Nondestructive testing method, device, equipment, system and medium for existing building cover plate

Abstract

The invention relates to the technical field of building engineering, in particular to a nondestructive testing method, device, equipment, system and medium for an existing building cover plate, and aims to quickly and reliably detect the actual rigidity of the existing cover plate structure by obtaining the actual measurement modal information of the cover plate from the modal test of the cover plate structure. The modal test parameters of the cover plate can be directly associated with the structural rigidity of the upper cover plate of the operation library of the metro depot during use, so that the functions of non-destructive testing and non-destructive safety evaluation on the existing building cover plate can be realized during use; the modal test parameters of the cover plate can be directly associated with the structural rigidity of the upper cover plate of the operation library of the metro depot; the technical problem of accurately detecting and evaluating the existing cover plate structure in the development and construction process of the subway depot upper cover is solved; in the process of modal test data acquisition, the influence of the safety of the acceleration sensor and installation and fixation on the accuracy of detection data is considered, so that the safety evaluation of the rigidity of the existing cover plate structure is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of construction engineering, and particularly relates to a method, device, equipment, system and medium for non-destructive testing of existing building cover plates. Background Technique

[0002] With the rapid development of urban rail transit in China, the number of vehicle depots for rail transit (such as subways) in each city is increasing, and the existence of vehicle depots will cause a reduction in urban development land. Therefore, it is particularly important to carry out secondary development on vehicle depots.

[0003] During the construction of the upper cover development of the subway vehicle depot, the cover plate structure of the operation depot will bear many construction loads, which may have an adverse impact on the lower cover plate structure and the safety of subway operation. How to correctly evaluate the bearing capacity of the cover plate structure during the construction process is of great significance. The stiffness of the cover plate structure is not only an important index for structural design and construction quality inspection, but also an important parameter for evaluating the bearing capacity of the structure. For the cover plate structure, it is relatively difficult to detect the damaged parts in time by manual inspection, and it is also very difficult to conduct actual stiffness testing on it by using pseudo-static loading. At present, the research on the stiffness testing of vehicle depot structures is relatively less, and the determination of bridge structure states is relatively more, mainly based on modal experiments, and the safety state of the structure is qualitatively evaluated by using natural vibration frequencies and vibration mode response indexes. However, the basic modal test parameters cannot be directly related to the structural stiffness of the upper cover plate of the operation depot of the subway vehicle depot. Summary of the Invention

[0004] The main purpose of this application is to provide a method, device, equipment, system and medium for non-destructive testing of existing building cover plates, aiming to solve the technical problem that the basic modal test parameters in the related art cannot be directly related to the structural stiffness of the upper cover plate of the operation depot of the subway vehicle depot.

[0005] To achieve the above purpose, this application proposes a method for non-destructive testing of existing building cover plates, including the following steps:

[0006] Install an acceleration detection device on each of a plurality of preset measurement points distributed at intervals in a preset detection area;

[0007] Fix and protect the acceleration sensor by using a sensor installation and fixation protection device. The acceleration sensor protection device mainly includes a protection device fixing plate, a sensor fixing plate and a sensor protection device, which has the function of simple and rapid installation and removal, and is more conducive to improving the accuracy of acceleration sensor data acquisition;

[0008] Obtain the standardized vibration mode matrix of the cover plate structure according to the measured data collected by all the acceleration detection devices;

[0009] Obtaining the measured modal stiffness of the cover plate according to the standardized vibration mode matrix;

[0010] According to the measured modal stiffness and the theoretical design stiffness, the dimensionless coefficient of the stiffness difference of the cover plate is obtained using Formula 1, and the non-destructive testing result of the cover plate is obtained; wherein, Formula 1 is:

[0011]

[0012] λ is the dimensionless coefficient of the stiffness difference, K1 is the measured modal stiffness, and K2 is the theoretical design stiffness.

[0013] In one embodiment, the step of obtaining a normalized mode shape matrix of the cover structure based on measured data collected by all the acceleration detection devices includes:

[0014] Based on the measured data collected by all the acceleration detection devices, the normalization coefficient of the cover plate is calculated using Formula 2; wherein, Formula 2 is:

[0015]

[0016] γ i is the standardized coefficient, M a is the mass matrix of the cover plate, is the column vector of the i-th order measured mode shape of the cover plate, For the The transposed vector of

[0017] According to the normalization coefficient, the standard vibration mode of the cover plate is calculated using Formula 3; wherein, Formula 3 is:

[0018]

[0019] is the column vector of the i-th order normalized vibration mode matrix, is the column vector of the i-th order measured mode shape of the cover plate, γ i is the standardization coefficient.

[0020] In one embodiment, the step of obtaining the measured modal stiffness of the cover plate according to the normalized mode shape matrix includes:

[0021] According to the normalized mode shape matrix, combined with the predicted modal displacement matrix of the cover plate and the inferred design vertical load of the cover plate, the measured modal stiffness of the cover plate is calculated using Formula 5; wherein, Formula 5 is:

[0022]

[0023] Let \(K1\) be the measured modal stiffness, \(F\) be the designed vertical load, and \(\varepsilon\) be the designed modal displacement.

