Ancient building safety monitoring system based on BIM technology

Abstract

The invention discloses an ancient building safety monitoring system based on a BIM (Building Information Modeling) technology, relates to the technical field of ancient buildings, and solves the problems that safety monitoring is insufficient in comprehensiveness, and safety node hidden dangers existing in an ancient building cannot be confirmed in real time. Determining a trend characteristic interval and comparing the trend characteristic interval with a preset interval in a database so as to clearly judge an abnormal reason and display a corresponding abnormal signal; therefore, powerful support is provided for safety management and control of the historic building, maintenance personnel can take targeted measures in time according to the information, the risk that the historic building is damaged due to abnormal structural stress is reduced, the efficiency and scientificity of safety monitoring of the historic building are greatly improved, and long-term protection and sustainable development of the historic building are facilitated.

Description

Technical Field

[0001] The present invention relates to the technical field of ancient architecture, and specifically to an ancient architecture safety monitoring system based on BIM technology. Background Art

[0002] Ancient architectures carry rich historical and cultural information. Their spatial forms not only reflect the architectural techniques of that time but also contain various connotations in aspects such as society and culture. Accurately identifying the spatial forms of ancient architectures is of great significance for the protection, repair, and historical and cultural research of ancient architectures. Traditional research methods for the spatial forms of ancient architectures mostly rely on manual on-site measurement and recording, with low efficiency and large influence of human factors on accuracy. With the development of computer vision technology, image-based recognition methods provide a new approach for the research of the spatial forms of ancient architectures. By collecting, processing, and analyzing ancient architecture images, the spatial form information of ancient architectures can be obtained quickly and accurately, providing strong support for the protection and research of ancient architectures.

[0003] The application with the publication number CN111741094A discloses an ancient architecture environmental protection system based on wireless sensors, including a management terminal. The remote monitoring terminal and the warning terminal are connected to the management terminal through an external network. The remote management terminal. The management terminal uses a computer to receive the data information of the ancient architecture monitored by the remote monitoring terminal through a wireless network transmission method and stores the received data information in a database. Each sensor detects and monitors the data of the wire in this working state. The alarm is used to alarm and remind when the data exceeds the safety valve value, reminding the maintenance personnel to carry out maintenance. The positioning sensor is used to locate the quantity and position of the junction boxes installed on the ancient architecture, facilitating the maintenance personnel to repair the joints of two adjacent wires connected through the junction box. The fire caused by the short-circuited wire is likely to cause damage to the ancient architecture, and then lead to the destruction of the ancient architecture environment.

[0004] During the safety monitoring process of ancient architectures, generally, based on the collected relevant parameters, it is used to evaluate whether there are potential safety hazards in the corresponding building environment. However, the original such safety hazard monitoring method can only monitor the external specific environment, and the relevant data of the internal building nodes cannot be monitored. The comprehensiveness of safety monitoring is insufficient, and it cannot confirm the potential safety node hazards in the ancient architecture in real time. Summary of the Invention

[0005] Aiming at the deficiencies of the prior art, the present invention provides an ancient architecture safety monitoring system based on BIM technology, which solves the problems of insufficient comprehensiveness of safety monitoring and inability to confirm the potential safety node hazards in the ancient architecture in real time.

[0006] To achieve the above object, the present invention is implemented through the following technical solutions: An ancient building safety monitoring system based on BIM technology, including:

[0007] A BIM model analysis terminal, based on the associated model values at the node positions in the BIM model, to confirm the axial force, bending moment force, and shear force associated with the corresponding model node. The specific method is as follows:

[0008] Confirm the axial pressure N associated with the model node from the BIM model i , where i represents different model nodes in this BIM model, and then confirm the cross-sectional area M associated with the stress surface of the corresponding model node i ;

[0009] Adopt Z i =N i ÷M i To confirm the axial force Z of the model node i ;

[0010] The specific method for confirming the bending moment force of the model node is: Confirm the bending moment W transmitted from the beam end associated with this model node to this node i , the moment of inertia G of the beam section i , the distance L from the model node to the neutral axis of the beam i , adopt WJ i =(W i ×L i )÷G i To lock the bending moment force WJ regarding this model node i ;

