Portal crane track guard

Abstract

The present application relates to the technical field of track protection, in particular to a gantry crane track protection device, comprising a plurality of multilayer composite pad bodies arranged above the track, a plurality of independently arranged height-adjustable bases and a controller. The pad body is embedded with a strain sensor array and an inclination sensor, and each base is provided with a height adjustment mechanism and a pressure sensor. The controller receives multi-source data of pressure, strain and inclination, and performs closed-loop leveling with the goal of balancing the pressure of each base. Through fusion analysis, it is determined whether the unevenness is caused by foundation settlement or pad body deformation, and different leveling strategies are executed accordingly. The present application realizes accurate diagnosis and self-adaptive leveling of the unevenness source of the track pad, avoids secondary damage caused by blind adjustment, and significantly improves the intelligence and safety of the track protection device in a radioactive environment.

Description

Technical Field

[0001] This invention relates to the field of track protection technology, and in particular to a track protection device for gantry cranes. Background Technology

[0002] In radioactive waste disposal sites, gantry crane track pads are used to protect the tracks from heavy vehicles. Existing technology uses lightweight, high-strength materials such as ultra-high molecular weight polyethylene to produce lightweight pads with a self-weight of ≤10kg and a load-bearing capacity of ≥40T. However, the foundation of disposal sites often experiences uneven settlement due to unfavorable geological conditions such as soft soil and fill, causing the pads to tilt. When heavy-duty trucks pass at high speeds, the lower side tires generate impact loads several times greater than the static load, accelerating foundation settlement and increasing the risk of vehicle skidding. To solve this problem, existing technology proposes an adjustable base scheme. This scheme uses pressure sensors to detect the load on each base and automatically adjusts the base height to achieve pressure balance and level the pads. However, this scheme has a drawback: it can only detect unevenness of the pads but cannot distinguish whether the root cause of the unevenness is foundation settlement or plastic deformation of the pad itself. When the foundation settles, adjusting the height of the base can effectively solve the problem; however, when the base plate itself has undergone permanent deformation due to long-term overloading, continuing to adjust the base will not only fail to eliminate the bending of the base plate itself, but will also cause the stress on the base plate to deteriorate due to the change in the position of the support point, accelerate its damage, or even cause sudden breakage, resulting in serious safety accidents. Summary of the Invention

[0003] In view of this, the purpose of this invention is to provide a gantry crane track protection device to solve the problem that the current method can only detect unevenness of the pad, but cannot distinguish whether the root cause of the unevenness is foundation settlement or plastic deformation of the pad itself.

[0004] To achieve the above objectives, a gantry crane track protection device includes: a base plate body for straddling the track, through which vehicle tires pass; multiple height-adjustable bases independently disposed between the bottom surface of the base plate body and the foundation, each base including a height adjustment mechanism and a pressure sensor; and a controller that receives signals from all pressure sensors and, with the goal of balancing the pressure borne by each base, controls the height adjustment mechanism to adjust the height of each base; wherein the base plate body is a multi-layer composite structure, internally embedded with a strain sensor array and an inclination sensor, and the controller also receives signals from the strain sensor array and the inclination sensor, and, based on the multi-source data fusion results from the pressure sensor, strain sensor array, and inclination sensor, determines whether the unevenness is caused by foundation settlement or deformation of the base plate body, and selects different leveling strategies based on the determination results.

[0005] Optionally, the multi-layer composite structure of the pad body includes: an upper layer of high wear-resistant elastomer that directly bears the impact of the tire; a middle layer of ultra-high molecular weight polyethylene as the main load-bearing layer; and a bottom layer of carbon fiber reinforced composite material, in which the strain sensor array and the tilt sensor are embedded. The three layers are combined through a hot-pressing composite process, so that when the pad body is subjected to heavy loads, the upper layer undergoes elastic compression to absorb the impact energy, while the bottom layer remains flat to ensure uniform pressure transmission.

[0006] Optionally, the base has a positioning boss on its top, and the bottom surface of the pad body has a positioning recess that mates with the positioning boss. The positioning boss and the positioning recess form a ball joint coupling connection, which restricts the horizontal displacement of the pad body while allowing small-angle swing. The pressure sensor is integrated on the top of the positioning boss and directly contacts the bottom surface of the pad body. The side of the base is also provided with a contact displacement sensor for measuring the relative displacement between the positioning boss and the positioning recess. This relative displacement data serves as the basis for determining whether the pad body is detached or warped.

[0007] Optionally, the controller has a built-in fault root cause diagnosis module, which executes the following judgment logic: when the pressure distribution of each base is uneven, the relative displacement data are all close to zero, and the strain sensor array displays a bending mode, it is diagnosed that the pad body has undergone plastic deformation, and the controller issues an alarm to replace the pad body; when the pressure of a base on a certain side decreases, the corresponding relative displacement increases, and the tilt sensor shows that the pad body is tilted to that side, it is diagnosed that the foundation is in a local settlement, and the controller only adjusts the height of the base on that side; when the pressure of all bases decreases evenly, the relative displacement is zero, and the strain sensor array is normal, it is diagnosed that the foundation is in an overall settlement, and the controller raises all bases simultaneously; when the strain sensor array shows local strain abnormality, the corresponding base pressure is abnormally low but the relative displacement is zero, it is diagnosed that the pad body is partially damaged, and the controller issues a shutdown alarm.

[0008] Optionally, the controller can also determine the degree of plastic deformation of the pad body based on the residual strain data of the strain sensor array. When the residual strain exceeds a preset threshold, the controller locks the height adjustment function of all bases and forces the pad body to be replaced before operation can be resumed.