[0024] In one embodiment, the step of calculating the measured modal stiffness of the cover plate by using Formula Five according to the standardized mode shape matrix, in combination with the predicted modal displacement matrix of the cover plate and the deduced designed vertical load of the cover plate includes:

[0025] According to the standardized mode shape matrix, calculate the measured displacement amplitude matrix of the cover plate by using Formula Six; wherein, Formula Six is:

[0026]

[0027] \(\varphi\) is the standardized mode shape matrix, \(\varphi^{\mathrm{T}}\) T is the transpose matrix of \(\varphi\), \(\omega_i\) i is the \(i\)-th order modal frequency;

[0028] Deduce the vertical load of the cover plate according to the preset bending moment of the cover plate;

[0029] According to the measured displacement flexibility matrix and the vertical load, calculate and predict the modal displacement matrix by using Formula Seven; wherein, Formula Seven is:

[0030] \(S = DF\),

[0031] where \(S\) is the modal displacement matrix, \(D\) is the measured displacement flexibility matrix, and \(F\) is the designed vertical load;

[0032] In combination with the modal displacement matrix and the designed vertical load, calculate the measured modal stiffness of the cover plate by using Formula Five.

[0033] In one embodiment, after calculating the measured modal stiffness of the cover plate by using Formula Five in combination with the modal displacement matrix and the designed vertical load, it further includes:

[0034] Calculate the designed displacement of the cover plate under the vertical load, and in combination with the vertical load, calculate the theoretical designed stiffness of the cover plate by using Formula Eight; wherein, Formula Eight is:

[0035]

[0036] where \(K2\) is the theoretical designed stiffness of the cover plate, \(D\) is the measured displacement flexibility matrix, \(F\) is the designed vertical load, and \(S\) is the modal displacement matrix.

[0037] In one embodiment, before the step of respectively installing an acceleration detection device on a plurality of preset measurement points distributed at intervals in the preset detection area, the method further includes:

[0038] Setting the preset detection area on the cover plate according to the actual service state of the cover plate and the actual construction conditions in the area where the cover plate is located;

[0039] Calculating the theoretical vibration mode of the cover plate according to the preset completion data of the cover plate;

[0040] Setting a plurality of preset measurement points distributed at intervals in the preset detection area according to the theoretical vibration mode and the key cross-sections of the cover plate; wherein, the key cross-sections are the mid-span cross-section of the cover plate and / or the cross-section where the plate thickness changes and / or the beam-plate connection cross-section.

[0041] Based on the same technical concept, in a second aspect, the present invention further provides a non-destructive detection device for an existing building cover plate, including:

[0042] An equipment installation module, configured to respectively install an acceleration detection device on a plurality of preset measurement points distributed at intervals in the preset detection area;

[0043] A standardized vibration mode matrix acquisition module, configured to acquire the standardized vibration mode matrix of the cover plate structure according to the measured data collected by all the acceleration detection devices;

[0044] A measured modal stiffness acquisition module, configured to acquire the measured modal stiffness of the cover plate according to the standardized vibration mode matrix;

[0045] A result output module, configured to obtain the non-dimensional coefficient of the stiffness difference of the cover plate according to the measured modal stiffness and the theoretical design stiffness by using Formula 1, and obtain the non-destructive detection result of the cover plate.

[0046] Based on the same technical concept, in a third aspect, the present invention further provides a non-destructive detection equipment for an existing building cover plate. The non-destructive detection equipment for an existing building cover plate includes a processor and a memory. An existing building cover plate non-destructive detection program is stored on the memory. When the existing building cover plate non-destructive detection program is executed by the processor, the non-destructive detection method for an existing building cover plate described in the first aspect is implemented.

[0047] Based on the same technical concept, in a fourth aspect, the present invention further provides a non-destructive detection system for an existing building cover plate, including:

[0048] The non-destructive detection equipment for an existing building cover plate described in the third aspect; and,

[0049] A data acquisition device, which is installed in the blasting operation area of the tunnel, and the existing building cover plate non-destructive testing device is communicatively connected with the data acquisition device and transmits the acquired data information to the existing building cover plate non-destructive testing device.

[0050] Based on the same technical concept, in a fifth aspect, the present invention further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by one or more processors, the existing building cover plate non-destructive testing method described in the first aspect is implemented.

[0051] One or more technical solutions proposed in this application have at least the following technical effects:

[0052] When the technical solution of this application is used, an acceleration detection device is respectively installed on a plurality of preset measurement points distributed at intervals in the preset detection area of the cover plate structure of the subway operation depot. According to the measured modal data of the cover plate structure collected by all acceleration detection devices, a standardized vibration mode matrix of the cover plate structure is obtained. According to the standardized vibration mode matrix, the measured modal stiffness of the cover plate is obtained. According to the measured modal stiffness and the theoretical design stiffness of the cover plate structure, the dimensionless coefficient of the stiffness difference of the cover plate structure is obtained by using a formula, and the non-destructive testing result of the cover plate is obtained.

[0053] On the one hand, the method of the present invention quickly and reliably detects the actual stiffness of the existing cover plate structure by obtaining the measured modal information of the cover plate from the modal test of the cover plate structure, so that when the present invention is used, the modal test parameters of the cover plate can be directly correlated with the structural stiffness of the upper cover plate of the operation depot of the subway vehicle depot. Furthermore, when the present invention is used, the functions of non-destructive testing and non-destructive safety assessment of the existing building cover plate can be realized, and the technical problem of accurately detecting and evaluating the existing cover plate structure during the construction of the upper cover development of the subway vehicle depot is solved. On the other hand, the present invention considers the safety of the acceleration sensor and the influence of the installation and fixation on the accuracy of the detection data during the process of modal test data acquisition, and then affects the evaluation of the structural stiffness. A sensor installation protection device is designed, which is more suitable for the stiffness detection of the existing cover plate structure during the upper cover development of the subway vehicle depot, and the calculated detection result is more accurate, so as to realize the safety assessment of the stiffness of the existing cover plate structure. Description of the Drawings

[0054] The accompanying drawings here are incorporated into the specification and form a part of this specification, showing embodiments consistent with this application, and are used together with the specification to explain the principles of this application.

