An ultrasonic wave paving thickness detection method and system

Abstract

The application relates to the technical field of paving thickness measurement, in particular to an ultrasonic paving thickness detection method and system, which comprises the following steps: adopting the Akaike information criterion (AIC) for an echo measurement sequence collected from a paved road, obtaining an echo positioning sequence and an echo AIC statistical sequence based on the numerical distribution of AIC values of all elements of the echo measurement sequence; analyzing the element distribution and variation characteristics in the echo positioning sequence and the variation trend of each element in the echo AIC statistical sequence to obtain a signal mutation trend degree; obtaining an echo development trend degree based on the straight line fitting result of each element in the echo AIC statistical sequence; confirming a first echo moment, combining the propagation speed of ultrasonic waves in paving mixture, and calculating the paving thickness. The application aims to improve the accuracy of paving thickness measurement.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of paving thickness measurement, in particular to an ultrasonic paving thickness detection method and system. BACKGROUND

[0002] Paving refers to uniformly laying materials such as asphalt mixture and cement concrete on a roadbed or a lower road surface structure to form a flat and dense road surface layer. The uniformity of paving thickness will directly affect the flatness, bearing capacity and service life of the road. Ultrasonic detection is a non-destructive testing technology that does not cause any damage to the paving layer, can accurately measure the paving thickness in real time, and timely find problems such as uneven thickness. Therefore, ultrasonic technology is widely used in thickness measurement. Secondly, the ultrasonic detection equipment is convenient to operate and can be quickly moved on the construction site to realize continuous measurement, greatly improving the detection efficiency.

[0003] When measuring the paving thickness, the time interval of the echo signals of the upper and lower layers of the paving road is used to calculate the paving thickness. In the identification of the time node, the traditional technology identifies the position of the first echo by threshold. However, the paving is mixed by asphalt mixture and cement concrete, so that the ultrasonic detection is easily disturbed by noise. The traditional method does not fully consider the influence of noise on ultrasonic data, resulting in errors in the identification of the first echo, thereby reducing the measurement accuracy of the paving thickness. SUMMARY

[0004] In view of the above, it is necessary to provide an ultrasonic paving thickness detection method and system to solve the above problems.

[0005] The first aspect of the application provides an ultrasonic paving thickness detection method, which comprises:

[0006] Obtaining all echo signals collected by the measurement point on the paving road to form an echo measurement sequence;

[0007] Using the Akaike information criterion on the echo measurement sequence to obtain the AIC value of each element of the echo measurement sequence; based on the numerical distribution of the AIC values of all elements of the echo measurement sequence, the echo measurement sequence is intercepted to obtain an echo positioning sequence, and the AIC value of each element in the echo positioning sequence is combined to obtain an echo AIC statistical sequence; analyzing the distribution and change characteristics of each element in the local range of the echo positioning sequence to confirm the echo change intensity of each element;

[0008] Analyzing the change trend of each element in the echo AIC statistical sequence, combining the echo change intensity of the elements at the same position in the echo positioning sequence, to obtain the signal mutation trend degree of each element in the echo AIC statistical sequence;

[0009] linear fitting is performed on each element in the echo AIC statistical sequence and all elements before the element, and based on a difference between a result of the linear fitting and the corresponding element, in combination with the signal mutation trend degree, an echo development trend degree of each element in the echo AIC statistical sequence is obtained;

[0010] Based on a numerical distribution of all the obtained echo development trend degrees, a first echo moment is confirmed, and in combination with a propagation speed of the ultrasonic wave in the paving mixture, the paving thickness is calculated.

[0011] The formula model used by the Akaike information criterion is as follows: ; wherein, AICx represents an AIC value of an xth element in the echo measurement sequence; lg() represents a logarithm with 10 as a base; N represents a length of the echo measurement sequence; , Varx represents a variance of the first element to the xth element in the echo measurement sequence, and Varx+1 represents a variance of the x+1th element to the last element in the echo measurement sequence; x represents an element serial number value of the echo measurement sequence.

[0012] The echo positioning sequence is specifically a sequence composed of all elements after a position corresponding to a minimum value of the AIC in the echo measurement sequence.

[0013] The echo change intensity of each element is specifically as follows:

[0014] Based on a first-order difference sequence of the echo positioning sequence, a first-order change sequence of the echo positioning sequence is obtained.

