JP2000046807A - Apparatus and method for inspecting ejected muddy state of roadbed - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the subject apparatus and method capable of continuously inspecting roadbed ballast in a non-contact state while running and avoiding the effect of a crosstie. SOLUTION: A speaker 12 emitting a sound wave within an audible frequency range to roadbed ballast, a microphone 14 converting the reflected sound generated when the sound wave is reflected by the roadbed ballast to a sound pressure level and a sound pressure level analyser 16 converting the sound pressure signal to a sound pressure level are provided. The sound pressure level of a reflected sound of a frequency region of 160-315 Hz is analyzed in frequency by a sound pressure level analyzer and, from the difference with a standard sound pressure level, a roadbed ejected muddy state is inspected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and a method for measuring the state of a bed of a railway track.

[0002]

2. Description of the Related Art FIG. 6 is a schematic sectional view of a railway track. As shown in this figure, the railroad track is composed of two rails 1 for directly supporting a vehicle and a sleeper 2 for supporting the rails, and crushed stones 3 (ballast) are spread under the rails and the sleepers. I have. This ballast portion is called "ballast ballast". The ballast ballast in the normal state is crushed stone 3.
(Ballasts) contact each other to form a gap inside, support the rails 1 via the sleepers 2 to disperse the load of the vehicle on the roadbed, buffer the impact and noise when the vehicle passes, and improve the ride comfort of the vehicle. Contribute to the improvement of The rail is fixed to the sleeper by a fastening device including a fastening fitting 5a and a fastening bolt 5b.

[0003] However, the ballast is subjected to the load and impact of the vehicle running repeatedly, and is crushed and gradually refined by the impact of compaction work by a maintenance machine. The fine ballast ballast becomes the mud 4 due to the rainwater, is gradually sucked up by the vibration when passing through the vehicle, and finally the mud 4 is clogged up to the surface of the road bed. As a result, there arises a problem that the load dispersing ability of the crushed stone (ballast) is reduced, or the elasticity is reduced, so that the shock and noise damping capacity is reduced and the riding comfort of the vehicle is deteriorated.

[0004] For this reason, the ballast in the target area is dug up by manpower or mechanical equipment, and the degree of fineness of the ballast, that is, the degree of deterioration of the ballast is confirmed to estimate the replacement time.

[0005]

However, the work of digging / backfilling the ballast ballast requires a lot of labor and a great deal of time and money. Therefore, means for diagnosing the ballast without digging the ballast is required. Various proposals have been made (for example, JP-A-10-26576, JP-A-10-
26577).

Japanese Unexamined Patent Publication No. Hei 10-26576 discloses an apparatus for diagnosing and evaluating the degree of deterioration of a ballast ballast, in which a vibrator is installed on the upper surface of a ballast ballast or on a sleeper to vibrate the ballast ballast or a sleeper and at the same time, simultaneously generate a response signal. By measuring,
The excitation force at the excitation point is simultaneously taken into the measuring device to diagnose and evaluate the degree of deterioration.

[0007] Further, in Japanese Patent Application Laid-Open No. Hei 10-26577, a "ballast ballast deterioration diagnosing apparatus" vibrates the surface of a roadbed by vibrating means, and vibrates at a location distant from the vibrating place by vibrating means. Receives the elastic waves that are generated and propagated inside the trackbed, and calculates the velocity of the elastic waves propagating through the trackbed from the time difference between the signal from the vibration generator and the signal from the vibration receiver when the vibration is generated. The non-destructive diagnosis of the degree of deterioration of the roadbed is made based on the velocity of the elastic wave.

[0008] However, in the conventional means, it is necessary to bring the exciter or the exciter into contact with the roadbed or the sleeper, and therefore, it is necessary to stop the measuring cart at the measuring point. For this reason, it is necessary to frequently move and stop the apparatus, and there is a problem that the average moving speed of the apparatus is low.

