Bridge and culvert floating type water level intelligent detection and early warning system

Abstract

The present application relates to bridge and culvert floating type water level intelligent detection and early warning system, including water level sensing trigger unit, cloud intelligent processing unit, field warning unit and emergency dispatch unit;Water level sensing trigger unit adopts double floating magnetic coupling non-contact trigger mechanism and water level gradient detection module, through NB-IoT low power consumption network and cloud connection;Cloud realizes hierarchical warning and automatic voice call;Field sets up red light, LED screen, directional voice, automatic gate multiple warning;Based on GIS, emergency personnel automatic dispatch is realized.The present application solves the problems of poor timeliness of field bridge and culvert manual inspection, low reliability of existing equipment, lack of closed loop disposal, has the advantages of high reliability, low power consumption, low cost, good warning effect, fast response speed, can realize whole process closed loop safety protection under unattended, especially suitable for flood season water level monitoring and early warning of field no electricity bridge and culvert, greatly improves the bridge and culvert flood season traffic safety guarantee ability.

Description

Technical Field

[0001] This invention relates to the field of bridge and culvert safety monitoring technology, specifically to a floating intelligent water level detection and early warning system for bridges and culverts. Background Technology

[0002] Numerous rural road bridges and culverts are distributed in mountainous and hilly areas of my country. These bridges and culverts are important components of rural roads and trunk highways. During the flood season, heavy rainfall can easily cause short-term water accumulation or flooding at these locations. The rapid rise in water levels poses a serious threat to the structural safety of the bridges and culverts and to traffic safety. On the one hand, flood erosion can lead to structural damage such as hollowing out of bridge pier foundations, displacement of supports, and cracking of the bridge deck, and in severe cases, even bridge collapse. On the other hand, drivers who misjudge the depth of the water and attempt to cross it are prone to accidents such as vehicles stalling in the water or being swept away by the flood.

[0003] Currently, water level monitoring of bridges and culverts in the field mainly relies on manual inspection. Although some electronic water level monitoring devices have emerged in the existing technology, most of them have problems such as complex structure, high cost, poor reliability, and unsuitability for harsh field environments: contact water level sensors are prone to corrosion and failure when immersed in sewage for a long time, while non-contact radar or ultrasonic water level gauges are expensive and consume a lot of power, making it difficult to promote and apply them on a large scale in bridges and culverts in the field without power supply; at the same time, existing equipment generally lacks a closed-loop management mechanism for on-site warning and emergency dispatch, and often only realizes the data collection function, failing to form a complete safety protection chain from monitoring and early warning to on-site disposal.

[0004] Therefore, there is an urgent need to propose a floating intelligent water level detection and early warning system for bridges and culverts to solve the above problems. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a floating intelligent water level detection and early warning system for bridges and culverts. It has advantages such as simple structure, high reliability, low cost, adaptability to power-free environments in the field, and the ability to achieve closed-loop management throughout the entire process. It solves the problems of existing field bridge and culvert water level monitoring relying on manual inspection, which has poor timeliness, high labor intensity, high cost, and slow response, and existing electronic monitoring equipment, which has poor reliability, high cost, high power consumption, difficulty in adapting to harsh field environments, and lack of closed-loop handling mechanism.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a floating intelligent water level detection and early warning system for bridges and culverts, comprising a water level sensing triggering unit, a cloud-based intelligent processing unit, an on-site warning unit, and an emergency dispatch unit;

[0007] The water level sensing triggering unit includes a vertical guide rod, a main float, a spare float, a magnetic coupling triggering mechanism, and a water level gradient detection module;

[0008] The main float and the backup float rise and fall with the water level along the vertical guide rod. The magnetic coupling triggering mechanism adopts a non-contact magnetic induction design and triggers an early warning signal when the water level reaches a preset threshold. The water level gradient detection module is used to collect water level change rate data in real time.

[0009] The cloud-based intelligent processing unit and the water level sensing triggering unit are connected via an NB-IoT network. The unit is used to receive trigger signals and water level data, execute hierarchical early warning logic, automatically push voice calls and SMS warnings to preset responsible persons, and store the early warning data in the cloud.