[0009] Optionally, the controller includes a vehicle passage detection module, which identifies the vehicle passage status by monitoring the rate of change of pressure sensor signals: when the rate of change of pressure exceeds a preset threshold, it is determined that a vehicle is passing through, the controller suspends all height adjustment actions, and marks the currently collected data as dynamic data and does not use it; when the rate of change of pressure returns to below the threshold for a preset time, the controller resumes the adjustment function and collects static data for leveling calculation.

[0010] Optionally, the height adjustment mechanism is an electric screw jack, each equipped with an independent motor driver; the controller adopts a closed-loop proportional-integral-derivative (PID) control algorithm, takes the deviation between the pressure of each base and the average pressure as input, outputs the adjustment amount of each electric screw jack, and the single adjustment step does not exceed 2mm, and the adjustment speed does not exceed 1mm / s.

[0011] Optionally, a wear-resistant metal gasket is embedded in the positioning recess on the bottom surface of the pad body, and a self-lubricating coating is applied to the surface of the positioning boss on the top of the base. An elastic sealing ring is provided between the positioning boss and the positioning recess to prevent radioactive dust or water from entering the coupling interface.

[0012] Optionally, a remote monitoring module is also included. This module transmits the pressure data of each base, the strain data and tilt angle data of the pad body, and the fault diagnosis results to the central monitoring room in real time via wireless communication. After receiving an alarm to replace the pad body, the remote monitoring module automatically generates a maintenance work order containing the fault location, fault type, and recommended handling solution.

[0013] Optionally, the controller also has a fail-safe mode: when the strain sensor array or tilt sensor fails, the controller switches to a simplified leveling mode that relies solely on the pressure sensor; when some pressure sensors fail, the controller estimates the pressure value of the failed base based on the data from the remaining effective pressure sensors and tilt sensors, and maintains the leveling function; when all sensors fail, the controller maintains the current base height unchanged and issues an emergency alarm through the remote monitoring module, and the device operates in a purely mechanical support mode.

[0014] The controller periodically collects data from the pressure sensors of each base, the strain sensor array inside the pad body, and the tilt sensor. It calculates the average pressure of all bases and compares the pressure of each base with the average to obtain the deviation. When the deviation exceeds a preset threshold, the controller determines that the pad is in an uneven state. Then, by analyzing the spatial distribution pattern of the strain sensor array and the directional data of the tilt sensor, if the strain array shows that the pad body has significant bending deformation and the tilt direction matches the strain gradient direction, it is diagnosed as plastic deformation of the pad body. The controller only issues an alarm and does not adjust the base height to avoid aggravating damage. If the strain array shows that the pad body has no obvious bending deformation but the pressure distribution is uneven, it is diagnosed as uneven settlement of the foundation. The controller drives the base with low pressure to rise or the base with high pressure to fall, so that the pressure of each base is restored to equilibrium, thereby achieving a level pad.

[0015] By integrating multi-source data from pressure sensors, strain sensor arrays, and tilt sensors, accurate diagnosis of the root causes of unevenness is achieved. This enables the differentiation between foundation settlement and deformation of the base plate itself, avoiding secondary damage caused by blindly adjusting the base when the base plate is already damaged. At the same time, it realizes active, closed-loop control of automatic leveling without manual intervention, significantly improving the adaptability and safety of the track protection device in a radioactive environment. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only for this invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the protective device according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the displacement sensor position according to an embodiment of the present invention.

[0018] The numbers on the map are: 1. Pad body; 2. Base; 3. Track; 4. Positioning boss; 5. Displacement sensor. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.

[0020] It should be noted that, unless otherwise defined, the technical or scientific terms used in this invention should have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0021] like Figure 1As shown, a gantry crane track protection device includes: a base plate body 1, used to span over the track 3, with vehicle tires passing over the surface of the base plate body 1; multiple adjustable height bases 2, independently set between the bottom surface of the base plate body 1 and the foundation, each base 2 including a height adjustment mechanism and a pressure sensor; a controller, receiving signals from all pressure sensors and controlling the height adjustment mechanism to adjust the height of each base 2 with the goal of balancing the pressure borne by each base 2; wherein, the base plate body 1 is a multi-layer composite structure, with a strain sensor array and an inclination sensor embedded inside, the controller also receiving signals from the strain sensor array and the inclination sensor, and judging whether the root cause of unevenness is foundation settlement or deformation of the base plate body 1 based on the multi-source data fusion results of the pressure sensor, strain sensor array and inclination sensor, and selecting different leveling strategies according to the judgment results.

[0022] The pad body 1 is a rectangular flat plate structure, with its length direction aligned with the extension direction of the track 3 and its width spanning both left and right tracks 3, employing a multi-layer composite structure. Multiple adjustable height bases 2 are evenly arranged along the transverse sides and longitudinal ends of the bottom surface of the pad body 1. Each base 2 includes a servo motor-driven screw jack as a height adjustment mechanism, and a thin-film pressure sensor mounted on the top of the base 2 in contact with the pad body 1. The controller is a programmable logic controller or an embedded microcontroller, electrically connected to the pressure sensor of each base 2, the strain sensor array embedded in the pad body 1, and the tilt sensor. The controller has a built-in pressure equalization algorithm and fault diagnosis model. By collecting multi-source sensor data in real time, it calculates the deviation between the pressure of each base 2 and the average pressure, and drives the height adjustment mechanism of the corresponding base 2 to raise and lower until the pressure deviation of all base 2 is less than the preset threshold. At the same time, the controller fuses and compares the distribution data of the strain sensor array with the tilt angle data. When it detects that the pad body 1 has a bending strain mode and the tilt angle direction is consistent with the strain distribution, it is determined that the pad body 1 is deformed. When it detects that the pressure distribution is uneven but the strain of the pad body 1 is normal, it is determined that the foundation is settled, and the corresponding leveling strategy is executed respectively.