The present invention has been made to solve such a problem. That is, the main object of the present invention is to
It is an object of the present invention to provide a ballast inspection apparatus and a ballast inspection method capable of inspecting a ballast ballast in a non-contact manner. Another object of the present invention is to provide an apparatus and a method capable of performing non-contact and continuous inspection while running. Furthermore,
Another object of the present invention is to provide an apparatus and a method capable of non-contact inspection of a ballast ballast while avoiding the effects of sleepers.

[0010]

Means for Solving the Problems The inventor of the present invention uses FIG.
Attention was paid to the position of the mud exemplarily described in (1), and various basic tests were performed on the possibility of measuring this position from the sound pressure level of the reflected sound. According to this basic test, the sound absorption coefficient of the mud is low and the sound pressure level of the reflected sound is high. Conversely, the sound absorption coefficient of the ballast ballast is high (close to the sound absorbing material) and the sound pressure level of the reflected sound is low. In the case where there is mud under the ballast, the sound pressure level of the reflected sound decreases almost in inverse proportion to the thickness of the ballast. The present invention is based on such a new finding.

That is, according to the present invention, a speaker (12) radiating a sound wave whose frequency is in the range of human audible frequencies to a ballast ballast, and a sound reflected by the ballast ballast as a sound pressure signal Microphone (1
4) and a sound pressure level analyzer (16) for converting the sound pressure signal into a sound pressure level, and inspecting the state of the bed material mud from the sound pressure level of the reflected sound. A mud condition inspection device is provided.

According to the present invention, a sound wave whose frequency is in the range of human audible frequencies is radiated to the ballast, and the sound reflected by the ballast is converted into a sound pressure signal. Is converted into a sound pressure level, and the state of the bedded mud is inspected from the sound pressure level.

According to the apparatus and method of the present invention, a fixed level sound wave is radiated from the speaker (12) to the ballast, the reflected sound is converted into a sound pressure signal by the microphone (14), and the sound pressure level is analyzed. By converting the sound pressure level into the sound pressure level by the vessel (16), the sound pressure level of the reflected sound from the ballast can be analyzed. Therefore, based on the results of the above-described basic test, the position of the mud under the ballast is estimated in a non-contact manner from the degree of the decrease in the sound pressure level of the reflected sound, and the state of the ballast is diagnosed and inspected. be able to.

According to a preferred embodiment of the present invention, the sound pressure level of the reflected sound is analyzed by the sound pressure level analyzer based on the frequency characteristic of the C characteristic, and the state of the bedbed mud is determined from the difference from the reference sound pressure level. inspect. As a sound pressure level analyzer, the sound pressure level was measured using the A and C characteristics of the sound level meter, and by analyzing the frequency characteristics of the C characteristics, the sound pressure level was reduced almost in inverse proportion to the thickness of the ballast. The basic test showed that it could be done. Therefore, the sound pressure level of the reflected sound is C
By analyzing the characteristic frequency characteristics, it is possible to more accurately inspect the state of the road bed mud.

Further, according to another preferred embodiment, the sound pressure level analyzer analyzes the sound pressure level of the reflected sound in the frequency range of 160 to 315 Hz, and analyzes the sound pressure level from the difference from the reference sound pressure level. Inspect the mud condition. As a result of frequency analysis of the sound pressure levels of the A characteristic and the C characteristic of the sound level meter, it was confirmed that the decrease in the sound pressure level was almost inversely proportional to the thickness of the ballast in both frequency ranges of 160 to 315 Hz. Therefore, by limiting the frequency range of the reflected sound to be measured to this range, each device can be optimized and the accuracy can be further improved.

Further, a sound measurement case (18) containing the speaker and the microphone is further provided, and a lower surface of the sound measurement case has an opening (18a) for covering only a ballast between adjacent sleepers. By providing the sound measurement case (18), the influence of external noise can be reduced. In addition, by configuring the opening (18a) to cover only the ballast ballast between the adjacent sleepers, it is possible to inspect only the ballast ballast portion while avoiding the influence of the sleeper.

Further, a sound absorbing material (19) is preferably adhered to the inner surface of the sound measuring case. With this configuration, the internal reflection sound due to the sound measurement case (18) can be reduced, and the measurement accuracy of the reflection sound from the ballast can be increased.