[0055] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required in the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0056] Figure 1 It is a schematic flowchart of the non-destructive testing method for the existing building cover plate of the present application;

[0057] Figure 2 It is a schematic flowchart of step S200 of the example of the present application;

[0058] Figure 3 It is a schematic flowchart of step S310 of the example of the present application;

[0059] Figure 4 It is a schematic flowchart of some embodiments of the example of the present application;

[0060] Figure 5 It is a schematic structural diagram of the non-destructive testing equipment for the existing building cover plate of the example of the present application.

[0061] The realization of the purpose, functional features and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. Specific Embodiments

[0062] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application and are not used to limit the present application.

[0063] To better understand the technical solutions of the present application, the following will be described in detail in combination with the drawings in the specification and the specific embodiments.

[0064] Please refer to Figures 1 to 5 , the present application proposes a non-destructive testing method for the existing building cover plate in the first embodiment, including the following steps:

[0065] S100. Install an acceleration detection device on each of a plurality of preset measurement points distributed at intervals in a preset detection area;

[0066] In this embodiment, the exemplary acceleration detection device can be, but is not limited to, an acceleration sensor that has been put into use in the prior art. After the acceleration sensor is installed at the preset measurement point, an acceleration sensor protection device is used to protect each sensor during the detection process to avoid damage to the acceleration sensor during the acquisition process.

[0067] It should be clearly stated that in the sensor protection device exemplified in this embodiment, it includes a cover plate and a protection cylinder surrounding the outer periphery of the cover plate. One end of the exemplified protection cylinder is connected to the cover plate, and the other end is connected to the corresponding preset measurement point, and then corresponding measurements can be carried out according to each preset measurement point.

[0068] It needs to be further clarified that in this embodiment, both the cover plate and the protection cylinder in the exemplified sensor protection device should be made of lightweight and high-strength alloy materials. At the same time, a plurality of bolt holes should be provided on the protection cylinder to fix it to the preset measurement point.

[0069] S200. According to the measured data collected by all the acceleration detection devices, obtain the standardized mode shape matrix of the cover plate structure;

[0070] In this embodiment, the measured frequency, mode shape and other data exemplified can be but are not limited to being obtained by immediate measurement; the standardized mode shape matrix exemplified in this embodiment is obtained after standardizing the mode shape matrix relative to the mass matrix;

[0071] In this embodiment, the specific process of obtaining the standardized mode shape matrix is as follows:

[0072] S210. According to the measured data collected by all the acceleration detection devices, use formula two to calculate the standardized coefficient of the cover plate; where, formula two is:

[0073]

[0074] γ i is the standardized coefficient, M a is the mass matrix of the cover plate, and the mass matrix is obtained from experimental measurement, is the i-th order measured modal mode shape column vector of the cover plate, is the transpose vector;

[0075] Among them, the obtaining process of formula two is to combine formula and formula φ i T Mφ i = 1, (i = 1, 2, 3...) and solve simultaneously to obtain formula two.

[0076] S220. According to the standardized coefficient, use formula three to calculate the standard mode shape of the cover plate; where, formula three is:

[0077]

[0078] is the i-th order standardized mode shape matrix column vector, is the i-th order measured modal vibration mode column vector of the cover plate, γ i is the normalization coefficient.

[0079] S300. Obtain the measured modal stiffness of the cover plate according to the normalized vibration mode matrix;

[0080] In this embodiment, the exemplary measured modal stiffness refers to the structural stiffness obtained by the modal test method, which is called the measured modal stiffness;

[0081] In this embodiment, the specific process of obtaining the measured modal stiffness is as follows:

[0082] S311. Calculate and obtain the measured displacement flexibility matrix of the cover plate according to the normalized vibration mode matrix by using Formula 6; where, Formula 6 is:

[0083]

[0084] φ is the normalized vibration mode matrix, φ T is the transpose matrix of φ, ω i is the i-th order modal frequency;

[0085] S312. Deduce the vertical load of the cover plate according to the preset bending moment of the cover plate;

[0086] S313. Calculate and predict the modal displacement matrix according to the measured displacement flexibility matrix and the vertical load by using Formula 7; where, Formula 7 is:

[0087] S = DF,

[0088] S is the modal displacement matrix, that is, the matrix composed of the displacement values generated by the structure under the load in the modal test is called the modal displacement matrix, D is the measured displacement flexibility matrix, flexibility represents the deformation value generated by the structure under the action of unit load, that is, the matrix composed of the deformation values obtained in the modal test is called the displacement flexibility matrix, and F is the designed vertical load;

[0089] Specifically, the exemplary designed vertical load can be calculated by using the formula where, F is the designed bending moment of the cover plate, M b is the designed bending moment of the cover plate, and h is the designed thickness of the cover plate.

[0090] S314. Combine the modal displacement matrix and the designed vertical load, and calculate and obtain the measured modal stiffness of the cover plate by using Formula 5; Formula 5 is:

[0091]

[0092] K1 is the measured modal stiffness. As the most important mechanical property of the structure, stiffness is the inherent mechanical essence of the displacement and deformation of the structure under the action of load. The stiffness of the structure obtained by the modal test method is the modal stiffness. F is the designed vertical load, and ε is the modal displacement of the key section of the cover plate structure under the designed vertical load.

