SU990745A1 - Method for curing fresh-placed concrete - Google Patents

Description

(5) SPOOL CARE FOR FRESHLY DESIGNED

one

The invention relates to the construction and can be used in the care of concrete at a construction site, mainly when exposed to linear structures.

A known method of caring for concrete is based on the use of finished polymer films laid on the surface of the concrete to preserve the mixing water 1 therein.

However, with this method of care, polymer films have a relatively small weight per unit area. In the wind- During heavy weather when large areas, such as road, airfield and other coatings, are used, polymer films are difficult to lay on the concrete surface due to the aerodynamic effect. Therefore, additional measures are needed to fix polymer films on a significant basis, especially when operating highly mechanized and high-performance complexes. CONCRETE

The closest in technical essence to the present invention is a method of caring for freshly laid concrete by applying a mixture of distilled naphthenic acid on its surface and adding and treating the resulting layer with mineral binder 2 J

Distilled naphthenic acid with 1-2 chromic anhydride is applied to fresh concrete.

10 in the form of a 50% aqueous solution, and then lime is sprayed to remove the tackiness of the waterproofing layer and harden the naphthenic acid.

However, the known method does not allow to obtain concrete with high strength and crack resistance.

The purpose of the invention is to increase the strength and crack resistance of concrete.

This goal is achieved by

20 that according to the method of caring for freshly laid concrete by applying a mixture of distilled naphthenic acid with an additive and treating the resulting layer with mineral adhering on its surface, a mixture of distilled naphthenic acid with a suspension of ore powder in the ratio O, 01: 1 is applied to the surface of the concrete (0,), and the semi-valuable layer is treated with a 50-b7% aqueous solution of liquid glass. The method is carried out as follows. After laying the concrete mix and finishing the surface, apply sprayed naphthenic acid and alumina powder suspension by spraying onto fresh concrete with distributor machines or manually and maintain the concrete until the desired strength is reached. At the same time, a suspension of aluminum powder and distilled naphthenic acid in a ratio of 0.01: -1, applied to the surface of freshly laid concrete, reduces the theomic stresses in the surface layer and polymerizes it. At the same time, the freshly laid concrete is being cared for and its surface layer is hydrophosed at the stage of formation of cement stone. Distilled naphthenic acid under the influence of environmental conditions does not form a solid film on the surface of the concrete, remaining in a liquid form. It is impossible to operate extended structures, such as roads, airfields, due to strong slip. For curing the suspension of aluminum powder and distilled naphthenic acid at the age of 1-28 days, the surface of the concrete is additionally treated with an aqueous solution of water glass in a 1: 1 ratio. Aqueous liquid glass solution enhances the waterproofing properties of the protective coating. As a result of the treatment of concrete with a solution, its resistance to the negative effects of the conditions of a dry hot climate is increased. The use of aluminum powder and distilled naphthenic acid in the ratio of Co, 01: 1) - (, 0, and the subsequent curing of concrete with a solution of water glass with a ratio of 1: 1-1: 0.5 as a combined method of hydro-oxidation and silication of concrete at the stage of its hardening, allows to obtain concrete structures that are durable in operation in a dry hot climate. The coefficient of crack resistance, as the most characteristic indicator of the durability of a structure that is operated under alternating rates The temperature determined by the MIIT method is equal to 0.81, which significantly exceeds the properties of concrete obtained under standard conditions of its hardening. Aluminum powder in the amount of 0.01-0.04 by weight of distilled naphthenic acid allows to obtain the reflection coefficient of the resulting layer 0, 6. A decrease in the amount of aluminum oxide impairs the optical characteristics of the suspension, and an increase does not affect this characteristic, but reduces the viscosity of the composition. The suspension of aluminum powder and distilled naphthenic acid in the ratio (O, 01: 1) -10,) is optimal, is technologically advanced in many parameters, improves the properties of concrete, creates a favorable temperature and humidity regime for hardening concrete. Curing of this suspension occurs at the optimum concentration in an aqueous solution of liquid glass - 50-67. Increasing the amount of liquid glass causes coagulation of naphthenic acid, rather than curing it, exceeding the specified amount of water delays the hardening of aluminum powder formed from the suspension and DNA on the concrete surface of the film. Care of fresh concrete is carried out as follows. As a material for protecting the concrete surface, a mixture of aluminum powder and distilled naphthenic acid is applied to newly formed samples in a ratio of 0.03: 1, which is then cured at 1-day age of concrete hardening with an aqueous solution of liquid glass. Distilled naphthenic acid is also applied with the addition of a 50% aqueous solution of chromic anhydride in an amount of 2% pure SG20 based on the weight of naphthenic acid, followed by lime spraying. Concrete samples (beams with a size of 10 X 10 X 0 cm), on which the concrete's flexural strength is determined, and the compressive strength at their ends, are placed in a climatic chamber, where conditions of a dry hot climate are simulated. Concrete standards of standard curing in a normal curing chamber are taken as a standard.

59907 56

The results of the tests are presented by laid concrete with a suspension of aluminum in the table. Evoy powder and distilled naphtha. Thus, physicomechanical acid followed by hardening properties and durability of the concrete end is enhanced by a solution of water glass with corrosion protection when freshly protected.

Concrete curing methods

be

Strength

Coffina concrete with flexural curvature, crack resistance MPa (according to the MIIT method)

Treatment of fresh concrete with aluminum powder suspension and distilled naphthenic acid, followed by curing it with a solution of liquid glass with water

Protection of hardening concrete with naphthenic acid with the addition of an aqueous solution of chromic anhydride followed by application. Formula of the invention. Method of care for fresh concrete by applying a mixture of distilled naphthenic acid with an added mineral on the surface and treating it with a mineral layer, which is crack resistance of concrete, a mixture of distilled naphthenic-45th acid with aluminum suspension is applied to the surface

0.81

5.2

32.7

powder in the ratio (O, 01: 1) - (0.04: 1) and the resulting layer is treated with a 30-7% aqueous solution of liquid glass.

Sources of information taken into account in the examination

1. Author's testimony of the USSR N-, cl. C O B ifl / BO, 1958.

2, USSR Copyright Certificate No. 29 27 8 / 29-33,

cl. C 04 B 1/30, 12.05.80,

Claims (1)

Claim A method of caring for freshly laid concrete by applying to its surface a mixture of distilled naphthenic acid with an additive and treating the precoated layer with a mineral binder, characterized in that, in order to increase the strength and crack resistance of concrete, a mixture of distilled naphthenic 45 acid with a suspension of aluminum is applied to the surface powders in the ratio (0.01: 1) to (0.04: 1) and the resulting layer is treated with a 5067% aqueous solution of water glass.