[0011] The specific method for confirming the shear force of the model node is: Directly confirm the shear force O transmitted from the associated beam end to this node from the BIM model i , and then confirm the cross-sectional area A of the corresponding associated beam end i , adopt JY i =O i ÷A i To confirm the shear force JY associated with the corresponding model node i ;

[0012] A stress data confirmation terminal, based on the axial force, bending moment force, and shear force associated with different model nodes in the BIM model, to confirm the comprehensive stress associated with the corresponding model node. The specific method is as follows:

[0013] Based on the axial force Z, bending moment force WJ, and shear force JY associated with the corresponding model node i , bending moment force WJ i , and shear force JY i , first based on the associated axial force Z i , bending moment force WJ i Lock the superimposed force associated with the corresponding model node, where the superimposed force = Zi +WJ i Calibrate the confirmed superimposed force as D i ;

[0014] Then adopt: Confirm the comprehensive stress, where ± represents two treatment methods, confirm two groups of comprehensive stresses, calibrate the comprehensive stress confirmed by the "+" value treatment method in "±" as the first comprehensive stress, and calibrate the comprehensive stress confirmed by the "-" value treatment method in "±" as the second comprehensive stress;

[0015] At the node data verification end, check the error between the comprehensive stress confirmed by the corresponding model node and the monitoring data associated with the strain gauge, identify and confirm the difference between the comprehensive stress of the model node and the detection data of the strain gauge, and lock the abnormal node based on whether the identified difference meets the standard. The specific method is:

[0016] Calibrate the first comprehensive stress confirmed by the corresponding model node as ZH1 i Calibrate the second comprehensive stress as ZH2 i Then calibrate the monitoring data associated with the strain gauge as YB i ;

[0017] Prioritize identifying the difference between the second comprehensive stress ZH2 i and YB i to see if it meets: |ZH2 i - YB i | ≤ Y1, where Y1 is a preset value:

[0018] If it meets, then further identify whether the difference between the first comprehensive stress calibrated as ZH1 i and YB i meets: |ZH1 i - YB i | ≤ Y1. If it meets, it means the numerical difference meets the standard. If not, calibrate the node where this strain gauge is located as an abnormal node;

[0019] If not, directly calibrate the node where this strain gauge is located as an abnormal node;

[0020] And transmit the calibrated abnormal node to the historical data analysis end;

[0021] At the historical data analysis end, extract the historical data of the abnormal node, confirm the strain change trend of this abnormal node from it, then conduct a verification analysis on the confirmed strain change trend, determine the trend characteristic interval, compare the determined trend characteristic interval with the preset interval in the database, and confirm and display the comparison signal based on the comparison result. The specific method is:

[0022] Based on the current moment, a set of traceability periods are confirmed, and the traceability period is a preset period. Based on the monitoring data of different strain gauges associated with different moments within the traceability period, a strain gauge monitoring curve belonging to this abnormal node is generated;

[0023] From the generated strain gauge monitoring curve, identify the change trend between adjacent moment nodes. Calibrate the strain gauge monitoring data associated with adjacent moment nodes as YB1 and YB2, where YB1 is the previous set of strain gauge monitoring data and YB2 is the next set of strain gauge monitoring data. Use: change trend = (YB2 - YB1) ÷ time interval to lock the change trend between adjacent moment nodes. The time interval is the time difference between adjacent moment nodes. Calibrate the change trends between different adjacent moment nodes as BH k , where k represents different adjacent moment node curve segments;

[0024] From the confirmed several groups of change trends BH k Lock the trend characteristic interval: Select the minimum value and the maximum value from several groups of change trends BH k Based on the minimum value and the maximum value, confirm a variable interval, and adjust the endpoint values of the variable interval. The adjusted interval endpoint values shall not exceed the confirmed minimum value and maximum value. Execute several adjustment processes, and the variable intervals associated with each adjustment process are different;

[0025] For each different adjustment process, identify the numerical range Fq of the corresponding variable interval, where q represents different variable intervals, and then confirm the total number Zq of change trends BH k included in the corresponding variable interval. Use: Mq = Zq ÷ Fq to confirm the interval characteristic Mq associated with the corresponding variable interval. From the interval characteristics Mq associated with different variable intervals, select the variable interval associated with Mqmax as the trend characteristic interval associated with this adjustment process.