[0015] A preset window is centered on each element of the echo positioning sequence; an absolute value mean of elements of the first-order change sequence in the window corresponding to each element in the echo positioning sequence is positively fused with a variance of all elements in the window corresponding to each element in the echo positioning sequence, to obtain the echo change intensity of each element in the echo positioning sequence.

[0016] The signal mutation trend degree of each element in the echo AIC statistical sequence is specifically as follows:

[0017] Based on a first-order difference sequence of the echo AIC statistical sequence, a first-order change sequence of the echo AIC statistical sequence is obtained.

[0018] A result of positively fusing the echo change intensity of each element in the echo positioning sequence with an element at the same position in the first-order change sequence of the echo AIC statistical sequence is taken as the signal mutation trend degree of each element in the echo AIC statistical sequence.

[0019] The echo development trend degree of each element in the echo AIC statistical sequence is specifically as follows:

[0020] Fitting a straight line to each element and all previous elements in the echo AIC statistical sequence to obtain a fitting straight line of each element, comparing each element with the value on the fitting straight line corresponding to the element to confirm the regular development degree of each element;

[0021] For the echo AIC statistical sequence, the product of the signal mutation trend degree of each element and the element at the same position in the first-order change sequence is calculated, and the negative correlation mapping result of the regular development degree of each element is combined to obtain the echo development trend degree of each element in the echo AIC statistical sequence.

[0022] The regular development degree is specifically the absolute value of the difference between each element and the value on the fitting straight line corresponding to the element.

[0023] The first echo time is specifically the time corresponding to the element with the maximum echo development trend degree in the echo AIC statistical sequence.

[0024] The paving thickness is specifically one half of the product of the propagation speed of the ultrasonic wave in the paving mixture and the time length corresponding to the first echo time.

[0025] In a second aspect, the embodiments of the present application also provide a detection system for ultrasonic paving thickness, which comprises a memory, a processor, and a computer program stored in the memory and running on the processor, and the processor implements the steps of the method according to any one of the preceding aspects when executing the computer program.

[0026] The present application has at least the following beneficial effects:

[0027] 1. The present application accurately locates the position of the first echo by comprehensively analyzing the local fluctuation of the echo signal, the AIC change amplitude and the trend change, effectively solving the measurement error problem caused by the non-uniformity of the paving material in the traditional method. Compared with the traditional threshold recognition method, the measurement accuracy is greatly improved, which can more accurately reflect the actual value of the paving thickness and provide a reliable basis for road construction quality control.

[0028] 2. In the paving thickness measurement process, the present application fully considers the influence of environmental noise and material non-uniformity on the ultrasonic signal. By processing the echo signal through the AIC algorithm, combining difference and straight line fitting technology, the echo signal of the paved road is effectively separated, and noise interference is excluded, so that the measurement result is more stable and reliable. Even in complex construction environment, the paving thickness can be accurately measured.

[0029] 3、The application adopts ultrasonic nondestructive testing technology, does not need to destroy the paving layer, can quickly move and continuously measure on the construction site, greatly shortens the detection time. At the same time, through the automatic signal processing and analysis process, the manual intervention is reduced, the detection efficiency is further improved, the problems such as uneven paving thickness can be found in time, and strong support is provided for construction progress control and quality guarantee. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 A step flow chart of a method for detecting ultrasonic paving thickness provided by an embodiment of the application is provided.

[0031] Figure 2 A flow chart of obtaining echo development trend degree provided by an embodiment of the application. DETAILED DESCRIPTION

[0032] In the description of the embodiments of the application, the words such as "exemplary", "or", "for example" are used to represent an example, illustration or description. Any embodiment or design scheme described as "exemplary" or "for example" in the embodiments of the application should not be interpreted as more preferred or more advantageous than other embodiments or design schemes. Rather, the words such as "exemplary", "or", "for example" are intended to present the relevant concept in a specific manner.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the application belongs. The terms used in the specification of the application are only for the purpose of describing the specific embodiments and are not intended to limit the application.

