SU966136A1 - Apparatus for measuring road pavement irregularities - Google Patents

Description

The invention relates to road construction and may find application in the design of pavement. Advantageously, the invention can be used to determine the dynamic coefficient of roads. In addition, it can be used to assess the condition of roads in use.

A device for measuring surface roughness is known, comprising a sensor, a carrier frequency generator, a supply sensor and series-connected amplifier of the measuring signal carrier frequency, a 'detector and a recording unit [1].

The disadvantage of this device is the significant complexity of the way. boots received dynrs.

The closest in technical essence to the proposed one is a device for measuring unevenness of the road surface, containing acceleration and load meters, which are connected through a series-connected corresponding amplifier and filter to the corresponding inputs of the adder, the first recording unit [21.

; The disadvantages of the known device are the complexity of processing the received data and low measurement accuracy. .

These shortcomings are due to the fact that in the process of decoding the waveform corresponding to the recording of the dynamic coefficient on the kilometer section of the road, it’s necessary to measure and process up to 10,000 signal amplitudes, and manual processing is not very accurate.

’The aim of the invention is to improve the accuracy of measurement.

'This goal is achieved by the fact that,' a device for measuring road surface irregularities, containing acceleration and load meters that are connected via a series-connected respective ^{amplifier ζυ amplifier} and filter to the corresponding inputs of the adder, and the recording unit is equipped with an extremator, an analog-to-digital converter, a decryptor, a counter and a switch,

2? the output of the adder is connected directly to one of the inputs of the analog-to-digital converter, and to the other input through an extremator, the output of the analog-to-digital converter is connected via a decryptor and a counter connected in series to the corresponding inputs of the switch, the output of which is connected to the recording unit.

The drawing shows a device.

The device contains a teneost bridge 1, a piezoelectric accelerometer 2, amplifiers 3, filters 4, a sumator 5, an extremator 6, an analog-to-digital converter 7, a decoder 8, a counter 9, a switch 10, a recording-_ block 11, made in the form of an indication block 12 and belt punch 13.

The device operates as follows.

When the car is moving, the signals from the strain gauge bridge 1 and the piezoelectric accelerometer 2 through matching amplifiers 3 and filters 4 enter the adder 5, which summarizes the signals of the strain gauge bridge 1 and the piezoelectric accelerometer 2. The total signal is fed to the input of the analog-to-digital converter 7, where the amplitude is measured the input signal at a point in time corresponding to its extreme value, which is fixed by the extremator 6, and generates a start pulse of an analog-digital converter 7, then depending m code decoder 8 sends a signal to one channel of a multichannel pulse counter 9, in which the entire range of variation of the sum signal · characterizing the dynamic factor is divided into twelve levels (channels). In the multi-channel pulse counter 9, the number of pulses in each channel is counted, the channel commander 10 sequentially polls each channel and displays the measurement results on the recording unit 11, where they fall into the display unit 12 and the tape drill 13.

This design of the device allows you to measure the analog signal in an analog-to-digital converter at the time of its extremum, to distribute and sum the number of extreme points depending on their input level. Due to such processing, the amount of information that needs to be recorded is reduced. As a result of measurements of the dynamic coefficient on a kilometer stretch of road, instead of an oscillogram that needs to be decoded, measured signals on it and processed data, we get twelve numbers characterizing the measurement range of the CD and its distribution density.

The economic effect of the introduction of this device in accordance with the Instruction CH 509-78 is calculated by the formula

E = ⁽ _{3 <} b _{£ +} e _{s-s 2} ) _A , where 3 ₁ and 3 ₂ are the reduced costs for the manufacture of a prototype device and a new one, respectively:

В ^ and В-2 - productivity on test operations according to options;

£ = _1, since the service life of the new device corresponds to the replaceable one;

E _with - savings in the field of operation of the device (only changes in wages are taken into account, all other cost items for the options are not changed);

A - the volume of implementation, pcs. 8 according to the Ministry of Transport and is

E = (1000.1 ^ 5 · - 1 + 19.8-2.3)> 8 = = 192.0 thousand rubles. in year.

This device allows to increase the accuracy of measurement.

Claims (2)

connected decoder and counter to the corresponding inputs of the switch, the output of which is connected to the registering unit. The drawing shows the device. The device contains a strain gauge 1, a piezoelectric accelerometer 2, amplifiers 3, filters 4, an adder 5, an extremator 6, an analog-to-digital converter 7, a decoder 8, a counter 9, a switch 10, a registering unit 11, made in the form of an indication unit 12 and a ribbon one perorator 13. The device operates as follows. When the car moves, the signals of the tensometer 1 and the piezoelectric accelerometer 2 through matching 3 and filters 4 enter the sum of the matrix 5, which summarizes the signals of the tensometer 1 and the piezoelectric accelerometer 2. The total signal goes to the input of the analog-digital converter 7, where the amplitude is measured of the input signal at the moment of time, corresponding to its extreme value, which is fixed by extremator 6, and generates an impulse to start the analog-to-digital converter 7, then depending on the code And the decoder 8 sends the signal to one of the channels of the multichannel pulse counter in which the whole range of variation of the total signal, characterizing the dynamic factor, divides from to twelve levels (channels). A multichannel pulse counter 9 counts the number of pulses in each channel, the switch of channel 1 sequentially polls each channel and the measurement results are output to the recording unit 11, where they fall into the display unit 12 and on the tape perforator 13. Such an instrument design allows an analog signal to be measured in analog logo-digital converter at the time of its extremum / carry out the distribution and summation of the number of extreme points depending on their input level. Through such processing, the amount of information that needs to be recorded is reduced. As a result of measurements of the dynamic coefficient on the kilometer stretch of the road, instead of the oscillogram, which needs to be decoded, the signals on it are measured, and the data are processed, twelve numbers are obtained that characterize the measuring range Cd and its density. The economic effect of the introduction of this device in accordance with Instruction CH 509-78 is calculated by the formula () A and Zo, the reduced costs for the manufacture of a prototype device and a new one, respectively: B and B are the performance of the control and measurement work on the options; as the term of the servant of the New device corresponds to the replaced; savings in the field of operation of the device (only the change in wages is taken into account, all other cost items for the options do not change); the volume of implementation, piece 8 according to the Ministry of Transport and Construction, is e (1000.1 -1 + 19, 8-2.3) -8 192.0 thousand rubles. in year. This device improves measurement accuracy. Apparatus for measuring road surface irregularities, comprising acceleration and load meters, which are connected via series-connected corresponding amplifier and filter to the corresponding inputs of the adder, and a recording unit, characterized in that, for the purpose of improved measurement accuracy, it is equipped with an extrementer analog -digital converter, decoder, counter and switch, and the output of the adder is connected to one of the inputs of the angular-digital converter directly enno, and the other input -through ekstremator, output of the analog-digital converter is connected via series connected counter and decoder to respective inputs of a switch, whose output is connected to the recording unit. Sources of information, rintye taken into account in the examination 1. The author's certificate of the USSR 482617, cl. G, 01 B 7/34, 1972. 2. Smirnov Yu.I. et al. Methods of measuring dynamic loads under a car's road and determining road ovality. Proceedings of the Union 110. M., 1979, p. 57-69. (prototype). f