A bridge disease diagnosis and evaluation method based on monitoring and sensing technology

Abstract

The present invention belongs to the technical field of bridge disease diagnosis, and specifically discloses a bridge disease diagnosis and evaluation method based on monitoring perception technology, including: by monitoring the structural diseases, material diseases and traffic diseases of the bridge, respectively confirming the structural disease impact index, material disease impact index and traffic load disease impact index of the bridge, and then confirming the disease impact level of the bridge, and providing corresponding feedback; the present invention confirms the structural disease impact index of the bridge according to the structural information of each bridge part, thereby increasing the attention to the deformation of the bridge, ensuring the accuracy of the assessment of the structural diseases of the bridge, and then improving the reliability of the bridge durability assessment, thereby ensuring the timeliness of the prediction of the development trend of the bridge disease, and at the same time, by performing comprehensive bridge disease diagnosis in multiple dimensions according to the structural diseases, material diseases and traffic load diseases of the bridge, thereby ensuring the effectiveness of the bridge disease assessment.

Description

Technical Field

[0001] The present invention belongs to the technical field of bridge disease diagnosis, and relates to a bridge disease diagnosis and evaluation method based on monitoring perception technology. Background Art

[0002] Bridges are key nodes in the transportation network. A large number of vehicles and pedestrians rely on bridges for smooth passage. If bridge defects are not discovered and treated in a timely manner, the performance of the bridge structure will be degraded, and problems such as crack expansion and component deformation will occur, which will in turn cause serious accidents such as partial or even overall collapse, posing a huge threat to the safety of life and property of passing vehicles and pedestrians. Therefore, it is necessary to diagnose and evaluate bridge defects.

[0003] For example, the Chinese invention patent with publication number CN106055813A discloses a bridge disease diagnosis and maintenance decision-making system, which relates to the field of bridge disease inspection and maintenance technology, including a disease input module for inputting the characteristic information of the bridge disease to be tested; a disease information storage module for storing the characteristic information of existing bridge diseases; a disease cause analysis module for comparing the characteristic information of the bridge disease to be tested with the characteristic information of the existing bridge disease stored in the disease information storage module to analyze the possible causes of the disease; and a disease treatment module for providing a maintenance treatment plan and cycle according to the cause of the disease obtained by the disease cause analysis module. The system analyzes and compares the characteristic information of the bridge disease to be tested with the causes of bridge diseases stored in the system, automatically analyzes and selects the most likely causes of bridge diseases, and provides a suitable maintenance treatment plan, without the need for manual analysis of the causes of bridge diseases and providing maintenance treatment plans, thereby reducing manual workload and improving work efficiency.

[0004] For example, the Chinese invention patent with publication number CN105184065A discloses a bridge damage identification method based on normal mean, and the specific identification is divided into eight steps: select the monitoring bridge, perform structural analysis on it, and determine the monitoring items; arrange the monitoring points, including the monitoring point coding, corresponding sensor type, and spatial three-dimensional coordinates; according to the arrangement plan of the monitoring points; collect the stress, deformation, displacement, cable force, and modal data of each monitoring point for more than one year; establish the normal mean model of the corresponding monitoring data of each monitoring point according to the statistical result mean μ and standard deviation σ; in establishing different monitoring data of each monitoring point: according to the location information of each monitoring point and the spatial three-dimensional coordinates, find the damaged structure and the location of the damage, so as to facilitate the bridge maintenance management personnel to carry out maintenance and repair work and ensure the safe operation of the bridge. The present invention provides corresponding judgment conditions for the bridge management unit to diagnose the disease and maintain the bridge, which is of great significance to the development of the bridge health monitoring system.

[0005] The above existing technologies have the following deficiencies: 1. When diagnosing bridge structure defects, the current method mainly compares and analyzes the characteristic information of the bridge defects to be tested with the existing bridge defect characteristic information stored in the defect information storage module, without considering the individual differences between the structural defects of each bridge part, resulting in insufficient accuracy in the assessment of bridge structure defects, and further resulting in insufficient reliability in the assessment of bridge durability, thereby failing to guarantee the timeliness of the prediction of the development trend of bridge defects, and failing to guarantee the accuracy of the judgment of the subsequent development speed of bridge structure defects.

[0006] 2. Currently, the diagnosis of bridge defects is mainly carried out through normal mean calculation of stress, deformation, displacement, cable force and modal data of each monitoring point. In other words, insufficient attention is paid to the diagnosis of bridge traffic defects, which leads to insufficient effectiveness of the overall safety assessment of the bridge, resulting in insufficient comprehensiveness of bridge diagnosis, insufficient pertinence in subsequent bridge maintenance and reinforcement decision-making, and insufficient rationality in the formulation of bridge reinforcement plans. Summary of the invention

[0007] In view of this, in order to solve the problems raised in the above background technology, a bridge disease diagnosis and evaluation method based on monitoring perception technology is proposed.

[0008] The purpose of the present invention can be achieved through the following technical solutions: The present invention provides a bridge disease diagnosis and evaluation method based on monitoring and sensing technology, including: Step 1, bridge structure disease monitoring: monitoring the structural information of each bridge part, including settlement height, lateral displacement, offset angle, number of cracks, length, width and depth of each crack.

[0009] Step 2: Confirmation of bridge structure defects: Confirm the structural defect impact index of the bridge based on the structural information of each bridge part.

