A method and system for monitoring and safety assessment of historical and cultural building data

Abstract

The present invention relates to the field of building safety technology, and specifically to a historical and cultural building data monitoring and safety assessment method and system thereof, including loading different levels of white noise excitation on the structure of the target building, and obtaining the excitation response of each structure; calculating the safety evaluation value of each structure at each level based on multiple excitation responses of each structure; fitting all safety evaluation values ​​of each structure to obtain the fitting function corresponding to each structure; calculating the target safety evaluation index of each structure under a preset earthquake level according to the fitting function; and obtaining the evaluation result of the target building according to the target safety evaluation index of each structure. The present invention evaluates the structural integrity and end state of the beams and columns of the building through excitation loading, and determines the evaluation result of the lower limit of the confidence interval in combination with reliability analysis, which can reflect the vibration response state of the building facing external impact.

Description

Technical Field

[0001] The present invention relates to the field of building safety technology, and in particular to a historical and cultural building data monitoring and safety assessment method and system thereof. Background Art

[0002] Historical and cultural buildings are not only the treasures of human civilization, they also carry rich historical, cultural and artistic values, and are an important part of the city's landscape and regional characteristics. However, existing historical and cultural buildings often face many challenges, especially because they were built a long time ago and many architectural drawings have been lost. Therefore, it becomes extremely difficult to calculate the structural internal forces and bearing capacity of these historical and cultural buildings.

[0003] In addition, existing assessment methods often use static analysis. Although this analysis method can provide some basic data to a certain extent, it cannot effectively evaluate the impact of external loads on structural safety performance. External loads include natural factors such as wind, rain, earthquakes, etc., as well as human factors such as traffic vibration and tourist load. These factors have a direct or indirect impact on the structural safety of historical buildings, but static analysis methods often cannot fully consider these dynamically changing factors.

[0004] Therefore, there is an urgent need for a method that can effectively conduct safety assessments on historical and cultural buildings. Summary of the invention

[0005] In order to solve the above technical problems, the purpose of the present invention is to provide a method and system for monitoring and safety assessment of historical and cultural building data. In order to achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0006] In a first aspect, the present application provides a method for data monitoring and safety assessment of historical and cultural buildings, the method comprising: performing white noise excitation loading of different levels on the excitation points of multiple structures of a target building, and obtaining the excitation response of each structure, each level corresponding to an acceleration amplitude; calculating the safety evaluation value of each structure at each level based on the multiple excitation responses of each structure; fitting a preset function formula according to all the safety evaluation values ​​of each structure to obtain a fitting function formula corresponding to each structure; calculating the target safety evaluation index of each structure under a preset earthquake level according to the fitting function formula; and obtaining the evaluation result of the target building according to the target safety evaluation index of each structure.

[0007] In combination with the first aspect, in a possible implementation method, the degree of vibration correlation is calculated based on the amplitude change of the coherence function corresponding to each monitoring point, including: calculating a first amplitude mean based on the amplitude of each coherence function in the time domain; calculating the degree of vibration correlation based on the amplitude mean corresponding to each monitoring point and a first preset formula.

[0008] In combination with the first aspect, in a possible implementation method, the instantaneous amplitude change degree is calculated based on the amplitude change of the cross-correlation function corresponding to each monitoring point, including: calculating the second amplitude mean according to the amplitude of each cross-correlation function in the time domain; calculating the instantaneous amplitude change degree based on the amplitude mean corresponding to each monitoring point and the second preset formula.

[0009] In combination with the first aspect, in a possible implementation method, the evaluation result of the target building is obtained according to the target safety evaluation index analysis of each structure, including: solving the preset Weibull distribution according to all the target safety evaluation indicators to obtain the performance index; calculating the evaluation value of the target building within a credible interval based on the performance index and all the target safety evaluation indicators; and obtaining the evaluation result of the target building based on the evaluation value.

[0010] In the second aspect, the present application also provides a historical and cultural building data monitoring and safety assessment system, including: an excitation module, used to load white noise excitation at different levels to the excitation points of multiple structures of the target building, and obtain the excitation response of each of the structures, each of the levels corresponding to an acceleration amplitude; a response calculation module, used to calculate the safety evaluation value of each structure at each level based on the multiple excitation responses of each structure; a fitting module, used to fit a preset function formula according to all the safety evaluation values ​​of each structure to obtain a fitting function formula corresponding to each structure; a fitting function calculation module, used to calculate the target safety evaluation index of each structure under a preset earthquake level according to the fitting function formula; an analysis module, used to analyze the target safety evaluation index of each structure to obtain the evaluation result of the target building.

