increasing its strength, shear and crack resistance, as well as greater resistance to bending and tensile loads. This is due to the fact that mineral wool (basalt fiber), according to the classification of rocks, refers to alkaline rocks and when interacting with bitumen, a carrier of certain oxygen, sulfur and nitrogen compounds, cotton wool will contribute to the chemisorption processes of acidic materials that bind to the surface of mineral materials (in this granite crushed stone was used in the work), the adsorption on which usually has only a physical character.

Chemisorption processes and molecular-surface phenomena associated with the adsorption of a binder change the structure of the boundary layers of bitumen and affect the properties of organomineral mixtures, increasing the above indicators.

The surface-active substance OXIPAV-A.30, a water-soluble tertiary amine oxide, was used as an emulsion stabilizer. The product is a good emulsifier, has a thickening effect. The introduction of “OXIPAV-A.30” into the composition of the emulsion in combination with the KADEM-VT emulsifier makes it possible to obtain emulsions of the third class (cationic bitumen emulsion of the EBK-3 class) and directionally regulate some properties of cationic bitumen emulsions: slow the decay rate, viscosity, increase adhesion to mineral materials, both basic and acidic in nature, lower the temperature of brittleness and impart elastic properties to the binder. The specified emulsion in combination with mineral binders (in our case, cement) when combined with stone materials provides the preparation of high-quality organic-mineral mixtures for road coatings that exceed the requirements of GOST 30491-97 “Organic-mineral mixtures and soils, fortified with organic binders, for road and airfield construction . Technical conditions. " The resulting mixtures have an increased coefficient of long-term water resistance of 7-9%, their strength at 20 ° C is more than 2 times, the strength index at 50 ° C reaches values of 1.45-1.52 MPa, i.e. mixtures exhibit increased heat resistance at high temperatures.

An analysis of the known technical solutions showed that the use of organomineral mixtures with emulsified organic binders in conjunction with mineral binders is known. However, their properties are not characterized by such high indices that they show in the claimed solution, namely: increased coefficient of water resistance, strength characteristics at 20 ° C and 50 ° C, which contributes to improvement, shear resistance, water and corrosion resistance of the road surface.

CHARACTERISTICS OF INITIAL MATERIALS

1. Mineral materials

Granite crushed stone of the Pavlovsky quarry of the Voronezh region of a fraction of 5-15 mm, screening crushing of crushed stone of a fraction of 0-5 mm and mineral powder were used as mineral material. Table 1 shows the grain composition of these materials and the selected composition of the organo-mineral mixture (finished mixture), which meets the requirements for organoral mixtures according to GOST 30491-97 (table 1).

Used mineral powder meets the requirements of GOST R 52129-2003.

2. Bitumen

Viscous oil road bitumen BND 90/130 was used. Table 2 presents its physical and mechanical properties. In terms of physical and mechanical properties, bitumen meets the requirements of GOST 22245-90.

3. Mineral wool (basalt fiber)

Cotton wool is a waste of mineral wool (basalt), used as a heat-insulating material in construction and industry for surface insulation with temperatures up to 700 ° C. Mineral wool is a product of high-temperature roasting of basalt chips. Physico-chemical characteristics of the VM used in this work are given in Table 3. Mineral wool (basalt fiber) meets the requirements of GOST 4640-93 (Mineral wool. Technical conditions, table 1).

4. The stabilizer of the decay rate of the bitumen emulsion OKSIPAV-A.30

This modifier refers to nonionic surfactants with the manifestation of weakly cationic properties in acidic media. It is a product of OJSC NPP Research Institute of Surfactants Volgodonsk. TU 2482-007-04706205-2006.

Physico-chemical characteristics of the stabilizer OKSIPAV-A.30 used in the work are given in table 4.

5. Emulsifier "KADEM-VT"

The KADEM-BT reagent is a mixture of alkylamidopolyamines and alkylimidazoline polyamines derived from C ₁₆ -C ₂₀ acids of plant and (or) animal origin. It is a product of OJSC NPP Research Institute of Surfactants Volgodonsk. TU 2482-009-04706205-03.

The physicochemical properties of the KADEM-VT emulsifier used in the work are given in Table 5.

6. The Portland cement used meets the requirements for cements in accordance with GOST 31108-2003 and GOST 30515-97. Table 6 shows the test results of physical and mechanical properties and the mineralogical composition of clinker of Portland cement grade M500 manufactured by CJSC Oskolcement in Stary Oskol.

7. Water for the preparation of emulsions and pre-wetting of the organomineral mixture was used with a hardness of less than 6 mg - equiv / l, which meets the requirements of GOST 23732-85 "Water for concrete and mortar".

Example. For experimental verification of the claimed composition were prepared 5 options for organomineral mixtures. As mineral materials, the above-described materials of a selected composition were used (table 1).

The preparation of bitumen emulsion was carried out in the following order. In a laboratory setup for the preparation of a bitumen emulsion, a viscous road bitumen BND 90 / was introduced at a temperature of 130-135 ° C and was added to a solution of an emulsifier with pH = 2 at a temperature of 60 ° C (water + KADEM-VT cationic reagent + OXIPAV-A.30 stabilizer). 130. The resulting bitumen emulsion belongs to slowly decaying, class EBK-3, mixes well with mineral materials of a dense grain composition.

Samples of the organomineral mixture were prepared as follows: mineral materials (crushed stone, crushing screenings, mineral powder) taken in the right ratio, cement and mineral wool (basalt fiber) were uniformly mixed in a laboratory mixer. The mixture was moistened and mixed again until a homogeneous mass was obtained, after which a bitumen emulsion was introduced. The mixture was prepared at room temperature.