[0010] The on-site warning unit is set at the entrances at both ends of the bridge and is wirelessly connected to the cloud-based intelligent processing unit. It includes a traffic light warning module, an LED information display screen, a directional voice broadcast module, and an infrared vehicle detection module, which are used to automatically warn passing vehicles and pedestrians when the warning is triggered.

[0011] The emergency dispatch unit is connected to the cloud-based intelligent processing platform, which is used to automatically dispatch the nearest emergency personnel based on GIS location information and generate standardized emergency response process guidelines.

[0012] Furthermore, the magnetic coupling triggering mechanism includes a permanent magnet disposed inside the float and multiple reed switches disposed at different heights on the guide rod; the reed switches are sealed with epoxy resin and completely isolated from the water; the main float and the backup float are spaced vertically to form a dual-redundant triggering mechanism, and an early warning can be initiated by triggering any float.

[0013] Furthermore, the vertical guide rod has a self-cleaning coating on its surface and an anti-sludge base at its bottom; the main float and the spare float are made of high-density polyethylene corrosion-resistant material, filled with closed-cell foam, and a polytetrafluoroethylene wear-resistant guide ring is provided between the float and the guide rod.

[0014] Furthermore, the water level gradient detection module includes a magnetostrictive liquid level sensor with a sampling frequency of not less than 1 time / minute, used to calculate the water level rise rate; the cloud-based intelligent processing unit has four preset warning thresholds: blue warning, yellow warning, orange warning and red warning, and dynamically adjusts the warning level according to the current water level height and water level rise rate.

[0015] Furthermore, the cloud-based intelligent processing unit includes an automatic calling module. After the warning is triggered, the automatic calling module automatically dials the phone number of a preset responsible person. If the first call is not answered, it will automatically redial after 30 seconds. If the call is not answered after 3 consecutive times, it will automatically dial the phone number of an alternative responsible person. After the call is connected, it plays a pre-recorded voice warning message, which includes the location of the bridge and culvert, the current water level, and the warning level.

[0016] Furthermore, the directional voice broadcast module uses a phased array directional speaker to play warning voice messages only in the direction of oncoming vehicles, thus avoiding noise pollution to the surrounding environment; when the infrared vehicle detection module detects a vehicle approaching within 50 meters, it automatically triggers the directional voice broadcast, and the broadcast content is dynamically adjusted according to the warning level.

[0017] Furthermore, the on-site warning unit also includes an automatic lifting barrier gate and a video capture module; when a red alert is triggered, the automatic lifting barrier gate drops to physically block the vehicle, and the video capture module automatically captures and records evidence of vehicles entering the warning area, with the captured photos uploaded to the cloud for storage in real time.

[0018] Furthermore, the system also includes a solar power supply unit, comprising a monocrystalline silicon solar panel, a lithium iron phosphate battery, and a power management module; the power management module adopts a low-power design, with a standby power consumption of no more than 50μA, and can support the system to work normally for no less than 30 days during continuous cloudy and rainy days.

[0019] Furthermore, the emergency dispatch unit has a built-in bridge and culvert basic database and an emergency personnel GIS database. After an early warning is triggered, it automatically calculates the real-time distance and arrival time of surrounding emergency personnel, automatically dispatches orders according to the distance priority principle, and pushes standardized handling guidelines containing bridge and culvert locations, risk levels, handling procedures, and surrounding detour routes to the dispatching personnel.

[0020] Furthermore, it also includes an early warning method applied to the system, comprising the following steps:

[0021] S1. Daily monitoring: The water level sensing trigger unit collects water level data and water level change rate in real time, and reports the data to the cloud periodically through the NB-IoT network. The system is in a low-power standby state.

[0022] S2. Warning Trigger: When the water level rises and triggers the magnetic coupling trigger mechanism, or when the rate of water level rise exceeds the preset threshold, the system immediately wakes up from standby mode and sends a trigger signal and real-time water level data to the cloud intelligent processing unit.

[0023] S3, Tiered Early Warning: The cloud-based intelligent processing unit determines the early warning level based on the current water level height and the rate of rise, and initiates the corresponding level of early warning process;

[0024] S4. Multi-channel notification: Automatically makes voice calls and sends text messages to the responsible person, while simultaneously issuing control commands to the on-site warning unit;

[0025] S5. On-site warning: The on-site warning unit activates a flashing red light, displays warning information on the LED screen, and broadcasts directional voice messages. When a red warning is issued, the gate automatically closes to physically intercept the vehicle and captures evidence.