[0093] S400. According to the measured modal stiffness and the theoretical design stiffness, use Formula 1 to obtain the dimensionless coefficient of the stiffness difference of the cover plate, and obtain the non-destructive testing result of the cover plate; wherein, Formula 1 is:

[0094]

[0095] λ is the dimensionless coefficient of the stiffness difference, K1 is the measured modal stiffness, and K2 is the theoretical design stiffness.

[0096] It should be specifically and clearly stated that in this embodiment, the essence of the dimensionless coefficient of the stiffness difference exemplified is to conduct a comparative analysis of the measured stiffness K1 and the theoretical design stiffness K2. That is, first take the difference between K1 and K2. In order to eliminate the influence of the dimension, take the ratio of the stiffness difference between K1 and K2 to K2 to obtain the dimensionless coefficient of the stiffness difference λ, so as to achieve the purpose of evaluating the actual stiffness of the cover plate.

[0097] In this embodiment, by installing an acceleration detection device on the preset measurement points distributed at multiple intervals in the preset detection area respectively, according to the measured data collected by all acceleration detection devices, obtain the standardized mode shape matrix of the cover plate structure, according to the standardized mode shape matrix, obtain the measured modal stiffness of the cover plate, according to the measured modal stiffness and the theoretical design stiffness, use the formula to obtain the dimensionless coefficient of the stiffness difference of the cover plate, and obtain the non-destructive testing result of the cover plate, so that when the present invention is used, it can directly associate the modal test parameters of the substrate with the structural stiffness of the upper cover plate of the subway depot operation depot, and further enable the present invention to realize the functions of non-destructive testing and non-destructive safety assessment of the existing building cover plate when in use.

[0098] On the one hand, the method of the present invention obtains the measured modal information of the cover plate from the modal test of the cover plate structure, quickly and reliably detects the actual stiffness of the existing cover plate structure, enables the modal test parameters of the cover plate to be directly related to the structural stiffness of the upper cover plate of the subway depot during the use of the present invention, and further enables the present invention to realize the functions of non-destructive detection and non-destructive safety evaluation of the existing building cover plate during use, solving the technical problem of accurately detecting and evaluating the existing cover plate structure during the construction of the upper cover development of the subway depot; on the other hand, the present invention considers the safety of the acceleration sensor and the influence of the installation and fixation on the accuracy of the detection data during the process of collecting data by modal test, and further affects the evaluation of the structural stiffness. A sensor installation protection device is designed, which is more suitable for the stiffness detection of the existing cover plate structure during the development of the upper cover of the subway depot, and the calculation result of the detection is more accurate, so as to realize the safety evaluation of the stiffness of the existing cover plate structure.

[0099] In one embodiment, step S200 includes:

[0100] S210. According to the measured data collected by all the acceleration detection devices, calculate the normalization coefficient of the cover plate by using Formula 2; wherein, Formula 2 is:

[0101]

[0102] γ i is the normalization coefficient, M a is the mass matrix of the cover plate, is the i-th order measured modal vibration mode column vector of the cover plate, is the transpose vector;

[0103] S220. According to the normalization coefficient, calculate the standard vibration mode of the cover plate by using Formula 3; wherein, Formula 3 is:

[0104]

[0105] is the i-th order normalized vibration mode matrix column vector, is the i-th order measured modal vibration mode column vector of the cover plate, γ i [[ID=3,6]]is the normalization coefficient.

[0106] In one embodiment, step S300 includes:

[0107] S310. According to the normalized vibration mode matrix, combined with the predicted modal displacement matrix of the cover plate and the deduced designed vertical load of the cover plate, calculate and obtain the measured modal stiffness of the cover plate by using Formula 5; wherein, Formula 5 is:

[0108]

[0109] K1 is the measured modal stiffness, F is the designed vertical load, and ε is the modal displacement matrix.

[0110] In one embodiment, step S310 includes:

[0111] S311. Obtain the measured displacement amplitude matrix of the cover plate by using Formula 6 according to the standardized mode shape matrix; wherein, Formula 6 is:

[0112]

[0113] φ is the standardized mode shape matrix, φ T is the transpose matrix of φ, ω i is the i-th order modal frequency;

[0114] S312. Deduce the vertical load of the cover plate according to the preset bending moment of the cover plate;

[0115] S313. Calculate and predict the modal displacement matrix by using Formula 7 according to the measured displacement flexibility matrix and the vertical load; wherein, Formula 7 is:

[0116] S = DF,

[0117] S is the modal displacement matrix, D is the measured displacement flexibility matrix, and F is the designed vertical load;

[0118] S314. Calculate the measured modal stiffness of the cover plate by using Formula 5 in combination with the modal displacement matrix and the designed vertical load.

[0119] In one embodiment, after step S314, it further includes:

[0120] S315. Calculate the designed displacement of the cover plate under the action of the vertical load, and calculate the theoretical design stiffness of the cover plate by using Formula 8 in combination with the vertical load; wherein, Formula 8 is:

[0121]

[0122] K2 is the theoretical design stiffness of the cover plate, D is the measured displacement flexibility matrix, F is the designed vertical load, and S is the modal displacement matrix.

