A continuous mobile seismic wave picking method and device

Abstract

The present invention discloses a method and device for continuous mobile seismic wave pickup. The array-type vibration sensing device of the device includes a plurality of microphones, which are evenly and symmetrically arranged in two rows on a fixed frame along the travel direction of the survey line; a hammer hole is provided in the middle of the two rows of microphones, and a hammer device passes through the hammer hole to hammer the plane to be measured to generate an excitation signal; each microphone receives a knocking point signal, and a seismic wave pickup method is used to process the recorded signal. The method performs segmented signal acquisition on the signal sampling points through an array-type microphone, and performs offset point calculation, compensation and diffraction superposition processing on each segment of the signal, and finally splices each segment of the processed signal in sequence to obtain the signal of the current hammer point. The present invention can overcome the problem of receiving point dislocation caused by the use of non-contact coupling microphones in the continuous acquisition process to improve the detection efficiency, and the use of multiple microphones for receiving and processing can effectively improve the signal-to-noise ratio and resolution, and ensure the signal quality.

Description

Technical Field

[0001] The present invention relates to the field of seismic survey technology, and in particular to a seismic wave picking method and device, and is particularly suitable for non-destructive detection of hidden dangers or defects inside concrete structures or steel structures. Background Art

[0002] Whether it is due to errors in the early construction process or after a period of use, the internal medium structure of the concrete structure or steel structure will have varying degrees of damage, and there may be hidden dangers such as voids, cracks, and looseness. If not promptly managed, later factors such as rain erosion will further aggravate the hidden dangers, and then seriously threaten the surrounding components of the medium structure, causing property losses and safety accidents.

[0003] At present, the detection technologies for concrete structures or steel structures include geological radar, ultrasonic method and seismic wave method. Among them:

[0004] (1) The geological radar method has high operating efficiency, but because its detection of abnormal reactions is based on the electrical parameters of the medium, it is limited by metal medium structures such as concrete structures or steel bars inside and outside steel structures. The emitted electromagnetic waves will be reflected multiple times, resulting in inaccurate detection results and misjudgment.

[0005] (2) The ultrasonic method has high requirements for coupling conditions. It is easy to lose and scatter in the air, and needs to be coupled with common butter or water. However, when faced with large-scale inspection projects, a large amount of coupling agent needs to be prepared when carrying out the operation, which makes the detection work complicated.

[0006] (3) The traditional seismic wave method uses seismic wave excitation, which can effectively detect hidden defects under medium structures such as concrete structures or steel structures. However, to achieve a single transmission and reception, the receiving detector needs to be stably placed on the surface to be tested, the shot point is struck, the signal collection is completed, and then the shot point and the receiving point are moved to the next hammer point at the same time, and the previous actions are repeated until the detection end. Combined with actual working conditions, the traditional seismic operation method has low detection efficiency and is more suitable for detailed inspection of concrete structures or steel structures.

[0007] If the traditional seismic wave detection system can be combined with the continuous acquisition system to achieve continuous acquisition, the operating efficiency will be greatly improved. For example, Chinese patent document CN103245968A discloses a rolling motion sensor device and its use method, in which the sensor is mounted and fixed on the axle of the rolling wheel, the sensor points to the coupling direction and moves on the surface of the medium together with the rolling wheel; the sensor is indirectly coupled to the surface of the medium being driven through the axle surface, and the vibration signal is transmitted and coupled to the sensor mounted on the rolling shaft. The seismic source and the rolling wheel continue to move forward at the same time, and the vibration signal acquisition instrument completes the sequential acquisition of seismic exploration records on the surface of the medium, and the sequential acquisition records form a seismic arrangement, and the seismic arrangement records are used to detect and identify hidden dangers under the surface of the rolling medium. The sensor maintains the coupling direction of the sensor installation during movement, and realizes continuous vibration signal acquisition during rolling forward, which is suitable for continuous detection of roadbed hidden dangers or concrete structure quality.

[0008] Based on the above system, using an air-based sensor device to replace the contact detector can realize a continuous acquisition system, but there is still a problem in the detection process: the problem of inconsistency between the striking point and the receiving point. When the hammering device completes the hammering at a certain point, the hammering device and the air-based sensor device are in a forward motion state, causing the air-based sensor device to deviate from the top of the hammering point, resulting in a deviation in the received signal.

