SU1726457A1 - Method of preparing concrete mix - Google Patents

Abstract

The invention relates to methods for the preparation of fine-grained concrete mixtures and mixtures with coarse aggregate and can be used in the building materials industry in the manufacture of reinforced concrete products and structures. The goal is to increase the strength of concrete. Activation of particles is carried out in two stages, the first of which is activated in the opposing flow into the treadmill, mineral additives with a part of the fine aggregate at the speed of particles in the flow of 40-50 m / s fine aggregate at a speed of flight of particles in a stream of 23-30 m / s with humidification. 1 tab., 1 Il.

Description

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WITH

The invention relates to methods for the preparation of fine-grained concrete mixtures and mixtures using coarse aggregates and may find application in the building materials industry in the manufacture of reinforced concrete products and structures.

The purpose of the invention is to increase the strength of concrete.

An example: A mineral blended into a batch, mineral additives and 20% by weight of a fine-grained aggregate with natural moisture are fed to the receiving bin of the mixer -activator of the first activation stage I (see drawing). In the second receiving hopper installed at the opposite end of the mixer activator 1, 80% of the building sand is metered by weight to the batch. From the receiving hoppers of the mixer-activator 1, the dosed components under their own gravity force are fed to the rubberized blades of the rotor of the mixer-activator with a diameter of 300 mm rotating at 3000 rpm and acquire a circumferential speed of 40-50 m / s. The blades in the amount of 72 pieces are installed along a two-run screw generatrix at an angle of 27-30 ° to the rotor axis. The particles of the mixture, having received the initial velocity from the front side of the first row of blades, change the direction of their flight at a certain angle corresponding to the angle of installation on the axis of the blades. Striking the back side of the next row of blades and reflecting from them change the direction of their flight. On the other hand, the front side of the blades of the second row also informs the particles of the mixture at a speed of 40-50 m / s at an angle to the direction of movement of the flow of particles,

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razhennogo from the back of the blades of the second row yes. When these two streams of particles meet in the space between the rows of blades, the particles are activated due to their collision, friction against each other, which leads to the destruction of not only the aggregates formed from individual particles, but also the particles themselves due to defects in their structure, as well as their surfaces.

As a result of carrying out the first stage of activation of the mineral into the emulsifying, active mineral additives with a part of the fine aggregate, the mixed mineral is obtained into the emulsion with the activated particles.

When the shaft rotates with blades mounted on it (rotor), a vortex airflow is created in the activator mixer, which moves the activated mixed into the activator mixed along the length of the mixer and sends it through the discharge nozzle to another consistently installed mixer activator 2 with a diameter of 600 mm . At the unloading nozzle of the mixer-activator, the mixed substance is pre-mixed with incoming continuous flow from the bunker with building sand with natural moisture, and this mixture enters the mixer-activator 2, Repeated stage of activation of particles mixed with the remaining (80%) fine aggregate wire t also in the opposite flows at a speed of particles in them of 23-30 m / s.

When the rotation speed of the rotor of the mixer -activator 2 is 1000 rpm, the circumferential speed of rotation of the blades is 31.8 m / s, which provides high-quality activation of particles of building sand and uniform distribution of the mixed into a slurry in the mixture.

At the outlet of the mixer -activator 2, the mixture is humidified and heated.

the liquid phase is pumped through the nozzles by the hydraulic system 3. The wetted mixture (mortar) is fed into the mixer 4 with forced mixing.

The air captured by the blades of the mixer-activators of the first and second stages, freed from dust by moistening, flows through the branch pipe of the expansion chamber of the mixer-activator 2 into the

the atmosphere.

In the concrete mixer 4, coarse aggregate is metered with natural moisture and mixed with the mortar, the solid phase of which was activated in the mixer x-activators of the first and second activation stages. If necessary, the mixture in the concrete mixer is additionally humidified and heated with steam. The prepared concrete mix is served in

feed bin 5 for later use.

Claims (1)

The invention The method of preparation of concrete mixture, including mixing and activation in a high-speed mixer of portland cement, an active mineral additive, part of a fine aggregate and an aqueous solution of a plasticizer, the subsequent mixing of the resulting mixed into a slurry with the rest of the fine aggregate, coarse aggregate and water in a concrete mixer, which is characterized by the fact that, in order to increase the strength of concrete, mixing and activation in a high speed mixer carried out using 20% of the fine aggregate in the opposite flows at a particle velocity in the flow of 40-50 m / s, then the rest of the fine aggregate is introduced into the mixed host and re-activated at a particle velocity in the flow of 23-30 m / s after which the mixture is moistened and finally mixed with coarse aggregate in a concrete mixer. In concrete, on slag cement in granular instead of cement, granulated blast furnace slag was used, ground to a specific surface of 5000 cm2 / g, and instead of water, a solution of liquid glass of a basicity module 1.8 and a density of 1.25 g / cm3. 25