Furthermore, a flexible and sound-insulating skirt member (20) surrounding the opening is provided between the lower surface of the sound measuring case and the ballast. Such a skirt member (20)
, It is possible to reduce the entry of noise (reflected sound from rails or sleepers) from the gap between the lower surface of the sound measurement case and the ballast.

It is preferable that the sound measurement case is a sound field that has no parallel surface with the ballast and does not allow the sound source of the speaker to directly enter the microphone. By using such a sound field, it is possible to avoid the influence of sound pressure fluctuation due to a standing wave that easily occurs between parallel planes, prevent a sound source of a speaker from directly entering the microphone, and reduce the intrusion of external noise. .

It is preferable that the speaker emits a short-time sound wave intermittently between sleepers. With this configuration, it is possible to radiate sound waves only to the ballast ballast between the adjacent sleepers, reduce the reflected sound from the sleeper, avoid the influence thereof, and inspect only the ballast ballast portion.

Further, it is preferable that a sleeper sensor (22) for detecting a position of the sleeper is further provided. For example, by detecting the head of the rail fixing bolt with a laser sensor or the like, the position of the sleeper is detected, and the inspection at that position is stopped,
Alternatively, by correcting the data, the influence of the crossties can be avoided and the inspection accuracy can be improved.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. In addition, the same reference numerals are given to the common parts in the respective drawings, and the duplicate description will be omitted. FIG. 1 shows a first embodiment of a track bed mud inspection apparatus according to the present invention.
It is a lineblock diagram showing an embodiment. As shown in this figure, a trackbed mud condition inspection apparatus 10 of the present invention includes a speaker 12 that radiates sound waves in an audible frequency range (for example, several tens to 20,000 Hz) to a ballast 3, The microphone 14 includes a microphone 14 that converts a sound wave reflected by the ballast 3 into a sound pressure signal, and a sound pressure level analyzer 16 that converts the sound pressure signal into a sound pressure level.

The speaker 12 amplifies the sound having a frequency in the audible frequency range outputted from the DAT 11a by the amplifier 11b and radiates the sound to the ballast 3 at a predetermined sound pressure level. The sound in the audible frequency range of 50 to 5000 Hz can be easily radiated from a normal speaker, for example, a loudspeaker. Further, it is preferable that the amplifier 11b can flatten the frequency characteristic of the sound pressure of the sound wave radiated from the speaker 12.

The microphone 14 is installed at a position where direct sound from the speaker 12 does not enter. The microphone 14 is preferably omnidirectional. In this example, the sound pressure level analyzer 16 includes a sound pressure gauge 16a, a data recorder 16b, an analyzer 16c, and the computer 1
6d, the sound pressure signal of the reflected sound captured by the microphone 14 is converted into a sound pressure level, and this data is recorded in the data recorder 16b. It estimates the position of the mud below and diagnoses and inspects the ballast ballast condition.

In the first embodiment shown in FIG. 1, the roadbed mud condition inspection apparatus 10 of the present invention further includes a sound measurement case 18 in which a speaker 12 and a microphone 14 are built. Also,
The lower surface of the sound measurement case 18 has an opening 18a. Further, a sound absorbing material 19 is adhered to the inner surface of the sound measuring case 18, and a flexible and sound insulating skirt member 20 surrounding the opening 18 a is attached between the lower surface of the sound measuring case 18 and the ballast ballast 3. ing.

By providing the sound measuring case 18, the influence of external noise can be reduced. Further, by adhering the sound absorbing material 19 to the inner surface of the sound measuring case 18, the internal reflection sound by the sound measuring case 18 can be reduced, and the measurement accuracy of the reflection sound from the ballast 3 can be increased.
By providing the flexible and sound-insulating skirt member 20, it is possible to reduce the entry of noise (reflected sound from rails and sleepers) from the gap between the lower surface of the sound measurement case 18 and the ballast 3. As shown in FIG. 1, a reflection plate 18b is appropriately provided inside the sound measurement case 18 to
The sound reflected from the speaker 12 may be reflected toward the ballast 3, and the sound wave from the speaker 12 may be reflected a plurality of times between the ballast 3 and the reflector 18 b before reaching the microphone 14. With this configuration, the change rate of the sound pressure level due to the difference in the sound absorption coefficient of the ballast 3 can be increased, and the inspection accuracy can be increased.