[0009] Therefore, it is of great significance to develop a method and device that can reliably and stably pick up the original striking point signal after hammering, and to carry out continuous and efficient detection of concrete structures or steel structures with a seismic wave continuous acquisition system. Summary of the invention

[0010] The technical problem to be solved by the present invention is to provide a continuous mobile seismic wave picking method and device. Its purpose is to solve the problem that the hammer device and the array vibration sensor device are in motion during the continuous detection process, which may cause the receiving point to be misaligned. The array microphone is used to collect the signal sampling points in segments, and each segment of the signal is processed by offset point calculation, compensation and diffraction superposition to correct the inconsistency of the sending and receiving points, thereby obtaining the current hammer point signal.

[0011] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0012] In a first aspect, the present invention provides a continuous mobile seismic wave picking method, which specifically comprises the following steps:

[0013] S1. Parameter selection: The pickup device is provided with two parallel and symmetrically arranged microphones along the measuring line. The position of the hammer point and the number of microphones required for diffraction superposition, 2M, are selected on the device. Specifically, M microphones are selected from each column for diffraction superposition and are numbered 1 to M in sequence. The hammer point is located on the midline of the two columns of microphones; the center distance between two adjacent microphones in each column is a and equal, the center distance between the two parallel columns of microphones is b, and the height between the bottom surface of each microphone and the detection surface is h; the number of signal sampling points of the host computer is set to S, and is evenly divided into F segments, and the number of sampling points in each segment is P;

[0014] S2, microphone group corresponding: the continuous acquisition system moves along the measurement line at a preset speed. The first segment of the sampling points S in step S1 is obtained by processing the signals received by microphones numbered 1 to M, the second segment corresponds to the signals received by microphones numbered 2 to M+1, and so on. The F segment corresponds to the signals received by microphones numbered F to M+F-1, and each segment implements the following steps S4, S5, S6, and S7 respectively;

[0015] S3, calculation of the starting point number: calculating the starting point number H corresponding to the hammering point directly above the hammering point;

[0016] S4. Distance calculation: Calculate the distance R from the 2M microphones above the hammer point to the hammer point i ;

[0017] S5, offset point calculation: Calculate the offset point number Q of the 2M microphones mentioned in step S3 relative to the top of the hammering point i ;

[0018] S6. Compensation coefficient calculation: Calculate the compensation coefficient Compensation coefficient is the distance R from the microphone to the hammer point i The ratio of the square of to the square of h;

[0019] S7, diffraction superposition: perform diffraction superposition processing on the current signal;

[0020] S8, signal splicing: After all signal segments 1 to F are processed, each segment is spliced ​​in sequence to obtain the current hammer point signal.

[0021] Further, in step S3, the starting point number H corresponding to the hammering point directly above the hammering point is calculated according to the following formula;

[0022] H = h / v2 / u;

[0023] In the formula, v2 is the propagation speed of sound waves in the air; u is the sampling interval set by the host computer; and h is the height between the bottom surface of the microphone and the detection surface.

[0024] Further, in step S4, the distance R from the 2M microphones above the hammering point to the hammering point is calculated according to the following formula: i ;

[0025] When the number of microphones M is an odd number,

[0026] When the number of microphones M is an even number,

[0027] In the formula, i is the microphone number, f is the signal segment number; both numbers i and M+2f-i-1 include two parallel and symmetrically arranged columns, R i R is the distance from the microphone head numbered i to the hammer point, M+2f-i-1 It is the distance from the microphone head numbered M+2f-i-1 to the hammer point.

[0028] Further, in step S5, the number of offset points Q of the 2M microphones relative to the top of the hammering point is calculated according to the following formula: i ;

[0029] Q i , Q M+2f-i-1 =(R i / v2-h / v2) / u;

[0030] In the formula, Q i Q is the number of points that the microphone head numbered i is offset from the point directly above the hammering point. M+2f-i-1 It is the number of offset points of the microphone numbered M+2f-i-1 relative to the point directly above the hammering point. Both numbers i and M+2f-i-1 include two columns arranged in parallel and symmetrically.

[0031] Specifically, in step S6, the compensation coefficient is the distance R from the microphone to the hammer point i The ratio of the square of to the square of h; that is, the compensation coefficient It is expressed as:

[0032]

[0033] Furthermore, in step S7, the calculation formula for the diffraction superposition processing is:

[0034]

[0035] In the formula, D i is the data collected by the corresponding numbered microphone; k is the number of points in this signal, 1≤k≤P.