[0034] In addition, it should be noted that the terms "first", "second" in the application and the drawings are used to distinguish similar objects, and are not used to describe a specific order or sequence. The method disclosed in the embodiments of the application or the method shown in the flow chart includes one or more steps for implementing the method, and the execution order of the steps can be interchanged with each other without departing from the scope of the application, and some steps can also be deleted.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the application belongs.

[0036] The specific scheme of the method and system for detecting ultrasonic paving thickness provided by the application will be specifically described below in combination with the drawings.

[0037] Please refer to Figure 1 , which shows a step flow chart of a method for detecting ultrasonic paving thickness provided by an embodiment of the application. The method comprises the following steps:

[0038] The first step: obtaining all the echo signals collected at each measurement point on the paved road to form an echo measurement sequence.

[0039] An arbitrary measurement point is selected on the paved road, and a coupling agent is applied to the measurement point. In this embodiment, the coupling agent is a water-based ethylene glycol gel. The specific implementer can select a suitable coupling agent according to the specific environment. The ultrasonic transmitter of the ultrasonic measuring instrument is closely attached to the measurement point to exclude the interference of air. Then, the ultrasonic transmitter of the ultrasonic measuring instrument transmits ultrasonic waves to the measurement point on the paved road, and the echo receiver carried by the ultrasonic measuring instrument receives the echo signals reflected by the paved road.

[0040] In this embodiment, the frequency value of the signal transmitted by the ultrasonic measuring instrument is 150 kHz, the transmission duration is 1 ms, and the sampling frequency value of the echo signal is 600 kHz. The collected echo signals are arranged in the order of collection time to obtain an echo signal sequence. In order to avoid data loss caused by the environment and the instrument, the missing data in the echo signal sequence is completed by using the mean interpolation method. The completed echo signal sequence is referred to as an echo measurement sequence. The calculation of the mean interpolation method is a known technology, and the specific calculation steps are not described here.

[0041] The second step: using the Akaike Information Criterion (AIC) to obtain the AIC value of each element of the echo measurement sequence; based on the numerical distribution of the AIC values of all elements of the echo measurement sequence, the echo measurement sequence is truncated to obtain an echo positioning sequence, and the AIC statistical sequence of the echo is obtained by combining the AIC value of each element in the echo positioning sequence; the distribution and variation characteristics of each element in the local range of the echo positioning sequence are analyzed to confirm the echo variation strength of each element.

[0042] When the receiver of the ultrasonic measuring instrument receives the echo signal, the items in the environment will reflect and scatter the ultrasonic signal, so that the ultrasonic signal receiver will receive some noise reflection signals. At the same time, the intensity of these reflection signals is small, and the amplitude of the change is small, so that this part of data is in a steady state. For the echo signal reflected by the paved road, the amplitude value of the echo signal will change with the distance, the overall amplitude of the signal will increase, and the oscillation will be enhanced. However, since the mixed material of the pavement is a non-uniform substance, the road echo signal is confused with the reflection signal in the environment, making it difficult to identify the time of the first echo signal of the paved road.

[0043] Therefore, the echo measurement sequence is taken as the input of the Akaike Information Criterion (AIC), and the output is the AIC sequence of the echo measurement sequence. In this embodiment, the formula model used by AIC is: wherein, represents the AIC value of the xth element of the echo measurement sequence, lg() represents the logarithm with base 10, and N represents the length of the echo measurement sequence, respectively represent the variance of the first element to the xth element and the variance of the x+1th element to the last element in the echo measurement sequence, and x represents the element sequence number value of the echo measurement sequence. According to the algorithm principle of AIC, the minimum value of the element AIC in the echo measurement sequence corresponds to the first echo time in the case of no interference, but due to the existence of noise, the time corresponding to the actual minimum value of AIC is not the first echo time, but the first echo position is the position after the minimum value of AIC. Therefore, the data after the minimum value of AIC in the echo measurement sequence is intercepted to obtain an echo positioning sequence, and the AIC signal data after the minimum value of AIC is intercepted to obtain an echo AIC statistical sequence.