[0026] S6. Emergency Dispatch: Based on GIS, automatically dispatch the nearest emergency personnel, push standardized handling guidelines, track the handling progress, and continue until the warning is lifted.

[0027] Compared with the prior art, the technical solution of this application has the following beneficial effects:

[0028] 1. This invention adopts a magnetic coupling non-contact triggering design. Electronic components such as reed switches are completely sealed inside the guide rod and do not directly contact the water body, thus completely solving the problem of long-term immersion corrosion failure of traditional contact sensors. The dual float redundancy design effectively avoids the problem of missed alarms caused by float jamming and debris entanglement. The trigger threshold is precisely calibrated, so it will not give false alarms due to waves or slight rise in water level, and can trigger in time at dangerous water levels. The float and guide rod are made of corrosion-resistant and wear-resistant materials. With the addition of a self-cleaning coating and anti-siltation base, it can work stably for a long time in complex water environments such as turbid floods and siltation, with a service life of more than 5 years, which greatly reduces maintenance costs.

[0029] 2. This invention adopts NB-IoT low-power communication technology and solar power supply solution, with standby power consumption controlled below 50μA. It can work normally for more than 30 days in continuous cloudy and rainy weather, and does not require external mains power. It is especially suitable for installation and use in scattered outdoor bridges and culverts.

[0030] 3. This invention not only monitors the static water level height, but also calculates the water level rise rate in real time through the water level gradient detection module. Combining the two dimensions, a four-level early warning model is established. In extreme cases of rapid water level rise, a high-level early warning can be triggered in advance, buying more time for emergency response. The automatic voice call mechanism adopts a missed call redial and backup contact mechanism to ensure that the early warning information is 100% delivered to the responsible person, solving the problem that traditional SMS early warnings are easily ignored.

[0031] 4. This invention sets up integrated warning units at both ends of the bridge and culvert, using multiple means such as traffic lights, LED screens, directional voice, and automatic gates to issue warnings. The directional speakers only broadcast in the direction of oncoming traffic to avoid noise pollution. Infrared vehicle detection enables the broadcast to be issued as soon as a vehicle arrives. When a red warning is issued, the gate will automatically close to physically intercept the vehicle and capture the image as evidence. A safety barrier can be automatically established before maintenance personnel arrive at the site, effectively preventing vehicles from accidentally entering the area. Attached Figure Description

[0032] Figure 1 This is a framework diagram of the bridge and culvert floating intelligent water level detection and early warning system of the present invention;

[0033] Figure 2 This is a schematic diagram of the data connection of the floating intelligent water level detection and early warning system for bridges and culverts of the present invention;

[0034] Figure 3 This is a flowchart of the intelligent water level detection and early warning process for bridges and culverts according to the present invention. Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] Please see Figure 1-3 The bridge and culvert floating intelligent water level detection and early warning system in this embodiment includes a water level sensing triggering unit, a cloud-based intelligent processing unit, an on-site warning unit, and an emergency dispatch unit. The water level sensing triggering unit includes a vertical guide rod, a main float, a backup float, a magnetic coupling triggering mechanism, and a water level gradient detection module. The main float and the backup float rise and fall with the water level along the vertical guide rod. The magnetic coupling triggering mechanism adopts a non-contact magnetic induction design and triggers an early warning signal when the water level reaches a preset threshold. The water level gradient detection module is used to collect water level change rate data in real time. The cloud-based intelligent processing unit communicates with the water level sensing triggering unit through an NB-IoT network. The system is designed to receive trigger signals and water level data, execute tiered early warning logic, automatically send voice calls and SMS alerts to pre-defined responsible personnel, and store the early warning data in the cloud. On-site warning units are located at the entrances of both ends of the bridge and culvert, wirelessly connected to the cloud-based intelligent processing unit. These units include traffic light warning modules, LED information displays, directional voice broadcasting modules, and infrared vehicle detection modules, used to automatically warn passing vehicles and pedestrians when an early warning is triggered. The emergency dispatch unit connects to the cloud-based intelligent processing platform, used to automatically dispatch the nearest emergency personnel based on GIS location information and generate standardized emergency response procedure guidelines.