[0036] Further,

[0037] In step S5, when the calculated number of offset points is a decimal, linear or nonlinear interpolation is performed on the current channel signal.

[0038] Further,

[0039] Ensure that each signal segment has 2M microphones when performing superposition offset.

[0040] Preferably, the number of M is an odd number of 5, or an even number of 4 or 6.

[0041] Further,

[0042] When the microphones with the same number in two columns are not located directly above the hammering point, a linear interpolation or nonlinear interpolation method is used to obtain the signal value directly above the hammering point.

[0043] In a second aspect, the present invention provides a continuous mobile seismic wave pickup device, comprising a fixed frame, an array-type vibration sensor device and a hammer device; wherein:

[0044] The array-type vibration sensor device comprises a plurality of microphones arranged on the fixed frame, and the plurality of microphones are evenly arranged in two parallel rows along the direction of travel of the measuring line on the fixed frame, and the total number of microphones of the device is greater than the number of microphones required for diffraction superposition, 2M; each microphone is connected to the host computer through a signal line;

[0045] The fixing frame is provided with a hammer hole at the middle position of the two rows of microphones, and the hammer device passes through the hammer hole to hammer the plane to be measured to generate an excitation signal;

[0046] The pickup device is mounted on a continuous acquisition system. When the hammer device hammers the plane to be measured, each microphone in the array vibration sensor device receives the knocking point signal during the continuous acquisition movement, and the above-mentioned continuous mobile seismic wave pickup method is used to process the recorded signal.

[0047] Preferably, the number of microphones is not less than 20, and the number of microphones in each column is not less than 10.

[0048] Further,

[0049] The microphones are evenly and parallelly arranged in two rows in a straight line along the measuring line direction, and the center distance a between two adjacent microphones in each row is equal.

[0050] Further,

[0051] The microphone is an acoustic-electric transducer. Furthermore, the acoustic-electric transducer is an electric sensor, a capacitive sensor, a piezoelectric sensor, an electromagnetic sensor, etc.

[0052] Further,

[0053] The receiving surface of the microphone is spherical and omnidirectional, and can receive vibration signals from all directions.

[0054] Further,

[0055] The microphones of the array-type vibration sensor device are detachably arranged on a fixed frame, and the center distance a between adjacent microphones and the number of microphones can be adjusted according to actual conditions to adopt the best mode to cooperate with the seismic wave continuous acquisition system, with strong applicability and practicality.

[0056] The present invention has the following beneficial effects:

[0057] 1. The present invention provides a continuous mobile seismic wave picking method and device. The picking device provided by the present invention includes a fixed frame, an array-type vibration sensor device and a hammering device. The array-type vibration sensor device includes a plurality of microphones, and the plurality of microphones are arranged in two parallel and symmetrical rows on the fixed frame along the travel direction of the survey line; a hammering hole is provided between the two rows of microphones, and the hammering device penetrates the hammering hole to hammer the plane to be measured to generate an excitation signal; each microphone receives the knocking point signal, and the recorded signal is processed by the seismic wave picking method. The method performs segmented signal acquisition on the number of signal sampling points through an array-type microphone, and calculates, compensates and processes each segment of the signal through the offset point number, and finally splices each segment of the processed signal in sequence to obtain the signal of the current hammering point. The present invention can overcome the problem of receiving point dislocation caused by the use of non-contact coupling microphones to improve detection efficiency in the continuous acquisition process, and correct the problem of inconsistent sending and receiving points. The device uses multiple microphones to receive and process, which can effectively improve the signal-to-noise ratio and resolution, and ensure signal quality.

[0058] 2. The continuous mobile seismic wave picking method and device provided by the present invention can realize continuous data collection by cooperating with the seismic wave continuous acquisition system, and can solve the problem of received signal deviation caused by the inconsistency between the knocking point and the receiving point during the continuous acquisition process.

[0059] 3. The continuous mobile seismic wave picking method and device provided by the present invention are suitable for hidden dangers inside planar medium structures, especially for non-destructive detection of hidden dangers or diseases inside concrete structures or steel structures. It can realize continuous operation, has a simple device structure, is easy to operate, and has high detection efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 It is a schematic diagram of the structure of a seismic wave array pickup device according to an embodiment of the present invention.

[0061] Figure 2 It is a schematic diagram of the flow of the continuous mobile seismic wave array picking method according to an embodiment of the present invention.

