Evaluation method and system for load transfer capacity of airport pavement joints based on long-range laser vibrometer

Abstract

The present invention relates to a method and system for evaluating the load transfer capacity of airport pavement joints based on long-range laser vibrometer, the method comprising: collecting pavement vibration response data at the wheel track of an aircraft based on long-range laser vibrometer; processing the pavement vibration response data to obtain the dominant mode frequency and damping rate of each test point; taking the pavement damping rate change curve on the left side of the pavement joint and the damping rate change curve on the right side, and the pavement dominant mode frequency change curve on the left side of the pavement joint and the dominant mode frequency change curve on the right side; calculating the damping rate average absolute error P1 and the dominant mode frequency average absolute error P2: finally, evaluating the pavement joint load transfer capacity based on P1 and P2. The present invention evaluates the pavement joint load transfer capacity comprehensively from multiple dimensions by extracting the average absolute error of the dominant mode frequency and damping rate of the pavement panels on both sides of the joint, and by considering the consistency of the vibration laws on the left and right sides of the joint, the coupling strength, and the degree of energy loss in the joint transfer.

Description

Technical Field

[0001] The invention relates to a load transfer evaluation of airport pavement joints, and in particular to a method and system for evaluating the load transfer capacity of airport pavement joints based on long-range laser vibration measurement. Background Art

[0002] The load transfer capacity of the airport pavement joints directly affects the structural bearing capacity and service life. When the load transfer capacity of the airport pavement joints cannot meet the industry standards, the structural bearing capacity of the pavement panel cannot meet the requirements of the aircraft during takeoff and landing, which brings safety hazards and may cause safety accidents in serious cases. At present, the HWD test of the bending and sinking of adjacent panels is mainly used to evaluate the load transfer capacity of the airport pavement joints, but the HWD test for evaluating the load transfer capacity of the pavement joints has shortcomings: the test requires the closure of the runway, which affects the airport operation efficiency; the test mode is single-point and inefficient, and it is difficult to fully and real-time detect the load transfer capacity of the runway joints; the test cannot reflect the ability of the joints to transfer vibration and energy when the aircraft passes through, and it is difficult to fully characterize the load transfer capacity of the joints.

[0003] The invention patent application with publication number CN115825242A discloses an online evaluation method for the load transfer capacity of airport rigid pavement joints, which solves the technical problem of low bending frequency in some HWD testing technologies, resulting in the inability of airport personnel to grasp the joint load transfer capacity in a timely manner, and improves the monitoring frequency to a certain extent. This invention patent requires the accelerometer sensor to be embedded in the pavement in advance, which is not suitable for airport runways where accelerometers are not embedded in the pavement panels at present, and only uses the bending frequency to characterize the joint load transfer capacity, which is not comprehensive enough.

[0004] Therefore, how to evaluate the load transfer capacity of the joints of the airport rigid pavement in a long-term, real-time and accurate manner without affecting the normal operation of the airport runway has become a technical problem that needs to be solved urgently. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies of the above-mentioned prior art and to provide a method and system for evaluating the load transfer capacity of airport pavement joints based on long-range laser vibrometer, which can accurately, comprehensively and in real time evaluate the load transfer capacity of airport rigid pavement joints.

[0006] The technical solution adopted to achieve the purpose of the present invention is a method for evaluating the load transfer capacity of airport pavement joints based on long-range laser vibration measurement, which comprises:

[0007] Collect pavement vibration response data at the aircraft wheel track based on long-range laser vibrometer;

[0008] The pavement vibration response data is processed to obtain the dominant mode frequency FR and damping rate ξ of each test point; the pavement damping rate ξ1 variation curve f on the left side of the pavement joint is taken L The right damping rate ξ2 change curve f R, the change curve of the dominant mode frequency FR1 on the left side of the pavement joint F L The dominant mode frequency FR2 change curve on the right R ;

[0009] The mean absolute error of the damping rate P1 and the mean absolute error of the dominant mode frequency P2 are calculated according to the following formula:

[0010] P1=Σ|fL(x)-fR(x)| / M×100%

[0011] P2=Σ|FL(x)-FR(x)| / M×100%

[0012] Where: M represents the number of measuring points;

[0013] Evaluate the load transfer capacity of pavement joints based on P1 and P2.

[0014] Furthermore, the load transfer capacity of the joint is evaluated jointly by P1 and P2, and different levels of load transfer capacity are evaluated for P1 and P2 in different numerical ranges. When P1 is compared with P2, the load transfer capacity level of the one with a lower level of load transfer capacity is taken as the final load transfer capacity evaluation result.