[0037] This invention also provides a floating intelligent water level detection and early warning method for bridges and culverts, which includes six steps: daily monitoring, early warning triggering, graded early warning, multi-channel notification, on-site warning and emergency dispatch, realizing closed-loop management of the entire process from water level monitoring to emergency response.

[0038] Example 1: Application of Standard National and Provincial Highway Bridges and Culverts

[0039] This embodiment is applied to a bridge and culvert crossing a river on a national or provincial highway in a mountainous area. The bridge and culvert have a span of 8m, a design warning water level of 1.5m, and are two-way, two-lane highway bridges and culverts with high daily traffic volume. The highest water level during the flood season can reach 2.2m.

[0040] A floating intelligent water level detection and early warning system for bridges and culverts includes a water level sensing trigger unit, a cloud-based intelligent processing unit, an on-site warning unit, an emergency dispatch unit, and a solar power supply unit. The water level sensing trigger unit is installed next to the pier on the upstream side of the bridge and culvert, 0.8m away from the pier, and is fixed to the side of the pier by stainless steel clamps. The on-site warning units are respectively set at the entrances at both ends of the bridge and culvert, 50m away from the bridge and culvert. The solar power supply unit is installed on the top of the on-site warning poles.

[0041] The water level sensing trigger unit includes a vertical guide rod, a main float, a spare float, a magnetic coupling trigger mechanism, and a water level gradient detection module. The vertical guide rod is made of 304 stainless steel, with an outer diameter of 32mm, a wall thickness of 3mm, and a total length of 3m. Its surface is coated with a 20μm thick PTFE self-cleaning coating with a contact angle greater than 110°, preventing sediment adhesion. The bottom of the guide rod is equipped with a 50cm diameter, 20cm thick C30 concrete anti-siltation base, buried 30cm below the riverbed to prevent the guide rod from being washed away by floods and to prevent sediment accumulation at the bottom. The upper part of the guide rod is fixed to the bridge pier by two stainless steel clamps spaced 1m apart.

[0042] Both the main float and the spare float are made of high-density polyethylene (HDPE) through rotational molding in one piece, with a wall thickness of 5mm. They are cylindrical in shape with a diameter of 20cm and a height of 25cm, and the internal filling density is 30kg / m³. 3 The polyurethane closed-cell foam ensures that the float will not sink even if the outer shell is damaged. The main float is located below, corresponding to the orange and red warning trigger positions, while the spare float is located 30cm above the main float, corresponding to the highest water level limit trigger position. Both floats have guide holes in their centers that fit with the guide rods. Three evenly distributed PTFE wear-resistant guide rings are embedded in the guide holes. The guide rings have an inner diameter of 33mm and a gap of 1mm with the guide rod, resulting in a friction coefficient of less than 0.04, ensuring that the floats can move up and down flexibly along the guide rods without getting stuck. The outer surface of the floats is also coated with a PTFE self-cleaning coating to prevent aquatic organisms from adhering.

[0043] The magnetic coupling triggering mechanism includes a neodymium iron boron permanent magnet located at the center of each float. The permanent magnet measures φ20mm × 10mm, is nickel-plated for corrosion protection, and has a magnetic field strength of 3000Gs. Four reed switches are sealed and installed at different heights inside the guide rod, corresponding to the four water levels from bottom to top: blue warning (1.2m), yellow warning (1.35m), orange warning (1.5m), and red warning (1.8m). The reed switches are normally open type with a rated power of 10W, and the contact resistance is less than 100mΩ. Each reed switch pin is welded with a wire and then vacuum-sealed with epoxy resin. The sealing depth is not less than 5cm, completely isolated from the water body, and the waterproof rating reaches IP68; the reed switch action distance is 3cm±0.5cm. When the permanent magnet inside the float rises and falls with the water level to the corresponding height of the reed switch, the reed switch contacts are attracted under the action of the magnetic field, generating a switching trigger signal; the main float triggers the first three reed switches, and the backup float triggers the red limit warning reed switch at the highest position, forming a dual redundancy triggering mechanism. When the main float is entangled and stuck by weeds, branches and other debris and cannot rise, the backup float can still trigger the red warning when the water level continues to rise to 1.8m. The corresponding level of warning can be activated by triggering any float.