[0023] The controller periodically collects data from the pressure sensors of each base 2, the strain sensor array inside the pad body 1, and the tilt sensor. It calculates the average pressure of all base 2 and compares the pressure of each base 2 with the average to obtain the deviation. When the deviation exceeds a preset threshold, the controller determines that the pad is in an uneven state. Then, by analyzing the spatial distribution pattern of the strain sensor array and the directional data of the tilt sensor, if the strain array shows that the pad body 1 has significant bending deformation and the tilt direction matches the strain gradient direction, it is diagnosed as plastic deformation of the pad body 1. The controller only issues an alarm and does not adjust the height of the base 2 to avoid aggravating damage. If the strain array shows that the pad body 1 has no obvious bending deformation but the pressure distribution is uneven, it is diagnosed as uneven settlement of the foundation. The controller drives the base 2 with low pressure to rise or the base 2 with high pressure to fall, so that the pressure of each base 2 is restored to equilibrium, thereby achieving a level pad.

[0024] By integrating multi-source data from pressure sensors, strain sensor arrays, and tilt sensors, accurate diagnosis of the root causes of unevenness is achieved. This enables the differentiation between foundation settlement and deformation of the base plate 1, avoiding secondary damage caused by blindly adjusting the base 2 when the base plate is already damaged. At the same time, it realizes active, closed-loop control of automatic leveling without manual intervention, significantly improving the adaptability and safety of the track 3 protection device in a radioactive environment.

[0025] In some embodiments, the multi-layer composite structure of the pad body 1 includes: an upper layer of high wear-resistant elastomer that directly bears the impact of the tire; a middle layer of ultra-high molecular weight polyethylene as the main load-bearing layer; and a bottom layer of carbon fiber reinforced composite material, in which the strain sensor array and the tilt sensor are embedded. The three layers are combined by a hot-pressing composite process, so that when the pad body 1 is subjected to heavy loads, the upper layer undergoes elastic compression to absorb the impact energy, while the bottom layer remains flat to ensure uniform pressure transmission.

[0026] The upper layer is a high-wear-resistant polyurethane elastomer layer, 3-8mm thick, with a Shore hardness of A85-95. It directly contacts the vehicle tires, utilizing its high elasticity and wear resistance to absorb tire impact and protect the underlying structure. The middle layer is an ultra-high molecular weight polyethylene (UHMWPE) main load-bearing layer, 25-35mm thick, with a molecular weight of not less than 3 million. It bears the main static and dynamic loads of the vehicle, utilizing its lightweight and high-strength characteristics to ensure the overall weight of the pad does not exceed 10kg and its load-bearing capacity is not less than 40T. The bottom layer is a carbon fiber reinforced composite material layer, with a thickness of... The thickness is 3-6mm, and it is made of unidirectional or woven carbon fiber prepreg and epoxy resin composite, which has extremely high flexural modulus and flexural strength. The strain sensor array is fixed to the inside or surface of the bottom layer by pre-embedding or surface mounting. The three-layer structure is composited and cured in one go under high temperature and high pressure by autoclave or hot press to form a gapless integral structure between the layers. When the upper layer is elastically compressed and deformed, the load is evenly transferred to the middle layer, and then distributed from the middle layer to the bottom layer. The bottom layer maintains a flat state due to its high rigidity, ensuring that the contact pressure with each base 2 is evenly distributed.

[0027] When a heavy-duty vehicle tire rolls over the upper surface of the pad, the upper high-wear-resistant elastomer layer first undergoes elastic compression, converting the point contact load into a surface contact load and absorbing some of the impact energy. The compressed load is then transferred to the middle ultra-high molecular weight polyethylene layer. This layer utilizes its high toughness and high strength to disperse the load along the planar direction, avoiding stress concentration. Finally, the load is transferred to the bottom carbon fiber composite layer. Because the carbon fiber composite material has extremely high bending stiffness, it hardly undergoes bending deformation when bearing load, thus maintaining uniform contact between the bottom surface of the pad and the top surface of each base 2. This ensures that the pressure borne by each base 2 is linearly proportional to the load on the pad, providing an accurate mechanical basis for pressure equalization and leveling.

[0028] The three-layer composite structure achieves a functional gradient design of "flexible on top and rigid on the bottom". The upper elastic layer effectively buffers tire impact and reduces vehicle bumps and foundation impact loads. The middle lightweight and high-strength layer ensures that the overall self-weight meets the standard while meeting the heavy load requirements. The bottom high-rigidity layer ensures that the bottom surface of the pad always remains flat, so that the pressure sensor measurement value is highly consistent with the actual load distribution, thereby improving the accuracy and reliability of leveling control.

[0029] In some embodiments, the base 2 has a positioning boss 4 on its top, and the bottom surface of the pad body 1 has a positioning recess that mates with the positioning boss 4. The positioning boss 4 and the positioning recess form a ball joint coupling connection, which restricts the horizontal displacement of the pad body 1 while allowing small-angle swing. The pressure sensor is integrated on the top of the positioning boss 4 and directly contacts the bottom surface of the pad body 1. The side of the base 2 is also provided with a contact displacement sensor 5, which is used to measure the relative displacement between the positioning boss 4 and the positioning recess. This relative displacement data serves as the basis for determining whether the pad body 1 is detached or warped.

