SU1463486A1 - Method of moulding articles from hard concrete mix - Google Patents

Abstract

The invention relates to the building materials industry in the manufacture of products from rigid concrete mixtures. The purpose of the invention is to improve the quality of long products by hardening the surface layer and providing strict geometrical dimensions, simplifying stripping and reducing material consumption. The shape of the vibropress is set on a vibrating plate, rotating with the hay, so that the angle between the axis of the mold and the direction of application of the sealing load is 1.5-4.5 °. The vertical compaction load is created by the punch. At the same time, vibration oscillations are applied to the form along the y-dense load: a frequency of 50 Hz and an amplitude of 0.9-1.5 mm. 2 tab., 2 Il. i (L

Description

one

The invention relates to the building materials industry in the manufacture of products from rigid concrete mixtures.

The purpose of the invention is to improve the quality of long products by hardening the surface layer and providing strict geometrical dimensions, simplifying stripping and reducing material consumption.

When molding long products from rigid concrete mixtures, the concrete mixture is placed into a mold, followed by a compressive load and directional vibrations with an industrial frequency and amplitude of 0.9-1.5 mm, the molding is performed by pre-rotating shapes at an angle of 1, 5-4.5 ° with respect to the direction of application of the sealing load, affected by the vertical sealing load and directional vibrations that are applied along the sealing load.

The method is carried out as follows.

The shape of the vibropress is set at the vibrating plate with rotation so that the angle between the axis of the mold and the direction of application of the sealing load is 1.5-4.5 °. A rigid concrete mix is placed into the mold (W 100-120 s). The sealing load is created by the punch. Simultaneously with the influence of a compressive load, vibrational oscillations are applied to the mold. Vibration oscillations are carried out with an industrial frequency of 50 Hz and an amplitude of 0.9-1.5 mm, which are applied along a sealing load.

With the vertical walls of the form, gravity forces and pressure forces that occur in the concrete mix during the removal of internal friction forces act on the side surfaces of the product.

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During the molding process of the proposed method, as a result of the transmission of vibration and sealing loads to the side surfaces of the mold, the compacted concrete mix is affected by additionally differently directed vibrations obtained by decomposing the vertically directed vector on the inclined surfaces of the mold.

The combination of sealing load and additional component forces directed perpendicular to the surface of the mold creates additional sealing of the side surfaces.

FIG. 1 shows a diagram of a known molding method; in fig. 2 - scheme S of the proposed method (1 -10 - places to check the surface of the product for strength). Example 1. Formed samples of concrete products with a height of 300 mm from a concrete mixture with a stiffness of 120 with the following composition (1 m mixture), kg:

Portland cement (M "500) 580 Sand (mcr 2.5) 1640

Water180

The shape of the vibroprocess is set on the vibroplate so that the angle between the axis 25 of the mold and the direction of application of the sealing load is 1.5 °. Tough concrete mix is placed in the form. The vertical compaction load is created by the punch. Along with the impact of the compressive load, vibration vibrations are applied to the forum. Vibration oscillations are carried out with an industrial frequency (50 Hz) and an amplitude of 0.9 mm, which are applied along a sealing load.

Hardening of molded products is carried out for 24 hours in a heat chamber at 50-55 ° and 100% humidity.

The tests are carried out with the endentorial method, measuring the compressive strength at points located along the perimeter of the product.

The strength of the product (actual) is measured by cutting cubes.

The amplitude of oscillations is taken within 0.9-1.5 mm, since, with an oscillation amplitude less than 0.9 mm, a strength of 320-330 kgf / cm is not attained in the product, allowed by GOST; With an amplitude of more than 1.5 mm, molding defects (cracks, fractures, etc.) are observed in the product.

The parameters and results of the molding are given in table. 1 and 2.

The use of the proposed method for molding articles from hard concrete mixtures, mainly long ones, provides hardening of the surface layer of products, improving the physicomechanical properties of the surface layer, durability, bearing capacity and quality indicators of products (for example, water absorption, etc.); exclusion of stress concentration zones and destructive changes in products; improving the surface quality of the product, the geometry of the product, reducing the tolerance in the manufacture of products, NTO also significantly reduces the material consumption; creating conditions that allow manufacturing long products, which allows, with the same pressing parameters, to increase the number of simultaneously molded products, i.e., to increase productivity; simplification of the molding process, reduction of time Example 2. Formed samples of concrete 35 molding, increasing productivity.