[0026] Preferably, the specific method for the historical data analysis terminal to compare the determined trend characteristic interval with the preset interval in the database is as follows:

[0027] According to the trend characteristic interval confirmed for the abnormal node, check this trend characteristic interval with the preset intervals existing in the database. The database stores three groups of preset intervals, and the endpoint values of the preset intervals are all preset values. Each group of preset intervals is different. The three groups of preset intervals are: axial force abnormal interval, bending moment abnormal interval, and shear force abnormal interval;

[0028] Identify the overlapping range between this trend feature interval and its preset interval, and determine the comprehensive occupancy ratio of the overlapping range in the trend feature interval and the preset interval. Use: overlapping range ÷ trend feature interval = the first occupancy ratio, and then use: overlapping range ÷ preset interval = the second occupancy ratio. Perform a mean value process on the first occupancy ratio and the second occupancy ratio to confirm the comprehensive occupancy ratio, and identify whether the comprehensive occupancy ratio meets: comprehensive occupancy ratio ≥ 70%. If it meets, label this preset interval as the signal output interval. If there is no preset interval that meets this condition, directly generate an error signal for display;

[0029] If the signal output interval is the axial force abnormal interval, generate an axial force abnormal signal for display;

[0030] If the signal output interval is the bending moment force abnormal interval, generate a bending moment force abnormal signal for display;

[0031] If the signal output interval is the shear force abnormal interval, generate a shear force abnormal signal for display.

[0032] The present invention provides an ancient building safety monitoring system based on BIM technology. Compared with the prior art, it has the following beneficial effects:

[0033] The present invention conducts error checking on the comprehensive stress of model nodes and the monitoring data of strain gauges. Through a rigorous determination process, it can quickly and accurately identify abnormal nodes; this way of closely combining the theoretical model with actual monitoring data effectively guarantees the accuracy of the safety state assessment of ancient building nodes, timely discovers potential safety hazards, and provides a clear direction for the maintenance and repair of ancient buildings;

[0034] By deeply mining the historical data of abnormal nodes, determining the trend feature interval and comparing it with the preset interval in the database, it can clearly judge the cause of the abnormality and display the corresponding abnormal signal; this provides strong support for the safety control of ancient buildings. Maintenance personnel can take targeted measures in a timely manner based on this information to reduce the risk of damage to ancient buildings due to abnormal structural stress, greatly improving the efficiency and scientific nature of ancient building safety monitoring, and contributing to the long-term protection and sustainable development of ancient buildings. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a schematic diagram of the principle framework of the present invention;

[0036] Figure 2 is a schematic diagram for determining abnormal nodes of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0037] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0038] The first embodiment

[0039] Please refer to Figure 1 , this application provides an ancient building safety monitoring system based on BIM technology, including a BIM model analysis terminal, a stress data confirmation terminal, a node data verification terminal, a historical data analysis terminal, and a database. Among them, the BIM model analysis terminal, the stress data confirmation terminal, the node data verification terminal, and the historical data analysis terminal are electrically connected in sequence from the output node to the input node, and the database is electrically connected to the input node of the historical data analysis terminal;

[0040] Among them, for the relevant ancient buildings that need to be monitored for safety, the BIM model analysis terminal presets corresponding BIM models of ancient buildings in advance, conducts force analysis and confirmation on the preset BIM models, and based on the associated model values at the node positions in the BIM models, confirms the axial force, bending moment force, and shear force associated with the corresponding model nodes, and transmits the confirmed axial force, bending moment force, and shear force into the stress data confirmation terminal. The specific method for confirming the axial force of the model node is as follows:

[0041] Confirm the axial pressure N associated with the model node from the BIM model i , where i represents different model nodes in this BIM model, and then confirm the cross-sectional area M associated with the force-bearing surface of the corresponding model node i ;

[0042] Adopt Z i =N i ÷M i To confirm the axial force Z of the model node i , the axial force of a single node is related to the pressure received by the corresponding node and the corresponding cross-sectional area. Based on the pressure and the corresponding cross-sectional area, the axial force associated with the corresponding node can be locked, and the pressure value of the corresponding node can be directly extracted from the corresponding BIM model;