[0030] like Figure 2 As shown, a cylindrical positioning boss 4 is provided at the center of the top of the base 2. The upper surface of the boss is spherical or has a spherical pad. The boss has a diameter of 20-40mm and a height of 10-20mm. The bottom surface of the pad body 1 has a circular positioning recess at a position corresponding to each base 2. The depth of the recess matches the height of the boss. The bottom of the recess is also spherical, forming a ball-joint fit with the spherical surface of the boss, allowing the pad to swing freely within a certain angle range (±3°) without horizontal slippage. The pressure sensor is a spoke-type or thin-film sensor, embedded in the center of the top of the positioning boss 4. The upper surface of the sensor is flush with or slightly higher than the spherical surface of the boss, directly contacting the pad. The bottom surface of the positioning recess; a displacement sensor 5 is fixedly installed on the side of the base 2. It can be a contact sensor. The sensor is a spring-reset linear displacement sensor 5. The probe head is hemispherical. Under the action of the pre-tightening spring, it is always in close contact with the bottom surface of the pad (10-20mm outside the positioning recess). A dustproof sealing ring is provided between the probe and the base 2. The displacement sensor 5 measures the extension length of the probe relative to the housing of the base 2. The relative vertical displacement between the positioning boss 4 and the positioning recess is obtained by subtracting the initial calibration value from this length. When the displacement value is zero, it means that the pad and the base 2 are in close contact. When it is greater than zero, it means that there is a gap between the pad and the base 2.

[0031] When the pad is placed horizontally and all bases 2 are at the same height, all positioning protrusions 4 and positioning recesses are in close contact. The pressure sensor outputs the actual bearing pressure of each base 2, and the displacement sensor 5 outputs zero. When uneven settlement of the foundation causes a certain base 2 to sink relatively, a gap appears between the positioning protrusion 4 of that base 2 and the positioning recess of the pad. Under the action of its own weight and vehicle load, the pad is still in contact with other bases 2. This gap causes the probe of the displacement sensor 5 to pop up and output a positive displacement value. At the same time, the output value of the pressure sensor of that base 2 decreases significantly. The controller confirms the foundation settlement by using the positive displacement signal of the displacement sensor 5 and the decreasing signal of the pressure sensor, and drives the base 2 to rise until the displacement sensor 5 returns to zero and the pressure is restored to equilibrium. When the pad body 1 undergoes plastic bending deformation, the bottom surface of the pad locally warps up. The displacement sensor 5 also outputs a positive displacement. However, at this time, the output value of the pressure sensor may not decrease significantly or may show an abnormal distribution. Combined with the bending strain mode of the strain sensor array, the controller can distinguish the pad deformation from the foundation settlement.

[0032] The ball-joint boss-recess coupling structure allows the pad to swing adaptively within a small angle range while accurately positioning the pad, avoiding stress concentration caused by rigid connection; the pressure sensor integrated on the top of the boss directly measures the actual contact pressure between the pad and the base 2, eliminating measurement errors caused by intermediate force transmission components; the independent contact displacement sensor 5 provides direct measurement of the free state of each support point, forming a redundant verification with the pressure sensor, which greatly improves the accuracy of fault diagnosis and the robustness of leveling control.

[0033] In some embodiments, the controller has a built-in fault root cause diagnosis module, which executes the following judgment logic: when the pressure distribution of each base 2 is uneven, the relative displacement data are all close to zero, and the strain sensor array shows a bending mode, it is diagnosed that the pad body 1 has undergone plastic deformation, and the controller issues an alarm to replace the pad body 1; when the pressure of a certain base 2 decreases, the corresponding relative displacement increases, and the tilt sensor shows that the pad body 1 tilts to that side, it is diagnosed that the foundation is in a local settlement, and the controller only adjusts the height of the base 2 on that side; when the pressure of all base 2 decreases evenly, the relative displacement is zero, and the strain sensor array is normal, it is diagnosed that the foundation is in an overall settlement, and the controller raises all base 2 simultaneously; when the strain sensor array shows a local strain abnormality, the pressure of the corresponding base 2 is abnormally low but the relative displacement is zero, it is diagnosed that the pad body 1 is partially damaged, and the controller issues a shutdown alarm.

[0034] The controller integrates a fault root cause diagnosis module based on decision tree or fuzzy logic. This module uses the pressure sensor signals of each base 2, the displacement sensor signals of each base 2, the strain distribution data of the strain sensor array of the pad body 1, and the tilt angle data of the tilt sensor as input variables. It outputs diagnostic conclusions through preset multi-level judgment rules. The diagnostic rules include: the first level judges whether the relative displacement of each base 2 is close to zero. If so, it enters the pad deformation judgment branch; otherwise, it enters the foundation settlement judgment branch. In the pad deformation judgment branch, it further compares whether the strain sensor array shows a bending strain mode consistent with the tilt angle direction. If so, it is diagnosed as plastic deformation of the pad body 1. In the foundation settlement judgment branch, it is diagnosed as local settlement or overall settlement based on whether the position of the base 2 with the pressure drop is consistent with the tilt angle direction. When the strain array shows an abnormal increase in the strain value in a local area and the corresponding base 2 pressure is abnormally reduced but the displacement is zero, it is diagnosed as local damage to the pad body 1. Each diagnostic conclusion generates different control commands and alarm signals.