[0011] In combination with the second aspect, in a possible implementation, the excitation response includes acceleration response data of three monitoring points, the excitation point and all the monitoring points are on a straight line, and the response calculation module includes: a preprocessing module, used to preprocess the excitation response of a level and the preset excitation data corresponding to the level to obtain preprocessed data; a function module, used to calculate the frequency response function, coherence function and cross-correlation function corresponding to each monitoring point in sequence according to the preprocessed data; a frequency response calculation module, used to calculate the frequency response consistency degree based on the frequency response function difference between adjacent monitoring points; a vibration calculation module, used to calculate the vibration correlation degree based on the amplitude change of the coherence function corresponding to each of the monitoring points; an amplitude calculation module, used to calculate the instantaneous amplitude change degree based on the amplitude change of the cross-correlation function corresponding to each of the monitoring points; a comprehensive calculation module, used to calculate the frequency response consistency degree, vibration consistency degree and instantaneous consistency degree based on the fuzzy comprehensive evaluation method to obtain a safety evaluation value.

[0012] In combination with the second aspect, in a possible implementation method, the vibration calculation module includes: a first mean calculation module, used to calculate a first amplitude mean according to the amplitude of each coherence function in the time domain; a first function calculation module, used to calculate the degree of vibration correlation based on the amplitude mean corresponding to each monitoring point and a first preset formula.

[0013] In combination with the second aspect, in a possible implementation, the amplitude calculation module includes: a second mean calculation module, used to calculate the second amplitude mean according to the amplitude of each of the cross-correlation functions in the time domain; a second function calculation module, used to calculate the instantaneous amplitude change degree based on the amplitude mean corresponding to each monitoring point and a second preset formula.

[0014] In combination with the second aspect, in a possible implementation, the analysis module includes: an indicator calculation module, used to solve the preset Weibull distribution according to all the target safety evaluation indicators to obtain a performance indicator; a trusted calculation module, used to calculate the evaluation value of the target building within a trusted interval based on the performance indicator and all the target safety evaluation indicators; and an evaluation module, used to determine the evaluation result of the target building based on the evaluation value.

[0015] The present invention has the following beneficial effects:

[0016] In the present invention, by applying excitation loading to the beams and columns of the target building respectively, based on the changes in their vibration responses, combined with the three dimensions of frequency response consistency, vibration correlation and instantaneous amplitude response, a comprehensive judgment is made on the integrity of the internal structure of the building and the restraint state of its ends, so as to achieve the assessment target of the beams and columns. And through the above-mentioned non-invasive historical and cultural building health monitoring method, combined with reliability analysis, the assessment value of the target building at the lower limit of the confidence interval is confirmed, which effectively improves the reliability of the results. This method can effectively deal with the problem of difficulty in calculating structural internal forces and bearing capacity in the absence of architectural drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 A schematic flow chart of a method for monitoring and safety assessment of historical and cultural building data provided in Example 1 of the present invention;

[0019] Figure 2 A schematic flow chart of step S2 provided in Example 1 of the present invention;

[0020] Figure 3 A schematic flow chart of step S5 provided in Example 1 of the present invention;

[0021] Figure 4 This is a schematic diagram of the structure of the historical and cultural building data monitoring and safety assessment system described in Example 2 of the present invention. DETAILED DESCRIPTION

[0022] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following is a detailed description of a method and system for monitoring and safety assessment of historical and cultural building data proposed by the present invention, its specific implementation method, structure, features and effects, in combination with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures or characteristics in one or more embodiments may be combined in any suitable form.

[0023] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0024] Embodiment 1:

[0025] The specific scheme of the historical and cultural building data monitoring and safety assessment method provided by the present invention is described in detail below with reference to the accompanying drawings.

[0026] See also Figure 1 , which shows a schematic diagram of a process of historical and cultural building data monitoring and safety assessment provided by an embodiment of the present invention, wherein this embodiment includes steps S1 to S4 in total.

[0027] S1. Apply white noise excitation loading of different levels to excitation points of multiple structures of a target building, and obtain the excitation response of each structure, wherein each level corresponds to an acceleration amplitude.

[0028] Since the object of this embodiment is historical and cultural buildings, such buildings are usually composed of a series of columns and beams combined in a specific structural manner. Therefore, the structures referred to in this embodiment mainly refer to these columns and beams. When setting the excitation points, it is usually selected to be done at the ends of these structures. Specifically, for the columns, the excitation points are set at their bottom positions, and for the beams, the excitation points can be any end.

[0029] Meanwhile, regarding the white noise excitation mentioned in the present embodiment, the white noise excitation is applied for more than 30 seconds by the variable frequency vibration motor. In order to realize this process, those skilled in the art can use simulink software to generate Gaussian white noise, and set the acceleration amplitudes of four levels of Gaussian white noise respectively, which are 0.01g, 0.02g, 0.03g and 0.04g. In addition, the vibration amplitude limit of the variable frequency vibration motor recommended for use can reach 0.05g. It is worth noting that when the earthquake magnitude is 6, the corresponding peak acceleration is about 0.05g, and the seismic resistance level of all buildings is higher than 6. Therefore, the vibration acceleration generated in the test is only equivalent to 80% of the acceleration amplitude corresponding to the 6-level seismic resistance level, and such a test will not cause any damaging effect on the building.

[0030] If the target building is found to be in a relatively dangerous state in the preliminary assessment, the level or amplitude of the Gaussian white noise can be flexibly adjusted by a person skilled in the art. For example, other numerical sequences that increase in sequence can be used, such as [0.01, 0.015, 0.02, 0.025] or [0.012, 0.014, 0.016, 0.018], etc. These increasing acceleration amplitude sequences can also be selected according to actual conditions. In this embodiment, no specific restrictions are made on these selections.