The sound measuring case 18 is preferably a sound field which has no parallel surface with the ballast 3 and does not allow the sound source of the speaker 12 to enter the microphone 14 directly. As a structure of this sound field, for example, it is conceivable to provide a shielding plate 24 between the microphone 14 and the speaker 12. By using such a sound field, it is possible to avoid the effect of sound pressure fluctuation due to a standing wave that easily occurs between parallel surfaces,
By preventing the sound source of the speaker from directly entering the microphone, it is possible to reduce the entry of external noise,
Only the reflected sound from the roadbed can be extracted.

FIG. 2 is a block diagram showing a second embodiment of a roadbed mud condition inspection apparatus according to the present invention. In this figure, (A) is a plan view, (B) is a cross-sectional view taken along line AA, and (C) is a schematic diagram of a sound pressure level of a reflected sound. In this figure, a roadbed mud condition inspection apparatus 10 of the present invention uses a wheel 17 on a rail 1 at a predetermined speed (for example, 30 km).
/ H). Further, in this example, the sound measurement case 18 is configured to have a size to enter between the adjacent sleepers 2, and the opening 18a is configured to cover only the ballast ballast 3 between the adjacent sleepers.
With this configuration, it is possible to inspect only the ballast portion of the ballast while avoiding the influence of the sleeper 2.

As shown in this figure, a sleeper sensor 22 for detecting the position of the sleeper 2 is further provided. The sleeper sensor 22 is, for example, a laser sensor that detects the head of the rail fixing bolt, detects the position of the sleeper 2 and stops the inspection at that position, or corrects the data to detect the position of the sleeper 2. Inspection accuracy is improved by avoiding the influence of the above. Further, it is preferable to include a measurement position sensor 23 for detecting the measurement position. Since the data recorder simultaneously records the measurement position data output from the measurement position sensor 23 with the measurement data, the measurement data can be associated with the measurement position. Measurement position sensor 2
As 3, a rotary encoder provided on the axle can be considered. Further, in order to reduce the influence of the sleeper 2, the speaker 12 emits a sound wave intermittently only between the sleepers 2, or measures the reflected sound only when it is located between the sleepers 2. It is good to configure. That is, as described later, when the reflected sound from the ballast 3 is measured while the sleeper is present, the sound pressure level of the reflected sound from the position of the sleeper increases as schematically shown in FIG. Therefore, the reflected sound of the ballast 3 cannot be accurately measured as it is. Therefore, as described above, by limiting the measurement of radiation or reflected sound of sound waves only to the sleepers 2, it is possible to avoid the influence of the sleepers 2 and inspect only the ballast ballast portion.

Further, according to the method of the present invention using the above-described apparatus, a sound wave having a frequency in the range of 250 to 5000 Hz is radiated to the ballast, and the sound reflected by the ballast is converted into a sound pressure signal. Then, the sound pressure signal is converted into a sound pressure level, and the state of the bed mud is inspected from the sound pressure level.

[0031]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The results of a basic test conducted to confirm the principle of the present invention will be described below. In this basic test, FIG.
A test track (not shown) simulating the railroad track shown in (1) was installed. This test bed includes (A) a soil-only place corresponding to a mud (hereinafter referred to as “soil”), (B) a place where a thin ballast is laid on the soil (“thin bed”), (C) )
It consists of three locations: a thick ballast on the soil ("thick ballast"). The "thin track" had a ballast thickness of about 250 mm, and the "thick track" had a ballast thickness of about 430 mm. Further, actual sleepers used for railway tracks were partially buried in the “thin trackbed” and the “thick trackbed”.