[0035] The controller collects all sensor data at fixed intervals and stores it in a cache. First, it extracts the values ​​of displacement sensors 5 for each base 2. If all displacement values ​​are less than the preset contact threshold (e.g., 0.1 mm), it is determined that the pad is in contact with all bases 2. If the strain sensor array detects residual bending strain in the pad and the tilt sensor shows that the tilt direction of the pad matches the strain gradient direction, it is diagnosed that the pad body 1 has undergone plastic deformation. The controller issues a pad replacement alarm and locks the leveling function. If the displacement values ​​are all close to zero but the strain array is normal, it is determined that the foundation is under overall settlement. The controller raises all bases 2 simultaneously. If the displacement value of a certain base 2 is significantly greater than zero and the pressure on the corresponding side decreases, and the tilt sensor shows that the pad is tilted to that side, it is diagnosed that the foundation is under local settlement. The controller only adjusts the base 2 on that side. If the strain array shows an abnormal increase in local strain and the displacement of the corresponding base 2 is zero but the pressure is abnormally low, it is determined that the pad is partially damaged. The controller issues an emergency stop alarm.

[0036] Through multi-level fusion judgment logic, it is possible to accurately distinguish different fault types such as foundation settlement, pad deformation, and pad damage, avoiding misjudgment caused by insufficient information from a single sensor. This allows the leveling strategy to "treat the symptoms" and automatically compensate for foundation settlement and promptly alarm and shut down when the pad is damaged, effectively preventing the fault from escalating and safety accidents from occurring.

[0037] In some embodiments, the controller also determines the degree of plastic deformation of the pad body 1 based on the residual strain data of the strain sensor array. When the residual strain exceeds a preset threshold, the controller locks the height adjustment function of all bases 2 and forces the pad body 1 to be replaced before operation can be resumed.

[0038] The controller collects readings from the strain sensor array under no-load conditions after each vehicle passes or during periodic inspections. These readings are compared with the initial calibration values ​​to calculate the residual strain at each measuring point. The controller has multiple preset residual strain thresholds: the first threshold is 50% of the material's yield strain, and the second threshold is 80% of the material's yield strain. When the residual strain at any measuring point exceeds the first threshold but not the second threshold, the controller issues a warning signal, prompting maintenance personnel to monitor the pad's condition. When the residual strain at any measuring point exceeds the second threshold, the controller determines that the pad has undergone irreversible plastic deformation and its load-bearing capacity has decreased. It immediately locks all height adjustment mechanisms of the base 2, prohibiting any further leveling actions, and forcibly requires the replacement of the pad body 1 via audible and visual alarms and a remote communication module. Before replacement and recalibration are completed, the controller refuses to execute any height adjustment commands.

[0039] The controller periodically collects the output value of the strain sensor array under no-load conditions, subtracts the initial calibration value to obtain the residual strain distribution. When the residual strain exceeds the preset second-level threshold, it indicates that the ultra-high molecular weight polyethylene in the middle layer of the pad has yielded, and its internal microstructure has suffered irreversible damage. Continued load-bearing may lead to sudden fracture. At this time, the controller cuts off the drive power of all height adjustment mechanisms of base 2 through hardware interlock circuit, locking the height of base 2 in the current state. At the same time, it sends a forced alarm message to the central monitoring room containing the pad number, residual strain value, and recommended replacement period. The controller will only resume the leveling function after manual confirmation of replacement of the new pad and recalibration of the zero point.

[0040] By monitoring the residual strain of the pad in real time and setting graded thresholds, online assessment and early warning of the pad's fatigue life are realized. The leveling function is forcibly locked and the pad is forcibly replaced before it reaches the plastic deformation limit, which completely avoids safety accidents caused by sudden breakage of the pad. At the same time, it prevents misoperation and secondary damage caused by continuing to adjust the base 2 when the pad is damaged.

[0041] In some embodiments, the controller includes a vehicle passage detection module, which identifies the vehicle passage status by monitoring the rate of change of pressure sensor signals: when the rate of change of pressure exceeds a preset threshold, it is determined that a vehicle is passing through, the controller suspends all height adjustment actions, and marks the currently collected data as dynamic data and does not use it; when the rate of change of pressure returns to below the threshold for a preset time, the controller resumes the adjustment function and collects static data for leveling calculation.

[0042] The vehicle passage detection module is built into the controller and identifies vehicles by monitoring the rate of change of the pressure sensor signals of each base 2 in real time. The controller continuously collects pressure signals at a sampling rate of not less than 100Hz, calculates the rate of change of pressure ΔP / Δt for each sampling interval, and sets a dynamic threshold (e.g., 50kN / s). When the absolute value of the rate of change of pressure of any base 2 exceeds the threshold, the controller determines that a vehicle is passing and immediately triggers the vehicle passage flag. During the validity period of the vehicle passage flag, the controller suspends the drive output of all height adjustment mechanisms to ensure that the adjustment action is not performed during dynamic loading. At the same time, the controller marks all sensor data in the current collection cycle as "dynamic data" and does not participate in the leveling calculation. When the rate of change of pressure of all base 2 is continuously lower than the threshold for more than a preset time (e.g., 3 seconds), the controller clears the vehicle passage flag and resumes the data collection and leveling calculation functions.

[0043] When no vehicles are passing, the pressure sensor readings of each base 2 remain stable, with a rate of change close to zero. When a heavy-duty truck drives onto the platform, the wheels successively crush the area above each base 2, causing the pressure of the crushed base 2 to rise sharply from a static value to a peak value within milliseconds. The rate of pressure change far exceeds the preset dynamic threshold. After the controller detects this change, it immediately sets the vehicle passage sign. During the validity period of the sign, the controller ignores all pressure deviation calculations and does not send any adjustment commands to the height adjustment mechanism. At the same time, it stores the collected data in a dedicated buffer area but does not participate in the leveling algorithm. After the vehicle has completely passed and the pressure of all base 2 has returned to stability and remained stable for a preset time, the controller clears the sign and restarts the normal leveling process.