[0031] In addition, in the present embodiment, the vibration response of the structure is collected by acceleration sensors, which are wireless and have a sampling frequency of 2000 Hz. The sampling duration is equal to the duration of the white noise excitation application. When laying out these acceleration sensors, priority is given to the equal spacing setting, and they are placed at the four equal points of the structure. In other words, in the present embodiment, three monitoring points are set on each structure, and these three monitoring points are respectively located at the four equal points of the structure and are located on a straight line. According to the distance from the excitation point, these three monitoring points are respectively referred to as monitoring point No. 1, monitoring point No. 2 and monitoring point No. 3.

[0032] S2. Calculate the safety evaluation value of each structure at each level based on the multiple stimulus responses of each structure.

[0033] In this embodiment, the excitation response of the structure when it is subjected to external load is taken into consideration. The excitation response of the structure under the external load shows obvious differences.

[0034] Specifically, if the frequency response of the monitoring points of a structure is inconsistent under external loads, this usually means that the physical properties of the structure, such as stiffness, mass or damping, have changed. For example, in the case of wooden materials, such changes may be caused by structural defects such as internal borer corrosion or decay caused by improper maintenance.

[0035] Furthermore, if the vibration correlation of the monitoring points of the structure is poor under the action of external loads, it may indicate that there are differences in the stiffness, mass distribution and damping characteristics of different parts of the structure. Such differences will lead to inconsistent responses of different parts when vibration is excited, thus reflecting the structural defects of the structure.

[0036] In addition, if the structure has a good transient amplitude response at the monitoring point under the external load, it usually means that the end of the structure is less constrained from other structures. This further proves that there are differences in stability between structures.

[0037] In order to comprehensively evaluate the stability of the structure, this embodiment adopts a three-dimensional analysis method: frequency response consistency of the monitoring points, instantaneous amplitude changes, and vibration correlation. Figure 2 , which shows the calculation process of the safety evaluation value of the nth structure in the historical and cultural building at the level of acceleration amplitude p. For detailed steps, please refer to step S21 to step S26.

[0038] S21 , preprocessing the stimulus response of a level and the preset stimulus data corresponding to the level to obtain preprocessed data.

[0039] It should be noted that the preset excitation data mentioned in this step is Gaussian white noise with different acceleration amplitudes corresponding to different levels.

[0040] At the same time, the preprocessing mentioned in this step is to use polynomials to remove trend items, thereby reducing zero drift and environmental interference, and ensuring that the baseline always hovers around 0. Specifically, those skilled in the art can use filtering method, polynomial fitting method, wavelet decomposition and moving average method and other trend item preprocessing removal methods.

[0041] At the same time, in this embodiment, a method of minimizing the sum of squared errors is provided for preprocessing, as shown in the following formula:

[0042]

[0043] Among them, A n,m,p (t) represents the pre-processed acceleration response data of the mth point of the nth structure at the level of acceleration amplitude p; It represents the acceleration response data of the mth point of the nth structure before preprocessing at the level of acceleration amplitude p; t represents time; Q represents the sampling frequency of the acceleration sensor; W represents the sampling time or the time of applying white noise vibration.

[0044] In the above calculation formula, m∈[1,2,3], where 1 represents monitoring point 1 which is closest to the vibration point; similarly, 3 represents monitoring point 3 which is farthest from the vibration point; and 2 represents monitoring point 2 which is located between monitoring point 1 and monitoring point 3. The above calculation process can also be used for the preset excitation data, which will not be described in detail in this embodiment.

[0045] S22. Calculate the frequency response function, coherence function and cross-correlation function corresponding to each monitoring point in sequence according to the preprocessed data.

[0046] Specifically, the frequency response function is calculated as follows:

[0047]

[0048] Among them, F n,m,p (t) represents the frequency response function corresponding to the mth point of the nth structure at the level of acceleration amplitude p; t represents time; X i,n,m,p (k) represents the number of segments J for A n,m,p (t) the result of performing fast Fourier transform on the i-th data segment; Represents X i,n,m,p The conjugate complex number of (k); Y i,n,0,p (k) represents the number of segments J for A n,0,p(t) The result of fast Fourier transform of the i-th data segment; A n,0,p (t) represents the preset excitation data after preprocessing of the excitation point of the nth structure at the level of acceleration amplitude p.

[0049] In the above calculation formula, it is worth noting that the number of segments J is affected by the characteristics of the acceleration response data itself. For example, factors such as the acquisition length, frequency components and noise level of the acceleration response data will affect the selection of the number of segments. Longer signals can be divided into more segments, while shorter or noisier signals may require fewer segments to avoid information loss caused by excessive segmentation. Generally, it can be divided into 100 segments or more. The specific number of segments can be modified according to actual conditions by the technical field in this field, and no specific restrictions are made in this embodiment.