[0010] Step 3. Bridge material disease monitoring: monitor the material information and environmental information of the bridge. The material information includes the number of corroded parts of the steel bars, the corrosion area of ​​each corrosion part, the corrosion depth, and the number of detached parts of the concrete, the detached area of ​​each detached part and the detached depth. The environmental information includes the ambient temperature, ambient humidity and carbon dioxide content.

[0011] Step 4: Confirmation of bridge material defects: Confirm the material defect impact index of the bridge based on the material information and environmental information of the bridge.

[0012] Step 5: Bridge traffic disease monitoring: monitor the traffic load information of the bridge, including the bridge stress and bridge vibration frequency at each monitoring time point in each monitoring time period.

[0013] Step 6. Confirmation of bridge traffic damage: According to the traffic load information of the bridge, confirm the traffic load damage impact index of the bridge.

[0014] Step 7. Confirmation of bridge damage level: Confirm the damage impact level of the bridge based on the bridge's structural damage impact index, material damage impact index and traffic load damage impact index.

[0015] Step 8. Bridge disease feedback: According to the impact level of the bridge disease, corresponding feedback is provided on the bridge disease diagnosis cloud platform.

[0016] Compared with the prior art, the present invention has the following beneficial effects: (1) By confirming the structural disease impact index of the bridge based on the structural information of each bridge part, the present invention avoids the deficiency of not considering the individual differences between the structural diseases of each bridge part, increases the attention to bridge deformation, ensures the accuracy of the assessment of bridge structural diseases, and further improves the reliability of bridge durability assessment, thereby ensuring the timeliness of the prediction of the development trend of bridge diseases and the accuracy of the subsequent judgment of the development speed of bridge structural diseases.

[0017] (2) The present invention conducts a comprehensive bridge disease diagnosis in multiple dimensions based on the structural diseases, material diseases and traffic load diseases of the bridge, thus breaking the current problem of insufficient attention paid to the diagnosis of bridge traffic diseases, thereby ensuring the effectiveness of bridge disease assessment, thereby improving the comprehensiveness of bridge disease diagnosis, and at the same time improving the targetedness of subsequent bridge maintenance and reinforcement decision-making, and improving the rationality of the formulation of bridge reinforcement plans.

[0018] (3) The present invention analyzes the material disease impact index of the bridge by setting the environmental interference factor of the bridge, thereby improving the accuracy of the bridge material disease analysis, and further improving the timeliness of the prediction of the development trend of the bridge material disease, thereby reducing the maintenance cost of the bridge disease.

[0019] (4) The present invention confirms the traffic load disease impact index of the bridge based on the bridge stress and bridge vibration frequency at each monitoring time point in each monitoring time period, thereby realizing the diagnosis and evaluation of the traffic load disease of the bridge, thereby improving the accuracy of the bridge disease diagnosis, and thus improving the accuracy of the measurement of the impact of traffic load disease on bridge disease. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0021] Figure 1 It is a schematic diagram of the connection of each step of the method of the present invention.

[0022] Figure 2It is a connection schematic diagram of the structural disease impact index confirmation step of the present invention.

[0023] Figure 3 It is a connection schematic diagram of the traffic load disease impact index confirmation step of the present invention. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] See also Figure 1 As shown, the present invention provides a bridge disease diagnosis and evaluation method based on monitoring and sensing technology, the method comprising: step one, bridge structure disease monitoring: monitoring the structural information of each bridge part, including settlement height, lateral displacement, offset angle, number of cracks, length, width and depth of each crack.

[0026] It should be added that the number of cracks is obtained by photographing the bridge with a camera mounted on a drone, thereby obtaining images of various parts of the bridge, and then using image recognition software to analyze and process the images, identify the characteristics of the cracks and count them.

[0027] It should be added that the crack length was monitored by a laser rangefinder carried by a drone.

[0028] It should be added that the crack width is obtained by magnifying the crack and observing it through a portable microscope carried by the drone, taking a microscopic image of the crack, and then measuring the crack width in the microscopic image through image analysis software to obtain the crack width.

[0029] It should be added that the crack depth is obtained by emitting ultrasonic waves through the ultrasonic transducer carried by the drone, and then measuring the time it takes for the ultrasonic waves to propagate around the bottom of the crack, the change in amplitude and other parameters, and calculating the crack depth based on the ultrasonic propagation speed and material properties.

[0030] It should be added that the settlement height is obtained through monitoring by a level instrument. Its working principle is as follows: a level instrument is an instrument that uses a level tube to provide a horizontal line of sight. Stable leveling base points (points with known elevations) are set up around the bridge. Level rods are erected at various monitoring locations and leveling base points on the bridge. The level instrument reads the readings on the level rod. According to the principle of leveling measurement, the elevation difference is equal to the backsight reading minus the foresight reading. Through multiple measurements and calculations, the elevation difference of various parts of the bridge relative to the leveling base point is obtained, thereby determining the settlement height. For example, the elevation of the top of a pier at the first measurement is After a period of time, the height is measured again. , then the settlement height is .

[0031] It should be added that the lateral displacement is obtained by monitoring through a laser displacement sensor, and its working principle is: the laser displacement sensor is mainly based on the principle of laser triangulation. It consists of a laser transmitter, an optical system, and a photoelectric detector. The laser transmitter emits a beam of laser to the bridge part. When the laser hits the surface of the bridge part, it will be reflected. The reflected light is received by the photoelectric detector through the optical system. When the bridge structure undergoes lateral displacement, the position of the reflected light will change. The photoelectric detector converts the optical signal into an electrical signal and calculates the displacement according to the triangular geometric relationship, that is, the lateral displacement of the bridge part.

