SU796755A1 - Method and device for determining raw gas-lime concrete - Google Patents

Description

(54) METHOD FOR DETERMINING THE STRENGTH OF GAS-SILICATE CONCRETE-RAW AND DEVICE FOR ITS IMPLEMENTATION

strength, additionally measure the rate of change of the dielectric constant of the unloaded and loaded samples, and loading the sample of raw concrete is carried out with a constant speed of movement of the dielectric permittivity sensor, and the dielectric constant of the unloaded sample is measured at the time of reaching the measured permeability of the sample of a constant value and measurement of the dielectric constant of the loaded sample was carried out at the moment when the dielectric constant rate of this sample reaches zero.

An apparatus for carrying out the method, including a dielectric constant meter, an applied load meter, a loading device drive, algebraic summing and multiplying units and a registering device, is equipped with a delay unit, a differentiating unit, two AND gates and three memory units, and the loading device outputs connected to the inputs of dielectric meters and the applied load, and the input is connected to the first input of the first memory block and to the first the output of the first logic element I, the output of the dielectric constant meter is connected through a delay unit with the first input of the second memory block, with the input of the differentiating unit and the first input of the third memory unit, the first output of the differentiating unit is connected through the second logical element I with the second input of the second unit memory, the output of which is connected to the first input of the algebraic summation unit, the second output of the differentiating unit is connected to the input of the first logical element And, the second output of which connected to the second input of the third memory block, the first output of which is connected to the second input of the algebraic summation unit, and the second output to the first input of the division unit, the output of the applied load meter is connected to the second input of the first memory block, the output of which is connected to the first input of the block the multiplication, the output of the algebraic sum block is connected to the second input of the division block, the output of which is connected to the second input of the multiplication block, and the output of the multiplication block is connected to the recording instrument.

FIG. 1 shows a block diagram of the device; in fig. 2 - kinetics changed by dielectric constant.

An apparatus for carrying out the method consists of a drive 1 of a loading device, a dielectric constant meter, consisting of a sensor 2 and a meter 3; a meter of the magnitude of the applied load consisting of the sensor 4 and the measuring circuit 5; block 6 delay; differentiator block 7, AND 8 Q and 9 logic elements} of memory blocks 10-12; block 13 algebraic summation; dividing unit 14 / multiplication unit 15; showing device 16.

The device works as follows.

A sensor 2 for the dielectric constant meter and a sensor 4 for the magnitude of the applied load are mounted on the surface of the gas silicate raw concrete. The drive 1 of the loading device is activated, which begins to move the sensors 2 and 4 at a constant speed, pressing them into the surface of the gas concrete or raw material, and the signal from the output of circuit 3 of the dielectric constant through the delay unit 6, which smoothes the possible short-term changes

The Q signal from the noise enters the differentiating unit 7. At a steady-state constant rate of change of the dielectric constant (time t in Fig. 2), block 7 through

logic element 8 gives a signal in

a memory unit 10 for memorizing the value of the dielectric constant of the unloaded sample.

At the time tj (Fig. 2), when the rate of change of the dielectric constant becomes zero, the differentiating unit 7 through the logic element 9 gives a signal to the memory blocks 11 and 12 to remember, respectively, the value of the dielectric constant of the loaded area 6) azts and the value of the applied load and at the same time the signal to turn off the drive 1 loading device. In block 13: algebraic

the summation signals are received from memory blocks 10 and 11 and the difference between the dielectric constant of the loaded and unloaded sample is calculated. In block 14 division

the ratio of the signals from blocks 11 and 13 is calculated. A multiplication block 15 multiplies the signal of block 14 and the signal of block 12 proportional to the value of the applied load

About the measuring circuit 5. At the output {Zloka 15 multiplying the signal is proportional to the value characterizing the strength properties of the gas-silicate raw concrete. This signal is registered with the indicating device 16.

The method is as follows.

On the surface of the gas silicate concrete raw set sensor 2 gauge dielectric constant and sensor 4 gauge the magnitude of the applied load. The drive 1 of the loading device is switched on, which moves the sensors 2 and 4 at a constant speed, the dielectric constant of the raw concrete, its rate of change and the magnitude of the applied load are measured. At the moment when the rate of change of the dielectric constant becomes constant, which corresponds to the value of t in FIG. 2, the dielectric constant value CQ of the unloaded product is determined. The dielectric constant of the loaded product is determined at its rate of change equal to zero, which corresponds to the moment -fc in FIG. 2. Then, using blocks 13 of algebraic summation, division 14 and multiplication 15, the strength value of the gas-silicate raw concrete is calculated.

Moving the sensor to measure the dielectric constant needs to be performed at a constant speed, as this will allow you to accurately determine the value of the dielectric constant of the unloaded product. The moment when the rate of change of the dielectric constant becomes constant corresponds to the moment when all the electrodes are in close contact with the concrete, and fully characterizes the dielectric properties of the unloaded sample.

Claims (2)

1. A method for determining the strength of a gas silicate raw concrete, including loading a sample of a concrete pipe, measuring the dielectric constant of the unloaded and loaded samples, as well as the magnitude of the applied load and calculating on their Basis the limit, compressive strength, characterized in that, in order to improve accuracy, the rate of change of the dielectric constant of the unloaded and loaded samples is measured, and the loading of the sample of the raw concrete is carried out at a constant rate of movement and The dielectric constant and the dielectric constant of the unloaded sample are measured when the measured dielectric constant of the sample reaches a constant value, and the dielectric constant of the loaded sample is measured when the dielectric constant of the sample reaches zero. 2. An apparatus for carrying out the method of claim 1, comprising a dielectric constant meter, an applied load meter, a loading device drive, algebraic summing, dividing and multiplying units and a registering device, different in that the device is equipped with a delay unit, a differentiating unit logical elements And and three blocks 1I memory, and the drive output of the loading device is connected to the inputs of the dielectric meters and the applied load, and the input dinene with the first input of the first memory block and with the first output of the first 5 of the logic element And, the output of the dielectric constant meter is connected through the charging unit to the first input of the second memory unit with the input of the differentiating unit on 0 with the first input of the third memory block, the first output of the differential module of the block is connected via the second logic element AND with the second input of the second memory block, the output of which 5 is connected to the first input of the algebraic summation unit, the second output of the differentiating unit is connected to the input of the first logical element And, the second output of which 0 is connected to the second input of the third memory block, the first output of which is connected to the second input of the algebraic summing unit, and the second output to the first input of the dividing unit, the output of the meter attached 1 load is connected to the second input of the first pee unit, the output of which is connected to the first input of the multiplication layer, the output of the algebraic sum block is connected to the second 0 by the input of the division unit, the output of which is connected to the second input of the multiplication unit, and the output of the multiplication unit is connected to the recording device. Information sources, 5 taken into account in the examination 1. Authors certificate of the USSR P 246901, cl. G 01 N 3/00, 1968. 2. Author's testimony of the USSR. 532784, cl. G 01 N 3/08, 1977.