[0044] Automatic vehicle passage identification is achieved through pressure change rate detection, which effectively avoids malfunctions and adjustment oscillations caused by height adjustment during vehicle dynamic loading. This ensures that leveling control is executed only under stable static conditions. At the same time, the separate processing of dynamic and static data ensures the accuracy of leveling calculations and significantly improves the control stability of the system.

[0045] In some embodiments, the height adjustment mechanism is an electric screw jack, each electric screw jack is equipped with an independent motor driver; the controller adopts a closed-loop proportional-integral-derivative (PID) control algorithm, takes the deviation between the pressure of each base 2 and the average pressure as input, outputs the adjustment amount of each electric screw jack, and the single adjustment step does not exceed 2mm, and the adjustment speed does not exceed 1mm / s.

[0046] The electric screw jack consists of a DC brushless motor, a reduction gearbox, a trapezoidal or ball screw, and a guide sleeve. Each electric screw jack is equipped with an independent motor driver, which has built-in current feedback and position feedback interfaces. The controller uses an incremental PID control algorithm, taking the deviation between the pressure of each base 2 and the current average pressure of all bases 2 as the control error, to calculate the target adjustment amount of each base 2. The controller divides the target adjustment amount by the preset single adjustment step size (2mm) to obtain the adjustment step number, and outputs pulse signals to the motor driver step by step. Each pulse output corresponds to the motor rotating a fixed angle, causing the screw to rise or fall by 0.1mm. 20 consecutive pulses are output to complete one 2mm adjustment step. During the adjustment process, the controller reads the pressure sensor feedback value in real time. If the error decreases after adjustment, the adjustment continues in the same direction; if the error increases, the adjustment reverses. The output current of the motor driver is limited to within the rated value, and the adjustment speed is controlled below 1mm / s by the pulse frequency to ensure a smooth adjustment process.

[0047] The controller calculates the average pressure of each base 2 at a fixed period (e.g., 1 second). For each base 2, the pressure deviation is substituted into the PID controller to obtain the height correction amount ΔH. If the absolute value of ΔH is less than 2mm, no adjustment is made. If it is greater than or equal to 2mm, 2mm is taken as the single adjustment step size and the adjustment direction is determined. The controller sends a specified number of pulse signals to the corresponding motor driver. The driver controls the motor to rotate and drives the lead screw to lift and lower, and the height of the base 2 changes accordingly. The pressure sensor provides real-time feedback on the adjusted pressure value. The controller decides whether to continue adjusting based on the new pressure deviation until the pressure deviation of all base 2 is less than the preset allowable error range. The entire adjustment process adopts a small step size and low speed to avoid the pad shaking or overshooting caused by adjusting too quickly.

[0048] By adopting a step-by-step adjustment strategy with small step size (2mm) and low speed (1mm / s) combined with PID closed-loop control, the height of base 2 is adjusted precisely and smoothly, avoiding the impact on the pad and secondary tilting that may be caused by large-scale rapid adjustment. At the same time, the independent motor driver and current limiting design ensure the independence and safety of the adjustment of each base 2.

[0049] Wear-resistant metal gaskets are embedded in the positioning recesses on the bottom surface of the pad body 1. The positioning boss 4 on the top of the base 2 is coated with a self-lubricating coating, and an elastic sealing ring is provided between the positioning boss 4 and the positioning recesses to prevent radioactive dust or water from entering the coupling interface.

[0050] The wear-resistant metal gasket embedded in the positioning recess is made of stainless steel or hard alloy, with a thickness of 1-2 mm. It is fixed to the inner wall of the recess by interference fit or bonding, and the surface of the gasket is polished. The self-lubricating coating on the surface of the positioning boss 4 is a solid lubricating coating of polytetrafluoroethylene (PTFE) or molybdenum disulfide (MoS2) with a thickness of 10-50 μm. It is attached to the surface of the boss by spraying or sintering. The elastic sealing ring is a silicone rubber or fluororubber O-ring, which is installed in the annular groove between the root of the positioning boss 4 and the top surface of the base 2. When the positioning boss 4 is inserted into the positioning recess, the sealing ring is compressed between the top surface of the base 2 and the bottom surface of the pad, forming a radial seal. The inner diameter of the sealing ring is slightly larger than the diameter of the boss, and the outer diameter is slightly larger than the diameter of the recess, ensuring that the sealing contact is maintained when the pad swings.

[0051] When the positioning boss 4 is inserted into the positioning recess, the self-lubricating coating on the surface of the boss and the wear-resistant metal gasket in the recess form a low-friction contact pair, so that the frictional resistance is minimal when the pad swings at a small angle under vehicle load, avoiding stress concentration or jamming caused by friction; the elastic sealing ring is compressed between the top surface of the base 2 and the bottom surface of the pad, forming a closed annular sealing cavity, which completely seals the mating interface between the positioning boss 4 and the positioning recess, preventing external radioactive dust, rainwater or oil from entering the mating gap, thus ensuring the cleanliness of the measurement interface of the pressure sensor and the displacement sensor 5 and preventing the sensor from failing due to contamination.

[0052] The combination of wear-resistant metal gaskets and self-lubricating coatings significantly reduces the friction coefficient of the ball joint coupling interface, ensuring the free swing of the gasket during leveling and preventing jamming. The design of the elastic sealing ring effectively prevents radioactive dust and moisture from entering the sensor measurement interface, improving the reliability and service life of the sensor in harsh environments, while avoiding a decrease in fitting accuracy due to the accumulation of contaminants.