[0043] Among them, the specific method for confirming the bending moment force of the model node is: confirm the bending moment W transmitted from the beam end associated with this model node to this node i , the moment of inertia G of the beam cross-section i , the distance L from the model node to the neutral axis of the beam i , adopt WJ i =(W i ×L i) ÷ G i Lock the bending moment force WJ of this model node i ;

[0044] The specific method to confirm the shear force of the model node is: directly confirm the shear force transferred from the associated beam end to this node within the BIM model O i , then confirm the cross-sectional area A of the corresponding associated beam end i , and adopt JY i = O i ÷ A i Confirm the shear force JY associated with the corresponding model node i ;

[0045] For different characteristic nodes in the model, directly extract the associated node data from the model, and then based on the extracted node data, confirm the relevant forces associated with the corresponding characteristic nodes. The confirmed relevant forces are all the forces associated with the standard values in the model, which can serve as a better standard for facilitating subsequent actual comparison.

[0046] Among them, at the stress data confirmation end, based on the axial force, bending moment force, and shear force associated with different model nodes in the BIM model, confirm the comprehensive stress associated with the corresponding model node (this comprehensive stress is the specific force monitored by the subsequent strain gauge), and transmit the confirmed comprehensive stress to the node data verification end. The specific method to confirm the comprehensive stress is as follows:

[0047] Based on the axial force Z associated with the corresponding model node i , bending moment force WJ i , and shear force JY i , first based on the associated axial force Z i , bending moment force WJ i , lock the superimposed force associated with the corresponding model node. The superposition of the normal stresses generated by the axial force and the bending moment follows the principle of linear superposition, that is, the forces are added. Among them, the superimposed force = Z i + WJ i , and calibrate the confirmed superimposed force as D i ;

[0048] Then adopt: Confirm the comprehensive stress, where ± represents two processing methods, and confirm two sets of comprehensive stresses. Calibrate the comprehensive stress confirmed by the “+” value processing method in “±” as the first comprehensive stress (which is the maximum value, and its first comprehensive stress determines the possibility of tensile failure of the material), and calibrate the comprehensive stress confirmed by the “-” value processing method in “±” as the second comprehensive stress (which is the minimum value, and its second comprehensive stress provides a numerical basis for compressive failure analysis). What is determined here is not an interval, but two sets of comprehensive stresses, each with a maximum value and a minimum value;

[0049] The comprehensive stress determined here needs to be transmitted to the node data verification end. The node data verification end conducts a comprehensive analysis based on the stress data detected by the corresponding strain gauges and in combination with the specific comprehensive stress confirmed in this processing process, to determine whether the corresponding comprehensive stress has a consistent error in the numerical verification standard, so as to achieve a better analysis and evaluation effect and ensure the accuracy of the analysis and evaluation.

[0050] Among them, in combination Figure 2 , the node data verification end conducts an error check on the comprehensive stress confirmed by the corresponding model node and the monitoring data associated with the strain gauge, identifies and confirms the difference between the comprehensive stress of the model node and the detection data of the strain gauge, and confirms whether the identified difference meets the standard, and evaluates the abnormal nodes. The specific method of evaluation is as follows:

[0051] Calibrate the first comprehensive stress confirmed by the corresponding model node as ZH1 i , calibrate the second comprehensive stress as ZH2 i , and then calibrate the monitoring data associated with the strain gauge as YB i ;

[0052] First, identify whether the difference between the second comprehensive stress ZH2 i and YB i meets: |ZH2 i -YB i |≤Y1, where Y1 is a preset value, and its specific value is determined by the operator according to experience:

[0053] If it meets, then identify whether the difference between the first comprehensive stress calibrated as ZH1 i and YB i meets: |ZH1 i -YB i |≤Y1. If it meets, it means that the numerical difference meets the standard. If it does not meet, then calibrate the node where this strain gauge is located as an abnormal node;

[0054] If it does not meet, then directly calibrate the node where this strain gauge is located as an abnormal node;

[0055] And transmit the calibrated abnormal nodes to the historical data analysis end.