FIG. 3 is a diagram showing the results of a basic test according to the present invention. In this example, the track bed inspection apparatus 10 according to the present invention shown in FIG. It is the result of having measured the pressure level using the sound level meter. Note that the characteristics of the sound level meter include an "A characteristic" in which weighting is performed so that the noise level can be directly read from the indicated value of the sound level meter, and a "C characteristic" in which the weighting is small and the characteristic is flat. (A) of FIG.
Shows the measurement result based on the A characteristic, and (B) shows the measurement result based on the C characteristic.

In FIG. 3 (A), for comparison, pavement (drainable pavement and dense-grained pavement), sound absorbing material, and reflecting material (for example, concrete) are also reflected under the same conditions in addition to the test roadbed described above. The sound pressure level of the sound was measured. From this figure,
The sound absorption rate of the mud (soil) is low, and the sound pressure level of the reflected sound becomes a high value close to the pavement road. Conversely, the sound absorption rate of the ballast ballast is high (close to the sound absorbing material), It can be seen that the pressure level is lower. But on the other hand, "soil"
Comparing the sound pressure levels of the reflected sound in the “thin ballast” and the “thin ballast”, it was found that the relationship between the thickness of the ballast and the sound pressure level could not be found from FIG.

On the other hand, in FIG. 3B based on the C characteristic, when there is no sleeper, the noise level decreases in the order of “soil”, “thin track”, and “thick track”, and It can be seen that when there is a mud below, the sound pressure level (C characteristic) of the reflected sound decreases almost in inverse proportion to the thickness of the ballast. Therefore, by analyzing the sound pressure level of the reflected sound using the frequency characteristic of the C characteristic, it is possible to inspect the state of the roadbed mud.

3 (A) and 3 (B), when there is a sleeper, a constant relationship between the thickness of the ballast and the sound pressure level cannot be found in any case, and the influence of the sleeper can be avoided. It was found that it was necessary to measure.

FIGS. 4A and 4B are diagrams showing the results of a basic test of the present invention. FIG. 4A shows the sound pressure level of the reflected sound due to the C characteristic in the frequency range of 50 to 5000 Hz, and FIG. This is a result of frequency analysis in a frequency range of up to 400 Hz. From these figures, in the frequency range of 160 to 315 Hz (indicated by a double arrow), the noise level decreases in the order of “soil”, “thin track”, and “thick track”,
It can be seen that the thickness of the ballast can be checked from the decrease in the sound pressure level of the reflected sound. Note that this relationship was not clearly obtained in a frequency range of 125 Hz or less and a frequency range of 400 Hz or more.

FIGS. 5A and 5B are still another views showing the results of the basic test of the present invention. FIG. 5A shows the sound pressure level of the reflected sound due to the A characteristic in the frequency range of 50 to 5000 Hz, and FIG. Similarly, frequency analysis is performed in a frequency range of 125 to 400 Hz. From these figures, as in FIG. 4, in the frequency range of 160 Hz to 315 Hz (indicated by a double arrow), the noise level decreases in the order of “soil”, “thin track”, and “thick track”. It can be seen that the ballast thickness can be inspected from the decrease in the sound pressure level of the reflected sound. Note that FIG. 5 shows the same relationship even at 125 Hz,
This relationship was not clearly obtained in the frequency range above z.

According to the above-described apparatus and method of the present invention, a fixed-level sound wave is radiated from the speaker 12 to the ballast 3 and the reflected sound is converted into a sound pressure signal by the microphone 14, and further a sound pressure level analyzer. By converting the sound pressure level into the sound pressure level by the use of the ballast 16, the sound pressure level of the reflected sound from the ballast 3 can be analyzed. Therefore, based on the results of the above-described basic test, the position of the mud under the ballast is estimated in a non-contact manner from the degree of the decrease in the sound pressure level of the reflected sound, and the state of the ballast is diagnosed and inspected. be able to. The degree of the decrease in the sound pressure level of the reflected sound is calibrated using the results of preliminary tests performed in advance and using concrete, mud or equivalent soil, ballast in a normal state in advance, etc. It is preferable to use the sound pressure level of the reflected sound from the microphone as the reference sound pressure level.