[0123] In one embodiment, before the step of respectively installing an acceleration detection device at a plurality of preset measurement points distributed at intervals in the preset detection area, it further includes:

[0124] S500. Set the preset detection area on the cover plate according to the actual service status of the cover plate and the actual construction conditions in the area where the cover plate is located;

[0125] S600. Calculate the theoretical vibration mode of the cover plate according to the preset completion data of the cover plate;

[0126] S700. Set a plurality of preset measuring points distributed at intervals in the preset detection area according to the theoretical vibration mode and the key cross-sections of the cover plate; wherein, the key cross-sections are the mid-span cross-section of the cover plate and / or the cross-section where the plate thickness changes and / or the beam-plate connection cross-section.

[0127] More specifically, the present invention will be specifically described below by taking the cover plate structure model of the laboratory as an example.

[0128] In this embodiment, in the cover plate structure model of the laboratory, the beam and slab adopt C30 concrete, the column adopts C60 concrete, the storey height is 3.3m, the plate thickness is 0.15m, the size of a single plate is 8.0 * 12.4m, it is a two-way plate, a single plate is divided into six areas by the main and secondary beams, the vertical beam cross-section size of the main beam is 0.7 * 1.3m, the horizontal beam cross-section size is 0.5 * 1.0m, the secondary beam cross-section size is 0.4 * 0.8m, and the column cross-section size is 2.0 * 1.4m. Quasi-static tests and ambient excitation modal tests are carried out respectively, and the modal stiffness measured in the modal test is compared and analyzed with the structural stiffness measured in the quasi-static test to prove the accuracy of the measured modal stiffness. Then, based on the finite element model of the cover plate structure, the theoretical design stiffness of the cover plate structure is calculated. Finally, the dimensionless coefficient of the stiffness difference between the measured modal stiffness and the theoretical design stiffness is calculated to evaluate and judge the stiffness condition of the model cover plate structure.

[0129] Collect the basic data of the model cover plate structure and understand the engineering overview of the cover plate structure of the operation library.

[0130] Establish a finite element model according to the relevant data of the model cover plate structure, determine the positions of the measuring points, and complete the installation of acceleration sensors at the corresponding measuring points in combination with the acceleration sensor protection device.

[0131] After installing the acceleration sensors, collect the vertical acceleration time-history response data of the cover plate structure under ambient excitation, and use modal parameter identification methods such as EFDD, polymax, and SSI to identify that the first two natural frequencies of the cover plate structure are 13.665HZ and 15.723HZ respectively, and identify the first two modal vibration modes of the cover plate structure.

[0132] The present invention can not only identify and extract the stiffness information of the actual structure of the cover plate structure from the modal test data of the cover plate structure, simply and reliably detect the actual stiffness of the cover plate structure, but also has the characteristics of being fast and convenient in practical engineering applications and having a high reliability of evaluation results, which can save manpower and financial resources and has remarkable economic benefits.

[0133] The present invention designs a special protection device for the acceleration sensor. During the experiment, this device can protect the sensor and reduce the possibility of data distortion caused by sensor damage, greatly improving the reliability of the detection data.

[0134] Calculate the modal normalization coefficient. Using the identified frequencies and modes, calculate the modal normalization coefficient. The first two-order modal normalization coefficients are 1.987×10 -3 and 2.286×10 -3 , and its numerical value is related to the amplitude of the measured mode and the strength of the ambient excitation, etc.

[0135] Calculate the normalized mode matrix of the cover plate structure. Substitute the measured mode and the calculated modal normalization coefficient into the formula to calculate the first two-order normalized mode matrices of the model cover plate structure.

[0136] Identify the measured displacement flexibility matrix of the model cover plate structure. Substitute the normalized mode matrix and the measured frequency into the formula D = φΛ -1 φ T , where to calculate the actual displacement flexibility matrix of the model cover plate structure.

[0137] Adopt the designed bending moment of the cover plate that controls the reinforcement of the mid-span section of the cover plate structure and combine it with the designed thickness of the cover plate, and use the formula to deduce that the designed vertical load F of the cover plate structure is 68.75 kN.

[0138] Calculate the modal displacement of the cover plate structure under the designed vertical load. Using the obtained measured displacement flexibility matrix of the cover plate structure and the deduced designed vertical load, substitute them into the formula S = DF to calculate that the modal displacement of the mid-span section of the cover plate structure is 5.86 mm.

[0139] Calculate the measured modal stiffness of the model cover plate structure. Substitute the modal displacement of the model cover plate structure and the designed vertical load of the pier into the formula to calculate that the modal stiffness of the cover plate structure is 11.73 kN / mm.

[0140] Calculate the design displacement and theoretical design stiffness of the cover plate structure under the action of the designed vertical load. Through the finite element model of the test cover plate structure, the design displacement of the mid-span section of the cover plate under the action of the designed vertical load is calculated to be 6.55 mm. Substitute the design displacement and the designed vertical load into the formula The theoretical design stiffness of the cover plate structure is calculated to be 10.50 kN / mm.

[0141] Calculate the dimensionless coefficient of the stiffness difference of the key section of the cover plate structure. Substitute the measured modal stiffness and the theoretical design stiffness at the mid-span of the cover plate into the formula The calculated

[0142] value of the dimensionless coefficient is 0.117, which is greater than 0, indicating that the actual stiffness state of the test cover plate structure meets the design requirements.

[0143] First, according to the actual situation of the existing cover plate structure, the cover plate structure to be detected is selected, the acceleration sensor layout scheme is formulated, the vibration acceleration time history response data of the cover plate structure under ambient excitation is collected, the basic modal parameters such as frequency and vibration mode of the cover plate structure are identified by the modal identification method, and then combined with the finite element model of the cover plate structure and the measured vibration mode is normalized, the measured displacement flexibility matrix of the cover plate structure is calculated, the modal displacement of the cover plate structure under the action of the designed vertical load is predicted, so as to determine the actual modal stiffness of the cover plate structure, and finally, the dimensionless coefficient of the difference between the actual modal stiffness and the theoretical design stiffness is used to judge whether the stiffness of the cover plate structure meets the design requirements.