[0056] Specifically, in the actual monitoring process, if there is a large difference between the monitored data and the standard data actually generated by the corresponding model, it means that there are related numerical abnormalities in the corresponding nodes. If there is no large difference, it means that there are no large related abnormalities in the corresponding nodes and they are in a normal state. Therefore, through the corresponding numerical comparison results, it is possible to lock whether the corresponding nodes are abnormal nodes and conduct a comprehensive evaluation in the subsequent analysis process.

[0057] Second Embodiment

[0058] Among them, the historical data analysis terminal extracts the historical data of the calibrated abnormal nodes, confirms the strain change trend of this abnormal node from the extracted historical data, conducts a verification analysis on the confirmed strain change trend, determines the trend characteristic interval, compares the determined trend characteristic interval with the preset characteristic interval in the database, and confirms and displays the comparison signal based on the comparison result (determines the abnormal cause of the corresponding abnormal node and displays it in real time, which is convenient for the safety control of ancient buildings), and the specific method for determining the trend characteristic interval is as follows:

[0059] Based on the current moment, a set of traceability periods is confirmed. The traceability period is a preset period, which is formulated in advance by relevant personnel according to experience, and the traceability period generally takes a value of 30 days. Based on the monitoring data of different strain gauges associated with different moments within the traceability period, a strain gauge monitoring curve belonging to this abnormal node is generated. The horizontal axis of this curve is the time line, and its vertical axis is the strain gauge monitoring data (i.e., stress). The initial endpoint of this monitoring curve is the initial moment of the traceability period, and its terminal endpoint is the current moment;

[0060] From the generated strain gauge monitoring curve, identify the change trend between adjacent moment nodes. Calibrate the strain gauge monitoring data associated with adjacent moment nodes as YB1 and YB2, where YB1 is the previous set of strain gauge monitoring data and YB2 is the next set of strain gauge monitoring data. Use: change trend = (YB2 - YB1) ÷ time interval to lock the change trend between adjacent moment nodes. The time interval is the time difference between adjacent moment nodes, and label the change trends between different adjacent moment nodes as BH k where k represents different adjacent moment node curve segments;

[0061] From the confirmed several groups of change trends BH k lock the trend characteristic interval: select the minimum value and the maximum value from the several groups of change trends BH k to confirm a variable interval based on the minimum value and the maximum value, and adjust the endpoint values of the variable interval. The adjusted interval endpoint values shall not exceed the confirmed minimum value and maximum value. Execute several adjustment processes, and the variable intervals associated with each adjustment process are different;

[0062] For each different adjustment process, identify the numerical range Fq of the corresponding variable interval, where q represents different variable intervals, and then confirm the change trends BH included in the corresponding variable interval kThe total number Zq is used to confirm the interval feature Mq associated with the corresponding variable interval by: Mq = Zq ÷ Fq. From the interval features Mq associated with different variable intervals, the variable interval associated with Mqmax is selected as the trend feature interval associated with this adjustment process;

[0063] Specifically, if the confirmed minimum value and maximum value are determined to be 1 and 9, then the confirmed variable interval is [1, 9]. Based on this variable interval [1, 9], the relevant confirmation of subsequent variable intervals is carried out. After confirmation, the variable intervals can be adjusted to: [1, 8], [1, 7], …… [1, 2], [2, 9], [2, 8], etc. The variable intervals associated with each different interval range are all different, so the interval features associated with each different variable interval are also different. According to the corresponding interval range and the associated total number, the specific interval features are confirmed. When the interval feature is larger, it means that the density of the corresponding confirmed trend feature interval is higher and its characteristic is stronger. Therefore, the corresponding trend feature interval can be locked.