[0050] Specifically, the coherence function is calculated as follows:

[0051]

[0052] Among them, G n,m,p (t) represents the coherence function corresponding to the mth point of the nth structure at the level of acceleration amplitude p; t represents time; X i,n,m,p (k) represents the number of segments J for A n,m,p (t) the result of performing fast Fourier transform on the i-th data segment; Represents X i,n,m,p The conjugate complex number of (k); Y i,n,0,p (k) represents the number of segments J for A n,0,p (t) the result of performing fast Fourier transform on the i-th data segment; Represents Y i,n,0,p The conjugate complex number of (k); A n,0,p (t) represents the preset excitation data after preprocessing of the excitation point of the nth structure at the level of acceleration amplitude p.

[0053] Specifically, the cross-correlation function is calculated as follows:

[0054]

[0055] Among them, T n,m,p (t) represents the cross-correlation function corresponding to the mth point of the nth structure at the level of acceleration amplitude p; t represents time; Q represents the sampling frequency of the acceleration sensor; W represents the sampling time or the time of applying white noise vibration; A n,m,p (t represents the acceleration response data of the mth point of the nth structure after preprocessing at the level of acceleration amplitude p; A n,0,p(t represents the preset excitation data after preprocessing of the excitation point of the nth structure at the level of acceleration amplitude p.

[0056] S23, calculating the frequency response consistency based on the frequency response function differences between adjacent monitoring points.

[0057] Furthermore, in this step, the frequency response consistency is obtained by the following calculation:

[0058]

[0059] Among them, f n,p Indicates the frequency response consistency of the nth structure at the level of acceleration amplitude p; Cov represents covariance operation; Var represents variance operation; F n,1,p (t) represents the frequency response function corresponding to the first monitoring point of the nth structure at the level of acceleration amplitude p; F n,2,p (t) represents the frequency response function corresponding to the second monitoring point of the nth structure at the level of acceleration amplitude p; F n,3,p (t) represents the frequency response function corresponding to the 3rd monitoring point of the nth structure at the level of acceleration amplitude p.

[0060] In the above calculation formula, the frequency response function is introduced to specifically describe and reflect the relationship between the structure at each monitoring point and the excitation point. The frequency response function is used to reflect the response characteristics of the structure at different frequencies. When it is observed that the amplitude expression of a certain monitoring point in the frequency domain is significantly different from that of the excitation point, this difference will be manifested as a decrease in the mean value in the amplitude of the frequency response function. This change can reflect that the structure has changed in characteristics such as stiffness, mass or damping.

[0061] In other words, if the structure is made of wood, then a decrease in the amplitude of the frequency response function may indicate some potential problems inside. These problems may include woodworm infestation, which reduces the strength and stability of the wood structure; or it may be due to improper maintenance, causing the wood material to decay, thus affecting the integrity and durability of the structure. These structural defects will not only weaken the performance of the material, but may also pose a threat to the safety and reliability of the entire structure.

[0062] S24. Calculate the vibration correlation degree based on the amplitude change of the coherence function corresponding to each monitoring point.

[0063] Specifically, this step includes the following steps to calculate the vibration correlation degree:

[0064] S241. Calculate a first amplitude mean value according to the amplitude of each coherence function in the time domain.

[0065] That is, in this step, according to G n,1,p (t), G n,2,p (t) and G n,3,p (t) The amplitude in the time dimension t is averaged to obtain the amplitude mean of the coherence function corresponding to the monitoring points 1, 2 and 3 of the nth structure at the acceleration level p. and

[0066] S242. Calculate the vibration correlation degree based on the amplitude mean value corresponding to each monitoring point and a first preset formula.

[0067] Furthermore, in this step, the first preset formula is as follows:

[0068]

[0069] Among them, z n,p It indicates the vibration correlation degree of the nth structure at the level of acceleration amplitude p; It represents the mean amplitude of the coherence function corresponding to the monitoring point No. 1 of the nth structure at the level of acceleration amplitude p; It represents the mean amplitude of the coherence function corresponding to the monitoring point No. 2 of the nth structure at the level of acceleration amplitude p; It represents the mean amplitude of the coherence function corresponding to the monitoring point No. 3 of the nth structure at the level of acceleration amplitude p.

[0070] In the above calculation formula, the change in the amplitude of the coherence function curve can reveal the interaction between the monitoring point and the excitation point of the structure. If there is a significant difference in the correlation between the excitation response of a certain monitoring point and the white noise excitation of the excitation point, the difference will be reflected in the amplitude of the coherence function as a decrease in the mean. This phenomenon can reflect whether the stiffness, mass or damping characteristics of the structure have changed. In other words, for wooden materials, there may be structural defects such as decay caused by borers or improper maintenance.

[0071] S25. Calculate the instantaneous amplitude change degree based on the amplitude change of the cross-correlation function corresponding to each monitoring point.

[0072] Specifically, this step includes the following steps to calculate the instantaneous amplitude change degree:

[0073] S251. Calculate a second amplitude mean value according to the amplitude of each cross-correlation function in the time domain.