[0053] In some embodiments, a remote monitoring module is also included, which transmits pressure data of each base 2, strain data and tilt data of the pad body 1, and fault diagnosis results to the central monitoring room in real time via wireless communication; after receiving an alarm to replace the pad body 1, the remote monitoring module automatically generates a maintenance work order containing the fault location, fault type and recommended handling solution.

[0054] The remote monitoring module includes a wireless communication unit (4G / 5G module or LoRa module), a data caching unit, and a power management unit, installed in a waterproof control box next to track 3, and connected to the controller's communication interface (RS485 or Ethernet). The remote monitoring module actively collects pressure data, pad strain data, tilt angle data, displacement data, and fault diagnosis results from each base 2 in the controller at a preset cycle (e.g., hourly). After packaging and encrypting the data, it uploads it to the server in the central monitoring room via a wireless network. The server is equipped with a data visualization platform that displays the pressure distribution cloud map, strain cloud map, and tilt angle status of each pad in real time in the form of charts. When the remote monitoring module receives a pad replacement alarm signal from the controller, it automatically triggers a maintenance work order generation program. Based on the pad number, it retrieves the installation location and historical maintenance records of the pad from the database, and generates a maintenance work order containing specific location coordinates, suggested treatment solutions, and a list of required spare parts, based on the fault type (plastic deformation or local damage), and pushes it to the handheld terminal of the maintenance personnel.

[0055] The remote monitoring module periodically requests sensor data and diagnostic status from the controller, encapsulates the data in JSON format, and sends it to the central server via wireless network. The server-side software parses the data and updates the corresponding pad status interface. When the pressure distribution cloud map shows significant skewness or the strain cloud map shows abnormally concentrated areas, the system automatically marks an early warning. If the controller diagnoses plastic deformation or local damage to the pad, the remote monitoring module immediately prioritizes the alarm signal and triggers the automated work order system. The system generates a structured maintenance work order based on preset rules (such as fault level, spare parts inventory, and maintenance personnel schedule), which includes the precise location of the faulty pad (latitude and longitude or site coordinates), a description of the fault phenomenon, suggested handling measures, and the required tools and spare parts models. This work order is then pushed to the on-duty maintenance personnel via a mobile application.

[0056] In some embodiments, the controller also has a fail-safe mode: when the strain sensor array or tilt sensor fails, the controller switches to a simplified leveling mode that relies solely on the pressure sensor; when some pressure sensors fail, the controller estimates the pressure value of the failed base 2 based on the data from the remaining effective pressure sensors and tilt sensors, and maintains the leveling function; when all sensors fail, the controller maintains the current height of the base 2 unchanged and issues an emergency alarm through the remote monitoring module, and the device operates in a purely mechanical support mode.

[0057] The fault-safe mode includes a three-level degradation operation strategy: Level 1: When the controller detects a communication interruption or data exceeding a reasonable range by the strain sensor array or tilt sensor, it automatically blocks the data channels of the failed sensors and switches to a simplified leveling mode that relies solely on the pressure sensors and displacement sensors 5 of each base 2. In this mode, the controller only performs leveling with pressure equalization as the goal and does not perform fault root cause diagnosis. Level 2: When some pressure sensors fail, the controller estimates the pressure value of the failed base 2 based on the pressure values ​​measured by the remaining effective pressure sensors, combined with the tilt data of the tilt sensors and the data of the displacement sensors 5 of each base 2, using the mechanical balance equation to maintain the continuity of the leveling function. Level 3: When all sensors fail, the controller immediately cuts off the drive power of all height adjustment mechanisms, locking the height of each base 2 at the state after the last effective adjustment, and issues the highest priority emergency alarm through the remote monitoring module. At this time, the device operates in a pure mechanical support mode, and the pad relies solely on the fixed height of the base 2 for support, no longer performing active leveling.

[0058] During each data acquisition cycle, the controller performs sensor self-checks. When a sensor is found to have lost data or exceed its range, it immediately marks the sensor as faulty. If the faulty sensor is a strain or tilt sensor, the controller automatically disables the fault diagnosis module and switches to a pressure-displacement dual closed-loop leveling mode. If the faulty sensor is a partial pressure sensor, the controller uses the principle of mechanical balance to establish a set of force balance equations based on the remaining pressure sensor measurements, the tilt direction of the pad given by the tilt sensor, and the detachment status of the displacement sensors 5 of each base 2, to solve for the approximate pressure value of the faulty base 2, thereby maintaining the calculation basis for pressure balance control. If all sensors fail, the controller forcibly disconnects the power supply to the motor driver through a hardware watchdog circuit, keeping the height adjustment mechanism in its current position. At the same time, it sends an emergency alarm signal to the central monitoring room through an independent wired interface, ensuring that the device can still provide basic track 3 protection functions even in the worst-case scenario.

[0059] The Level 3 fail-safe mode enables the system to maintain basic operation or safely shut down even if some or all sensors fail, preventing a single point of failure from paralyzing the entire protection device. By maintaining partial balancing function through sensor redundancy and mechanical estimation, the fault tolerance and availability of the system are improved. The highest level of emergency alarm and forced lockout mechanism ensures that the device can still provide safe mechanical support in a completely disabled state, meeting the special requirements of radioactive waste disposal sites for high equipment reliability.

[0060] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the invention (including the claims) is limited to these examples; within the framework of the invention, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of the different aspects of the invention as described above, which are not provided in the details for the sake of brevity.