[0062] Figure 3Schematic diagram of the working principle of an embodiment of the present invention, wherein 3(1) is a schematic diagram of the principle of the initial state (first signal segment); 3(2) is a schematic diagram of the principle of the second signal segment; 3(3) is a schematic diagram of the principle of the third signal segment; 3(4) is a schematic diagram of the principle of the fourth signal segment.

[0063] Figure 4 Schematic diagram of actual sampling signals in an embodiment of the present invention.

[0064] Figure 5 4 is a signal diagram of the hammering point in an embodiment of the present invention. DETAILED DESCRIPTION

[0065] In order to make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0066] Example

[0067] Reference Figure 1 The present embodiment provides a continuous mobile seismic wave pickup device, including a fixed frame 1, an array-type vibration sensor device, and a hammer device 4; wherein: the array-type vibration sensor device includes a plurality of microphones 3 arranged on the fixed frame 1, and the plurality of microphones 3 are arranged in two parallel rows symmetrically and evenly along the travel direction of the measuring line on the fixed frame 1; each microphone 3 is connected to the host computer through a signal line 2; a hammer hole 5 is provided in the middle position of the two rows of microphones 3 on the fixed frame 1, and the hammer device 4 passes through the hammer hole 5, and is used to hammer the plane 6 to be measured to generate an excitation signal.

[0068] The number of microphones 3 is not less than 20, and the number of microphones in each column is not less than 10. In this embodiment, the number of microphones is 24, and there are 12 microphones in each column.

[0069] The microphones 3 are arranged in parallel and uniformly in two rows in the shape of a straight line along the measuring line, and the center distance a between two adjacent microphones in each row is equal. The microphones 3 are acoustic-electric converters. In specific implementation, the acoustic-electric converters are electric sensors, capacitive sensors, piezoelectric sensors, electromagnetic sensors, etc.

[0070] In order to receive vibration signals from all directions, the receiving surface of the microphone 3 is spherical and omnidirectional.

[0071] The microphone 3 of the array-type vibration sensor device is detachably arranged on the fixed frame 1. The center distance a of adjacent microphones is adjusted according to actual conditions, and the number of microphones is increased or decreased to adopt the best mode to cooperate with the seismic wave continuous acquisition system to improve the applicability and practicality of the device.

[0072] In the specific working process, the picking device is mounted on the continuous acquisition system. When the hammering device hammers the plane to be measured 6, such as a medium structure plane such as a concrete structure or a steel structure, each microphone 3 in the array vibration sensor device receives the knocking point signal during the continuous acquisition movement, and the following continuous mobile seismic wave picking method is used to process the recorded signal.

[0073] During the movement of the continuous acquisition system, at the moment when the hammer device hammers the plane to be measured, the acquisition trigger device will obtain the synchronization signal of the hammer time, and at the same time transmit this synchronization signal to the continuous acquisition system. The continuous acquisition system collects the signal from the seismic wave pickup device of the embodiment of the present invention.

[0074] like Figure 2 As shown, the continuous mobile seismic wave picking method provided in this embodiment includes the following steps:

[0075] S1. Parameter selection: Select the position of the hammer point and the number of microphones 2M required for diffraction superposition on the pickup device. Specifically, select M microphones from each column for diffraction superposition, and each column is numbered 1 to M along the direction of the measurement line. The hammer point is located on the midline of the left and right columns of microphones; the center distance between two adjacent microphones in each column is a and equal, the center distance between the two parallel columns of microphones is b, and the height between the bottom surface of each microphone and the detection surface is h; set the number of signal sampling points of the host computer to S, and divide it into F segments, with P sampling points in each segment.

[0076] The number M of the diffraction superposition microphones can be an odd number or an even number, and the corresponding calculation method is different. The value is usually an odd number of 5, an even number of 4 or 6.

[0077] S2, microphone group corresponding: the continuous acquisition system moves along the survey line at a preset speed v1. The first section of the sampling points S in step S1 is obtained by processing the signals received by the microphones numbered 1 to M, the second section is obtained by processing the signals received by the microphones numbered 2 to M+1, ... the Fth section is obtained by processing the signals received by the microphones numbered F to M+F-1, and each section implements the following steps S4, S5, S6, and S7 respectively.

[0078] Specifically, after segmentation, each signal corresponds to 2M microphones. Using multiple microphones to receive and process can effectively improve the signal-to-noise ratio and resolution, and ensure signal quality.