[0074] That is, in this step, according to T n,1,p (t), Tn,2,p (t) and T n,3,p (t) The amplitude in the time dimension t is averaged to obtain the average amplitude of the cross-correlation function corresponding to the monitoring point 1, monitoring point 2 and monitoring point 3 of the nth structure at the level of acceleration p. and

[0075] S252. Calculate the instantaneous amplitude change degree based on the amplitude mean corresponding to each monitoring point and the second preset formula.

[0076] Furthermore, in this step, the second preset formula is as follows:

[0077]

[0078] Among them, e n,p It indicates the instantaneous amplitude change degree of the nth structure under the level of acceleration amplitude p; It represents the mean value of the cross-correlation function amplitude corresponding to the monitoring point No. 1 of the nth structure at the level of acceleration amplitude p; It represents the mean value of the cross-correlation function amplitude corresponding to the monitoring point No. 2 of the nth structure at the level of acceleration amplitude p; It represents the mean value of the cross-correlation function amplitude corresponding to the monitoring point No. 3 of the nth structure at the level of acceleration amplitude p.

[0079] In the above calculation formula, the instantaneous amplitude dependence of the structure between the monitoring point and the excitation point is reflected by analyzing the amplitude change of the cross-correlation function. If the excitation response of the monitoring point is significantly dependent on the instantaneous amplitude of the white noise excitation of the excitation point, it will be reflected in the amplitude of the cross-correlation function, and the mean value will increase. This phenomenon shows that the ends of the structure are relatively weak under the constraints of other structures, which proves that the stability between the structures is poor. Under external excitation, the structure is prone to vibration, especially when the acceleration amplitude is large, the risk of collapse increases. Therefore, by analyzing the amplitude change of the cross-correlation function, the stability and safety of the structure under external excitation can be evaluated, providing an important reference for structural design and maintenance.

[0080] S26. Calculate the frequency response consistency, vibration consistency and instantaneous consistency based on a fuzzy comprehensive evaluation method to obtain a safety evaluation value.

[0081] Specifically, the formula for calculating the safety evaluation value using the fuzzy comprehensive evaluation method in this step is as follows:

[0082]

[0083] Among them, P n,prepresents the safety evaluation value of the nth structure at the level of acceleration amplitude p; f n,p Indicates the frequency response consistency of the nth structure at the level of acceleration amplitude p; z n,p represents the vibration correlation degree of the nth structure at the level of acceleration amplitude p; e n,p Indicates the instantaneous amplitude change of the nth structure at the level of acceleration amplitude p.

[0084] S3. According to all the safety evaluation values ​​of each structure, a preset function is fitted to obtain a fitting function corresponding to each structure.

[0085] Specifically, the preset function in this embodiment is:

[0086]

[0087] Among them, P n,p represents the safety evaluation value of the nth structure at the level of acceleration amplitude p; a, b, c and d represent the parameters to be fitted; p represents the acceleration amplitude.

[0088] In the preset function mentioned above, in the process of curve change, it shows a trend of first being stable and then gradually rising. This change pattern can very effectively reflect the performance of the structure under the influence of gradually increasing acceleration amplitude. Specifically, when the acceleration amplitude gradually increases, the response of the structure does not become drastic immediately, but remains relatively stable in an initial stage, and then begins to gradually rise. This phenomenon is well reflected in the fitting process, and the fitting effect is good. Through this preset function, the dynamic behavior of the structure under the expected acceleration amplitude can be more accurately predicted and analyzed.

[0089] S4. Calculate the target safety evaluation index of each structure under a preset earthquake level according to the fitting function.

[0090] It should be noted that in this embodiment, the focus is on whether the target building can withstand a magnitude 6 earthquake and maintain its structural integrity. Therefore, in this step, the earthquake level is preset to be 6, and its acceleration peak is 0.5g. That is, 0.5g is substituted into the fitting function to calculate the target safety evaluation index of each structure under a magnitude 6 earthquake.

[0091] S5. Analyze the target safety evaluation index of each structure to obtain the evaluation result of the target building.

[0092] In this embodiment, by sequentially executing steps S1 to S4, the structural evaluation results of the target building under the action of a magnitude 6 earthquake can be obtained. For professionals in this field, there are a variety of methods that can be used to obtain the evaluation results of the target building. For example, the minimum value can be screened out from all target safety evaluation indicators, and then it is determined whether the minimum value is lower than a predetermined threshold. If the minimum value is lower than the threshold, the structure corresponding to the minimum value needs to be immediately strengthened, or the structures with smaller target safety evaluation indicators need to be inspected to ensure that they are in good condition. If the minimum value is not lower than the threshold, it can be considered that the target building does not need maintenance. In addition, an average value can be calculated based on all target safety evaluation indicators to obtain a mean value. Subsequently, by determining whether the mean value is lower than the threshold, it is determined whether the structure corresponding to the minimum value needs to be strengthened, or the structures with smaller target safety evaluation indicators need to be inspected, or it is confirmed that the target building does not need maintenance. Both methods can effectively evaluate the safety of the target building under earthquake action and guide subsequent structural strengthening and maintenance work.

