SU1660965A1 - Method of manufacture prefabricated cellular concrete products - Google Patents

Abstract

This invention relates to the manufacture of cellular concrete products and structures. The purpose of the invention is to reduce the process and increase the strength of the products. In the manufacture of cellular products, a cellular concrete mixture is poured into the form, a dry cement-sand mixture is applied to the surface of the mixture, then a cover is placed on the mold, vibration is carried out for 2–3 seconds, the cover is firmly fixed and the heat-moisture treatment is carried out remove the cover and disassemble the products. 1 tab.

Description

The invention relates to the building materials industry and can be used in the manufacture of cellular concrete products and structures.

The purpose of the invention is to reduce the process and increase the strength of the products.

In the manufacture of cellular products, a cellular concrete mixture is poured into the form, a dry cement-sand mixture is applied to the surface of the mixture, then a cover is installed on the mold, vibration is carried out for 2-3 seconds, the cover is rigidly fixed and heat-moisture treatment is performed dismantling and removing the cover. Pigment and hydrophobic additives can be added to the dry cement / sand mixture.

The method is carried out as follows.

The studies were carried out on the original cement: fly ash 1: 2 with B / T 0.47.

A cleating agent is used as a pore-forming agent. - Foam-concrete mixture of the indicated composition is prepared in a forced-action mixer. Forming is carried out by injection molding. Samples are made in the forms of two series, both with and without applying this layer on the open surface of the newly-formed concrete with a cement-sand mixture with a layer of 7-10 mm. The molded samples are covered with a lid, ensuring contact over the entire surface of the mixture and rigidly attached to the sides of the molds. Samples coated with a cement-sand mixture vibrate for 2-3 seconds on a vibrating plate with a lid, after which the lid is rigidly attached to the sides of the mold. With vibration, the cover adheres to the sides of the mold, with a longer time of vibration, a gap is formed between the settled concrete mass and the cover. Heat protection

ABOUT

u o ate

to

Newly molded samples were processed at an isothermal holding temperature of 96 ° C in a steaming chamber at 4 + 6 + 2 h, as were the prototype samples. After demolding all the samples are dried to constant weight at 105-110 ° C, then their physicomechanical properties are determined.

The results obtained are presented in the table.

As can be seen from the table, the optimal pre-exposure time of the cheeto-concrete samples at an air temperature of 18-20 ° C is 16-20 hours. The heat and moisture treatment is 12 hours. The total duration of the manufacturing process is 30 hours. For the production of similar samples the proposed method requires only 12 hours, while they have a durability

Compression is higher by 11-20% compared with samples made in a known manner.

FORUMAWLAH AND ISLANDS

A method of manufacturing cellular concrete products, including pouring a concrete mixture into the form of a concrete mixture, applying a layer of dry cement-sand mixture to the surface,

vibration and subsequent warm-moisture treatment and demoulding, characterized in that, in order to reduce the process and increase the strength of the products, a dry cement-sand mixture is applied to a freshly formed open surface, then a cover is placed on the mold and the vibration is carried out for 2- 3 seconds, after which the lid is firmly fixed, which is removed during demoulding.

Note. Average density is 800 kg / m

Claims (1)

Claim A method of manufacturing aerated concrete products, including pouring in the form of a cellular concrete mixture, applying a layer of dry cement-sand mixture to the surface, vibration and subsequent heat-moisture treatment and stripping ⁷ , characterized in that, in order to reduce the process and increase the strength of the products, dry cement-sand the mixture is applied to a freshly formed open surface, then the lid is mounted on the mold and vibrated for 2-3 s, after which the lid is rigidly fixed, which is removed during formwork. Sample ' Pre-exposure time _x hours Plastic strength, gf / cm ² Compressive Strength, MPa (%) The result of external inspection of samples after heat and moisture treatment Prototype 8 100 3.6 On the side surfaces 12 150 4.0 samples are observed microcracks 16 230 4.3 The side surfaces are 20 310 4.4 (100) without microtrack 24 400 4.4 (100) Surface samples layer of cement / sand mixture - - 5.3 (120.4) Also ) Samples do not have single layer cement sand mixture 4.9 (111.4) tt ¹ Note. The average density is 800 kg / m ³ . Compiled by V. Lebedev Editor A. Motyl Tehred M. Morgenthal Corrector O. Kravtsova Order 2085 Circulation 384 Subscription VNIIIPI of the State Committee for Inventions and Discoveries at the State Committee for Science and Technology 113035, Moscow, Zh-35, Raushskaya nab., 4/5 Production and Publishing Combine Patent, Uzhgorod, 101 Gagarin St.