[0032] It should be added that the offset angle is obtained through monitoring by a tilt sensor, and its working principle is: the tilt sensor based on the gravity principle has a sensitive axis inside. When the sensor is installed on the surface of the bridge structure, due to the action of gravity, the sensitive axis forms an angle with the direction of gravity. When the bridge offset angle changes, the angle between the sensitive axis of the sensor and the direction of gravity also changes. The sensor detects this angle change through an internal accelerometer or electrolyte principle. For example, for a capacitive tilt sensor, there are two capacitor plates inside. In the horizontal state, the capacitance value is in a balanced state. When tilting occurs, the relative position between the capacitor plates changes, and the capacitance value changes. The tilt angle is obtained by measuring the change in capacitance value and based on the relationship between the capacitance value and the tilt angle.

[0033] Step 2: Confirmation of bridge structure defects: Confirm the structural defect impact index of the bridge based on the structural information of each bridge part.

[0034] See also Figure 2 As shown, exemplarily, the determining of the structural disease impact index of the bridge includes: B1, calculating the crack disease impact index of the bridge according to the number of cracks in each bridge part, the length, width and depth of each crack .

[0035] Furthermore, the statistical bridge crack disease impact index includes: B1-1, recording the length, width and depth of each crack in each bridge part as , and , Number the bridge sections. , Number the cracks. .

[0036] B1-2. Calculate the crack impact index of each bridge part , , , and are the set permissible crack length, permissible crack width and permissible crack depth respectively. is the number of cracks.

[0037] It should be added that , and All of them are extracted from the technical specification table of bridge disease diagnosis.

[0038] B1-3. Record the number of cracks in each bridge part as .

[0039] B1-4. Calculate the impact index of crack damage in each bridge part , , and are the set permissible number of bridge cracks and the permissible crack impact index of the bridge, and then the average is calculated, and the calculation result is used as the crack disease impact index of the bridge, recorded as .

[0040] It should be added that and All of them are extracted from the technical specification table of bridge disease diagnosis.

[0041] B2. Calculate the bridge deformation damage impact index based on the settlement height, lateral displacement and offset angle of each bridge part .

[0042] Furthermore, the statistical deformation disease impact index of the bridge includes: B2-1, comparing the settlement height of each bridge part with the set allowable bridge settlement height.

[0043] B2-2. If the settlement height of a bridge part is greater than the set permissible bridge settlement height, the bridge part shall be recorded as an abnormal settlement bridge part.

[0044] B2-3. Count the number of bridge parts with abnormal settlement and the number of bridge parts, and then use the ratio of the number of bridge parts with abnormal settlement to the number of bridge parts as the settlement deviation index of the bridge, and record it as .

[0045] B2-4, according to The lateral displacement deviation index and the offset angle deviation index of the bridge are obtained by the same statistical method and recorded as and .

[0046] B2-5. Import the settlement deviation index, lateral displacement deviation index and offset angle deviation index of the bridge into the deformation disease influence index analysis model to obtain the deformation disease influence index of the bridge part and record it as .

[0047] It should be added that the formula of the deformation disease impact index analysis model is: , , and are the weights of the set settlement deviation index, lateral displacement deviation index and offset angle deviation index, respectively. , .

[0048] It should be added that the settlement of the bridge is directly related to the stability of the entire structure. When the bridge settles, especially the uneven settlement, the stress state of the bridge structure will change. For example, the settlement of the pier foundation will redistribute the internal force between the pier and the superstructure. The bridge may have additional bending moment and shear force. For a simply supported beam bridge, excessive settlement may cause the support conditions at the end of the bridge to change, causing cracks or local damage to the bridge, so it has the greatest impact on the deformation of the bridge. The lateral displacement will cause the structural components of the bridge to be laterally dislocated. For a continuous beam bridge or a rigid frame bridge, the lateral displacement may cause damage to the connection between the bridge and the pier, such as lateral shear deformation or voiding of the support. At the same time, the lateral displacement will also change the lateral force distribution of the bridge structure, reducing the resistance of the structure to lateral wind loads or lateral impact forces of vehicles. Within a certain range, the change in the offset angle of the bridge has a relatively small effect on the redistribution of the internal force of the structure. For example, for a small angle offset, the stress state between the bridge and the pier changes relatively slowly, and the structure itself may have a certain degree of adaptability, so its degree of harm is not as obvious as settlement and lateral displacement. Therefore, it is set , in order to facilitate analysis, The specific value can be 0.5. The specific value can be 0.3. The specific value can be 0.2.

[0049] B3. Select the maximum value from the crack disease impact index and deformation disease impact index of the bridge as the structural disease impact index of the bridge, recorded as .

[0050] The embodiment of the present invention confirms the structural disease impact index of the bridge according to the structural information of each bridge part, thereby avoiding the deficiency of not considering the individual differences between the structural diseases of each bridge part, increasing the attention to the deformation of the bridge, ensuring the accuracy of the assessment of the bridge structure disease, and further improving the reliability of the bridge durability assessment, thereby ensuring the timeliness of the prediction of the development trend of the bridge disease, and at the same time ensuring the accuracy of the judgment of the subsequent development speed of the bridge structure disease.

