SU916632A1 - COMPOSITION FOR ROAD EQUIPMENT AND COATING 1 - Google Patents

Description

The invention relates to construction materials, namely to compositions used in the construction of highways.

A composition [1] for the construction of a road base and surface is known, comprising, by weight %:

Waste blast furnace slag 73.0

Cement dust 15.0

Water 12.0

The closest to the invention in technical essence and the achieved result is the composition [2] for the construction of a road base and surface, including, in wt. %:

Soil 57-70

Ground burnt rock I-19

Cement dust 4-6

Lime 4-6

Calcium chloride 1-2

Water is the rest.

However, road bases and surfaces made from known compositions are not strong enough.

The purpose of the invention is to increase the strength of the road base and surface.

2

The stated objective is achieved by the fact that the composition for the construction of a road base and surface, including ground burnt rock, cement dust, filler, inorganic acid salt and water, contains blast furnace slag as a filler and calcium nitrate as an inorganic acid salt in the following ratio of components, wt. %:

Ground burnt rock 10-20

Cement dust 10-20

Waste blast furnace slag 43.0-71.5

Calcium nitrate 1-2

Water is the rest.

Ground burnt rock is a dehydrated clay mineral with a specific surface after grinding of 300-5000 ^cm2 /g, chemical composition, wt.%: _S02 55.0%; _{Al2O3 26.8} ; _{Br2O3 8.4} ; the rest 9.8.

Waste blast furnace slag has the following chemical composition, wt. %: SiO ₂ 36.75; Al ₂ O 2 9.5; CaO 49.5; MgO 3.0; Fe ₂ O 3 0.5; MnO 0.5; balance 0.25.

Cement dust, ordinary waste, chemical composition, wt.%: 5Ю ₂ 19.1;

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A1 ₂ 0з 4.8; Bg ₂ O ₃ 3.2; CaO 50.4; 2.4;

5O ₃ 5.4; P ₂ O 5.9; the rest 10.8.

Specific examples of implementation are given in Table 1.

Comparative physical and mechanical properties of samples prepared from the proposed and known compositions are given in Table 2.

The increase in the strength properties of samples prepared from the proposed composition is ensured by the fact that ground burnt rock, due to its chemical composition, reacts with lime released during the hydration hardening of waste blast furnace slag and cement dust, with the formation of soluble compounds with binding properties.

However, effective interaction of lime, silica and alumina is possible only with a high degree of amorphization of SiO ₂ and Al ₂ O ₃ , and a sufficient concentration

calcium hydroxide released into the solution during hydration of slag binder and cement dust.

Calcium nitrate, which includes nitrite and nitrate calcium salts, ensures that the reaction of the active components of slag, cement dust and ground burnt rock proceeds at a sufficiently high rate, since it is both an activator of the hardening of waste blast-furnace slag and a cation-active substance that amorphizes the siliceous and aluminous components of ground burnt rock.

The technology for constructing a road base and surface from the proposed composition does not change in comparison with the generally accepted one and includes dosing and mixing of all components, moistening to optimal moisture content and compaction.

The proposed composition can be used for the construction of foundations and surfaces of roads of technical categories P-U.

Table 1

Composition Content in the mixture, wt.% Blast-furnace slag Cement dust Ground burnt rock Lime Grunt Chlorine Calcium Calcium nitrate Water Proposed 1 70 10.0 10.0 - - - 1.0 9.0 2 56.5 15.0 15.0 - - - 1.5 15.0 3 43.0 20.0 20.0 - - - 2.0 12.0 Famous - 5.0 15.0 5.0 63.0 1.5 - 10.5 T a b l and ts a 2

Famous

Composition

Proposed

1

2

3

Ultimate strength, MPa water-saturated samples Indicator When compressed At bending increasing deformation resistance Duration of hardening, day 60 | 120 60 | 120 9.4 14.6 0.9 2.05 0.22 10.2 15.2 1.3 2.6 0.26 10.4 15.8 1.15 2.6 0.27 4.8 6.5 1.2 1.5 0.18

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Claims (1)

Claim Composition for the device of the road base and coating, including ground burnt rock, cement dust, for-; fillers, an inorganic acid salt and water, characterized in that, in order to increase strength, it contains as filler depleted blast furnace slag, and as the inorganic acid salt - calcium nitrate at ele- ¹ ® blowing ratio, May. %: 6 Ground burnt rock 10-20 Cement dust Yu — 20 Waste blast-furnace slag 43.0–71.5 Calcium nitrate 1-2 Water Else.