[0144] Moreover, the present invention conducts a modal test on the cover plate structure of the subway operation depot, tests and identifies the vibration mode and frequency of the structure, then calculates the actual displacement flexibility matrix, predicts the modal displacement of the cover plate structure under the action of the designed vertical load, and then determines the modal stiffness of the key section of the cover plate structure, and then compares it with the theoretical design stiffness calculated by the finite element model of the cover plate structure, so as to achieve the purpose of evaluating the actual stiffness of the cover plate structure.

[0145] Based on the same technical concept, on the second aspect, the present invention also proposes a non-destructive detection device for the cover plate of existing buildings, including:

[0146] The equipment installation module is used to respectively install an acceleration detection device on a plurality of preset measurement points distributed at intervals in the preset detection area;

[0147] The standardized vibration mode matrix acquisition module is used to obtain the standardized vibration mode matrix of the cover plate structure according to the measured data collected by all the acceleration detection devices;

[0148] The measured modal stiffness acquisition module is used to obtain the measured modal stiffness of the cover plate according to the standardized vibration mode matrix;

[0149] A result output module, configured to obtain a dimensionless coefficient of the stiffness difference of the cover plate by using Formula 1 according to the measured modal stiffness and the theoretical design stiffness, and obtain a non-destructive testing result of the cover plate.

[0150] The non-destructive testing device for the existing building cover plate provided by the embodiment of the present application adopts the non-destructive testing method for the existing building cover plate in the above embodiment, and can solve the technical problem of how to establish a direct connection between basic modal test parameters and the structural stiffness of the upper cover plate of the operation depot of the subway vehicle depot. Compared with the prior art, the beneficial effects of the non-destructive testing device for the existing building cover plate provided by the embodiment of the present application are the same as those of the non-destructive testing method for the existing building cover plate provided by the above embodiment, and other technical features in the non-destructive testing device for the existing building cover plate are the same as the features disclosed in the method of the above embodiment, and will not be elaborated here.

[0151] Based on the same technical concept, in a third aspect, the present invention further provides a non-destructive testing device for an existing building cover plate. The non-destructive testing device for the existing building cover plate includes a processor and a memory, and an existing building cover plate non-destructive testing program is stored on the memory. When the existing building cover plate non-destructive testing program is executed by the processor, the non-destructive testing method for the existing building cover plate described in the first aspect is implemented.

[0152] Next, refer to Figure 5 , which shows a schematic structural diagram of a non-destructive testing device for an existing building cover plate suitable for implementing the embodiment of the present application. The non-destructive testing device for the existing building cover plate in the embodiment of the present application may include, but is not limited to, mobile terminals such as mobile phones, laptop computers, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions: tablet computers), PMPs (Portable Media Players), vehicle-mounted terminals (such as vehicle-mounted control terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc. Figure 5 The non-destructive testing device for the existing building cover plate shown is only an example, and should not bring any limitation to the functions and usage scope of the embodiment of the present application.

[0153] As Figure 5As shown, the non-destructive testing equipment for existing building covers may include a processing device 1001 (such as a central processing unit, a graphics processing unit, etc.), which can perform various appropriate actions and processes according to the program stored in the read-only memory (ROM: Read Only Memory) 1002 or the program loaded from the storage device 1003 into the random access memory (RAM: Random Access Memory) 1004. In the RAM 1004, various programs and data required for the operation of the non-destructive testing equipment for existing building covers are also stored. The processing device 1001, the ROM 1002, and the RAM 1004 are connected to each other through a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Generally, the following systems can be connected to the I / O interface 1006: an input device 1007 including, for example, a touch screen, a touchpad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; an output device 1008 including, for example, a liquid crystal display (LCD: Liquid Crystal Display), a speaker, a vibrator, etc.; a storage device 1003 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 1009. The communication device 1009 can allow the non-destructive testing equipment for existing building covers to communicate with other devices wirelessly or wiredly to exchange data. Although the figure shows a non-destructive testing equipment for existing building covers with various systems, it should be understood that it is not required to implement or have all the systems shown. More or fewer systems can be alternatively implemented or had.

[0154] In particular, according to the embodiments disclosed in the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, the embodiments disclosed in the present application include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program contains program codes for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from the network through the communication device, or installed from the storage device 1003, or installed from the ROM 1002. When the computer program is executed by the processing device 1001, the above functions defined in the method of the embodiments disclosed in the present application are executed.

[0155] The non-destructive testing equipment for existing building covers provided by the present application adopts the non-destructive testing method for existing building covers in the above embodiments, and can solve the technical problem of how to establish a direct connection between the basic modal test parameters and the structural stiffness of the upper cover of the operation depot of the subway vehicle depot. Compared with the prior art, the beneficial effects of the non-destructive testing equipment for existing building covers provided by the present application are the same as those of the non-destructive testing method for existing building covers provided by the above embodiments, and other technical features in the non-destructive testing equipment for existing building covers are the same as those disclosed in the method of the previous embodiment, and will not be elaborated here.

[0156] It should be understood that each part disclosed in this application can be implemented by hardware, software, firmware, or a combination thereof. In the description of the above embodiments, specific features, structures, materials, or characteristics can be combined in a suitable manner in any one or more embodiments or examples.