[0051] Step 3. Bridge material disease monitoring: monitor the material information and environmental information of the bridge. The material information includes the number of corroded parts of the steel bars, the corrosion area of ​​each corrosion part, the corrosion depth, and the number of detached parts of the concrete, the detached area of ​​each detached part and the detached depth. The environmental information includes the ambient temperature, ambient humidity and carbon dioxide content.

[0052] It should be added that the impact of carbon dioxide content on bridges is: concrete is an alkaline material, and the internal pore solution contains calcium hydroxide, with a pH value usually around 12-13. Carbon dioxide will react with calcium hydroxide to form carbonic acid. The changes in pore structure and increased permeability caused by carbonization will lead to reduced durability of concrete. For example, in a freeze-thaw cycle environment, carbonized concrete is more vulnerable to damage because moisture can more easily enter the interior of the concrete. The expansion force generated during freezing can cause peeling of the concrete surface and internal cracking. At the same time, the reduction in durability is also manifested as a weakening of resistance to chemical erosion, such as decreased resistance to corrosive environments such as acid rain and seawater. At the same time, when the carbon dioxide content in the air is high, under appropriate humidity conditions (such as relative humidity exceeding 60%), carbon dioxide will dissolve in the water film on the surface of the steel bar to form carbonic acid. Carbonic acid is a weak acid that will react chemically with the iron on the surface of the steel bar to generate ferrous ions and hydrogen, which in turn leads to corrosion of the steel bar.

[0053] It should be added that the number of corroded steel bars in bridges is obtained through monitoring by optical fiber sensors. The principle is as follows: optical fiber sensors (such as fiber grating sensors) are installed on the surface of steel bars. When steel bars are corroded, changes in the concentration of chemical substances in the surrounding environment (such as corrosive media such as chloride ions), changes in pH values, or expansion of steel bars will cause changes in the optical parameters of the optical fiber (such as wavelength, light intensity, etc.). By detecting the changes in these optical parameters and using the pre-established optical parameter-corrosion state relationship model, it is possible to determine whether the steel bars are corroded and count the number of corroded areas. For example, when the reflected wavelength of the fiber grating sensor drifts beyond a certain threshold, it indicates that corrosion may have occurred at the corresponding steel bar position, thereby counting the number of corroded steel bars in the bridge.

[0054] It should be added that the corrosion area of ​​the steel bars in the bridge is obtained by using a camera carried by a drone to photograph the steel bar surface of the bridge to obtain clear images, which are then transferred to a computer and processed using professional image analysis software. The image segmentation technology is used to separate the corroded area on the steel bar surface from the uncorroded area, and the area of ​​the corroded area is calculated based on the number of pixels and the known image scale.

[0055] It should be added that the corrosion depth of the steel bars in the bridge is obtained by monitoring with an ultrasonic thickness gauge. The ultrasonic thickness gauge is mainly composed of a probe and a host. The probe emits an ultrasonic pulse, which propagates in the steel bar. When it encounters the bottom surface of the steel bar (the side opposite to the corrosion layer), it will be reflected back and received by the probe. According to the propagation time of the ultrasonic wave in the steel bar and the known propagation speed of the ultrasonic wave in the steel bar, the formula (in is the steel bar thickness, is the ultrasonic wave propagation speed, The thickness of the steel bar is calculated by the propagation time. After the steel bar is corroded, the corrosion depth is obtained by comparing the thickness of the steel bar before and after corrosion. For example, when the steel bar is not corroded, its thickness is After a period of time, the thickness is measured. , the corrosion depth is .

[0056] It should be added that the method for obtaining the number of detached parts of concrete, the detached area of ​​each detached part and the detached depth is similar to the method for obtaining the number of corroded parts of steel bars, the corrosion area of ​​each corrosion part and the corrosion depth, and will not be repeated here.

[0057] It should be added that the ambient temperature is monitored by a temperature sensor installed on the bridge, the ambient humidity is monitored by a humidity sensor installed on the bridge, and the carbon dioxide content is monitored by a carbon dioxide sensor installed on the bridge.

[0058] Step 4: Confirmation of bridge material defects: Confirm the material defect impact index of the bridge based on the material information and environmental information of the bridge.

[0059] Exemplarily, the determination of the material disease impact index of the bridge includes: F1, calculating the steel bar corrosion impact index of the bridge according to the number of corrosion sites of the steel bars, the corrosion area and the corrosion depth of each corrosion site. .

[0060] Furthermore, the statistical steel bar corrosion impact index of the bridge includes: F1-1, summing up the corrosion areas of each corrosion site of the steel bar to obtain the total corrosion area of ​​the steel bar, and extracting the steel bar surface area of ​​the bridge from the bridge disease diagnosis cloud platform, and then taking the ratio of the total corrosion area of ​​the steel bar to the steel bar surface area as the steel bar corrosion area impact index, recorded as .

[0061] F1-2. Extract the maximum corrosion depth from the corrosion depth of each corrosion site of the steel bar and record it as .

[0062] F1-3. The average corrosion depth of each corrosion point of the steel bar is calculated as the average corrosion depth of the steel bar, which is recorded as .

[0063] F1-4. Statistical analysis of steel bar corrosion depth impact index , , is the set permissible steel bar corrosion depth.

[0064] It should be added that It is extracted from the technical specification table of bridge disease diagnosis.

[0065] F1-5. Record the number of corroded parts of the steel bars as .