[0015] In the above technical scheme, the pavement vibration response data at the aircraft wheel track is collected, and the FFT Fourier transform is performed on the pavement vibration corresponding data to obtain the frequency domain response function. A filter is used to obtain the 0-100 Hz frequency band response, and the frequency corresponding to the main peak is locked as the dominant mode frequency. The modal shape function and the damping rate ξ are solved by damping polynomial fitting, and the dominant mode frequency FR and the damping rate ξ of each test point are extracted.

[0016] In the above technical solution, collecting the pavement vibration response data at the aircraft wheel track includes:

[0017] The adjacent pavement panels on both sides of the joint are tested, and each pavement is divided into multiple 1m×1m sub-areas for testing. Test points are randomly selected in each sub-area, and the test points must fall on the aircraft wheel track;

[0018] The long-range laser vibrometer is fixed on both sides of the runway, and the laser is aimed at the test point to record the changes in the displacement signal of the test point in the three directions of X, Y, and Z;

[0019] The main landing gear of a single aircraft driving in and out of the target board is considered an event. The target board and the next board that the aircraft is about to drive into in a single aircraft event are tested.

[0020] In the above technical solution, a laser wheel track meter is used to obtain the position of the aircraft, and the aircraft wheel track is analyzed by combining opposite layout with lateral layout.

[0021] In addition, the present invention also provides an airport pavement joint load transfer capacity evaluation system based on long-range laser vibration measurement, the system comprising:

[0022] Data acquisition module: Through the airport pavement multi-source information perception system based on long-range laser vibration measurement, the vibration response data of the aircraft model, wheel track, lateral offset, and adjacent pavement panel measurement points on both sides of the joint are obtained;

[0023] A data processing module is used to obtain the damping rate and dominant vibration frequency of each measuring point on the pavement, and further obtain the damping rate change curve and dominant vibration frequency change curve of the adjacent pavement panels on both sides of the joint;

[0024] The data application module calculates the mean absolute error of the damping rate and the mean absolute error of the dominant mode frequency of the adjacent pavement panels on both sides of the joint.

[0025] In the above technical solution, the airport pavement multi-source information perception system based on long-distance laser vibrometer includes a laser wheel track meter, a distributed laser vibrometer and a perception data transmission network.

[0026] The present invention has the following advantages:

[0027] 1. The present invention adopts a long-range laser vibrometer, which can synchronously collect vibration response data of various areas of the pavement on both sides of the joint under the event of an aircraft passing through, realize real-time and high-precision detection of the load transfer capacity of the joint, and is more conducive to the detailed evaluation of the load transfer capacity of the joint.

[0028] 2. By extracting the average absolute error of the dominant mode frequency and damping rate of the pavement panels on both sides of the joint, and considering the consistency of the vibration laws on the left and right sides of the joint, the coupling strength, and the degree of energy loss in the joint, the load transfer capacity of the pavement joint is comprehensively evaluated from multiple dimensions.

[0029] 3. The invention has strong anti-interference ability, relatively stable detection results, no need for on-site operation, and reduces the detection cost of airport pavement. It does not need to occupy the runway during detection, and will not affect the normal operation of the runway. It has a long detection cycle and a wide coverage area. It can achieve non-destructive, comprehensive, real-time, and high-precision measurement of the load transfer capacity of the joints of the rigid pavement of the airport. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the structure of the airport pavement joint load transfer capacity evaluation system based on long-distance laser vibration measurement of the present invention.

[0031] Figure 2 The present invention is a flow chart of the method for evaluating the load transfer capacity of airport pavement joints based on long-range laser vibrometer. DETAILED DESCRIPTION

[0032] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0033] like Figure 1 As shown, the present invention provides an airport pavement joint load transfer capacity evaluation system based on long-range laser vibration measurement, comprising:

[0034] Data acquisition module: Through the airport pavement multi-source information perception system based on long-distance laser vibrometer, the vibration response data of the aircraft model, wheel track, lateral offset, and adjacent pavement panel measurement points on both sides of the joint are obtained. The hardware facilities corresponding to this part of the module are the airport pavement multi-source information perception system based on long-distance laser vibrometer, which specifically includes a laser wheel track meter 1, a distributed laser vibrometer 2, and a perception data transmission network 3.

[0035] The data processing module 7 is used to obtain the damping rate and dominant vibration frequency of each measuring point on the pavement, and further obtain the damping rate change curve and dominant vibration frequency change curve of the adjacent pavement panels on both sides of the joint. The data processing module is used to extract the dominant mode frequency FR and damping rate ξ of each test point based on the FFT Fourier transform of the original vibration response data and the damping polynomial fitting to solve the modal shape function and damping rate ξ. This embodiment is implemented by computer and related software. For example, the calculation formula is set in the software, and the dominant mode frequency FR and damping rate ξ of each test point can be calculated after the corresponding data is input.