[0044] For the received echo signal of the paved road, the change amplitude of the echo signal in unit time is large, so the echo positioning sequence is taken as the input of the first-order difference algorithm, the output is taken as the linear interpolation input, the last element is completed, and the completed data is taken as the first-order change sequence of the echo positioning sequence. Since the echo signal change has oscillation, the change amplitude has positive and negative, for the convenience of operation, the absolute value of each element in the first-order change sequence of the echo positioning sequence is obtained, and the sequence composed of the absolute values of all elements in the first-order change sequence is taken as the change absolute value sequence of the echo positioning sequence, which is used to represent the amplitude change rate of the echo signal. The calculation of the first-order difference algorithm and the linear interpolation method is a known technology, and the specific calculation steps are not described here.

[0045] Therefore, a window with a length of n is obtained with each element in the echo positioning sequence as the center, the elements in the window are taken as the local amplitude sequence of each element in the echo positioning sequence, and n is taken as 7 in this embodiment. The implementer can adjust the value of n according to the actual situation. It should be noted that the insufficient part is completed by the mean filling method. The change amplitude of the echo signal of the paved road is stronger than that of the noise echo signal, so the local change intensity of the echo signal is different in the two cases. Therefore, the echo change intensity of each element in the echo positioning sequence is calculated. Specifically, the mean value of the elements in the local change sequence of each element in the echo positioning sequence is positively fused with the variance of the local amplitude sequence of each element in the echo positioning sequence to obtain the echo change intensity of each element in the echo positioning sequence. In this embodiment, the multiplication calculation method is used for positively fusing multiple variables.​

[0046] It should be understood that, since the ultrasonic echo signal after the pavement is laid has a large change range in the local area, the mean of all elements in the local change sequence of the corresponding ultrasonic echo signal is large, and the local fluctuation of the ultrasonic echo signal is large, and the variance value of the local amplitude sequence of the corresponding ultrasonic echo signal is large, thereby making the echo change intensity of the ultrasonic echo signal large, indicating that the ultrasonic echo signal is more likely to be the echo signal of the laid road, and the echo change intensity can more accurately locate the position of the first echo, thereby improving the accuracy of the laid thickness measurement.

[0047] The third step is to analyze the change trend of each element in the echo AIC statistical sequence, and combine the echo change intensity of the elements at the same position in the echo positioning sequence to obtain the signal mutation trend degree of each element in the echo AIC statistical sequence.

[0048] Since the AIC local change range of the echo signal of the laid road is larger than that of the noise signal, the echo AIC statistical sequence is taken as the input of the first-order difference algorithm, and the output is taken as the input of the linear interpolation, the last element is completed, and the completed data is taken as the first-order change sequence of the echo AIC statistical sequence, which is used to highlight the local features at the position of the first echo of the signal, thereby calculating the signal mutation trend degree of each element in the echo AIC statistical sequence. Specifically, the result of the forward fusion of the echo change intensity of each element in the echo positioning sequence and the elements at the same position in the first-order change sequence of the echo AIC statistical sequence is taken as the signal mutation trend degree of each element in the echo AIC statistical sequence. In this embodiment, the multiplication calculation method is used for forward fusion between variables.

[0049] It should be understood that, since the echo signal change intensity caused by the laid road is large, the echo change intensity is large, and the AIC signal value of the laid road is also large, so that the signal mutation trend degree of the elements in the echo AIC signal is large. The larger the signal mutation trend degree of the elements in the echo AIC signal, the more likely the corresponding echo signal is the laid road echo data, and the more likely the point is the position of the first echo signal of the laid road surface. By accurately obtaining the first echo data, the accuracy of the laid road thickness measurement can be improved.

[0050] The fourth step is to perform linear fitting on each element and all previous elements in the echo AIC statistical sequence, and based on the difference between the linear fitting result and the corresponding element, the signal mutation trend degree is combined to obtain the echo development trend degree of each element in the echo AIC statistical sequence.

[0051] The signal mutation trend degree of the echo AIC statistical sequence element is used to reflect the local maximum convex inflection point feature at the echo position. However, the signal mutation trend degree is calculated by using the first-order change sequence of the echo AIC statistical sequence, so that the calculation result will have difference interference, which causes the deviation of the calculation result. Therefore, the difference interference needs to be excluded. Before the position of the first echo of the road paving, it is the echo data formed by the reflected ultrasonic wave of the paving road. For the echo data of the paving road, the change of the AIC data is a regular change. Therefore, each element in the echo AIC statistical sequence and all previous elements are taken as the input of the linear least square method, and the output is the fitting straight line of each element, and the numerical difference between each element and the value on the fitting straight line is calculated, which is recorded as the regular development degree of each element, which is used to represent the change state of the AIC signal data. Note that the fitting straight line of the first element and the second element is the same. The calculation of the linear least square method is a known technology, and the specific calculation steps are not described here. The numerical difference is obtained by using the calculation method of the absolute value of the difference.