[0066] F1-6. Extract the number of permissible steel bar corrosion locations of the bridge from the bridge disease diagnosis cloud platform, recorded as .

[0067] F1-7, if , then As the number of corrosion sites of the steel bar, the number of corrosion sites of the steel bar is affected by 1, and the number of corrosion sites of the steel bar is affected by 1. , The value is Or 1.

[0068] F1-8. Statistical bridge reinforcement corrosion impact index , .

[0069] F2. According to the number of concrete shedding points, the shedding area and shedding depth of each shedding point, the concrete shedding impact index of the bridge is obtained by the same statistical method as the bridge reinforcement corrosion impact index, and recorded as .

[0070] F3. Set the environmental interference factor of the bridge according to the ambient temperature, ambient humidity and carbon dioxide content of the bridge. .

[0071] Furthermore, the setting of the environmental interference factor of the bridge includes: F3-1, comparing the ambient temperature of the bridge with a set permissible bridge ambient temperature range.

[0072] F3-2: If the ambient temperature of the bridge is within the set permissible bridge ambient temperature range, the temperature interference factor is recorded as 0.

[0073] F3-3. If the ambient temperature of the bridge is greater than the upper limit of the set permissible bridge ambient temperature range, the ambient temperature is subtracted from the upper limit of the set permissible bridge ambient temperature range, and the ratio of the difference to the upper limit of the set permissible bridge ambient temperature range is used as the temperature interference factor.

[0074] F3-4. If the ambient temperature of the bridge is lower than the set lower limit of the permissible bridge ambient temperature range, the set lower limit of the permissible bridge ambient temperature range is subtracted from the ambient temperature, and the ratio of the difference to the set lower limit of the permissible bridge ambient temperature range is used as the temperature interference factor, thereby obtaining the temperature interference factor of the bridge.

[0075] F3-5. Compare the ambient humidity of the bridge with the set permissible ambient humidity of the bridge. If the ambient humidity of the bridge is less than the set permissible ambient humidity of the bridge, the ratio of the ambient humidity of the bridge to the set permissible ambient humidity of the bridge is used as the ambient humidity interference factor. Otherwise, 1 is used as the ambient humidity interference factor, thereby obtaining the humidity interference factor of the bridge.

[0076] F3-6. The carbon dioxide content interference factor of the bridge can be obtained by analyzing it in the same way as the humidity interference factor of the bridge.

[0077] F3-7. Calculate the average of the temperature interference factor, humidity interference factor and carbon dioxide content interference factor of the bridge, and use the calculated result as the environmental interference factor of the bridge, recorded as .

[0078] The embodiment of the present invention analyzes the material disease impact index of the bridge by setting the environmental interference factor of the bridge, thereby improving the accuracy of the bridge material disease analysis, and further improving the timeliness of the prediction of the development trend of the bridge material disease, thereby reducing the maintenance cost of the bridge disease.

[0079] F4. Calculate the material damage impact index of the bridge , , and are the weights of the steel bar corrosion impact index and concrete shedding impact index, respectively. , .

[0080] It should be added that steel bars are the main load-bearing components in concrete bridges, bearing a large part of the tension and other forces, and are crucial to maintaining the overall stability and bearing capacity of the bridge structure. Once the steel bars are corroded, their cross-sectional area will gradually decrease, resulting in a significant decrease in the mechanical properties of the steel bars, such as strength and ductility. The corrosion products will also cause the bond between the steel bars and concrete to decrease, further damaging the collaborative working performance of the structure. Severe steel bar corrosion may cause serious stress hazards in the bridge structure in a short period of time, and even cause sudden structural damage, posing an extremely serious threat to the safe use of the bridge. Concrete shedding mainly affects the appearance of the bridge and its protective effect on the steel bars. Although concrete shedding will expose the steel bars and increase the risk of steel bar corrosion, in the initial stage, concrete shedding itself usually does not directly lead to catastrophic damage to the force system of the bridge structure. As long as timely measures are taken to repair the shedding parts and protect the exposed steel bars, the bridge structure can generally be maintained in normal use for a certain period of time. Therefore, from the perspective of the immediate impact on structural safety, the harm of steel bar corrosion is more prominent, so setting , in order to facilitate analysis, The specific value can be 0.6. The specific value can be 0.4.

[0081] Step 5: Bridge traffic disease monitoring: monitor the traffic load information of the bridge, including the bridge stress and bridge vibration frequency at each monitoring time point in each monitoring time period.

[0082] It should be added that each monitoring time period refers to monitoring the traffic flow on the bridge at each monitoring time point, comparing the traffic flow at each monitoring time point with the set permitted traffic flow. When the traffic flow at a certain monitoring time point is greater than the set permitted traffic flow, the monitoring time point is marked, thereby obtaining each marked monitoring time point.

[0083] Check each marked monitoring time point in chronological order, starting from the first marked monitoring time point where the traffic volume is greater than the permitted traffic volume, to the last marked monitoring time point where the subsequent consecutive traffic volume is greater than the permitted traffic volume ends, and divide this period of continuous time points to form a monitoring time period. Similarly, divide all combinations of continuous marked monitoring time points that meet the above conditions to obtain monitoring time periods composed of monitoring time points where the traffic volume is greater than the set permitted traffic volume.