[0061] This invention is intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A gantry crane track protection device, characterized in that, include: The pad body (1) is used to straddle the track (3) and the vehicle tires pass through the surface of the pad body (1); Multiple height-adjustable bases (2) are independently set between the bottom surface of the pad body (1) and the foundation. Each base (2) includes a height adjustment mechanism and a pressure sensor. The controller receives signals from all pressure sensors and controls the height adjustment mechanism to adjust the height of each base (2) with the goal of equalizing the pressure on each base (2); The pad body (1) is a multi-layer composite structure with a strain sensor array and an inclination sensor embedded inside. The controller also receives signals from the strain sensor array and the inclination sensor, and determines the root cause of unevenness as foundation settlement or deformation of the pad body (1) based on the multi-source data fusion results of the pressure sensor, strain sensor array and inclination sensor, and selects different leveling strategies based on the determination results.

2. The gantry crane track protection device according to claim 1, characterized in that, The multi-layer composite structure of the pad body (1) includes: The upper layer is a highly wear-resistant elastomer layer that directly withstands tire impact; The middle layer is a high molecular weight polyethylene main load-bearing layer; The bottom layer is a carbon fiber reinforced composite material layer, which contains the strain sensor array and the tilt sensor; The three-layer structure is combined through a hot-pressing composite process, so that when the pad body (1) is subjected to heavy load, the upper layer undergoes elastic compression to absorb the impact energy, while the bottom layer remains flat to ensure uniform pressure transmission.

3. The gantry crane track protection device according to claim 1, characterized in that, The base (2) has a positioning boss (4) on its top, and the bottom surface of the pad body (1) has a positioning recess that cooperates with the positioning boss (4). The pressure sensor is integrated on the top of the positioning boss (4) and directly contacts the bottom surface of the pad body (1). The base (2) also has a displacement sensor (5) on its side, which is used to measure the relative displacement between the positioning boss (4) and the positioning recess. The relative displacement data is used as the basis for judging whether the pad body (1) is detached or warped.

4. The gantry crane track protection device according to claim 1, characterized in that, The controller has a built-in fault root cause diagnosis module, which performs the following judgment logic: When the pressure distribution of each base (2) is uneven, the relative displacement data are close to zero, and the strain sensor array displays a bending mode, it is diagnosed that the pad body (1) has undergone plastic deformation, and the controller issues an alarm to replace the pad body (1). When the pressure of a certain side base (2) decreases, the corresponding relative displacement increases, and the tilt sensor shows that the pad body (1) tilts to that side, it is diagnosed as local settlement of the foundation, and the controller only adjusts the height of the base (2) on that side; When the pressure of all bases (2) drops evenly, the relative displacement is zero, and the strain sensor array is normal, it is diagnosed as overall foundation settlement, and the controller synchronously raises all bases (2); When the strain sensor array shows local strain abnormality and the corresponding base (2) pressure is abnormally low but the relative displacement is zero, it is diagnosed as local damage to the pad body (1), and the controller issues a shutdown alarm.

5. The gantry crane track protection device according to claim 4, characterized in that, The controller also determines the degree of plastic deformation of the pad body (1) based on the residual strain data of the strain sensor array. When the residual strain exceeds the preset threshold, the controller locks the height adjustment function of all bases (2) and forces the replacement of the pad body (1) before it can resume operation.

6. The gantry crane track protection device according to claim 1, characterized in that, The controller includes a vehicle passage detection module, which identifies vehicle passage status by monitoring the rate of change of pressure sensor signals. When the pressure change rate exceeds the preset threshold, it is determined that the vehicle is passing through. The controller suspends all height adjustment actions and marks the currently collected data as dynamic data and does not use it. Once the pressure change rate returns to below the threshold for a preset time, the controller resumes its adjustment function and collects static data for leveling calculation.

7. The gantry crane track protection device according to claim 1, characterized in that, The height adjustment mechanism is an electric screw jack, and each electric screw jack is equipped with an independent motor driver; the controller adopts a closed-loop proportional-integral-derivative control algorithm, takes the deviation between the pressure of each base (2) and the average pressure as input, outputs the adjustment amount of each electric screw jack, and the single adjustment step does not exceed 2mm, and the adjustment speed does not exceed 1mm / s.

8. The gantry crane track protection device according to claim 1, characterized in that, Wear-resistant metal pads are embedded in the positioning recess on the bottom surface of the pad body (1), and the positioning boss (4) on the top of the base (2) is coated with a self-lubricating coating. An elastic sealing ring is provided between the positioning boss (4) and the positioning recess to prevent radioactive dust or water from entering the coupling interface.

9. The gantry crane track protection device according to claim 1, characterized in that, It also includes a remote monitoring module, which transmits the pressure data of each base (2), the strain data and tilt data of the pad body (1), and the fault diagnosis results to the central monitoring room in real time via wireless communication; after receiving an alarm to replace the pad body (1), the remote monitoring module automatically generates a maintenance work order containing the fault location, fault type and recommended handling solution.

10. The gantry crane track protection device according to any one of claims 1 to 9, characterized in that, The controller also features a fail-safe mode: When the strain sensor array or tilt sensor fails, the controller switches to a simplified leveling mode that relies solely on the pressure sensor. When the pressure sensor fails, the controller estimates the pressure value of the failed base (2) based on the data of the remaining effective pressure sensor and tilt sensor, and maintains the leveling function. When all sensors fail, the controller maintains the current height of the base (2) and issues an emergency alarm through the remote monitoring module, and the device operates in a purely mechanical support mode.

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