[0079] S3, calculation of the starting point number: Calculate the starting point number H corresponding to the hammering point directly above the hammering point according to the following formula;

[0080] H = h / v2 / u;

[0081] In the formula, v2 is the propagation speed of sound waves in the air; u is the sampling interval set by the host computer; h is the height between the bottom of the microphone and the detection surface; the number of starting signal points H is determined by the height from the bottom of the microphone to the detection surface and the sampling interval set by the host computer.

[0082] S4. Distance calculation: Calculate the distance R from the 2M microphones above the hammer point to the hammer point according to the following formula i ;

[0083] When the number of microphones M is an odd number,

[0084] When the number of microphones M is an even number,

[0085] In the formula, i is the microphone number, f is the signal segment number; both numbers i and M+2f-i-1 include two parallel and symmetrically arranged left and right columns, R i R is the distance from the microphone head numbered i to the hammer point, M+2f-i-1 It is the distance from the microphone head numbered M+2f-i-1 to the hammer point. When i=1, R1 represents the distance from left 1 and right 1 to the hammer point.

[0086] Regardless of whether M is an odd number or an even number, the distances from the symmetrical microphones to the hammering point are equal. For example, when M=5, the first microphone in the left and right columns of microphones are symmetrical to the fifth microphone, and the second microphone is symmetrical to the fourth microphone, and the distances from the hammering point are also equal.

[0087] S5. Calculation of offset points: Further calculate the offset points Q of the 2M microphones relative to the top of the hammering point according to the following formula: i ;

[0088] Q i , Q M+2f-i-1 =(R i / v2-h / v2) / u;

[0089] In the formula, Q i Q is the number of points that the microphone head numbered i is offset from the point directly above the hammering point. M+2f-i-1 It is the number of offset points of the microphone numbered M+2f-i-1 relative to the top of the hammering point. Both numbers i and M+2f-i-1 include two left and right columns that are symmetrically arranged in parallel.

[0090] In the process of calculating the offset point in step S5, the calculation result may be a decimal. In this case, linear interpolation or nonlinear interpolation may be performed on the signal received by the corresponding microphone to obtain a corresponding value.

[0091] S6. Compensation coefficient calculation: The compensation coefficient is further calculated by the following formula

[0092]

[0093] Compensation coefficient is the distance R from the microphone to the hammer point i The ratio of the square of to the square of h;

[0094] S7, Diffraction superposition: Perform diffraction superposition processing on the current signal, and the calculation formula is:

[0095]

[0096] In the formula, D i is the data collected by the corresponding numbered microphone; k is the number of points in this section of the signal, 1≤k≤P;

[0097] S8, signal splicing: After all signal segments 1 to F are processed, each segment is spliced ​​in sequence to obtain the current hammer point signal.

[0098] During the operation of the continuous data acquisition system, when the microphones with the same number in two columns are not located directly above the hammering point, a linear interpolation method or a nonlinear interpolation method can be used to obtain the signal value directly above the hammering point.

[0099] The meanings of the symbols in the formulas of the present invention are as follows:

[0100] Table 1 The meanings of the symbols in the formulas

[0101]

[0102] Specifically, in order to better understand the scheme and working principle of the present invention, Figure 3 This is a continuous mobile seismic wave picking method according to an embodiment of the present invention. And further explained in conjunction with this principle diagram, specifically, the center distance between adjacent microphones a=5.12cm, the height between the bottom surface of the microphone and the detection surface h=10cm, the sampling interval u=50μs set by the host computer, the number of sampling points S=8192 points, the propagation speed of sound waves in the air medium v2=340m / s, the parallel distance between two rows of microphones b=4cm, and in this embodiment, the number of microphones required for each column of diffraction superposition is M=5, then the hammer point is located directly below the middle of the left 3 microphones and the right 3 microphones. Divide the number of sampling points S into 8 sections evenly, then F=8, P=1024. The microphone number directly above the hammer point and the corresponding superimposed offset microphone number and the final number of signal points are shown in Table 2 below:

[0103] Table 2 Correspondence between the microphone number directly above the hammer point and the corresponding superimposed offset microphone number and the final signal point number

[0104]

[0105] Note: The numbers in the table include both left and right columns.