[0084] For example, the permitted traffic volume is set to 100 vehicles every 10 minutes, and the traffic volume is recorded every 10 minutes at the monitoring time point. Assuming that the traffic volume at the three consecutive monitoring time points of 9:10 am, 9:20 am, and 9:30 am is greater than 100 vehicles, then "9:10 am - 9:30 am" is a monitoring time period. If the subsequent traffic volume at 10:20 am and 10:30 am is greater than or equal to the permitted traffic volume and the traffic volume at 10:40 am is less than the permitted traffic volume, then "10:20 am - 10:30 am" is another monitoring time period.

[0085] It should be added that the bridge stress is monitored by strain gauges installed on the bridge.

[0086] It should be added that the bridge vibration frequency is monitored by vibration sensors installed on the bridge.

[0087] Step 6. Confirmation of bridge traffic damage: According to the traffic load information of the bridge, confirm the traffic load damage impact index of the bridge.

[0088] See also Figure 3 As shown, exemplarily, the determining of the traffic load disease impact index of the bridge includes: G1, according to the bridge stress at each monitoring time point in each monitoring time period, calculating the stress disease impact index of the bridge .

[0089] Furthermore, the statistical bridge stress disease impact index includes: G1-1, taking the monitoring time point as the horizontal coordinate and the bridge stress as the vertical coordinate, constructing a bridge stress change curve of the bridge in each monitoring time period.

[0090] G1-2. Select the maximum bridge stress of the bridge in each monitoring time period from the bridge stress change curve in each monitoring time period and record it as , is the monitoring time period number, .

[0091] G1-3. Statistical analysis of the bridge stress peak value excess ratio in each monitoring period , , is the maximum allowable stress of the bridge.

[0092] It should be added that It is extracted from the technical specification table of bridge disease diagnosis.

[0093] G1-4. Extract the minimum bridge stress of the bridge in each monitoring time period from the bridge stress change curve in each monitoring time period, and then take the difference between the maximum bridge stress and the minimum bridge stress as the stress fluctuation amplitude of the bridge in each monitoring time period, recorded as .

[0094] G1-5. According to the set stress warning value, a reference line is constructed from the bridge stress change curve of the bridge in each monitoring time period, and then the length of the curve segment above the reference line and the total length of the curve segment of the bridge in each monitoring time period are extracted and recorded as and .

[0095] G1-6. Statistical analysis of the stress exceeding warning time ratio of bridges in each monitoring period , .

[0096] G1-7. Statistical bridge stress disease impact index , , is the number of monitoring time periods, , and are the stress peak value exceeding ratio, stress fluctuation amplitude and stress exceeding warning time ratio of the reference respectively. , and are the weights of the set stress peak value excess ratio, stress fluctuation amplitude and stress excess warning time ratio, respectively. , .

[0097] It should be added that , and All of them are extracted from the technical specification table of bridge disease diagnosis.

[0098] It should be added that the peak stress excess ratio reflects the degree to which the peak stress borne by the bridge structure under specific working conditions exceeds the design allowable stress value. When the peak stress significantly exceeds the design allowable value, it means that the bridge structure is facing a great risk of overload at that moment, and its internal load-bearing components may be in an extremely dangerous stress state in an instant, which may exceed the ultimate strength of the material itself, directly leading to the destruction of the components and even causing catastrophic consequences such as the collapse of the entire bridge structure. Once this happens, there is almost no buffer time to take remedial measures, which is the most direct and serious threat to the safety of the bridge. The stress excess warning time ratio reflects the stress excess warning time of the bridge structure. The ratio of the cumulative time of the value to the total observation time. When the stress continues to exceed the warning value, although it may not have reached the extremely dangerous level of the stress peak exceedance ratio, this indicates that the bridge structure has been in a relatively dangerous stress state for a long time, which will continuously "consume" the various components of the bridge structure, accelerate the fatigue damage of the components, the degradation of material properties, etc., and thus affect the long-term durability and safety of the bridge. It reflects that the bridge structure is subjected to stress beyond the normal range for a relatively long period of time. It is a continuous risk warning and has an important impact on the long-term stable operation of the bridge. The stress fluctuation amplitude refers to the range of fluctuations in the stress of the bridge structure within a certain period of time. Although stress fluctuations will cause bridge components to be in a constantly changing stress state and increase the risk of fatigue damage to components, in general, as long as the stress fluctuation amplitude is within the design allowable range or is only slightly exceeded, its impact on the safety and durability of the bridge structure is relatively mild compared to the stress peak exceedance ratio and the stress exceedance warning time ratio. For example, the bridge stress will fluctuate to a certain extent under normal traffic loads, but it usually does not immediately cause serious structural problems. Therefore, setting , The specific value can be 0.5. The specific value can be 0.2. The specific value can be 0.3.

[0099] G2. According to the statistical method of bridge stress disease impact index, the vibration frequency disease impact index of the bridge is obtained in the same way and recorded as .

[0100] G3. The average value of the stress disease impact index and the vibration frequency disease impact index of the bridge is calculated as the traffic load impact index of the bridge and recorded as .

[0101] The embodiment of the present invention confirms the traffic load disease impact index of the bridge according to the bridge stress and bridge vibration frequency at each monitoring time point in each monitoring time period, thereby realizing the diagnosis and evaluation of the traffic load disease of the bridge, thereby improving the accuracy of the diagnosis of bridge diseases, and thus improving the accuracy of measuring the impact of traffic load diseases on bridge diseases.