[0093] At the same time, this embodiment also provides a method for calculating the target safety evaluation index based on the building reliability, see Figure 3 , the figure shows that step S5 specifically includes steps S51 to S53.

[0094] S51. Solve the preset Weibull distribution according to all the target safety evaluation indicators to obtain performance indicators.

[0095] Specifically, in this embodiment, the fault-free data analysis when the shape parameters are unknown under the Weibull distribution is relied on, and the reliability is 0.8 and the confidence level is 0.8 as the basis for the preset Weibull distribution. The preset Weibull distribution is specifically as follows:

[0096]

[0097] Among them, K n represents the safety evaluation index of the nth structure under a magnitude 6 earthquake with an acceleration amplitude of 0.05; N represents the total number of structures; r represents the performance index; ln represents a logarithmic function with a natural constant as the base.

[0098] It should be noted that those skilled in the art can use the dichotomy method to solve the above calculation formula.

[0099] S52: Calculate the evaluation value of the target building within a credible interval based on the performance index and all the target safety evaluation indexes.

[0100] The calculation formula for the evaluation value mentioned in this step is as follows:

[0101]

[0102] Where K represents the evaluation value of the nth structure under a magnitude 6 earthquake with an acceleration amplitude of 0.05; N represents the total number of structures; K n represents the safety evaluation index of the nth structure under a magnitude 6 earthquake with an acceleration amplitude of 0.05; r represents the performance index; ln represents a logarithmic function with a natural constant as the base.

[0103] Through the above calculation formula, this embodiment can calculate the evaluation value corresponding to the reliable life of the target building at the lower confidence limit through the Weibull distribution of the safety evaluation index corresponding to multiple structures. And in the subsequent steps, it is used to determine whether the target building needs maintenance. For details, please refer to step S53.

[0104] S53: Obtain an evaluation result of the target building based on the evaluation value.

[0105] Through step S51 and step S52, the evaluation value of the target building can be calculated, and those skilled in the art can use the result of this quantitative calculation as the basis for evaluating the target building. For example, this embodiment provides an exemplary judgment method:

[0106] 1. When 0<K<0.2, the target building is in an extremely dangerous state and its safety is extremely low. Recommended treatment measures: Stop using it immediately to ensure the safety of personnel. Organize a professional team to conduct a detailed safety assessment to determine the source of danger and the extent of damage. According to the assessment results, formulate an emergency reinforcement or reconstruction plan and implement it as soon as possible. Strengthen monitoring to prevent the situation from further deteriorating.

[0107] 2. When 0.2≤K<0.4, the safety of the target building is poor and there are obvious safety hazards. Recommended treatment measures: limit use to avoid further damage to the structure. Conduct detailed structural inspections to determine the location and extent of damage. Develop targeted reinforcement and repair plans and implement them as soon as possible. Strengthen daily maintenance and management to ensure building safety.

[0108] 3. When 0.4≤K<0.6, the target building is generally safe, but there are some potential safety hazards. Recommended treatment measures: Strengthen daily monitoring and maintenance to promptly discover and deal with potential problems. Perform local reinforcement and repair of damaged parts to ensure structural stability. Consider overall reinforcement or renovation of the building to improve safety. Strengthen safety education and training to improve the safety awareness of managers and users.

[0109] 4. When 0.6≤K<0.8, the target building is relatively safe, but potential problems still need to be paid attention to. Recommended treatment measures: Conduct safety inspections and assessments regularly to ensure building safety. Repair and handle potential problems found in a timely manner. Strengthen the use management of buildings to avoid damage to the structure caused by improper use. Consider maintaining and preserving the building to extend its service life.

[0110] 5. When 0.8≤K<1, the target building is highly safe and in good condition. Recommended treatment measures: Continue to conduct regular safety inspections and assessments to ensure building safety. Strengthen daily maintenance and management of buildings to keep them in good condition. Carry out necessary maintenance and repairs on buildings to extend their service life. Strengthen safety publicity and education to improve the safety awareness of managers and users.

[0111] It should be noted that the above judgment method is an exemplary distance, and those skilled in the art can change different value ranges according to actual needs to obtain the safety evaluation result of the target building. This embodiment does not make specific restrictions on this.

[0112] In the above embodiment, by applying excitation loading to the beams and columns of the target building respectively, and judging the integrity of the internal structure and the restraint state of the ends according to the changes in the vibration responses of the beams and columns, the three dimensions of frequency response consistency, vibration correlation and instantaneous amplitude response, the purpose of comprehensive evaluation of the columns and beams is achieved. By combining reliability analysis, it is confirmed that the evaluation value of the target building at the lower limit of the confidence interval is obtained, which can effectively improve the reliability of the final result. Compared with the existing static analysis method, this embodiment adopts a dynamic monitoring method, which can more effectively reflect the vibration performance of the target building caused by external impacts such as ground and ground traffic, blasting, strong winds, heavy rains, earthquakes, etc. This method can effectively overcome the problem that it is difficult to calculate the structural internal forces and bearing capacity of the target building without architectural drawings, thereby providing a more accurate and comprehensive basis for the safety assessment of the building.

