SU1249459A1 - Method of automatic correcting of proportions of concrete mix - Google Patents

Abstract

The invention improves the accuracy of the correction. The granulometric composition of the coarse aggregate mixture is stabilized. Adjust the flow of water and cement. Dispense components, mix in a concrete mixer. The actual cone settlement (TFR) is determined. Adjust the flow of water and cement, taking into account the received FCF. Adjust the doses of aggregates - rubble and sand & 1 silt. (О С KD 4; about 4 СЛ СО

Description

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The invention relates to the production of building materials and products, mainly concretes and reinforced concrete, and can be used in the automation of concrete mixing plants and workshops, in particular in the cyclical preparation of heavy concretes, for example, in concrete plants for the construction of hydroelectric power plants when producing hydraulic concretes.

The purpose of the invention is to improve the accuracy of the correction.

The essence of the method for automatically correcting the composition of a concrete mix is as follows.

At the beginning, according to the molds (1) - (3), the granulometric composition of the mixture of coarse aggregates is stabilized and the consumption of water and cement is adjusted:

Г D, aLJ / (1 + W.) Dj, 1ii. :four

J :: 1

(one)

where D is the dose of the mixed jth fraction

I (), dose of pure i-th fraction

 ()but . - - pure content: 1st fraction in metered fraction j (1Ui4); (Uji4); W. - moisture dosage amay t-th fraction

D; b ,,., (2)

where Dg is the calculated dose of water;

OK-set cone sediment

SSQ sand surface area

TP-fineness of cement;

B, b, empirical coefficients;

D ° (b5l5j: k..) D

8 b (3)

where D ° - the estimated dose of cement;

R ° 5 is the specified concrete strength, bg-bg are empirical coefficients ,.

After this, the dosing of components is carried out, their further mixing in a concrete mixer and, according to the proposed automatic correction method, the actual precipitation of the OK cone is measured. After that, a new calculated value of the dose in terms of D is determined by replacing in the formula (2) the OKj value with the received value - OK, i.e.

Oe b ,,, TP,

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Taking into account the water content of the aggregators, we obtain the required value of the dose of water

 g y -. ,,

(four)

g- -c

t de L D; W - water content of 1-1 tons

stitches, after which the dose of cement is determined, D, jcp i

D. DB. K. (5)

where K is the cement-water ratio specified for a given concrete brand.

Then, the adjusted doses of aggregates — crushed stone and sand are determined:

D ,,, T, (0,453 Yu, 182aP ,, - L24l -,.,) Y

where Dyj is the adjusted dose

rubble

LP - change in the voidness of sand relative to the magnitude of P. 0.37, dVg - change in the volume of the dosed water relative to the 4V formulation, (Dg -Dp / Jl,

g, tse - bulk density of wool aV u, - change in the volume of cement being metered: a relative to the formulation uV (D CP-D;) / - Y

where Y is the bulk density of cement,

yv - the volume density of rubble. Adjusted dose

sand is defined as

Dr ,, q, (0.547-0, | 82dG h-0.24d72-a-yU - -V-4, .p) -V ,, (7)

d de - corrected value

doses of sand - the bulk density of sand;

Dr

and V

Chef

6

 RF

f ,.

- semi

Actual volumes of water and cement, respectively, as a result of correction

s- - correction factor (at., t, -350 kg / m s IjO j at

D .., kg / mz ci 0.94).

Thus, the determination in the process of automatic correction of the composition of the concrete mixture values and

T) r1f is the so-called second correction circuit, which makes it possible to more accurately obtain as a result of preparing the mixture a given recipe (brand) and thereby improve both the quality of the mixture itself and its products (concrete, reinforced concrete, ready-mixed concrete, and .d.)

The drawing shows one of the variants of a block diagram of a device for implementing a method for automatically correcting the composition of a concrete mix.

In regulator 1, the granulometric composition of aggregates is stabilized according to the system of equations of. formula (1). In computing unit 2, D ° is determined according to formula (2). In computing unit 3, the value of Hc is determined according to formula (3). In computational unit 4, empirical coefficients b - b ,, are determined. B

I o

computational block 5 filters and predicts the values of a .., W, Syg, TP OK, p, P, (P ,, - actual sand voidness).

In the driver unit 6, the express control of the values of D, Csr,, Djjq, is performed. In the computing unit 7, the values are determined respectively by formulas (4) - (7), the control unit 8 controls the batching of the components.

The device works as follows.

Before the first cycle of concrete preparation in block 6, the values of a j, Wj,, TP are determined. These values (electrical signals in analog or digital form, depending on the technical implementation of the device) are fed to the input of block 5, where they are filtered and predicted for the next concrete mix preparation cycle,

From the first information output of block 5, electrical signals are sent to the controller — a.j and Wj; in block

2- S., TP, W, in block 3 - TP, From the second information output of block 5, block 4 receives the values a-, i

hi1 J

Wj; S i TP, and also after the first cycle - preparation of the concrete mix OK, P, C of the first output of block 4, the second input of block 3 receives the values R °, bj-bjj, and then in the block

3determines the preset value DiT,

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The second input of block 2 from the first output of block 4 receives the values,, and then in block 2 the value D. is determined. To the second entrance

g

5 of the regulator 1, the values of, W are received from the first output of block 4, after which, in block 4, the values of D are calculated ..

Thus, in controller 1 and 0, blocks 2 and 3, respectively, the values of D, D ° and D, which are the calculated values of the component doses for the first concrete mix preparation cycle, are determined. After this, the block 8 controls the dosing of the components and after they are finished dosing, mixing, determining the actual slump of the OK cone, the device starts (if the deviation of OK, from OK) takes place, correcting the composition of the concrete mix. Preliminary, in block 6, a ,,, W., OK, p, S ,,, is determined; TP; P",

Further, the values of OK and P through

5, block 5 and block 4 are fed to one of the inputs of block 7, the other inputs of which come from the blocks of controller 1 and blocks 1 to 3 of the calculated values, D, D, T) °. After that in

0 block 7, the calculation of the doses of 0 „f, D Dg, p and for the next (second cycle) preparation of the concrete mix.

Block 8 is provided with a block by which information is received only from the output of block 7, that is, e. values of D, D ,, D, and D.. If OK is OK, (or their difference is in permissible

 cic norms), the blocking is absent and the second concrete mix preparation cycle is carried out according to the previously determined values of Dj, D and.

The method of automatically correcting the composition of a concrete mix provides the ability to comply with accuracy. The specified recipe of the mixture and reduction of the variation coefficient of the solidity of finished products by an average of 8-12%, which, in turn, allows for 10-15% to reduce the standard consumption of cement for the preparation of 1 m of concrete mix.

five

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Claims (1)

Invention Formula The method of automatic correction of the composition of the concrete mix, including determination of water dose of cement depending on the content of sand, rubble, water and cement in the mixture, water content of aggregates, given cone sediment, specific surface of sand, fineness of cement, given concrete strength, so as to increase the accuracy corrections measure changes in sand voidness 1249459 & and the bulk density of sand and rubble, after each component dosing cycle, the actual J is the amount of precipitation of the cone according to which the adjusted doses of water and cement are calculated, after which the doses of rubble and sand are calculated depending on the adjusted doses of water and. a change in the voidness of sand and bulk densities of sand and rubble.