[0044] The water level gradient detection module uses a magnetostrictive level sensor, installed at the top of the guide rod. The rod is 2.5m long, with a measurement range of 0-2m, a measurement accuracy of ±1mm, a resolution of 0.1mm, and a sampling frequency of 1 time / minute. The sensor is connected to the main control board via an RS485 bus, continuously measuring the current water level in real time. The main control MCU calculates the rate of water level rise per unit time based on five consecutive sampling values. The calculation formula is as follows:

[0045]

[0046] Where h t h represents the current water level. t-5 The value is the water level 5 minutes ago, v is the rate of water level rise, denominator 5 is the time interval, and the unit is cm / min.

[0047] The cloud-based intelligent processing unit is deployed on an Alibaba Cloud ECS server, adopting a Spring Boot microservice architecture, including a device access module, a data processing module, a tiered early warning module, an automatic call module, and a data storage module. The main control board of the water level sensing trigger unit uses an STM32L431 low-power MCU, and establishes a TCP connection with the cloud through the Quectel BC95NB-IoT communication module. The communication protocol adopts the CoAP lightweight IoT protocol, and the data transmission uses DTLS encryption. Under normal conditions, the main control board is in STOP2 low-power mode, with a current consumption of only 12μA. It wakes up once every 24 hours to report heartbeat data and battery voltage data. When the reed switch is triggered or the water level rise rate exceeds the threshold, the main control board wakes up immediately, completes the connection registration with the base station within 10 seconds, and uploads data such as the trigger signal, real-time water level, and battery voltage to the cloud.

[0048] The cloud-based intelligent processing unit has four preset warning thresholds: a blue warning corresponds to a water level reaching 80% of the warning level (1.2m) and a rise rate of less than 1cm / min; a yellow warning corresponds to a water level reaching 90% of the warning level (1.35m) and a rise rate of less than 2cm / min; an orange warning corresponds to a water level reaching the warning level (1.5m); and a red warning is triggered when the water level exceeds the warning level (>1.5m) or the water level rises by more than 20cm within 10 minutes (rise rate>2cm / min). The graded warning module dynamically determines the warning level based on the uploaded water level value and the calculated rise rate, and automatically upgrades the warning level by one level when the rise rate exceeds the threshold.

[0049] The automatic calling module integrates Alibaba Cloud voice service. After an alert is triggered, it immediately dials the responsible person's phone number according to the preset contact priority order. Each contact can dial a maximum of 3 times. If the first call is not answered, it will automatically redial after 30 seconds. If it is not answered after 3 consecutive calls, it will automatically dial the next alternative responsible person's phone number. Up to 5 levels of contacts can be set. After the call is connected, a pre-recorded TTS voice alert message will be played automatically. The voice content is: "[Bridge and Culvert Water Level Alert] The water level of the bridge and culvert at K123+450 of XX National Highway has reached X meters, triggering a color X alert. Please take immediate action." At the same time, an alert SMS containing the same information and a link to the real-time data on site will be sent. All alert times, water level data, call records, and SMS sending status are automatically stored in the MySQL database and synchronized to OSS object storage for permanent storage, serving as the basis for subsequent disaster analysis and maintenance decisions.

[0050] The on-site warning unit adopts an integrated pole design, with a pole height of 6m, made of hot-dip galvanized steel pipe and a concrete foundation. Each pole integrates a traffic light warning module, an LED information display screen, a directional voice broadcast module, an infrared vehicle detection module, an automatic lifting barrier gate, and a video capture module. The traffic light warning module uses φ300mm LED traffic lights; a solid green light indicates normal passage, while a high-frequency flashing red light (2Hz) indicates prohibition. The red light has a brightness greater than 5000cd and is clearly visible at a distance of 100m under strong daylight. The LED information display screen uses a P10 outdoor high-brightness LED screen, measuring 1m × 0.5m, with a brightness greater than 6000cd / m². 2 When an alert is triggered, different content is displayed depending on the alert level: a yellow alert indicates that the water level is rising and you should pay attention; an orange alert indicates that the water level is high and you should proceed with caution; and a red alert indicates that the water level exceeds the standard and you should not proceed. The text is displayed in red font and scrolls.