[0113] Embodiment 2:

[0114] like Figure 4 As shown, this embodiment provides a historical and cultural building data monitoring and safety assessment system, the system comprising:

[0115] The excitation module is used to load white noise excitation of different levels to the excitation points of multiple structures of the target building, and obtain the excitation response of each structure, each level corresponding to an acceleration amplitude.

[0116] The response calculation module is used to calculate the safety evaluation value of each structure at each level based on the multiple excitation responses of each structure.

[0117] The fitting module is used to fit the preset functional formula according to all the safety evaluation values ​​of each structure to obtain the fitting functional formula corresponding to each structure.

[0118] The fitting function calculation module is used to calculate the target safety evaluation index of each structure under a preset earthquake level according to the fitting function.

[0119] The analysis module is used to analyze the target safety evaluation index of each structure to obtain the evaluation result of the target building.

[0120] In some specific embodiments, the excitation response includes acceleration response data of three monitoring points, the excitation point and all the monitoring points are on a straight line, and the response calculation module includes:

[0121] The preprocessing module is used to preprocess the stimulus response of a level and the preset stimulus data corresponding to the level to obtain preprocessed data.

[0122] The function module is used to calculate the frequency response function, coherence function and cross-correlation function corresponding to each monitoring point in sequence according to the pre-processed data.

[0123] The frequency response calculation module is used to calculate the frequency response consistency based on the frequency response function differences between adjacent monitoring points.

[0124] The vibration calculation module is used to calculate the vibration correlation degree based on the amplitude change of the coherence function corresponding to each monitoring point.

[0125] The amplitude calculation module is used to calculate the instantaneous amplitude change degree based on the amplitude change of the cross-correlation function corresponding to each monitoring point.

[0126] The comprehensive calculation module is used to calculate the frequency response consistency degree, the vibration consistency degree and the instantaneous consistency degree based on the fuzzy comprehensive evaluation method to obtain a safety evaluation value.

[0127] In some specific embodiments, the vibration calculation module includes:

[0128] The first mean value calculation module is used to calculate a first amplitude mean value according to the amplitude of each coherence function in the time domain.

[0129] The first function calculation module is used to calculate the vibration correlation degree based on the amplitude mean value corresponding to each monitoring point and a first preset formula.

[0130] In some specific embodiments, the amplitude calculation module includes:

[0131] The second mean value calculation module is used to calculate a second amplitude mean value according to the amplitude of each cross-correlation function in the time domain.

[0132] The second function calculation module is used to calculate the instantaneous amplitude change degree based on the amplitude mean corresponding to each monitoring point and the second preset formula.

[0133] In some specific embodiments, the analysis module includes:

[0134] The indicator calculation module is used to solve the preset Weibull distribution according to all the target safety evaluation indicators to obtain the performance indicator.

[0135] A trusted computing module is used to calculate an evaluation value of the target building within a trusted interval based on the performance index and all the target safety evaluation indexes.

[0136] An evaluation module is used to determine an evaluation result of the target building based on the evaluation value.

[0137] It should be noted that, regarding the system in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method, and will not be elaborated here.

[0138] It should be noted that the sequence of the above embodiments of the present invention is only for description and does not represent the advantages and disadvantages of the embodiments. The processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0139] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

Claims

1. A method for monitoring and safety assessment of historical and cultural building data, characterized in that: The method comprises: Applying white noise excitation loading of different levels to excitation points of multiple structures of a target building, and obtaining an excitation response of each structure, wherein each level corresponds to an acceleration amplitude; Calculate the safety evaluation value of each structure at each level based on the multiple stimulus responses of each structure; According to all the safety evaluation values ​​of each structure, a preset function formula is fitted to obtain a fitting function formula corresponding to each structure; The default function is: Among them, P n,p represents the safety evaluation value of the nth structure at the level of acceleration amplitude p; a, b, c and d represent the parameters to be fitted; p represents the acceleration amplitude; Calculate the target safety evaluation index of each structure under a preset earthquake level according to the fitting function; Obtaining an evaluation result of the target building according to the target safety evaluation index analysis of each structure; The excitation response includes acceleration response data of three monitoring points, the excitation point and all the monitoring points are on a straight line, and the safety evaluation value of each structure at each level is calculated based on multiple excitation responses of each structure, including: Preprocessing the stimulus response of a level and the preset stimulus data corresponding to the level to obtain preprocessed data; The frequency response function, coherence function and cross-correlation function corresponding to each monitoring point are calculated in sequence according to the pre-processed data; The frequency response consistency degree is calculated based on the frequency response function difference between adjacent monitoring points; Calculating the vibration correlation degree based on the amplitude change of the coherence function corresponding to each of the monitoring points; Calculating the instantaneous amplitude change degree based on the amplitude change of the cross-correlation function corresponding to each monitoring point; The frequency response consistency degree, vibration consistency degree and instantaneous consistency degree are calculated based on the fuzzy comprehensive evaluation method to obtain a safety evaluation value; The formula for calculating the safety evaluation value based on the fuzzy comprehensive evaluation method is as follows: Among them, P n,p represents the safety evaluation value of the nth structure at the level of acceleration amplitude p; f n,p Indicates the frequency response consistency of the nth structure at the level of acceleration amplitude p; z n,p represents the vibration correlation degree of the nth structure at the level of acceleration amplitude p; e n,p Indicates the instantaneous amplitude change of the nth structure at the level of acceleration amplitude p.

