Intelligent acquisition system and method for structural crack data under dynamic load

Abstract

The application discloses a kind of intelligent acquisition system and method of structural crack data under dynamic load, utilize the main control module trigger crack width acquisition module start to carry out duration high-frequency acquisition work and carry out single acquisition work of given time interval, crack width acquisition module is controlled under the main control module in duration to the width of the crack monitored high-frequency acquisition, obtain first type crack width data;And only one crack width data is collected each time, obtain second type crack width data;The intelligent analysis module compares and analyzes first type crack width data, obtains the maximum of first type crack width data of day and corresponding acceleration peak value;Second type crack width data is compared and analyzed, obtains the minimum of second type crack width data of day, is sent to background processing module.Compared with prior art, the application realizes the intelligent acquisition of structure crack data with high efficiency and low cost.

Description

Technical Field

[0001] This invention relates to the fields of intelligent data acquisition and computer technology, and in particular to an intelligent acquisition system and method for structural crack data. Background Technology

[0002] When monitoring existing structures, the development and changes of existing stress cracks are frequently observed. For structures subjected to dynamic loads, the cyclical process of crack opening and closing is closely related to the dynamic load. To capture the maximum crack opening value, current technology uses high-frequency (5–20 Hz or higher) data acquisition via displacement extensometers installed across the cracks. This means obtaining more than five data points per second (including the nominal maximum value). However, this approach has drawbacks: the acquisition device needs to operate continuously, resulting in high energy consumption and requiring a large current for continuous power supply (connected to mains power or solar panels), which has limitations and is costly. Furthermore, the massive amounts of data acquired at the front end require significant transmission and storage, making it inefficient in terms of cost-effectiveness. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention proposes an intelligent acquisition system and method for structural crack data under dynamic loads. Through intelligent analysis, it achieves intelligent acquisition of structural (e.g., bridge structure) crack data under the condition of meeting the triggering criteria.

[0004] This invention is achieved using the following technical solution:

[0005] An intelligent data acquisition system for structural cracks under dynamic loads is disclosed. The system includes a main control module, a crack width acquisition module, an intelligent analysis module, a data transmission module, a power supply module, and a background processing module. The acquisition module, the intelligent analysis module, the data transmission module, and the power supply module are respectively connected to the main control module. The background processing module is remotely connected to the main control module via a wireless network.

[0006] The main control module is connected to the vibration acceleration sensor and is used for the overall control of the intelligent acquisition system. It also senses the vibration acceleration of the structure caused by dynamic load through the vibration acceleration sensor, and triggers the crack width acquisition module to start high-frequency acquisition for a certain duration and single acquisition at a predetermined time interval based on the threshold value of the acquired vibration acceleration.

[0007] The crack width acquisition module is connected to an extensometer. Under the control of the main control module, it performs high-frequency acquisition of the width of the monitored crack over a continuous period of time to obtain several values ​​of the crack width of the structure monitored under the current dynamic load, thus obtaining the first type of crack width data. Also, under the control of the main control module, it performs a limited number of measurements at predetermined time intervals, with each measurement acquiring only one crack width data, thus obtaining the second type of crack width data.

[0008] Under the control of the main control module, the intelligent analysis module compares and analyzes the first type of crack width data obtained by the aforementioned crack width acquisition module to obtain the maximum crack width value at a certain time. It then compares this value with other similar data of the same day to obtain the maximum value of the first type of crack width data and the corresponding peak acceleration value of the day. The intelligent analysis module also compares and analyzes the aforementioned second type of crack width data to obtain the minimum crack width value at a certain time. By comparing this value with other similar data of the same day, it obtains the minimum value of the second type of crack width data of the day.

[0009] The data sending module is used to remotely send the data of the number of continuous acquisition starts, continuous acquisition time, maximum vibration acceleration, maximum width of the first type of crack, and minimum width of the second type of crack to the background processing module.

[0010] The power supply module is used to supply power to the intelligent data acquisition system;

[0011] The background processing module is used to save the maximum vibration acceleration value of the day, as well as data including the maximum value of the crack width of the structure under dynamic load (i.e., the first type of crack width) and the normal value of the crack width under no-load conditions (i.e., the second type of crack width), and to process and display the data.