[0064] Among them, the specific method for comparing the determined trend feature interval with the preset interval in the database is as follows:

[0065] According to the trend feature interval confirmed by the abnormal node, this trend feature interval is checked against the preset intervals existing in the database. There are three groups of preset intervals stored in the database, and the endpoint values of the preset intervals are all preset values. Each group of preset intervals is different. The three groups of preset intervals are: axial force abnormal interval, bending moment force abnormal interval, and shear force abnormal interval;

[0066] Identify the overlapping range between this trend feature interval and its preset interval, and determine the comprehensive occupancy ratio of the overlapping range in the trend feature interval and the preset interval. Use: overlapping range ÷ trend feature interval = the first occupancy ratio, and then use: overlapping range ÷ preset interval = the second occupancy ratio. Perform an averaging process on the first occupancy ratio and the second occupancy ratio to confirm the comprehensive occupancy ratio, and identify whether the comprehensive occupancy ratio meets: comprehensive occupancy ratio ≥ 70%. If it meets, mark this preset interval as the signal output interval. If there is no preset interval that meets this condition, directly generate an error signal for display. When the error signal exists, it means that there are relatively large problems in the actual safety monitoring process, and the maintenance personnel need to carry out maintenance processing in a timely manner. It is necessary to evaluate the relevant problems existing in the building support in combination with the actual situation of the building support;

[0067] If the signal output interval is the axial force abnormal interval, generate an axial force abnormal signal for display;

[0068] If the signal output interval is the bending moment force abnormal interval, generate a bending moment force abnormal signal for display;

[0069] If the signal output interval is the shear force abnormal interval, a shear force abnormal signal is generated for display.

[0070] Some of the data in the above formula are numerically calculated after removing their dimensions, and the content not described in detail in this specification belongs to the prior art well-known to those skilled in the art.

[0071] The above embodiments are only used to illustrate the technical method of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical method of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical method of the present invention.

Claims

1. The ancient building safety monitoring system based on BIM technology is characterized by: include: The BIM model analysis end determines the axial force, bending moment and shear force associated with the corresponding model node based on the associated model values ​​at the node positions in the BIM model; The stress data confirmation end confirms the comprehensive stress associated with the corresponding model node based on the axial force, bending moment and shear force associated with different model nodes in the BIM model; The node data checking end performs error checking on the comprehensive stress confirmed by the corresponding model node and the monitoring data associated with the strain gauge, identifies and confirms the difference between the comprehensive stress of the model node and the strain gauge detection data, and locks the abnormal node based on whether the identified difference meets the standard; On the historical data analysis side, the historical data of the abnormal node is extracted to confirm the strain change trend of the abnormal node, and then the confirmed strain change trend is verified and analyzed to determine the trend characteristic interval. The determined trend characteristic interval is compared with the preset interval in the database, and the comparison signal is confirmed and displayed based on the comparison result.

2. The ancient building safety monitoring system based on BIM technology according to claim 1 is characterized in that: The BIM model analysis end confirms the axial force of the model node in the following specific manner: Confirm the axial pressure N associated with the model node from the BIM model i , where i represents different model nodes in this BIM model, and then confirm the cross-sectional area M associated with the corresponding model node bearing surface i ; Using Z i =N i ÷M i Confirm the model node axial force Z i ; The specific method of confirming the bending moment force of the model node is: confirm the bending moment W transmitted to this node from the end of the beam associated with this model node i , beam section moment of inertia G i , the distance L between the model node and the neutral axis of the beam i , using WJ i =(W i ×L i )÷G i Lock the bending moment WJ about this model node i ; The specific method of confirming the shear force of the model node is: directly confirm the shear force O transmitted to this node from the associated beam end in the BIM model i , and then confirm the cross-sectional area A of the corresponding associated beam end i , using JY i =O i ÷A i Confirm the shear force JY associated with the corresponding model node i .

3. The ancient building safety monitoring system based on BIM technology according to claim 1 is characterized in that: The stress data confirmation terminal confirms the comprehensive stress associated with the model node in the following specific manner: Based on the axial force Z associated with the corresponding model node i , bending moment WJ i And shear force JY i , based primarily on the associated axial force Z i , bending moment WJ i Lock the superposition force associated with the corresponding model node, where superposition force = Z i +WJ i , and the confirmed superposition force is calibrated as D i ; Then use: Confirm the comprehensive stress, where ± represents two processing methods. Confirm two sets of comprehensive stresses. The comprehensive stress confirmed by the "+" value processing method in "±" is calibrated as the first comprehensive stress, and the comprehensive stress confirmed by the "-" value processing method in "±" is calibrated as the second comprehensive stress.