[0106] like Figure 3 (1) As shown in the schematic diagram, it is the initial state. The hammer point is located directly below the middle of the microphones numbered left 3 and right 3. The ten microphones above the hammer point, from left 1 to left 5, and right 1 to right 5, are superimposed and offset to obtain the values ​​of the points numbered 1 to 1024 (that is, the first signal segment). The hammer point position remains unchanged, and the continuous acquisition system moves in the direction of the survey line, such as Figure 3 (2) As shown in the schematic diagram, at this time, the ten microphones from left 2 to left 6 and right 2 to right 6 above the hammer point are superimposed and offset to obtain the values ​​of the 1025th to 2048th sequence points (that is, the second signal segment). The schematic diagrams of the third and fourth signal segments are shown as follows: Figure 3 (3) Figure 3 As shown in (4), ... and so on until the last signal segment, the ten microphones from left 8 to left 12 and right 8 to right 12 above the hammer point are superimposed and offset to obtain the values ​​of the 7169th to 8192th serial points.

[0107] Take the first signal segment processing as an example:

[0108] The starting point number of the receiver located just above the hammering point is:

[0109] H=h / v2 / u≈6;

[0110] Calculate the distance R from the 10 microphones above the hammer point (5 in each column) to the hammer point i ;

[0111] Specifically, the left 3 and right 3 microphones are symmetrical about the hammering point, and the distances to the hammering point are equal;

[0112] Similarly, the distances from left 2, left 4, right 2 and right 4 to the hammering point are equal, and the distances from left 1, left 5, right 1 and right 5 to the hammering point are also equal;

[0113]

[0114]

[0115]

[0116] Calculate the number of points where the 10 microphones mentioned above are offset from the hammer point:

[0117] Serial number is 1, 5 (including left and right) microphone offset points:

[0118] Q1=Q5=(R1 / v2-h / v2) / u≈3;

[0119] The number of microphone offset points is 2, 4 (including left and right):

[0120] Q2=Q4=(R2 / v2-h / v2) / u≈1;

[0121] The number of microphone offset points is 3 (including left and right): Q3 = (R3 / v2-h / v2) / u≈1;

[0122] Compensation coefficient calculation, corresponding to the distance R from the microphone to the hammer point i The ratio of the square of to the square of the distance h from the hammer point directly above the hammer point.

[0123]

[0124]

[0125]

[0126] Diffraction superposition: Perform diffraction superposition processing on the current signal. The calculation formula is:

[0127]

[0128] After the 1st to 8th signal segments are all processed according to the above steps, each segment is spliced ​​in sequence to obtain the current hammer point signal.

[0129] Specifically, Figure 4 This is the original signal diagram collected corresponding to a hammering point in this embodiment. Figure 4 The first track is the signal received by the left 1 microphone, the second track is the signal received by the right 1 microphone, the third track is the signal received by the left 2 microphone, the fourth track is the signal received by the right 2 microphone, and so on... It can be seen that the left 3 and right 3 microphones located directly above the hammering point receive the strongest energy. The farther the microphone is from the hammering point, the later it receives the signal from the hammering point and the weaker the energy is.

[0130] Figure 5 The hammer point signal diagram is a diagram of the original signal collected by this embodiment after being processed by the seismic wave picking method. It can be seen that the seismic wave picking method and device provided by the present invention can greatly overcome the limitation of the misalignment of the excitation point and the receiving point caused by the use of non-contact coupling microphones in the continuous collection process to improve the detection efficiency. At the same time, multiple microphones receive and process to effectively improve the signal-to-noise ratio and resolution, and ensure the signal quality. The present invention is particularly suitable for non-destructive detection of hidden dangers or diseases inside concrete structures or steel structures, can realize continuous operation, has a simple device structure, is easy to operate, and has high detection efficiency.