[0102] Step 7. Confirmation of bridge damage level: Confirm the damage impact level of the bridge based on the bridge's structural damage impact index, material damage impact index and traffic load damage impact index.

[0103] The embodiments of the present invention perform a comprehensive bridge disease diagnosis in multiple dimensions according to the structural diseases, material diseases and traffic load diseases of the bridge, thereby breaking the current problem of insufficient attention to the diagnosis of bridge traffic diseases, and further ensuring the effectiveness of bridge disease assessment, thereby improving the comprehensiveness of bridge disease diagnosis, while improving the targetedness of subsequent bridge maintenance and reinforcement decision-making, and improving the rationality of the formulation of bridge reinforcement plans.

[0104] Exemplarily, the confirming of the damage impact level of the bridge includes: calculating the average value of the structural damage impact index, material damage impact index and traffic load damage impact index of the bridge as the damage impact index of the bridge.

[0105] The disease impact index of the bridge is matched and compared with the disease impact index interval corresponding to the disease impact level of each bridge to obtain the disease impact level of the bridge.

[0106] Step 8. Bridge disease feedback: According to the impact level of the bridge disease, corresponding feedback is provided on the bridge disease diagnosis cloud platform.

[0107] The above contents are merely examples and explanations of the concept of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the concept of the invention or exceed the scope defined by the present invention, they shall all fall within the protection scope of the present invention.

Claims

1. A bridge disease diagnosis and evaluation method based on monitoring and sensing technology, characterized by: The method includes: Step 1: Bridge structure defect monitoring: monitor the structural information of each bridge part, including settlement height, lateral displacement, offset angle, number of cracks, length, width and depth of each crack; Step 2: Confirmation of bridge structure defects: Confirm the structural defect impact index of the bridge based on the structural information of each bridge part; Step 3: Bridge material disease monitoring: monitor the material information and environmental information of the bridge. The material information includes the number of corrosion sites of the steel bars, the corrosion area of ​​each corrosion site, the corrosion depth, and the number of detached sites of the concrete, the detached area of ​​each detached site, and the detached depth. The environmental information includes the ambient temperature, ambient humidity, and carbon dioxide content. Step 4: Confirmation of bridge material defects: Confirm the bridge material defect impact index based on the bridge material information and environmental information; Step 5: Bridge traffic disease monitoring: monitoring the traffic load information of the bridge, including the bridge stress and bridge vibration frequency at each monitoring time point in each monitoring period; Step 6: Confirmation of bridge traffic damage: According to the traffic load information of the bridge, confirm the traffic load damage impact index of the bridge; Step 7: Confirm the bridge damage level: Confirm the bridge damage impact level based on the bridge's structural damage impact index, material damage impact index and traffic load damage impact index; Step 8: Bridge disease level feedback: According to the bridge disease impact level, corresponding feedback is provided on the bridge disease diagnosis cloud platform; The structural damage impact index of the bridge to be confirmed includes: B1. Calculate the bridge crack disease impact index based on the number of cracks in each bridge part, the length, width and depth of each crack ; B2. Calculate the bridge deformation damage impact index based on the settlement height, lateral displacement and offset angle of each bridge part ; B3. Select the maximum value from the crack disease impact index and deformation disease impact index of the bridge as the structural disease impact index of the bridge, denoted as ; The statistical bridge crack disease impact index includes: The length, width and depth of each crack in each bridge part are recorded as , and , Number the bridge sections. , Number the cracks. ; Statistical analysis of crack impact index at each bridge location , , , and are the set permissible crack length, permissible crack width and permissible crack depth respectively. is the number of cracks; The number of cracks in each bridge part is recorded as ; Statistical analysis of crack disease impact index at each bridge location , , and are the set permissible number of bridge cracks and the permissible crack impact index of the bridge, and then the average is calculated, and the calculation result is used as the crack disease impact index of the bridge, recorded as ; The statistical bridge deformation disease impact index includes: Compare the settlement height of each bridge part with the set permissible bridge settlement height; If the settlement height of a bridge part is greater than the set permissible bridge settlement height, the bridge part will be recorded as an abnormal settlement bridge part; The number of bridge parts with abnormal settlement and the number of bridge parts are counted, and then the ratio of the number of bridge parts with abnormal settlement to the number of bridge parts is used as the settlement deviation index of the bridge and recorded as ; according to The lateral displacement deviation index and the offset angle deviation index of the bridge are obtained by the same statistical method and recorded as and ; The settlement deviation index, lateral displacement deviation index and offset angle deviation index of the bridge are introduced into the deformation disease influence index analysis model to obtain the deformation disease influence index of the bridge, which is recorded as .

2. According to claim 1, a bridge disease diagnosis and evaluation method based on monitoring and sensing technology is characterized by: The material disease impact index for confirming the bridge includes: F1. Calculate the steel bar corrosion impact index of the bridge based on the number of steel bar corrosion sites, the corrosion area and corrosion depth of each corrosion site ; F2. According to the number of concrete shedding points, the shedding area and shedding depth of each shedding point, the concrete shedding impact index of the bridge is obtained by the same statistical method as the bridge reinforcement corrosion impact index, and recorded as ; F3. Set the environmental interference factor of the bridge according to the ambient temperature, ambient humidity and carbon dioxide content of the bridge. ; F4. Calculate the material damage impact index of the bridge , , and are the weights of the steel bar corrosion impact index and concrete shedding impact index, respectively. , .