From each mixture, 12 samples of organic-mineral mixtures were made on a hydraulic press. Forms for the manufacture of samples differ from those for the preparation of hot mixtures with a diameter of 70 mm, a slightly larger gap between the hollow cylinder and the liner to ensure the outflow of water during the formation of the sample. The load on the sample was gradually brought up to 40 MPa and maintained for 3 minutes.

Samples were tested after 14 days of storage in air at room temperature at a temperature of 18-20 ° C. The results of comparative tests are shown in table 7.

From the data of table 8 it follows that the organomineral mixture of the proposed composition provides an increase in the coefficient of water resistance both during ordinary tests and during prolonged water saturation, and also significantly improves strength characteristics.

table 2 Physico-mechanical properties of the sample of the original bitumen BND 90/130 No. p / p The name of indicators Norms for bitumen grade BND 90/130 in accordance with GOST 22245-90 Bitumen Sample Indicators one Needle penetration depth, 0.1 mm, at least 25 ° С 90-130 99 at 0 ° С 28 23 2 The elongation of bitumen, cm at least 25 ° С 65 one hundred at 0 ° С 4.0 4.60 3 Bitumen softening temperature, ° С, not lower 43 45 four Change in softening temperature after heating, ° C, not more than 5 four 5 Fragility temperature, ° С, not higher -17 -eighteen 6 Flash point, ° С, not lower 230 259 7 Penetration index from -1.0 to +1.0 -0.82 8 Adhesion to mineral materials of acidic rocks - 2

Table 3 Physico-mechanical properties of ultrafine basalt fiber (BSTF) No. Characteristic Norm in accordance with GOST 4640-93 Indicator value one Water resistance, pH, no more four 3.30 2 The average fiber diameter, microns from 0.5 to 3 incl. 1.20 3 The content of non-fibrous inclusions of the size of St. 0.25 mm,% by mass, not more than 5 2.20 four Density, under specific load (98 ± 1,5) Pa, kg / m ³ , no more 35 27 5 Thermal conductivity, W / (m · K), no more, at a temperature: (298 ± 5) K 0,041 0,037 6 Humidity,% by mass, no more one 0.30 7 The content of organic substances,% by weight, 2 0.45

Table 4 Physico-chemical characteristics of the reagent OKSIPAV-A.30 Name of indicator Indicator value Control method 1 Appearance at 25 ° C Transparent liquid from colorless to light yellow color without foreign matter According to paragraph 5.2 of TU 2482-007-04706205-2006 2 Mass fraction of the main substance,% 28.0-32.0 According to clause 5.3 of TU 2482-007-04706205-2006 3 Mass fraction of free amines,%, no more 0.5 According to clause 5.4 of TU 2482-007-04706205-2006 4 Mass fraction of hydrogen peroxide,%, no more 0.12 According to clause 5.5 of TU 2482-007-04706205-2006

Table 5 Physico-chemical properties of the KADEM-VT emulsifier used in the work No. p / p Name of indicator TU norm Indicator value Test method one Appearance at 20 ° C from liquid to pasty state pasty mass visually 2 Color brown brown visually 3 Amine number, mg Hcl / g, not less than 150 212.56 TU 2482-009-04706208 four Acid number mg KOH / g, not more than 10.0 5,0 GOST 22386 5 Density, g / cm ³ GOST 18995.1-73 at 20 ° C 0.940-0.960 0.951 at 50 ° C 0.935-0.955 0.940 6 Viscosity, mm ² / s (ccm), at 500 ° С, no more 600 580 GOST 33-82

Table 6 Physico-mechanical properties of Portland cement brand "M500" The name of indicators Indicator values Sieve residue 0.9 mm,% by weight 0,0 Normal density of cement paste,% by weight 25.5 The fineness of grinding (residue on a sieve of 0.08 mm),% by weight 13 Setting time, in hours: 2-25 Start 4-35 the end Withstands Volume uniformity 3.10 True density, g / cm ³ 500 Cement brand actual

The grain composition of mineral materials is presented in table No. 1.

In table 7, the content of the emulsion in the organic-mineral mixture of 11-15% is presented in the form of its component composition.

Table 8 Physico-mechanical properties of organomineral mixtures Mix No. Physico-mechanical properties of mixtures Compressive strength, MPa, at ° С Water resistance coefficient Long-term water resistance Water saturation,% by volume Swelling,% by volume twenty fifty one 2.97 0.67 0.93 0.87 1,50 0.50 2 3.52 1,52 0.89 0.80 2.80 0.80 3 3.63 1.84 0.91 0.85 3.53 1,0 four 3.05 1.45 0.86 0.83 5.27 1.10 5 1.77 0.86 0.72 0.64 7.14 1.40 Prototype 1.40-1.90 - 0.85-0.90 0.76-0.82 2.90-3.60 1.05-1.50

Claims (1)

A dense organic-mineral mixture containing mineral material - crushed granite, screening crushing, mineral powder, cement and slowly decaying class 3 cationic bitumen emulsion, including bitumen, cationic emulsifier, water, characterized in that the mixture additionally contains mineral wool - basalt fiber as part of the mineral material and the bitumen emulsion is a stabilizing additive from oxides of tertiary amines "OXIPAV-A.30" in the following ratio of components, wt.%:
mineral material 87.00-92.00 bitumen BND 90/130 3.40-5.50 water 2.30-3.70 cationic emulsifier "KADEM-VT" 0.40-0.50 OXIPAV-A.30 0.20-0.40 mineral wool - basalt fiber 0.20-0.55 cement 1,50-2,35