[0052] The echo development trend degree of each element in the echo AIC statistical sequence is calculated. Specifically, for the echo AIC statistical sequence, the product of the signal mutation trend degree of each element and the element at the same position in the first-order change sequence is calculated, and the negative correlation mapping result of the regular development degree of each element is positively fused to obtain the echo development trend degree of each element in the echo AIC statistical sequence. In this embodiment, the product of the kth element is recorded as , and the regular development degree of the kth element is recorded as . The formula of the echo development trend degree of the kth element is: ; in the formula, , which represents a preset parameter for preventing the denominator from being 0, and the value is 0.1 in this embodiment.

[0053] The flowchart of obtaining the echo development trend degree is shown in Figure 2 .

[0054] It should be understood that when the signal mutation trend degree of an element is high, it indicates that there may be significant signal change characteristics at the position corresponding to the element, so a higher weight should be given to it. At the same time, if the regular development degree of the element is strong, that is, the deviation of the previous element from the linear fitting straight line is small, which indicates that the signal change regularity of the element is high and the abnormal information is less. At the same time, when the position does not exceed the position of the first echo, the fluctuation intensity between the data is large, and the AIC signal value is large. At this time, the echo development trend degree of the position is larger. Therefore, the echo development trend degree can accurately reflect the actual change characteristics of the ultrasonic signal of the road paving, so as to realize high-precision identification of the echo signal characteristics.

[0055] Fifth step: based on the obtained numerical distribution of all echo trend degrees, confirming the first echo time, combining the propagation speed of ultrasonic wave in the paving mixture, calculating the paving thickness.

[0056] Arranging all echo trend degrees according to the order of their corresponding elements in the echo AIC statistical sequence, obtaining the echo trend sequence. Since the difference between the ultrasonic echo signal and the environmental reflection signal of the pavement paving is different, the ultrasonic echo signal has a certain trend change, therefore, obtaining the maximum value in the echo trend sequence; taking the maximum value corresponding element time in the echo AIC statistical sequence as the first echo time, recorded as t, then the road paving thickness is , wherein B represents the road paving thickness, since the ultrasonic wave transmission is a reciprocating action, the first echo time is the time of transmitting twice the paving thickness, therefore, it needs to be divided by 2, V represents the propagation speed of ultrasonic wave in the paving mixture, the measurement method is a known technology, the specific calculation steps are not described here, in this embodiment, the value is 4348 m / s.

[0057] Thus, a method for detecting the ultrasonic paving thickness is realized.

[0058] Based on the same inventive concept as the above method, the embodiments of the present application also provide a detection system for ultrasonic paving thickness, comprising a memory, a processor and a computer program stored in the memory and running on the processor, the processor executes the computer program to realize the steps of any one of the above methods.

[0059] The computer program product of the present application can be a computer program implemented on one or more computers. The program instructions can be stored on a computer-readable medium, such as a floppy disk, CD-ROM, and the like. The computer program product can also include computer programs that are transmitted over a network via, for example, telephone line, LAN, wireless instrument, or others. Accordingly, the computer program product of the present application can be an article of manufacture including a computer usable medium having computer readable program code means distributed therein. The computer readable program code means is means for causing a computer to operate in a specific and predefined manner. The present application can also be embodied in a computer readable medium including transitory signals. Accordingly, the present application can be a product, an article of manufacture, and / or a machine. The present application can also be embodied in any computer readable medium for use in

[0060] It is apparent that a person skilled in the art can make various modifications to the application described in the foregoing embodiment, without departing from the spirit and scope of the application. Therefore, the above-described embodiments of the application are intended to be illustrative only and not restrictive. Any modification of the described embodiments, or any replacement of some of the technical features thereof, does not cause the corresponding technical solution to deviate from the scope of the technical solutions of the embodiments of the application, and should be included in the protection scope of the application.