3. The bridge disease diagnosis and evaluation method based on monitoring and sensing technology according to claim 2 is characterized by: The statistical bridge reinforcement corrosion impact index includes: The corrosion areas of each corroded part of the steel bar are summed to obtain the total corrosion area of ​​the steel bar, and the steel bar surface area of ​​the bridge is extracted from the bridge disease diagnosis cloud platform. Then, the ratio of the total corrosion area of ​​the steel bar to the steel bar surface area is used as the steel bar corrosion area influence index, which is recorded as ; The maximum corrosion depth is extracted from the corrosion depth of each corrosion site of the steel bar and recorded as ; The average corrosion depth of each corrosion point of the steel bar is calculated as the average corrosion depth of the steel bar, which is recorded as ; Statistical Corrosion Depth Impact Index of Steel Bars , , is the set permissible reinforcement corrosion depth; The number of corroded parts of the steel bar is recorded as ; The number of permissible steel bar corrosion locations of the bridge is extracted from the bridge disease diagnosis cloud platform and recorded as ; like , then As the number of corrosion sites of the steel bar, the number of corrosion sites of the steel bar is affected by 1, and the number of corrosion sites of the steel bar is affected by 1. , The value is or 1; Statistical analysis of the steel reinforcement corrosion impact index of bridges , .

4. The bridge disease diagnosis and evaluation method based on monitoring and sensing technology according to claim 2 is characterized by: The environmental interference factors for setting the bridge include: Compare the ambient temperature of the bridge with the set permissible ambient temperature range of the bridge; If the ambient temperature of the bridge is within the set permissible bridge ambient temperature range, the temperature interference factor is recorded as 0; If the ambient temperature of the bridge is greater than the upper limit of the set permissible bridge ambient temperature range, the ambient temperature is subtracted from the upper limit of the set permissible bridge ambient temperature range, and the ratio of the difference to the upper limit of the set permissible bridge ambient temperature range is used as the temperature interference factor; If the ambient temperature of the bridge is less than the lower limit of the set permissible bridge ambient temperature range, the set lower limit of the permissible bridge ambient temperature range is subtracted from the ambient temperature, and the ratio of the difference to the set lower limit of the permissible bridge ambient temperature range is used as the temperature interference factor, thereby obtaining the temperature interference factor of the bridge; The ambient humidity of the bridge is compared with the set permissible ambient humidity of the bridge. If the ambient humidity of the bridge is less than the set permissible ambient humidity of the bridge, the ratio of the ambient humidity of the bridge to the set permissible ambient humidity of the bridge is used as the ambient humidity interference factor. Otherwise, 1 is used as the ambient humidity interference factor, thereby obtaining the humidity interference factor of the bridge. The carbon dioxide content interference factor of the bridge can be obtained by analyzing the interference factor of bridge humidity in the same way. The temperature interference factor, humidity interference factor and carbon dioxide content interference factor of the bridge are averaged and the calculated result is used as the environmental interference factor of the bridge, recorded as .

5. The bridge disease diagnosis and evaluation method based on monitoring and sensing technology according to claim 1 is characterized by: The traffic load damage impact index of the bridge to be confirmed includes: G1. According to the bridge stress at each monitoring time point in each monitoring period, calculate the bridge stress disease impact index ; G2. According to the statistical method of bridge stress disease impact index, the vibration frequency disease impact index of the bridge is obtained in the same way and recorded as ; G3. The average value of the stress disease impact index and the vibration frequency disease impact index of the bridge is calculated as the traffic load impact index of the bridge and recorded as .

6. The bridge disease diagnosis and evaluation method based on monitoring and sensing technology according to claim 5 is characterized by: The statistical bridge stress disease impact index includes: With the monitoring time point as the horizontal coordinate and the bridge stress as the vertical coordinate, a bridge stress change curve of the bridge in each monitoring time period is constructed; The maximum bridge stress of the bridge in each monitoring time period is selected from the bridge stress change curve in each monitoring time period and recorded as , is the monitoring time period number, ; Statistical analysis of the bridge stress peak value excess ratio in each monitoring period , , is the maximum allowable stress of the bridge; The minimum bridge stress of the bridge in each monitoring time period is extracted from the bridge stress change curve in each monitoring time period, and then the difference between the maximum bridge stress and the minimum bridge stress is taken as the stress fluctuation amplitude of the bridge in each monitoring time period, which is recorded as ; According to the set stress warning value, a reference line is constructed from the bridge stress change curve of the bridge in each monitoring time period, and then the length of the curve segment above the reference line and the total length of the curve segment of the bridge in each monitoring time period are extracted and recorded as and ; Statistical analysis of the stress exceeding warning time ratio of the bridge in each monitoring period , ; Statistical analysis of stress damage index of bridges , , is the number of monitoring time periods, , and are the stress peak value exceeding ratio, stress fluctuation amplitude and stress exceeding warning time ratio of the reference respectively. , and are the weights of the set stress peak value excess ratio, stress fluctuation amplitude and stress excess warning time ratio, respectively. , .

7. The bridge disease diagnosis and evaluation method based on monitoring and sensing technology according to claim 1 is characterized by: The confirmation of the damage impact level of the bridge includes: The average calculation result of the structural disease impact index, material disease impact index and traffic load disease impact index of the bridge is used as the disease impact index of the bridge; The disease impact index of the bridge is matched and compared with the disease impact index interval corresponding to the disease impact level of each bridge to obtain the disease impact level of the bridge.

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