[0012] A smart method for acquiring structural crack data under dynamic loads, the method being controlled and executed by a main control module, specifically including the following process:

[0013] Step S1: Obtain the external dynamic loads acting on the structure;

[0014] Step S2: The main control module controls the vibration acceleration sensor to sense the vibration acceleration of the external dynamic load;

[0015] Step S3: When the vibration acceleration amplitude acquired in the previous steps exceeds the set threshold a, the crack width acquisition module is triggered to start high-frequency acquisition until the set time is reached or the acceleration amplitude is less than the preset threshold a, then acquisition stops. The first type of crack width data is obtained by high-frequency acquisition. When the vibration acceleration amplitude acquired in the previous steps is lower than the set threshold b, the crack width acquisition module is triggered to start single acquisition at predetermined time intervals, obtaining a limited number of width measurement data. The second type of crack width data is obtained by single acquisition.

[0016] Step S4: The intelligent analysis module compares and analyzes the first type of crack width data obtained in the previous steps to obtain the maximum crack width value for a certain time. It compares the maximum value of the first type of crack width data for the day with other similar data for the same day to obtain the maximum value of the first type of crack width data for the day and the corresponding peak acceleration value. It also compares and analyzes the second type of crack width data obtained in the previous steps to obtain the minimum crack width value for a certain time. It compares the minimum value of the second type of crack width data for the day with other similar data for the same day.

[0017] Step S5: If the vibration acceleration amplitude collected in step S2 is lower than threshold a but higher than threshold b, then no action is taken.

[0018] Step S6: The data sending module remotely sends the number of continuous acquisition starts, continuous acquisition time, maximum vibration acceleration, and data including the maximum crack width of the structure under dynamic load and the minimum crack width under no-load conditions to the background processing module for the day; finally, only the maximum vibration acceleration and the data including the maximum crack width of the structure under dynamic load and the minimum crack width under no-load conditions are saved, and the rest of the data are not retained.

[0019] Compared with existing technologies, this invention achieves intelligent acquisition of structural crack data with high efficiency and low cost, and can balance the contradiction between the acquisition and storage of crack data of existing structures and energy consumption and massive data storage. Attached Figure Description

[0020] Figure 1 This is a module diagram of an intelligent acquisition system for structural crack data under dynamic load according to the present invention;

[0021] Figure 2 This is a flowchart of an intelligent acquisition method for structural crack data under dynamic load according to the present invention. Detailed Implementation

[0022] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings.

[0023] like Figure 1 The diagram shown is a block diagram of an intelligent data acquisition system for structural cracks under dynamic loads according to the present invention. The system includes a main control module 10 and a background processing module 20. The intelligent analysis module 100, the trigger acquisition module 200, the data transmission module 300, and the power supply module 400 are respectively connected to the main control module 10. The main control module 10 is remotely connected to the background processing module 20 via a wireless network.

[0024] The main control module 10 is further connected to the crack width acquisition module 100, the intelligent analysis module 200, the data transmission module 300, and the power supply module 400, and is remotely connected to the background processing module 500 via a wireless network.

[0025] The main control module 10 is used for the overall control of the intelligent acquisition system and to collect vibration acceleration caused by dynamic load from the vibration acceleration sensor 101. When the collected vibration acceleration value exceeds a preset threshold a, the crack width acquisition module is triggered to start high-frequency acquisition until the preset time is reached or the acceleration value is less than the preset threshold a (the latter shall prevail). The acquisition stops when the high-frequency acquisition is reached. The data obtained in this high-frequency acquisition is called the first type of crack width data, which corresponds to the working condition under a large load. Another function of the main control module is to trigger the crack width acquisition module to start single acquisition at a predetermined time interval when the collected acceleration value is lower than the preset threshold b, so as to obtain a limited number of width measurement data (called the second type of crack width data, which corresponds to the no-load condition, i.e., the residual crack width).

[0026] The crack width acquisition module 100 is connected to the extensometer 102. Based on the analysis results, the extensometer 102 is triggered to perform high-frequency acquisition to obtain the maximum crack width of the structure under the dynamic load of the day.

[0027] Under the control of the main control module 500, the intelligent analysis module 200 compares and analyzes the first type of crack width data obtained by the aforementioned crack width acquisition module to obtain the maximum crack width value for a certain time. By comparing it with other similar data on the same day, the maximum value of the first type of crack width data and the corresponding peak acceleration value for the day can be obtained. By comparing and analyzing the aforementioned second type of crack width data, the minimum crack width value for a certain time can be obtained. By comparing it with other similar data on the same day, the minimum value of the second type of crack width data for the day can be obtained.

