SU1735000A1 - Vibration platform for compacting concrete mixes - Google Patents

Description

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The invention relates to equipment for the production of precast concrete and reinforced concrete products, namely, vibrating platforms for compacting concrete mixtures in a mold, and can be used in factories and enterprises of the construction industry.

A vibrating plate is known, comprising a working body mounted on the base and connected to each other by means of coaxial elastic elements and a balancing frame on which the crank exciter is mounted, and the working body has an elastic gasket.

The disadvantage of this design is the complexity due to the presence of a 3-mass oscillatory system, a crank oscillator, as well as the inability to control the mode of operation.

Also known vibroplatform for compaction of concrete mixes, containing a movable frame mounted on elastic pneumo-pores with a pathogen of vertically directed oscillations in contact with an elastic buffer element located under it and mounted on the base.

The disadvantage of this vibroplatform is the limited range of use of the pad due to the low vibration frequency, the presence of a foundation. In addition, it consumes a significant amount of electricity.

The purpose of the invention is to intensify the processes of compaction and reduce energy intensity.

The goal is achieved by the fact that at the vibroplatform for compacting concrete mixtures containing a movable frame installed on elastic pneumo-supports, with a vertical-directional oscillation pathogen, in contact with an elastic buffer element located underneath and mounted on the base, the composite are unrelated to each other blocked in pairs and located symmetrically to the causative agent of vertically directed sections, placed between elastic pneumatic supports, and the rigidity of one of the sections ugogo buffer element in each pair exceeds 1.05-1.1 times the stiffness of the other section, and stiffness of the movable frame flexural - 1000 - 1500 times the stiffness of any of the sections of the elastic buffer element

FIG. 1 shows a vibroplatform, side view; Fig 2 - placement of elastic pneumo support, sections of the buffer element and

pathogens of vertically directed oscillations.

The vibrating platform for compacting concrete mixes contains a movable frame 2 mounted on elastic pneumo-supports 1 with an exciter 3 vertically oscillations. The frame 2 is in contact with the buffer element 5 located under it and mounted on the base 4.

A gasket 6 is attached to the frame 2. The buffer element is made up of a composite of vertically directed sections 7 not connected to each other, interlocked in pairs and arranged symmetrically

driver 3, is a tube with a glass with an elastic gasket. Sections 7 are placed between the pneumatic supports 1. The rigidity of one section 7 in each pair exceeds 1.05 - 1.1 times the rigidity of the other

section, and the rigidity of the movable frame 2 on bending in 1000 - 1500 times the rigidity of any of the sections of the elastic buffer element 5.

The stiffness of the gasket 6 is selected from

working conditions of the two-mass oscillatory system of pneumatic support - movable frame - elastic gasket - form with a mixture in the resonant mode, i.e. by the formula

thirty

  but,

where t is the vibrating mass;

O) is the frequency of the forcing action.

The vibrating platform works as follows.

On the working body - mobile frame 2, the mold is freely set and filled with concrete.

As the mold is filled and its weight increases, the pneumatic supports 1 are compressed, the gap between the frame and the buffer element is selected, and then the weight of the frame and the mold with the mixture is transferred through the buffer element 5 to the base 4. Compressed air pneumatic supports 1 are supplied in pairs, connected in pairs, whose pressure is chosen such that the ratio

R ,

where 5 eff is the effective area of pneumo support, m;

Q - weight of the form with a concrete mix. at the same time, a gap is formed between the buffer element and the lower plane of frame 2, the magnitude of which does not depend on the mass of the molded product, but varies depending on the magnitude of the disturbing force of the pathogen in the compaction process within 0.1-0.2 mm, after which the causative agent is included 3, while the force generated last, changing according to the harmonic law, forces the frame to form with vertical oscillations and, when the frame moves down, its lower plane collides with the buffer element. The acceleration received by the concrete mix upward is determined by the chosen optimum value of the rigidity of the sections of the buffer element and the frame material (the rigidity of the first is 1000–1500 times greater than the bending stiffness of the latter).

In addition to the vertical oscillations of the shape, in view of the accepted ratio of stiffnesses of the opposite sections of the buffer element 1.05-1.1, the torsional vibrations of the shape with the concrete mixture also occur, which improves the compaction process. As the pressure of compressed air in pneumatic supports increases by 10–20%, the mode of oscillation of the working member – frame changes, in which case the impact occurs after two turns of the exciter shaft, the acceleration of the form with the mixture increases, and the spectrum of oscillations is enriched with new harmonics.

After compaction of the mixture simultaneously with the exclusion of pathogens reset

air pressure in the pneumatic supports and remove the form from the vibrating plate,

The use of the proposed vibroplatform allows to increase the efficiency of compaction of rigid concrete mixtures by 10-20%, reduce power consumption, expand the technological capabilities of its use, and in addition, reject the foundation construction.

Claims (1)

Claims for compacting concrete mixes containing a movable frame mounted on elastic pneumatic supports with an exciter of vertically directed oscillations in contact with an elastic buffer element located underneath and mounted on the base, in order to intensify the compacting processes and reduce energy intensity. the buffer element is made of a composite of vertically directed, unrelated in pairs interlocked in pairs and located symmetrically to the pathogen oscillations of sections placed between elastic pneumatic suppressors, with the rigidity of one of the sections of the elastic buffer element in each pair exceeding 1.05-1.1 times the rigidity of the other section, and the rigidity of the movable frame for bending exceeds 1000-1,500 times the rigidity any of the sections of the elastic buffer element. 8 5 3