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products with a height of 300 mm of concrete mix with a stiffness of 120 with the following composition (1 m mixture), kg:

Portland cement (M "500) 580 Sand (mcr 2.5) 1640

Water180

The shape of the vibropress is set on the vibrating plate so that the angle between the axis of the mold and the direction of application of the sealing load is 4.5 °. Tough concrete mix is placed in the form. A vertical packing load is created by the punch. Simultaneously with the influence of a compressive load, vibrational oscillations are applied to the mold. Vibration oscillations are carried out with an industrial frequency (50 Hz)

Claims (1)

Invention Formula The method of forming articles from rigid concrete mixtures, which includes laying the concrete mixture into a mold, compaction with a vertical pressing load and vibration with industrial frequency and vibration amplitude of 0.9-1.5 mm, characterized in that, in order to improve the quality of long products by strengthening prior to compaction, the mold is set at an angle of 1, 5 ° to the vertical, and vibro-galleries with an amplitude of 1.5 mm, which are applied 50 baths are directed along the sealing one. The hardening of the molded products is carried out for 24 hours in a heat chamber at 50-55 ° and 100% humidity. The tests are carried out with the endentorial method, measuring the compressive strength at points located along the perimeter of the product. The strength of the product (actual) is measured by cutting cubes. The amplitude of oscillations is taken within 0.9-1.5 mm, since, with an oscillation amplitude less than 0.9 mm, a strength of 320-330 kgf / cm is not attained in the product, allowed by GOST; With an amplitude of more than 1.5 mm, molding defects (cracks, fractures, etc.) are observed in the product. The parameters and results of the molding are given in table. 1 and 2. The use of the proposed method for molding articles from hard concrete mixtures, mainly long ones, provides hardening of the surface layer of products, improving the physicomechanical properties of the surface layer, durability, bearing capacity and quality indicators of products (for example, water absorption, etc.); exclusion of stress concentration zones and destructive changes in products; improving the surface quality of the product, the geometry of the product, reducing the tolerance in the manufacture of products, NTO also significantly reduces the material consumption; creating conditions that allow manufacturing long products, which allows, with the same pressing parameters, to increase the number of simultaneously molded products, i.e., to increase productivity; simplify pro0 five Invention Formula The method of forming articles from rigid concrete mixtures, which includes laying the concrete mixture into a mold, compaction with a vertical pressing load and vibration with industrial frequency and vibration amplitude of 0.9-1.5 mm, characterized in that, in order to improve the quality of long products by strengthening surface layer and ensure strict geometrical dimensions, simplify stripping and reduce material consumption, before compacting the mold is set at an angle of 1, 5 ° to the vertical, and vibrocol along the sealing load. loads. О 1Л О ОО О О I- with Г П -cf ЧО СО l vT - j with OO o o o in o 4J-1L f co 1 from g -3- - from f co o | - o T VD 1 1 vO 00 with s-ch1- - g with about 00 about 00 about (Y, L VO about 1L OO with -a f f -vf with vD th - about 00 LO CHO CHO 00 go a - - - with o o o o OS rsl o 00 LO chO 1L L SU1 st -vT G - go w y 1 cm go about I-co-cf with ST go - f -) go about about with t 00 about his go go go CNJ (N go f - f go 1L to go -d G about SU t LO W cho go go - go about about with ON T about ON f G with O th -th o LO cm 1L - o ON ON o o o o go th - -3 rd about LO o o o o o - go -) 1L oh oh oh oh oh oh oh  t -vf t t oh oh oh oh oh oh oh oh oh oh oh sh cm LO CJN with G v 1L d G f g - with oh oh oh oh oh ON t vO vO to-3- with: t r r t th m about to CNl ON ON ON 00 r GO 3- O- - OO CO GO o 1L o o vD o ON G DO 1-4D v CO r -a- -a- go Lo o CM o in o 00 4D r vO CO CO -d- - CO LO CM CO o CHO OO LO 4D O LO 4D CO f) t CO о о - CO о 00 1- r- r r CO t t f r GO o CM CHO o 00 o ON lA v) P -) CM CO - -d-) GO u CM o c: - o ON lA chO LO LPi LO GO - -cr -d- r ro tA CO rsi - about r 7 f LO LA -: f CO CO -3-3-3 r) CO ON lA about CM CO LA ON o - - o) - CO - -3- t -d- CO o la o o lA o - - go r f lA oh oh oh oh oh oh oh J- f y - " S Well se vo sh § st; l and. E- S U about 1A s S x (in th and about X this is about Ei ce 1u 0) S se at ABOUT) S S but oh oh oh oh oh oh oh go go go go