4. The ancient building safety monitoring system based on BIM technology according to claim 1 is characterized in that: The node data checking end evaluates abnormal nodes in the following specific manner: The first comprehensive stress confirmed by the corresponding model node is calibrated as ZH1 i , the second comprehensive stress is calibrated as ZH2 i , and then calibrate the monitoring data associated with the strain gauge as YB i ; Prioritize identification of the second comprehensive stress ZH2 i With YB i Is the difference between: |ZH2 i -YB i |≤Y1, where Y1 is the preset value: If it meets the requirements, the first comprehensive stress is identified and calibrated as ZH1 i With YB i Is the difference between: |ZH1 i -YB i |≤Y1, if it meets the standard, it means that the value difference meets the standard. If it does not meet the standard, the node where the strain gauge is located is marked as an abnormal node; If it does not meet the requirements, the node where the strain gauge is located will be directly marked as an abnormal node; The marked abnormal nodes are transmitted to the historical data analysis terminal.

5. The ancient building safety monitoring system based on BIM technology according to claim 1 is characterized in that: The specific method of determining the trend feature interval at the historical data analysis end is: Based on the current moment, a set of traceability cycles is confirmed, where the traceability cycle is a preset cycle, and based on different strain gauge monitoring data associated with different moments in the traceability cycle, a strain gauge monitoring curve belonging to the abnormal node is generated; From the generated strain gauge monitoring curve, the change trend between adjacent time nodes is identified, and the strain gauge monitoring data associated with the adjacent time nodes are calibrated as YB1 and YB2, where YB1 is the previous set of strain gauge monitoring data, and YB2 is the next set of strain gauge monitoring data. The change trend between adjacent time nodes is locked using: change trend = (YB2-YB1) ÷ time interval, and the time interval is the time difference between adjacent time nodes. The change trend between different adjacent time nodes is calibrated as BH k , where k represents different adjacent time node curve segments; From the confirmed trend of several groups BH k In the trend feature interval, lock the trend feature interval: from several groups of change trends BH k A minimum value and a maximum value are selected, a set of variable intervals are confirmed based on the minimum value and the maximum value, and the endpoint values ​​of the variable intervals are adjusted, and the adjusted interval endpoint values ​​shall not exceed the confirmed minimum value and the maximum value, and several adjustment processes are executed, and the variable intervals associated with each adjustment process are different; For each different adjustment process, identify the value range Fq of the corresponding variable interval, where q represents the different variable intervals, and then confirm the change trend BH included in the corresponding variable interval k The total number Zq is used: Mq=Zq÷Fq to confirm the interval feature Mq associated with the corresponding variable interval. From the interval features Mq associated with different variable intervals, the variable interval associated with Mqmax is selected as the trend feature interval associated with this adjustment process.

6. The ancient building safety monitoring system based on BIM technology according to claim 5 is characterized in that: The specific method of comparing the determined trend feature interval with the preset interval in the database by the historical data analysis end is: According to the trend characteristic interval confirmed by the abnormal node, the trend characteristic interval is checked with the preset interval in the database, wherein the database stores three groups of preset intervals, the endpoint values ​​of the preset intervals are all preset values, and each group of preset intervals is different. The three groups of preset intervals are: axial force abnormal interval, bending moment force abnormal interval and shear force abnormal interval; Identify the overlapping range of this trend feature interval and its preset interval, and determine the comprehensive proportion of the overlapping range between the trend feature interval and the preset interval, using: overlapping range ÷ trend feature interval = first proportion value, and then using: overlapping range ÷ preset interval = second proportion value, average the first proportion value and the second proportion value, confirm the comprehensive proportion value, and identify whether the comprehensive proportion value satisfies: comprehensive proportion value ≥ 70%. If so, mark this preset interval as the signal output interval. If there is no preset interval that meets this condition, directly generate an error signal for display.

7. The ancient building safety monitoring system based on BIM technology according to claim 6 is characterized in that: If the signal output interval is an abnormal axial force interval, an abnormal axial force signal is generated for display; If the signal output interval is an abnormal bending moment force interval, an abnormal bending moment force signal is generated for display; If the signal output interval is a shear force abnormality interval, a shear force abnormality signal is generated for display.

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