[0051] The directional voice broadcast module uses a phased array directional loudspeaker with four elements, a rated power of 30W, and a sound pressure level greater than 110dB. Through phase control technology, the sound beam angle is controlled within a range of 30° horizontally and 15° vertically, playing warning messages only towards oncoming traffic. At a distance of 20m from the side of the loudspeaker, the sound pressure level is less than 55dB, preventing noise pollution to nearby residents. The infrared vehicle detection module uses an active infrared beam detector with a detection distance of 50m and an installation height of 1.2m. When a vehicle enters the 50m range, a directional voice broadcast is immediately triggered. Different warning levels play different content: a yellow warning announces rising water levels ahead, please slow down and observe before proceeding; an orange warning announces high water levels ahead, please proceed only after confirming safety; and a red warning announces excessive water levels ahead, prohibiting passage and requesting immediate U-turn. The voice message is repeated three times.

[0052] The automatic lifting barrier gate uses a straight-arm barrier gate driven by a DC brushless motor. The arm is 3.5m long and the lifting and lowering time is 3 seconds. When a red warning is triggered, it automatically lowers to physically block vehicles. The barrier arm is covered with red and white reflective film, providing a visibility distance of more than 200m at night. The barrier gate has an anti-smashing function; it will automatically raise the arm if a vehicle is encountered during the lowering process. The video capture module 36 uses a 2-megapixel network camera with a 6mm focal length and is equipped with an infrared fill light. The effective shooting distance at night is 50m. When a red warning is triggered, it automatically captures images of vehicles entering the warning area, taking one image every 2 seconds. At the same time, it starts recording 1080P video. The captured photos and video files are uploaded to the cloud storage in real time via a 4G network for a storage time of no less than 90 days.

[0053] The on-site warning unit communicates with the cloud via an EC204GCat.1 module with a communication delay of less than 1 second, ensuring that cloud commands can be quickly sent to on-site equipment. On-site equipment is connected via LoRa wireless networking, and the warning units at both ends of the bridge and culvert can achieve status synchronization, with one end triggering an alarm and the other end simultaneously activating an alarm.

[0054] The solar power unit includes a 20W monocrystalline silicon solar panel, a 12V / 20Ah lithium iron phosphate battery, and a power management module. The solar panel has a conversion efficiency greater than 22%, and the installation angle is set to 30° south based on the local latitude. The lithium iron phosphate battery has an operating temperature range of -20℃ to 60℃ and a cycle life greater than 2000 cycles. The power management module adopts MPPT maximum power point tracking charging management, with a charging efficiency greater than 95%, and also has overcharge, over-discharge, overcurrent, and short-circuit protection functions. The system has an overall low power consumption design, with an overall current consumption of less than 45μA in standby mode and an average current of less than 5mA in daily operation. Based on an average of 3.5 hours of sunshine per year in southern regions, the system can still operate normally even after 30 consecutive days of cloudy or rainy weather after a full charge, without requiring external mains power.

[0055] The emergency dispatch unit is deployed in the cloud and has a built-in bridge and culvert basic database and emergency personnel GIS database. The bridge and culvert basic database stores information such as the number, location, latitude and longitude, design water level, historical flood damage records, and surrounding detour routes of all monitored bridges and culverts. The emergency personnel GIS database stores the names, phone numbers, responsible areas, and real-time location information of all maintenance personnel and emergency rescue personnel. After an alert is triggered, the system automatically calculates the real-time distance and estimated arrival time of all online emergency personnel within a 10km radius of the bridge or culvert location via the Gaode Map API. Based on the principles of distance priority and responsibility matching, it automatically dispatches tasks to the two nearest emergency personnel. The task dispatch is conducted via the API. The system provides dual notifications via push notifications and SMS, including a precise navigation link to the bridge / culvert's location, current water level, warning level, standard handling procedures, and recommended detour routes. The standard handling procedures include: upon arrival at the scene, setting up warning signs, checking the status of the gate, dissuading vehicles from passing, inspecting the bridge piers for erosion, measuring the actual water level, reporting to higher authorities as needed, inspecting structural damage after the water recedes, and clearing the site to restore traffic. Emergency personnel report the handling progress and on-site photos in real time via the app. The system tracks the entire handling process until the on-site handling is completed, the water level drops below a safe level, and the warning is lifted only after administrator confirmation, forming a complete management loop.

