EA002877B1 - Method for repairing concrete layer on roads and bridges - Google Patents

Abstract

A method for repairing a concrete layer on roads and bridges, comprising arranging a membrane of polymeric and bitumen binder on said layer, placing asphalt concrete on said membrane and rolling it, characterized in that prior to the membrane arrangement the concrete is impregnated with a compound having the following component ratio, wt %: sodium hydroxide 2,0-3,0 phosphoric acid 3,5-4,5 sodium carbonate 0,8-1,2 water remaining the consumption of said compound is 0.35-0.55 kg per 1m<2> of a concrete layer, wherein the consumption of the polymeric and bitumen binder in the membrane is 2.9-3.5 kg per 1 m<2> of a concrete layer and asphalt concrete is placed with residual porosity within 6-10%.

Description

The invention relates to the maintenance of roads, in particular to the repair of concrete pavements on roads and bridge deck.

A known method of repairing an old concrete pavement, including a device on a concrete of a polymer-bitumen binder membrane on concrete, and applying a thin layer of asphalt concrete to the seal on the membrane [1].

The disadvantage of this method is the weak adhesion of the membrane with a layer of concrete and high permeability of the concrete layer.

The problem solved by the claimed invention is to increase the adhesive properties of the membrane to the surface of the concrete, as well as to ensure reliable waterproofing properties of the repaired structure.

The task is solved in such a way that in the method of repairing the concrete layer, which includes the device of a polymer-bitumen binder membrane on it, applying a layer of asphalt concrete and compaction to the membrane, before the device of the membrane is impregnated with the composition, the Sling with the following ratio of components, wt.%:

Sodium hydroxide 2.0-3.0

Phosphoric acid 3.5-4.5

Sodium carbonate 0.8-1.2

Water Else and with a consumption of impregnating composition of 0.35-0.55 kg per 1 m ^{2 of} concrete layer, while the membrane is arranged with a consumption of polymer-bitumen binder 2.9-3.5 kg per 1 m ² , and asphalt concrete is laid with residual porosity of 6-10%.

The inventive method is as follows.

The old concrete coating on the road or concrete protective layer on the bridge deck is impregnated with the Sling composition, including sodium hydroxide (IOH), phosphoric acid (H ₃ PO ₄ ), sodium carbonate (Ia ₂ CO ₃ ) and water. The consumption of the impregnating composition is 0.35-0.55 kg / m ² . After the moisture dries, a membrane of polymer-bitumen binder is laid on the concrete surface at a temperature of 170-180 ° C. The consumption of a polymer bitumen binder, consisting, for example, of a mixture of bitumen with a styrene-styrene-styrene group, is 2.9-3.5 kg / m ² . After filling the membrane, crushed stone is distributed and asphalt concrete with a residual porosity of 61–0% is laid with a known paver. Compaction of the coating is carried out using known means.

Examples of specific performance are given in table. 1 and 2.

Capillary suction of water is determined on samples-cubes of concrete measuring 7x7x7 cm. Samples were treated with impregnating compositions with the indicated flow rate so that one end surface remained untreated. After 28 days of storage under normal conditions, the samples were placed in a bath with an unprotected surface up and filled with water in such an amount that the bottom end face was immersed in water by 1 cm. Weighing the samples determined their masses after 48 hours. To determine the adhesion, the samples were applied to the treated surface polymer bitumen membrane with a flow rate of 3.2 kg / m ² and a layer of asphalt concrete, after which the applied layer was knocked down to complete separation. From the table. 1, 2 data, it follows that the optimal impregnating composition Sling has the following ratio of components, wt.%:

Sodium hydroxide 2.0-3.0

Phosphoric acid 3.5-4.5

Sodium carbonate 0.8-1.2

Water Rest

Table 1

No. p / p Impregnating composition Consumption impregnating composition, kg / m ² Capillary absorption of water, g Adhesive grip, number of strokes Sodium hydroxide, wt.% Phosphoric acid, wt.%. Carbonic sodium, wt.%. Water, wt.%. one 1.5 4.0 1.0 93.5 0.45 22.6 four 2 2.0 4.0 1.0 93.0 0.45 14.1 five 3 2.5 4.0 1.0 92.5 0.45 7.3 eleven four 3.0 4.0 1.0 92.0 0.45 12.7 6 five 3.5 4.0 1.0 91.5 0.45 19.4 3 6 2.5 3.0 1.0 93.5 0.45 19.9 four 7 2.5 3.5 1.0 93.0 0.45 12.9 eight eight 2.5 4.5 1.0 92.0 0.45 12.2 9 9 2.5 5.0 1.0 91.5 0.45 18.9 7 ten 2.5 4.0 0.6 92.9 0.45 19.4 four eleven 2.5 4.0 0.8 92.7 0.45 13.0 9 12 2.5 4.0 1.2 92.3 0.45 11.1 ten 13 2.5 4.0 1.4 92.1 0.45 20.2 6 14 2.5 4.0 1.0 92.5 0.30 22.1 3 15 2.5 4.0 1.0 92.5 0.35 15.1 eight sixteen 2.5 4.0 1.0 92.5 0.55 6.5 12 17 2.5 4.0 1.0 92.5 0.60 6.5 12

table 2

The test results of the repaired protective waterproofing layer

Polymer-bitumen binder consumption for membrane, kg / m ² Residual porosity % Water resistant Durability at 50 ° C, MPa The time of action of water under pressure of 0.5 MPa, min Presence of water Magnitude Standardized by STB 1033-96 2.8 11.8 thirty there is 1.4 not less than 1.1 2.9 9.8 thirty not 1.4 also 3.2 8.2 thirty not 1.2 n 3.5 6.4 thirty not 1.1 P 3.7 4.8 thirty not 0.6 P 3.2 eleven thirty there is 1.2 P 3.2 ten thirty not 1.2 P 3.2 6 thirty not 1.1 P 3.2 four thirty not 0.9 P

The deviation of consumption of polymer-bitumen binder for the above limit values leads (see Tables 1, 2) to an increase in capillary suction and a decrease in adhesive adhesion of concrete to the polymer-bitumen membrane. An increase in consumption above 0.55 kg / m ² does not give an additional positive effect.

Waterproofing properties of the repaired structure were determined by the indicator of water resistance (STB 1033-96, GOST 2678-94). The tests were carried out on samples including a layer of concrete, a membrane and a layer of asphalt concrete, the total size of the samples [(150x150) ± 1] mm. In the working chamber of the device for testing was established between the rubber pads sample. A contact grid was placed on the sample, covered with a plate and tightly pressed with screws. An excess hydrostatic pressure of 0.5 MPa was created in the working chamber, the sample was kept for 30 minutes. A sample is considered to have passed the test if no water appears on its surface for a specified time at a given pressure.

From the data table. 2, it follows that water permeability is ensured if the amount of the polymer-bitumen binder, which the membrane consists of, exceeds 2.9 kg / m ² . With an increase in the amount of binder more than 3.5 kg / m ^2, it penetrates into the pores of asphalt concrete in an excess amount and reduces its strength at a temperature of 50 ° C below the normative limit.

The residual porosity of asphalt concrete 610% provides the required waterproofing properties of the repaired layer.

The claimed invention has advantages compared with the known:

1. Improves the adhesive bond on the contact of the concrete layer with the membrane.

2. Improves waterproofing properties.

3. Increases the economic efficiency of waterproofing works in the repair of the bridge deck by eliminating the work of replacing the old waterproofing.

A source of information

1. Article 4th European Symposium on Bitumen and Asphalt Concrete. Journal of Roads No. 8, 1990, p. 15-16.

Claims (1)

CLAIM The method of repairing the concrete layer on roads and bridges, including the device on it of a polymer-bitumen binder membrane, applying asphalt concrete to the membrane and compaction, characterized in that the concrete is impregnated with the composition before the membrane device in the following ratio of components, wt.%: Sodium hydroxide 2.0-3.0 Phosphoric acid 3.5-4.5 Sodium carbonate 0.8-1.2 Water Rest and with a consumption of this composition 0.35-0.55 kg per 1 m ^{2 of} concrete layer, while the membrane is arranged with a consumption of polymer-bitumen binder 2.93.5 kg per 1 m ^{2 of} concrete layer, and asphalt concrete is laid with residual porosity 6 -ten%.