It should be noted that the present invention is not limited to the above-described embodiment, and it goes without saying that various changes can be made without departing from the spirit of the present invention.

[0040]

As described above, according to the apparatus and method for inspecting the state of a ballast bed of the present invention, a ballast ballast can be inspected in a non-contact manner. In addition, since the state of the roadbed can be continuously measured in a non-contact manner by the measuring means using sound, the ballast can be inspected while traveling. Further, according to the configuration of the present invention, it is also possible to avoid the influence of the sleepers and accurately inspect only the ballast ballast in a non-contact manner. Further, the roadbed mud condition inspection apparatus and method according to the present invention can greatly reduce the measurement time, and can save labor compared to the conventional manual operation.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a first embodiment of a roadbed mud condition inspection apparatus according to the present invention.

FIG. 2 is a configuration diagram showing a second embodiment of a roadbed mud condition inspection apparatus according to the present invention.

FIG. 3 is a diagram showing a basic test result of the present invention.

FIG. 4 is another diagram showing a basic test result of the present invention.

FIG. 5 is still another diagram showing the results of the basic test of the present invention.

FIG. 6 is a schematic sectional view of a conventional railway track.

[Explanation of symbols]

 Reference Signs List 1 rail 2 sleepers 3 crushed stone (ballast) 4 mudstone 10 roadbed muddy state inspection device 11a DAT 11b amplifier 12 speaker 14 microphone 16 sound pressure level analyzer 16a sound pressure gauge 16b data recorder 16c analyzer 16d computer 17 wheels 18 sound measurement case 18a Opening 18b Reflector 19 Sound absorbing material 20 Skirt member 22 Sleeper sensor 23 Measurement position sensor 24 Shielding plate

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2D057 CB00 2G047 AA10 BA03 BC00 BC03 BC04 CA07 EA09 EA16 GG27

Claims (10)

[Claims] A speaker for radiating a sound wave in an audible frequency range to a ballast, a microphone for converting a sound reflected by the ballast into a sound pressure signal, A sound pressure level analyzer (16) for converting a pressure signal into a sound pressure level, wherein the state of the bed material is inspected from the sound pressure level of the reflected sound. 2. The method according to claim 1, wherein the sound pressure level of the reflected sound is analyzed by the sound pressure level analyzer based on a frequency characteristic of a C characteristic, and a state of the bed mud is inspected from a difference from a reference sound pressure level. The roadbed mud condition inspection device according to claim 1. 3. The sound pressure level analyzer according to claim 1, wherein:
The roadbed mud condition inspection apparatus according to claim 1, wherein the sound pressure level of the reflected sound in the 315 Hz frequency range is frequency-analyzed, and the state of the bedded muddy state is inspected from the difference from the reference sound pressure level. 4. A sound-measuring case (18) containing the speaker and the microphone, wherein a lower surface of the sound-measuring case has an opening (18a) for covering only a ballast between adjacent sleepers. The roadbed mud condition inspection apparatus according to claim 1, wherein: 5. A sound absorbing material (1) on an inner surface of the sound measuring case.
The track bed mud condition inspection device according to claim 4, wherein 9) is attached. 6. The trackbed according to claim 4, further comprising a flexible and sound-insulating skirt member (20) surrounding the opening between the lower surface of the sound measuring case and the ballast ballast. Mud condition inspection device. 7. The sound measurement case according to claim 4, wherein the sound measurement case has no parallel surface with the ballast ballast and is configured to prevent a sound source of a speaker from directly entering the microphone. Road bed mud condition inspection equipment. 8. The roadbed mud condition inspection apparatus according to claim 1, wherein the speaker emits intermittently short-time acoustic waves between sleepers. 9. A sleeper sensor (2) for detecting a position of a sleeper.
The roadbed mud condition inspection device according to claim 8, further comprising (2). 10. A sound wave in an audible frequency range is radiated to a ballast, a sound reflected by the ballast is converted into a sound pressure signal, and the sound pressure signal is converted into a sound pressure level. A method for inspecting the state of a bedbed mud, which inspects the state of a bedbed mud from a pressure level.