2. The method for monitoring and safety assessment of historical and cultural building data according to claim 1 is characterized in that: The vibration correlation degree is calculated based on the amplitude change of the coherence function corresponding to each monitoring point, including: Calculating a first amplitude mean value according to the amplitude of each coherence function in the time domain; The vibration correlation degree is calculated based on the amplitude mean value corresponding to each monitoring point and the first preset formula.

3. The method for monitoring and safety assessment of historical and cultural building data according to claim 1 is characterized in that: The instantaneous amplitude change degree is calculated based on the amplitude change of the cross-correlation function corresponding to each monitoring point, including: Calculate a second amplitude mean value according to the amplitude of each cross-correlation function in the time domain; The instantaneous amplitude change degree is calculated based on the amplitude mean corresponding to each monitoring point and the second preset formula.

4. The method for monitoring and safety assessment of historical and cultural building data according to claim 1 is characterized in that: The evaluation results of the target building are obtained according to the target safety evaluation index analysis of each structure, including: Solving the preset Weibull distribution according to all the target safety evaluation indicators to obtain performance indicators; Calculate the evaluation value of the target building within a credible interval based on the performance index and all the target safety evaluation indexes; An evaluation result of the target building is obtained based on the evaluation value.

5. A historical and cultural building data monitoring and safety assessment system, characterized in that: include: An excitation module, used to load white noise excitation of different levels to the excitation points of multiple structures of the target building, and obtain the excitation response of each structure, each level corresponding to an acceleration amplitude; A response calculation module, used for calculating the safety evaluation value of each structure at each level based on multiple excitation responses of each structure; A fitting module, used for fitting a preset functional formula according to all the safety evaluation values ​​of each structure to obtain a fitting functional formula corresponding to each structure; The default function is: Among them, P n,p represents the safety evaluation value of the nth structure at the level of acceleration amplitude p; a, b, c and d represent the parameters to be fitted; p represents the acceleration amplitude; A fitting function calculation module, used to calculate the target safety evaluation index of each structure under a preset earthquake level according to the fitting function formula; An analysis module, used to analyze the target safety evaluation index of each structure to obtain the evaluation result of the target building; Wherein, the excitation response includes acceleration response data of three monitoring points, the excitation point and all the monitoring points are on a straight line, and the response calculation module includes: A preprocessing module, used for preprocessing the stimulus response of a level and the preset stimulus data corresponding to the level to obtain preprocessed data; A function module, used to calculate the frequency response function, coherence function and cross-correlation function corresponding to each monitoring point in sequence according to the pre-processed data; A frequency response calculation module, used to calculate the frequency response consistency based on the frequency response function differences between adjacent monitoring points; A vibration calculation module, used for calculating the vibration correlation degree based on the amplitude change of the coherence function corresponding to each of the monitoring points; An amplitude calculation module, used to calculate the instantaneous amplitude change degree based on the amplitude change of the cross-correlation function corresponding to each monitoring point; A comprehensive calculation module, used for calculating the frequency response consistency degree, the vibration consistency degree and the instantaneous consistency degree based on a fuzzy comprehensive evaluation method to obtain a safety evaluation value; The formula for calculating the safety evaluation value based on the fuzzy comprehensive evaluation method is as follows: Among them, P n,p represents the safety evaluation value of the nth structure at the level of acceleration amplitude p; f n,p Indicates the frequency response consistency of the nth structure at the level of acceleration amplitude p; z n,p represents the vibration correlation degree of the nth structure at the level of acceleration amplitude p; e n,p Indicates the instantaneous amplitude change of the nth structure at the level of acceleration amplitude p.

6. The historical and cultural building data monitoring and safety assessment system according to claim 5 is characterized in that: The vibration calculation module comprises: A first mean value calculation module, used for calculating a first amplitude mean value according to the amplitude of each coherence function in the time domain; The first function calculation module is used to calculate the vibration correlation degree based on the amplitude mean value corresponding to each monitoring point and a first preset formula.

7. The historical and cultural building data monitoring and safety assessment system according to claim 5 is characterized in that: The amplitude calculation module comprises: A second mean value calculation module, used for calculating a second amplitude mean value according to the amplitude of each cross-correlation function in the time domain; The second function calculation module is used to calculate the instantaneous amplitude change degree based on the amplitude mean corresponding to each monitoring point and the second preset formula.

8. The historical and cultural building data monitoring and safety assessment system according to claim 5 is characterized in that: The analysis module comprises: An indicator calculation module, used to solve the preset Weibull distribution according to all the target safety evaluation indicators to obtain performance indicators; A trusted computing module, used to calculate an evaluation value of the target building within a trusted interval based on the performance index and all the target safety evaluation indexes; An evaluation module is used to determine an evaluation result of the target building based on the evaluation value.

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