[0036] The data application module calculates the average absolute error of the damping rate and the average absolute error of the dominant mode frequency of the adjacent road panels on both sides of the joint. This embodiment uses a computer and related calculation software to calculate and implement.

[0037] like Figure 2 As shown, the process of evaluating the load transfer capacity of airport pavement joints through the above evaluation system includes:

[0038] S1. Collect pavement vibration response data at the aircraft wheel track.

[0039] This embodiment collects information through a multi-source airport pavement perception system based on long-range laser vibrometer. The system includes multiple laser wheel track meters and long-range laser vibrometers. The laser wheel track meter 1 is used to obtain the position of the aircraft 6. The aircraft model, aircraft wheel track, aircraft lateral offset, and aircraft taxiing speed are analyzed by combining opposite layout with lateral layout. The laser vibrometers 2 are arranged in a distributed manner, and the vibration response information of each point on the pavement is measured by using the laser geometry principle and the Doppler effect. The laser vibrometer collects the pavement vibration signal at the aircraft wheel track and transmits it to the data terminal through the perception data transmission network 3, thereby realizing real-time monitoring of the pavement structure vibration under the aircraft passing event.

[0040] The specific collection process is as follows: the adjacent pavement panels on both sides of the joint 5 are tested, each pavement is divided into multiple 1m×1m sub-areas for testing, 2 to 3 test points are randomly selected in each sub-area, and the test points must fall on the aircraft wheel tracks to ensure the randomness and representativeness of the data.

[0041] The long-range laser vibrometer is fixed on both sides of the airport runway 4, and the laser is aimed at the test point to record the changes in the displacement signal of the test point in the three directions of X, Y, and Z.

[0042] The main landing gear of a single aircraft driving into or out of the target board is defined as an event, and the target board and the next board that the aircraft is about to drive into in the single aircraft event are tested.

[0043] The above-mentioned sensing system is used to record the vibration response data of different aircraft in real time. The data contains the frequency domain characteristics and time domain characteristics of each point on the pavement, providing a basis for subsequent data processing and joint evaluation.

[0044] S2. Calculate the dominant mode frequency FR and damping rate ξ of each test point based on the pavement vibration response data, including:

[0045] Perform FFT Fourier transform on the original vibration response data to obtain the frequency domain response function, use a filter to obtain the 0-100HZ frequency band response, lock the frequency corresponding to the main peak as the dominant mode frequency, use damping polynomial fitting to solve the modal shape function and damping rate ξ, and extract the dominant mode frequency FR and damping rate ξ of each test point. For example, set the calculation formula in the software of the data processing module, and after entering the corresponding data, the dominant mode frequency FR and damping rate ξ of each test point can be calculated.

[0046] The variation law of damping rate and dominant mode frequency of adjacent pavement panels on both sides of the joint is extracted, and polynomial function fitting is used to obtain the ξ1 variation curve f of the pavement on the left side of the joint. L The right side ξ2 variation curve f R , the change curve of the dominant mode frequency FR1 on the left side of the pavement joint F L The dominant mode frequency FR2 change curve on the right R .

[0047] S3. Calculate the mean absolute error P1 of the damping rate and the mean absolute error P2 of the dominant mode frequency.

[0048] In this embodiment, the damping rate and the dominant mode frequency fitting curve of the adjacent road panels on both sides of the joint are calculated by the data application module, and the damping rate mean absolute error P1 and the dominant mode frequency mean absolute error P2. The data processing module can be used to set a calculation formula in the calculation software, and P1 and P2 can be calculated after inputting the corresponding data.

[0049] P1 and P2 are calculated by the following formula:

[0050] P1=Σ|fL(x)-fR(x)| / M×100%

[0051] P2=Σ|FL(x)-FR(x)| / M×100%

[0052] Where: M represents the number of measuring points.

[0053] S4. Evaluate the load transfer capacity of airport pavement joints based on P1 and P2

[0054] Since the damping rate characterizes the degree of energy dissipation after a single vibration of the structure, the damping rates on both sides of the joint are consistent, indicating that the energy can be fully transferred and dissipated at the joint. The dominant mode frequency characterizes the stiffness properties of the structure. When the dominant frequencies on both sides of the joint are consistent, it means that both sides of the joint can produce a consistent response in terms of constraint stiffness rather than a local response, which is more conducive to the transfer of load at the joint. P1 quantitatively characterizes the consistency and coupling strength of the vibration law on the left and right sides of the joint, and P2 quantitatively characterizes the consistency of the energy loss law on the left and right sides of the joint, and the degree of energy loss at the joint. Therefore, the present invention evaluates the load transfer capacity of the joint through P1 and P2.