[0157] In addition, the non-destructive testing equipment for existing building covers provided in the embodiments of this application can solve the technical problem of how to establish a direct connection between the basic modal test parameters and the structural stiffness of the upper cover of the operation depot in the subway vehicle depot. Compared with the prior art, the beneficial effects of the non-destructive testing equipment for existing building covers provided in the embodiments of this application are the same as those of the non-destructive testing method for existing building covers provided in the above embodiments, and other technical features in the non-destructive testing equipment for existing building covers are the same as those disclosed in the above embodiment method, and will not be elaborated here.

[0158] Based on the same technical concept, in the fourth aspect, the present invention also proposes a non-destructive testing system for existing building covers, including:

[0159] The non-destructive testing equipment for existing building covers described in the third aspect; and,

[0160] A data acquisition device, which is installed in the area to be blasted in the tunnel, and the non-destructive testing equipment for existing building covers is communicatively connected to the data acquisition device and transmits the acquired data information to the non-destructive testing equipment for existing building covers.

[0161] In addition, the non-destructive testing system for existing building covers provided in the embodiments of this application can solve the technical problem of how to establish a direct connection between the basic modal test parameters and the structural stiffness of the upper cover of the operation depot in the subway vehicle depot. Compared with the prior art, the beneficial effects of the non-destructive testing system for existing building covers provided in the embodiments of this application are the same as those of the non-destructive testing method for existing building covers provided in the above embodiments, and other technical features in the non-destructive testing system for existing building covers are the same as those disclosed in the above embodiment method, and will not be elaborated here.

[0162] Based on the same technical concept, in the fifth aspect, the present invention also proposes a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by one or more processors, the non-destructive testing method for existing building covers described in the first aspect is implemented.

[0163] The computer-readable storage medium provided by the present application may, for example, be a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or components, or any combination of the above. More specific examples of the computer-readable storage medium may include, but are not limited to: electrical connections with one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM) or flash memory, optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the above. In this embodiment, the computer-readable storage medium may be any tangible medium that contains or stores a program, and the program may be used by or in conjunction with an instruction execution system, device, or component. The program code contained on the computer-readable storage medium may be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination of the above.

[0164] The above computer-readable storage medium may be included in the non-destructive testing equipment for existing building covers; or it may exist independently and not be assembled into the non-destructive testing equipment for existing building covers.

[0165] The above computer-readable storage medium carries one or more programs. When the one or more programs are executed by the non-destructive testing equipment for existing building covers, the non-destructive testing equipment for existing building covers can implement the non-destructive testing method for existing building covers described above.

[0166] Computer program code for performing the operations of this application can be written in one or more programming languages or combinations thereof. The above-mentioned programming languages include object-oriented programming languages such as Java, Smalltalk, C++, and also include conventional procedural programming languages such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, executed as a stand-alone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer can be connected to the user's computer through any kind of network, including a local area network (LAN) or a wide area network (WAN), or it can be connected to an external computer (for example, by using an Internet service provider to connect through the Internet).

[0167] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architectures, functions, and operations of systems, methods, and computer program products according to various embodiments of this application. In this regard, each box in the flowchart or block diagram may represent a module, a program segment, or a part of the code, and this module, program segment, or part of the code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the boxes may occur in a different order than those marked in the accompanying drawings. For example, two consecutively represented boxes may actually be executed substantially in parallel, and they may sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart, and the combination of boxes in the block diagram and / or flowchart, can be implemented by a dedicated hardware-based system for performing the specified functions or operations, or can be implemented by a combination of dedicated hardware and computer instructions.

[0168] The modules involved in the embodiments of this application can be implemented in software or in hardware. Among them, the name of the module does not constitute a limitation on the unit itself in some cases.

[0169] The readable storage medium provided by this application is a computer-readable storage medium. The computer-readable storage medium stores computer-readable program instructions (i.e., computer programs) for performing the above-mentioned non-destructive detection method for existing building covers, and can solve the technical problem of how to improve the gear control accuracy of PTC. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided by this application are the same as those of the non-destructive detection method for existing building covers provided by the above embodiments, and will not be elaborated here.

[0170] The above are only some embodiments of the present application, and do not limit the patent scope of the present application. Any equivalent structural transformation made under the technical concept of the present application by using the content of the specification and drawings of the present application, or any direct / indirect application in other related technical fields, is included in the patent protection scope of the present application.

Claims

1. A non-destructive testing method for the cover plate of an existing building, characterized in that, It includes the following steps: Install an acceleration detection device respectively on multiple preset measuring points distributed at intervals in the preset detection area of the existing cover plate structure; Obtain the standardized mode shape matrix of the cover plate structure according to the measured data such as the mode shape and frequency collected by all the acceleration detection devices; Obtain the measured modal stiffness of the cover plate according to the standardized mode shape matrix; According to the measured modal stiffness and the theoretical design stiffness, use Formula 1 to obtain the dimensionless coefficient of the stiffness difference of the cover plate, and obtain the non-destructive test result of the cover plate; wherein, Formula 1 is: λ is the dimensionless coefficient of the stiffness difference, K1 is the measured modal stiffness, and K2 is the theoretical design stiffness.

