SU392032A1 - INVENTIONS - Google Patents

Description

one

The present invention relates to the field of building materials and products.

Raw mixes for the manufacture of lightweight concrete are known, including expanded clay gravel, portland cement, water and limestone.

However, the existing claydite compositions do not have the structure necessary to produce exterior wall panels with a reduced bulk weight and clay consumption and with a stable porous part of the structure.

The purpose of the invention is to increase the stability and volume of pore formation and to obtain a continuous non-separable concrete structure.

This is achieved by the fact that the concrete mixture contains as a limestone component a product of crushing a low-strength shellfish: 70-95% with a specific surface of grains of 60-200 and 5-30% with a specific surface of grains of 400-3000 cm- / g and, moreover, air entraining additive in the amount of 0.01 - 0.3% of the weight of the binder.

The composition of the light concrete mixture contains 25–40% expanded clay gravel, 20–25% cement, ent,. 12-16% of water, 15-35% of limestone, air-entraining; th .-- (GH.B, DNIPS-1) and plasticizing (PRS) additive. :.

The novelty of the composition is - the introduction., Jointly air-entraining additive and the product of crushing the low-line shellfish instead of expanded clay sand; 70-95% of fine-grained grains with a specific surface of 100-130, and 5-30% of particles with a specific pore surface of 400-1000. At the same time, the shell sand of fraction O-10 mm has a strength in the range of 30-70 kg / cm, and the resulting structure provides for the manufacture of unstrivable expanded clay and shell concrete with

the bulk weight of 1000-130 0 kg / m brands 50, 75, 100, 150.

The peculiarity of the introduction of rough grains of shell sand lies in the double effect on pore formation: relatively large particles with a specific surface area of 100 cm-1g contribute to an increase in the amount of air entraining, while small particles with a specific surface area of 400 cm- / g increase ycToi i4HBocTb "provide the formed pores with cement -rakushechnom veil. The roughness of shells particles, which provides a more developed surface of contact with the gas and cement components, plays an important role in creating a finely porous structure. - - Test experiments were carried out with the use of additives SST (0.1%) and PRS

. {0.1%); - and the ratio of cement: shell

sand + boda, p-auggem -1 v 1-4-4 t-0.7, which corresponded to the proposed composition (its porous solution part). The results of testing the proposed and comparative compositions, including in panels with a bulk weight of 1000-1300 kg / m, confirm the positive effect obtained using the proposed composition. The volume of entrained air is increased by 15%, and the volume weight of the cement-shell porous dough is reduced to 0.8-0.85 g / cm. With a bulk weight of expanded clay gravel in cement dough equal to 0.8-0.9 kg / m, a continuous non-stratifiable structure is created, having a similar or equal bulk weight and, accordingly, the insulating capacity of the parts. Positive features of the composition are also reduced consumption of expanded clay gravel, the use of complex additives.

economic efficiency, expansion of the raw material base of large-panel housing construction.

Subject invention

Raw mix for making lightweight concrete, which includes expanded clay gravel, portland cement, water and limestone component, characterized in that, in order to increase the stability of the pore formation volume and to obtain a continuous non-separable concrete structure, it contains the product of crushing low-shell rock as a limestone component : 7Q-95% with a specific surface area of grains of 60–200 and 5–30% with a specific surface area of grains of 400–3000 and, in addition, an air-entraining additive in an amount of 0.01–0.3% of the weight of the binder.