[0055] This embodiment uses a grade standard to evaluate the load transfer capacity of the joint, as shown in Table 1 below:

[0056] grade <![CDATA[P1]]> <![CDATA[P2]]> A <![CDATA[P1≤5%]]> <![CDATA[P2≤5%]]> B <![CDATA[5%≤P1≤10%]]> <![CDATA[5%≤P2≤10%]]> C <![CDATA[10%≤P1]]> <![CDATA[10%≤P2]]>

[0057] Table 1

[0058] Of P1 and P2, the lower level is used as the evaluation level of joint load transfer. For example, if P1 is A and P2 is B, the joint load transfer capacity is B. The following Table 2 shows the evaluation results of joint load transfer capacity based on P1 and P2:

[0059] grade Evaluation results A The joints have strong load transfer capacity and can serve normally. B The load transfer capacity of the joints is average and requires regular or real-time monitoring. C The joints have poor load transfer capacity and need to be repaired in time.

[0060] Table 2

Claims

1. A method for evaluating the load transfer capacity of airport pavement joints based on long-range laser vibration measurement, characterized in that: include: Collect pavement vibration response data at the aircraft wheel track based on long-range laser vibrometer; The pavement vibration response data is processed to obtain the dominant mode frequency FR and damping rate ξ of each test point; the pavement damping rate ξ1 variation curve f on the left side of the pavement joint is taken L The right damping rate ξ2 change curve f R , the change curve of the dominant mode frequency FR1 on the left side of the pavement joint F L The dominant mode frequency FR2 change curve on the right R ; The mean absolute error of the damping rate P1 and the mean absolute error of the dominant mode frequency P2 are calculated according to the following formula: P1=Σ|fL(x)-fR(x)| / M×100% P2=Σ|FL(x)-FR(x)| / M×100% Where: M represents the number of measuring points; The load transfer capacity of the joint is evaluated by P1 and P2. Different levels of load transfer capacity are evaluated for P1 and P2 in different numerical ranges. When P1 is compared with P2, the load transfer capacity level of the one with a lower level of load transfer capacity is taken as the final load transfer capacity evaluation result.

2. The method for evaluating the load transfer capacity of airport pavement joints based on long-range laser vibration measurement according to claim 1 is characterized in that: The pavement vibration response data at the aircraft wheel track are collected, and the pavement vibration response data are subjected to FFT Fourier transform to obtain the frequency domain response function. A filter is used to obtain the 0-100 Hz frequency band response, and the frequency corresponding to the main peak is locked as the dominant mode frequency. The modal shape function and the damping rate ξ are solved by damping polynomial fitting, and the dominant mode frequency FR and the damping rate ξ of each test point are extracted.

3. The method for evaluating the load transfer capacity of airport pavement joints based on long-range laser vibration measurement according to any one of claims 1-2, characterized in that: The collection of pavement vibration response data at the aircraft wheel path includes: The adjacent pavement panels on both sides of the joint are tested, and each pavement is divided into multiple 1m×1m sub-areas for testing. Test points are randomly selected in each sub-area, and the test points must fall on the aircraft wheel track; The long-range laser vibrometer is fixed on both sides of the runway, and the laser is aimed at the test point to record the changes in the displacement signal of the test point in the three directions of X, Y, and Z; The main landing gear of a single aircraft driving in and out of the target board is considered an event. The target board and the next board that the aircraft is about to drive into in a single aircraft event are tested.

4. The method for evaluating the load transfer capacity of airport pavement joints based on long-range laser vibration measurement according to claim 3 is characterized by: This includes using a laser wheel track meter to obtain the aircraft's position, and analyzing the aircraft's wheel tracks through opposite and lateral deployment.

5. A system for evaluating the load transfer capacity of airport pavement joints based on long-range laser vibration measurement, characterized in that: include: Data acquisition module: Through the airport pavement multi-source information perception system based on long-range laser vibration measurement, the vibration response data of the aircraft model, wheel track, lateral offset, and adjacent pavement panel measurement points on both sides of the joint are obtained; A data processing module is used to obtain the damping rate and dominant vibration frequency of each measuring point on the pavement, and further obtain the damping rate change curve and dominant vibration frequency change curve of the adjacent pavement panels on both sides of the joint; The data application module calculates the mean absolute error of damping rate and the mean absolute error of dominant mode frequency of adjacent pavement panels on both sides of the joint; The pavement joint load transfer capacity evaluation module is used to jointly evaluate the joint load transfer capacity through P1 and P2, and evaluate different levels of load transfer capacity when P1 and P2 are in different numerical ranges. When P1 is compared with P2, the load transfer capacity level of the one with a lower level of load transfer capacity is taken as the final load transfer capacity evaluation result.

6. The airport pavement joint load transfer capacity evaluation system based on long-range laser vibration measurement according to claim 5 is characterized by: The airport pavement multi-source information perception system based on long-distance laser vibrometer includes a laser wheel track meter, a distributed laser vibrometer and a perception data transmission network.

Images