2. The non-destructive testing method for the cover plate of existing buildings according to claim 1, characterized in that, The step of obtaining the standardized mode shape matrix of the cover plate structure according to the measured data collected by all the acceleration detection devices includes: Calculate the standardized coefficient of the cover plate according to the measured data collected by all the acceleration detection devices by using Formula 2; wherein, Formula 2 is: γ i is the said normalization coefficient, M a is the mass matrix of the said cover plate, is the i-th measured mode shape column vector of the said cover plate, is the said transpose vector; Calculate the standard mode shape of the cover plate according to the standardized coefficient by using Formula 3; wherein, Formula 3 is: is the column vector of the i-th order normalized mode shape matrix, is the column vector of the i-th order measured mode shape of the cover plate, γ i is the normalization coefficient.

3. The non-destructive testing method for the cover plate of existing buildings according to claim 2, characterized in that, The step of obtaining the measured modal stiffness of the cover plate according to the standardized mode shape matrix includes: According to the standardized mode shape matrix, and in combination with the predicted modal displacement matrix of the cover plate and the deduced design vertical load of the cover plate, calculate and obtain the measured modal stiffness of the cover plate by using Formula 5; wherein, Formula 5 is: K1 is the measured modal stiffness, F is the design vertical load, and ε is the modal displacement matrix.

4. The non-destructive testing method for the cover plate of existing buildings according to claim 3, wherein, The step of calculating and obtaining the measured modal stiffness of the cover plate according to the standardized mode shape matrix, and in combination with the predicted modal displacement matrix of the cover plate and the deduced design vertical load of the cover plate by using Formula 5 includes: Calculate the measured displacement amplitude matrix of the cover plate according to the standardized mode shape matrix by using Formula 6; wherein, Formula 6 is: φ is the standardized mode shape matrix, φ T is the transpose matrix of φ, ω i is the i-th order modal frequency; Deduce the vertical load of the cover plate according to the preset bending moment of the cover plate; According to the measured displacement flexibility matrix and the vertical load, calculate and predict the modal displacement matrix by using Formula 7; wherein, Formula 7 is: S = DF, S is the modal displacement matrix, D is the measured displacement flexibility matrix, and F is the design vertical load; In combination with the modal displacement matrix and the design vertical load, calculate and obtain the measured modal stiffness of the cover plate by using Formula 5.

5. The non-destructive testing method for the existing building cover plate according to claim 4, characterized in that After calculating and obtaining the measured modal stiffness of the cover plate by using Formula 5 in combination with the modal displacement matrix and the design vertical load, it further includes: Calculate the design displacement of the cover plate under the action of the vertical load, and in combination with the vertical load, calculate and obtain the theoretical design stiffness of the cover plate by using Formula 8; wherein, Formula 8 is: K2 is the theoretical design stiffness of the cover plate, D is the measured displacement flexibility matrix, F is the design vertical load, and S is the modal displacement matrix.

6. The non-destructive testing method for the existing building cover plate according to any one of claims 1 to 5, characterized in that Before the step of respectively installing an acceleration detection device on a plurality of preset measurement points spaced apart from each other in the preset detection area, the method further includes: Setting the preset detection area on the cover plate according to the actual service state of the cover plate and the actual construction conditions in the area where the cover plate is located; Calculating the theoretical vibration mode of the cover plate according to the preset completion data of the cover plate; Setting a plurality of spaced-apart preset measurement points in the preset detection area according to the theoretical vibration mode and the key cross-sections of the cover plate; wherein, the key cross-sections are the mid-span cross-section of the cover plate and / or the cross-section where the plate thickness changes and / or the beam-plate connection cross-section.

7. A non-destructive testing device for existing building cover plates, characterized in that, It includes: An equipment installation module for respectively installing an acceleration detection device on a plurality of spaced-apart preset measurement points in the preset detection area; A standardized vibration mode matrix acquisition module for acquiring the standardized vibration mode matrix of the cover plate structure according to the measured data collected by all the acceleration detection devices; A measured modal stiffness acquisition module for acquiring the measured modal stiffness of the cover plate according to the standardized vibration mode matrix; A result output module for obtaining the non-dimensionalized coefficient of the stiffness difference of the cover plate and obtaining the non-destructive testing result of the cover plate by using Formula 1 according to the measured modal stiffness and the theoretical design stiffness.

8. A non-destructive testing device for the cover plate of existing buildings, characterized in that, The existing building cover plate non-destructive testing equipment includes a processor and a memory, and an existing building cover plate non-destructive testing program is stored on the memory. When the existing building cover plate non-destructive testing program is executed by the processor, the existing building cover plate non-destructive testing method according to any one of claims 1 to 6 is implemented.

9. A non-destructive testing system for existing building covers, characterized in that, It includes: The existing building cover plate non-destructive testing equipment according to claim 8; And, A data acquisition device, which is installed in the area to be blasted in the tunnel, and the existing building cover plate non-destructive testing equipment is communicatively connected to the data acquisition device and transmits the collected data information to the existing building cover plate non-destructive testing equipment.

10. A computer-readable storage medium, characterized in that, A computer program is stored on the storage medium, and when the computer program is executed by one or more processors, the existing building cover plate non-destructive testing method according to any one of claims 1 to 6 is implemented.

11. A sensor installation and fixation protection device, characterized in that, The acceleration sensor protection device mainly includes a protection device fixing plate, a sensor fixing plate and a sensor protection device. There are four bolt holes on the protection device for fixing the protection device to the structure to be detected. There are six bolt holes on the sensor fixing plate for fixing the sensor. The sensor protection device is mainly composed of four protection plates on the front, back, left and right, which plays a protective role for the sensor during use. The sensor protection device is made of a lightweight and high-strength alloy material, has the function of simple and rapid installation and removal, and is more conducive to realizing the accuracy of the non-destructive testing results of the existing cover plate structure according to claims 1 to 6.

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