[0056] The installation and usage process in this embodiment is as follows: First, a water level sensing trigger unit is installed on the upstream side of the bridge and culvert, a concrete anti-siltation base is poured, and the guide rod is vertically fixed next to the bridge pier; then, the foundation for the uprights is poured at both ends of the bridge and culvert, and an integrated on-site warning unit and a solar power supply unit are installed; finally, the bridge and culvert foundation information and emergency personnel information are entered into the cloud system, and system integration testing is conducted. Under normal conditions, the system is automatically on duty 24 hours a day without human intervention; after an alert is triggered, the entire process of notification, warning, and dispatch is automatically completed. Emergency personnel receive the notification and rush to the scene to handle the situation. After handling the situation, the alert is lifted by reporting via the APP.

[0057] This embodiment underwent 6 months of field trial operation and withstood 3 floods exceeding the warning level. The system's trigger accuracy was 100%, the false alarm rate was 0, the warning information delivery time was less than 10 seconds, and the average arrival time of emergency personnel was 18 minutes. Compared with the traditional manual patrol mode, the response speed was improved by 80%. During the period, no vehicle wading accidents occurred, and the application results were good.

[0058] Example 2: Simplified Application Example of Small Rural Bridges and Culverts

[0059] This embodiment is applied to small bridges and culverts on rural roads. The bridge and culvert span is 4m, the design warning water level is 1m, the daily traffic volume is small, and the budget is limited, so a simplified configuration scheme is adopted.

[0060] The difference from Embodiment 1 is that this embodiment simplifies some configurations. The water level sensing trigger unit only has a main float and a reed switch, corresponding to yellow, orange, and red three-level warnings. It does not have a spare float or a magnetostrictive continuous liquid level sensor, and only uses reed switches for switching triggering, thus reducing costs. The on-site warning unit does not have an automatic lifting gate and video capture module, but only retains traffic lights, LED screens, and directional voice broadcast functions. The solar power supply unit uses a 10W solar panel and a 12V / 10Ah lithium iron phosphate battery to meet the low power consumption requirements of the simplified configuration. The emergency dispatch unit only has two levels of contacts, does not enable the GIS automatic dispatch function, and only automatically notifies village road administrators and township maintenance personnel after an early warning.

[0061] The simplified solution in this embodiment costs only 40% of the standard configuration in Embodiment 1. Although the functions are simplified, the core functions of water level triggering, automatic telephone warning, and on-site sound and light warning are still retained. It can meet the basic safety warning needs of small bridges and culverts in rural areas and is suitable for large-scale promotion and application on rural roads in economically underdeveloped areas.

[0062] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0063] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0064] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A floating intelligent water level detection and early warning system for bridges and culverts, comprising a water level sensing triggering unit, a cloud-based intelligent processing unit, an on-site warning unit, and an emergency dispatch unit, characterized in that... ； The water level sensing triggering unit includes a vertical guide rod, a main float, a spare float, a magnetic coupling triggering mechanism, and a water level gradient detection module; The main float and the backup float rise and fall with the water level along the vertical guide rod. The magnetic coupling triggering mechanism adopts a non-contact magnetic induction design and triggers an early warning signal when the water level reaches a preset threshold. The water level gradient detection module is used to collect water level change rate data in real time. The cloud-based intelligent processing unit and the water level sensing triggering unit are connected via an NB-IoT network. The unit is used to receive trigger signals and water level data, execute hierarchical early warning logic, automatically push voice calls and SMS warnings to preset responsible persons, and store the early warning data in the cloud. The on-site warning unit is set at the entrances at both ends of the bridge and is wirelessly connected to the cloud-based intelligent processing unit. It includes a traffic light warning module, an LED information display screen, a directional voice broadcast module, and an infrared vehicle detection module, which are used to automatically warn passing vehicles and pedestrians when the warning is triggered. The emergency dispatch unit is connected to the cloud-based intelligent processing platform, which is used to automatically dispatch the nearest emergency personnel based on GIS location information and generate standardized emergency response process guidelines.

2. The bridge and culvert floating intelligent water level detection and early warning system according to claim 1, characterized in that, The magnetic coupling triggering mechanism includes a permanent magnet inside the float and multiple reed switches at different heights on the guide rod; the reed switches are sealed with epoxy resin and completely isolated from the water; the main float and the backup float are spaced vertically to form a dual-redundant triggering mechanism, and an early warning can be activated by triggering any float.