[0131] The above descriptions are only some preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A continuous mobile seismic wave picking method, characterized in that: The specific steps include: S1. Parameter selection: The pickup device is provided with two parallel and symmetrically arranged microphones along the measuring line. The position of the hammering point and the number of microphones required for diffraction superposition 2M are selected on the device. Specifically, M microphones are selected from each column for diffraction superposition and are numbered 1 to M in sequence. The hammering point is located on the midline of the two columns of microphones; the center distance between two adjacent microphones in each column is a and equal, the center distance between the two parallel columns of microphones is b, and the height between the bottom surface of each microphone and the detection surface is h; the number of signal sampling points of the host computer is set to S, and is evenly divided into F segments, and the number of sampling points in each segment is P; S2, microphone group corresponding: the continuous acquisition system moves along the measurement line at a preset speed. The first segment of the sampling points S in step S1 is obtained by processing the signals received by the microphones numbered 1 to M, the second segment is obtained by processing the signals received by the microphones numbered 2 to M+1, and so on. The F segment is obtained by processing the signals received by the microphones numbered F to M+F-1. Each segment implements the following steps S4, S5, S6, and S7 respectively. S3, calculation of the starting point number: calculating the starting point number H corresponding to the hammering point directly above the hammering point; S4. Distance calculation: Calculate the distance from the 2M microphones above the hammer point to the hammer point ; S5, offset point calculation: Calculate the number of offset points of the 2M microphones in step S3 relative to the point directly above the hammering point ; S6. Compensation coefficient calculation: Calculate the compensation coefficient , compensation coefficient The distance from the microphone to the hammer point The ratio of the square of to the square of h; S7, diffraction superposition: perform diffraction superposition processing on the current signal; the calculation formula for diffraction superposition processing is: ； In the formula, The data collected by the corresponding numbered microphone; is the number of points in this signal, ; S8, signal splicing: After all signal segments 1 to F are processed, each segment is spliced ​​in sequence to obtain the current hammer point signal.

2. The continuous mobile seismic wave picking method according to claim 1, characterized in that: In step S3, the starting point number H corresponding to the hammering point directly above the hammering point is calculated according to the following formula; ； In the formula, is the speed of sound waves in air; The sampling interval set for the host computer; It is the height between the bottom of the microphone and the detection surface.

3. The continuous mobile seismic wave picking method according to claim 2, characterized in that: In step S4, the distance from the 2M microphones above the hammer point to the hammer point is calculated according to the following formula: ; When the number of microphones M is an odd number, ; When the number of microphones M is an even number, ; In the formula, i is the microphone number, f is the signal segment number; both numbers i and M+2f-i-1 include two columns arranged in parallel and symmetrically. is the distance from the microphone head numbered i to the hammer point, It is the distance from the microphone head numbered M+2f-i-1 to the hammer point.

4. The continuous mobile seismic wave picking method according to claim 3, characterized in that: In step S5, the number of offset points of the 2M microphones relative to the top of the hammering point is calculated according to the following formula: ; ； In the formula, is the number of points that the microphone head numbered i is offset from the point directly above the hammer strike point. It is the number of offset points of the microphone numbered M+2f-i-1 relative to the point directly above the hammering point. Both numbers i and M+2f-i-1 include two columns arranged in parallel and symmetrically.

5. The continuous mobile seismic wave picking method according to claim 1, characterized in that: In step S5, when the calculated offset point number is a decimal, linear or nonlinear interpolation is performed on the current channel signal; When the microphones with the same number in two columns are not located directly above the hammering point, a linear interpolation or nonlinear interpolation method is used to obtain the signal value directly above the hammering point.

6. A continuous mobile seismic wave pickup device, characterized in that: It includes a fixing frame, an array vibration sensor device, and a hammer device; wherein: The array-type vibration sensor device comprises a plurality of microphones arranged on the fixed frame, and the plurality of microphones are evenly arranged in two parallel rows along the direction of travel of the measuring line on the fixed frame, and the total number of microphones of the device is greater than the number of microphones required for diffraction superposition, 2M; each microphone is connected to the host computer through a signal line; The fixing frame is provided with a hammer hole at the middle position of the two rows of microphones, and the hammer device passes through the hammer hole to hammer the plane to be measured to generate an excitation signal; The pickup device is mounted on a continuous acquisition system. When the hammer device hammers the plane to be measured, each microphone in the array vibration sensor device receives the knocking point signal during the continuous acquisition movement, and the recorded signal is processed by the continuous mobile seismic wave pickup method described in any one of claims 1-5.

7. The continuous mobile seismic wave pickup device according to claim 6, characterized in that: The microphone is an acoustic-electric converter, and the acoustic-electric converter is an electric sensor, a capacitive sensor, a piezoelectric sensor, or an electromagnetic sensor.

8. The continuous mobile seismic wave pickup device according to claim 6, characterized in that: The receiving surface of the microphone is a spherical surface.

9. The continuous mobile seismic wave pickup device according to claim 6, characterized in that: The microphones of the array-type vibration sensor device are detachably arranged on a fixing frame, and the center distance a of adjacent microphones and the number of microphones can be adjusted according to actual conditions.

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