EA038568B1 - Bitumen-concrete mix - Google Patents

Abstract

The invention relates to the field of construction materials, in particular, to road construction materials containing organic binder, and can be used for the preparation of bitumen-concrete mixes used for pavements of III-IV category motor roads in climatic areas I-IV, and for floors in service premises. The bitumen-concrete mix contains, wt.%: sand (natural or screened crushed rock) - 30.0-52.5; bitumen - 3.5-9.0; mineral powder - 1-8.5; wastes of built-in bituminous roofing, crushed 5 to 15 mm, containing 20 to 80% of viscous bitumen - 1-30; crushed stone - the balance. Roofing felt is used as wastes of built-in bituminous roofing. The proposed solid bitumen-concrete mix features enhanced physical and mechanical characteristics, lower prime cost due to a high rate of use of wastes of built-in bituminous roofing, the recycling of which contributes to the mitigation of environmental damage.

Description

The invention relates to the field of building materials, in particular building road materials containing an organic binder, and can be used in the preparation of asphalt concrete mixtures used for the construction of road surfaces of III-IV categories in

I-IV climatic zones, as well as floors in office premises.

Known asphalt mixture containing crushed stone, sand, mineral powder and bitumen binder from the waste of repair of soft roofs, plasticized with rectangular tar (1).

The disadvantage of the known asphalt concrete mixture is its low physical and mechanical characteristics, the method of producing the asphalt concrete mixture is complex, lengthy and costly.

The closest to the proposed asphalt concrete mixture is an asphalt mixture containing, wt%: crushed stone - 38-50, bitumen - 4-6, mineral powder - 7-20, soft roof waste, crushed to 5 mm, containing from 75 to 80% viscous bitumen - 1.5-3.0, sand - the rest (2).

The disadvantage of this invention is low physical and mechanical properties with a minimum reduction in environmental damage due to the disposal of roofing waste.

The objective of the claimed invention is to obtain a dense asphalt concrete mixture with improved physical and mechanical characteristics and a lower cost due to a higher percentage of use of soft roof repair waste, the utilization of which greatly contributes to the reduction of environmental damage.

The problem is solved by using the proposed asphalt concrete mixture containing, wt%: sand (natural or screening of crushing rocks) - 30.0-52.5, bitumen - 3.5-9.0, mineral powder - 1-8 , 5, soft roof repair waste, crushed from 5 to 15 mm, containing from 20 to 80% viscous bitumen - 1-30, crushed stone - the rest.

Waste roofing material is used.

The granulometric composition of the mineral part (non-combustible residue) of the waste of the soft roof is as follows:

Fraction, mm 1.25 0.63 0.315 0.16 0.071 <0.071 Parts, remainder,% 0-4 3-11 29-37 19-27 7-18 18-26

A feature of the proposed asphalt concrete mixture is the introduction into its composition from 1 to 30 wt.% Of crushed from 5 to 15 mm wastes of a soft roof, containing from 20 to 80% of viscous bitumen, which determines the percentage of its constituent components. At the same time, such physical and mechanical properties of the presented asphalt concrete mixture, such as compressive strength, increase.

By reducing the content of mineral powder, as well as increasing the percentage of use of waste from repair of a soft roof, the cost of the proposed asphalt concrete mixture is reduced, which makes it possible to dispose of a large amount of waste from repair of a soft roof, which, in turn, reduces the damage to the environment.

Shredding of wastes from repairing soft roofs to the specified sizes can be carried out in an electromechanical crushing plant of the MD BKM type with a capacity of 450 kg / h, manufactured by RABIKA LLC, Naberezhnye Chelny.

The crushing plant contains a chamber with a rotor with steel knives, equipped with a receiving and unloading hopper and a rotary sieve with cells from 6 to 10 mm.

Pieces of soft roof repair waste, 40x100 mm roofing material, pre-cut with a guillotine, are loaded by 10-15 kg through the receiving hopper into the chamber, where the soft roof repair waste is crushed and the construction bitumen is separated from the cardboard base. Through the unloading hopper, the crushed waste from the repair of the soft roof is directed to a rotary sieve to separate the bitumen powder from the cardboard. Bituminous crumbs spilled through the cells are packed into bags and sent for further use. A separate technological line prepares the initial components, where crushed stone, sand, mineral powder are heated to 170 ° C and mixed, then cold bitumen chips obtained as a result of crushing the soft roof waste are fed and mixed for 3-5 minutes. Then bitumen is added and further mixing of the entire mass occurs until lumpiness and heterogeneity are removed. The resulting asphalt concrete mixture is unloaded into dump trucks to be sent to the site.

Were made five model compositions of the proposed dense asphalt mixture (see compositions in table. 1).

The advantages of the proposed asphalt mixture are shown in table. 2.

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Compositions of asphalt concrete mixtures

Table 1

Components used COMPOSITION # 1 # 2 No. 3 # 4 # 5 Sand (natural or screening of crushing rocks) 25 thirty 45 50 55 Bitumen 2.0 3.5 5 eight ten Mineral powder 0.5 1.0 5.0 5.0 5.0 Waste from the repair of a soft roof, crushed from 5 to 15 mm, containing from 20 to 80% viscous bitumen 0.5 1.0 15.0 24.0 30.0 Crushed stone 72 64.5 23.0 13.0 -

Test results of asphalt concrete mixtures

table 2

P / p No. Physical and mechanical indications patent No. 2323909 composition No. 1 composition No. 2 composition No. 3 composition No. 4 composition No. 5 1 Water saturation% by volume 2.6 2.7 2.9 3.7 4.0 5.2 2 Compressive strength at 50 ° C 1.9 1.9 2.0 3.9 4.0 3.0 3 Compressive strength at 20 ° C 5.3 5.4 5.4 6.2 6,7 5.3 4 Compressive strength at 0 ° C 10.8 10.9 10.9 17.9 18.1 15.1 5 Water resistance coefficient 0.98 0.97 0.97 0.95 0.94 0.93

As you can see from the table. 2 given in the claims, the composition of the asphalt mixture has increased compressive strength.

Sources of information:

1. Patent RU No. 2500635

2. Patent RU No. 2323909

Claims (2)

CLAIM 1. An asphalt concrete mixture containing sand, bitumen, mineral powder, crushed stone and crushed waste from the repair of a soft roof containing viscous bitumen, characterized in that the waste of a soft roof is crushed from 5 to 15 mm and contains from 20 to 80% of viscous bitumen, with the following content of components, wt.%: sand (natural or screening of crushing rocks) - 30.0-52.5, bitumen - 3.5-9.0, mineral powder - 1-8.5, soft roof repair waste, crushed from 5 to 15 mm, containing from 20 to 80% of viscous bitumen - 1-30, crushed stone - the rest. 2. The asphalt-concrete mixture according to claim 1, characterized in that roofing material is used as a soft roof waste.