3. The bridge and culvert floating intelligent water level detection and early warning system according to claim 2, characterized in that, The vertical guide rod has a self-cleaning coating on its surface and an anti-sludge base at its bottom; the main float and the spare float are made of high-density polyethylene corrosion-resistant material and filled with closed-cell foam, and a polytetrafluoroethylene wear-resistant guide ring is provided between the float and the guide rod.

4. The bridge and culvert floating intelligent water level detection and early warning system according to claim 1, characterized in that, The water level gradient detection module includes a magnetostrictive liquid level sensor with a sampling frequency of not less than 1 time / minute, used to calculate the water level rise rate; the cloud-based intelligent processing unit has four preset warning thresholds: blue warning, yellow warning, orange warning and red warning, and dynamically adjusts the warning level according to the current water level height and water level rise rate.

5. The bridge and culvert floating intelligent water level detection and early warning system according to claim 1, characterized in that, The cloud-based intelligent processing unit includes an automatic calling module. After an early warning is triggered, the automatic calling module automatically dials the phone number of a preset responsible person. If the first call is not answered, it will automatically redial after 30 seconds. If the call is not answered after three consecutive attempts, it will automatically dial the phone number of an alternative responsible person. After the call is connected, it plays a pre-recorded voice warning message, which includes the location of the bridge and culvert, the current water level, and the warning level.

6. The bridge and culvert floating intelligent water level detection and early warning system according to claim 1, characterized in that, The directional voice broadcast module uses a phased array directional speaker to play warning voice messages only in the direction of oncoming vehicles, thus avoiding noise pollution to the surrounding environment. When the infrared vehicle detection module detects a vehicle approaching within 50 meters, it automatically triggers the directional voice broadcast, and the broadcast content is dynamically adjusted according to the warning level.

7. The bridge and culvert floating intelligent water level detection and early warning system according to claim 1, characterized in that, The on-site warning unit also includes an automatic lifting barrier gate and a video capture module; when a red alert is triggered, the automatic lifting barrier gate drops to physically block vehicles, and the video capture module automatically captures and records evidence of vehicles entering the warning area, with the captured photos uploaded to the cloud for storage in real time.

8. The bridge and culvert floating intelligent water level detection and early warning system according to claim 1, characterized in that, The system also includes a solar power supply unit, comprising a monocrystalline silicon solar panel, a lithium iron phosphate battery, and a power management module; the power management module adopts a low-power design, with a standby power consumption of no more than 50μA, and can support the system to work normally for no less than 30 days during continuous cloudy and rainy days.

9. The bridge and culvert floating intelligent water level detection and early warning system according to claim 1, characterized in that, The emergency dispatch unit has a built-in bridge and culvert basic database and emergency personnel GIS database. After the warning is triggered, it automatically calculates the real-time distance and arrival time of the surrounding emergency personnel, automatically dispatches orders according to the distance priority principle, and pushes standardized handling guidelines containing the location of bridges and culverts, risk level, handling procedures, and surrounding detour routes to the dispatching personnel.

10. The bridge and culvert floating intelligent water level detection and early warning system according to claim 1, characterized in that, It also includes an early warning method applied to the system as described in any one of claims 1-9, comprising the following steps: S1. Daily monitoring: The water level sensing trigger unit collects water level data and water level change rate in real time, and reports the data to the cloud periodically through the NB-IoT network. The system is in a low-power standby state. S2. Warning Trigger: When the water level rises and triggers the magnetic coupling trigger mechanism, or when the rate of water level rise exceeds the preset threshold, the system immediately wakes up from standby mode and sends a trigger signal and real-time water level data to the cloud intelligent processing unit. S3, Tiered Early Warning: The cloud-based intelligent processing unit determines the early warning level based on the current water level height and the rate of rise, and initiates the corresponding level of early warning process; S4. Multi-channel notification: Automatically makes voice calls and sends text messages to the responsible person, while simultaneously issuing control commands to the on-site warning unit; S5. On-site warning: The on-site warning unit activates a flashing red light, displays warning information on the LED screen, and broadcasts directional voice messages. When a red warning is issued, the gate automatically closes to physically intercept the vehicle and captures evidence. S6. Emergency Dispatch: Based on GIS, automatically dispatch the nearest emergency personnel, push standardized handling guidelines, track the handling progress, and continue until the warning is lifted.

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