[0028] Specifically, the extensometer 102 is installed across the crack at a predetermined crack location in the structure, and the displacement extensometer is installed across the crack to achieve high-frequency (5-20Hz or higher) data acquisition.

[0029] The data transmission module 300 is used to remotely transmit data including the number of continuous acquisition starts, continuous acquisition time, maximum vibration acceleration, and the maximum crack width of the structure under dynamic load and the normal crack width under no-load conditions to the background processing module.

[0030] The power supply module 400 is used to power the intelligent acquisition system to ensure its normal operation; it can periodically provide the remaining power status to the remote transmission module and send it to the background processing module 500.

[0031] The background processing module 500 is remotely connected to the main control module 10 via a network. It is used to save the maximum vibration acceleration value of the day, as well as data including the maximum crack width of the structure under dynamic load and the conventional crack width under no-load conditions. Other data is not retained. The module is used for data processing and display.

[0032] The intelligent data acquisition system and method of this invention are mainly aimed at bridges (or similar structures), which are subjected to dynamic loads primarily from vehicles. Under the action of these dynamic loads, data on the width of cracks in the first type of structure is generated and collected. When there is no external load, data on the width of cracks in the second type of structure is generated and collected. For a given location (crack), the influence of vehicle loads peaks from far to near and then gradually recedes into the distance.

[0033] like Figure 2 The diagram shown is an overall flowchart of an intelligent data acquisition method for structural cracks under dynamic loads according to the present invention. The specific steps are described below:

[0034] Step S1: Obtain the frequently occurring external dynamic loads borne by the structure (e.g., bridge);

[0035] Step S2: The main control module controls the vibration acceleration sensor to sense the vibration acceleration of the external dynamic load;

[0036] Step S3: When the acceleration value collected in the previous steps exceeds the preset threshold a, the crack width acquisition module is triggered to start high-frequency acquisition until the preset time is reached or the acceleration value is less than the preset threshold a (the latter shall prevail), at which point acquisition stops (the data obtained in this high-frequency acquisition is called the first type of crack width data); when the acceleration value collected in the previous steps is lower than the preset threshold b, the crack width acquisition module is triggered to start single acquisition at predetermined time intervals, obtaining a finite number of width measurement data (called the second type of crack width data);

[0037] Step S4: The intelligent analysis module compares and analyzes the first type of crack width data obtained in the previous steps to obtain the maximum crack width value. By comparing it with other similar data on the same day, the maximum value of the first type of crack width data and the corresponding peak acceleration value on the same day can be obtained. The intelligent analysis module compares and analyzes the second type of crack width data obtained in the previous steps to obtain the minimum crack width value. By comparing it with other similar data on the same day, the minimum value of the second type of crack width data on the same day can be obtained.

[0038] Step S5: If the acceleration value collected in step S2 is lower than threshold a but higher than threshold b, then no action is taken.

[0039] Step S6: The data sending module remotely sends the daily continuous acquisition start count, continuous acquisition time, maximum vibration acceleration, and data including the maximum crack width of the structure under dynamic load and the minimum crack width under no-load conditions to the background processing module. Ultimately, only the maximum vibration acceleration and the data including the maximum crack width of the structure under dynamic load and the minimum crack width under no-load conditions are saved; all other data are discarded. The discarded data is recorded to allow for gradual adjustment of the acquisition trigger threshold later.

[0040] The crack width under no-load conditions is typically measured using data collected at fixed time intervals (e.g., every 15 minutes) at night.

[0041] Therefore, this invention can obtain the maximum crack width and maximum vibration acceleration of a structure under dynamic load on a given day. The backend data integration platform only needs to store this limited data for an extended period to perform long-term trend analysis of the structure.