Claims

1. A method for detecting the thickness of ultrasonic paving, characterized in that, The method includes the following steps: All echo signals collected from measurement points on the paved road are acquired and combined to form an echo measurement sequence; The Akaike Information Criterion was applied to the echo measurement sequence to obtain the AIC value of each element in the echo measurement sequence. Based on the numerical distribution of the AIC values ​​of all elements in the echo measurement sequence, the echo measurement sequence was truncated to obtain the echo location sequence. Combined with the AIC value of each element in the echo location sequence, the echo AIC statistical sequence was obtained. The distribution and variation characteristics of each element in the echo location sequence within the local range were analyzed to confirm the echo variation intensity of each element. By analyzing the changing trend of each element in the echo AIC statistical sequence and combining it with the echo change intensity of elements at the same position in the echo localization sequence, the signal abrupt change trend degree of each element in the echo AIC statistical sequence is obtained. A straight line is fitted to each element in the echo AIC statistical sequence and all elements preceding it. Based on the difference between the straight line fitting result and the corresponding element, and combined with the signal abrupt change trend degree, the echo development trend degree of each element in the echo AIC statistical sequence is obtained. Based on the numerical distribution of all obtained echo development trends, the moment of an echo is determined, and the paving thickness is calculated by combining the propagation speed of ultrasonic waves in the paved mixture. The formula model used in the Akaike Information Criterion is as follows: ;in, represents the AIC value of the x-th element in the echo measurement sequence; lg() represents the logarithm to the base 10; N represents the length of the echo measurement sequence; , These represent the variances from the first element to the xth element and from the (x+1)th element to the last element in the echo measurement sequence, respectively; x represents the element index value in the echo measurement sequence.

2. The method for detecting the thickness of ultrasonic paving as described in claim 1, characterized in that, The echo positioning sequence is specifically a sequence consisting of all elements following the position corresponding to the minimum AIC value in the echo measurement sequence.

3. The method for detecting the thickness of ultrasonic paving as described in claim 1, characterized in that, The confirmation of the echo change intensity of each element specifically involves: Based on the first-order difference sequence of the echo positioning sequence, obtain the first-order change sequence of the echo positioning sequence; Using each element of the echo localization sequence as the center, a preset window is established; the mean absolute value of the elements of the first-order change sequence within the window corresponding to each element in the echo localization sequence is positively fused with the variance of all elements within the window corresponding to each element in the echo localization sequence to obtain the echo change intensity of each element in the echo localization sequence.

4. The method for detecting the thickness of ultrasonic paving as described in claim 1, characterized in that, The signal abrupt change trend degree of each element in the echo AIC statistical sequence is obtained as follows: Based on the first-order difference sequence of the echo AIC statistical sequence, the first-order change sequence of the echo AIC statistical sequence is obtained; The result of positively fusing the echo change intensity of each element in the echo localization sequence with the element at the same position in the first-order change sequence of the echo AIC statistical sequence is used as the signal mutation trend degree of each element in the echo AIC statistical sequence.

5. The method for detecting the thickness of ultrasonic paving as described in claim 1, characterized in that, The echo development trend degree of each element in the obtained echo AIC statistical sequence is specifically as follows: The linear fit is performed on each element in the echo AIC statistical sequence and all previous elements to obtain the fitted line for each element. The values ​​of each element and its corresponding fitted line are compared to confirm the regularity of each element. For the echo AIC statistical sequence, the signal mutation trend degree of each element is calculated as the product of the element at the same position in its first-order change sequence. Combined with the negative correlation mapping result of the regular development degree of each element, the echo development trend degree of each element in the echo AIC statistical sequence is obtained.

6. The method for detecting the thickness of ultrasonic paving as described in claim 5, characterized in that, The degree of regularity development is specifically the absolute value of the difference between each element and the value on its corresponding fitted line.

7. The method for detecting the thickness of ultrasonic paving as described in claim 1, characterized in that, The specific echo time is the time corresponding to the element with the greatest echo development trend in the echo AIC statistical sequence.

8. The method for detecting the thickness of ultrasonic paving as described in claim 1, characterized in that, The paving thickness is specifically half the product of the propagation speed of the ultrasonic wave in the paved mixture and the time length corresponding to the first echo moment.

9. A system for detecting the thickness of ultrasonic paving, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method as described in any one of claims 1-8.

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