Claims

1. An intelligent data acquisition system for structural cracks under dynamic loads, characterized in that, The system includes a main control module, a crack width acquisition module, an intelligent analysis module, a data transmission module, a power supply module, and a backend processing module. The crack width acquisition module, the intelligent analysis module, the data transmission module, and the power supply module are all connected to the main control module. The backend processing module is remotely connected to the main control module via a wireless network. The main control module is connected to a vibration acceleration sensor for overall control of the intelligent acquisition system. It senses the vibration acceleration of the structure caused by dynamic loads through the sensor. The system triggers the crack width acquisition module to begin high-frequency acquisition for a set duration and single acquisitions at predetermined time intervals based on the acquired vibration acceleration value threshold. The main control module triggers the crack width acquisition module to begin high-frequency acquisition when the acquired acceleration value exceeds a pre-set threshold 'a', continuing until the set duration is reached or the acceleration value falls below the pre-set threshold 'a', at which point acquisition stops. Conversely, the main control module triggers the crack width acquisition module to begin single acquisitions at predetermined time intervals when the acquired vibration acceleration value falls below a pre-set threshold 'b', thus obtaining a finite number of width measurement data points. The crack width acquisition module is connected to an extensometer. Under the control of the main control module, it performs high-frequency acquisition of the width of the monitored crack over a continuous period of time to obtain several values ​​of the crack width of the structure monitored under the current dynamic load, thus obtaining the first type of crack width data. Also, under the control of the main control module, it performs a limited number of measurements at predetermined time intervals, with each measurement acquiring only one crack width data, thus obtaining the second type of crack width data. Under the control of the main control module, the intelligent analysis module compares and analyzes the first type of crack width data obtained by the aforementioned crack width acquisition module to obtain the maximum crack width value at a certain time. It then compares this value with other similar data of the same day to obtain the maximum value of the first type of crack width data and the corresponding peak acceleration value of the day. The intelligent analysis module also compares and analyzes the aforementioned second type of crack width data to obtain the minimum crack width value at a certain time. By comparing this value with other similar data of the same day, it obtains the minimum value of the second type of crack width data of the day. The data sending module is used to remotely send the data of the number of continuous acquisition starts, continuous acquisition time, maximum vibration acceleration, maximum width of the first type of crack, and minimum width of the second type of crack to the background processing module. The power supply module is used to supply power to the intelligent data acquisition system; The background processing module is used to save the maximum vibration acceleration value of the day, as well as data including the maximum value of the crack width of the structure under dynamic load (i.e., the first type of crack width) and the normal value of the crack width under no-load conditions (i.e., the second type of crack width), and to process and display the data.

2. The intelligent acquisition system for structural crack data under dynamic load as described in claim 1, characterized in that, The dynamic load includes vehicle load, and the dynamic load generates and collects data on the crack width of the first type of structure.

3. The intelligent acquisition system for structural crack data under dynamic load as described in claim 1, characterized in that, The extensometer is installed across the crack at a predetermined crack location in the structure to achieve high-frequency data acquisition.

4. A method for intelligently acquiring structural crack data under dynamic load, characterized in that, This method is implemented by the system of any one of claims 1 to 3, and the method includes the following specific steps: Step S1: Obtain the external dynamic loads acting on the structure; Step S2: The main control module controls the vibration acceleration sensor to sense the vibration acceleration of the external dynamic load; Step S3: When the vibration acceleration amplitude collected in the previous steps exceeds the set threshold a, the crack width acquisition module is triggered to start high-frequency acquisition until the set time is reached or the acceleration amplitude is less than the preset threshold a, and then the acquisition stops. The first type of crack width data is obtained by high-frequency acquisition. When the vibration acceleration amplitude acquired in the aforementioned steps is lower than the set threshold b, the crack width acquisition module is triggered to start a single acquisition operation at a predetermined time interval, obtaining a finite number of width measurement data, and the second type of crack width data is obtained from the single acquisition. Step S4: The intelligent analysis module compares and analyzes the first type of crack width data obtained in the previous steps to obtain the maximum crack width value for a certain time. It compares the maximum value of the first type of crack width data for the day with other similar data for the same day to obtain the maximum value of the first type of crack width data for the day and the corresponding peak acceleration value. It also compares and analyzes the second type of crack width data obtained in the previous steps to obtain the minimum crack width value for a certain time. It compares the minimum value of the second type of crack width data for the day with other similar data for the same day. Step S5: If the vibration acceleration amplitude collected in step S2 is lower than threshold a but higher than threshold b, then no action is taken. Step S6: The data sending module remotely sends the number of continuous acquisition starts, continuous acquisition time, maximum vibration acceleration, and data including the maximum crack width of the structure under dynamic load and the minimum crack width under no-load conditions to the background processing module for the day; finally, only the maximum vibration acceleration and the data including the maximum crack width of the structure under dynamic load and the minimum crack width under no-load conditions are saved, and the rest of the data are not retained.

Images