A method, device, equipment and medium for evaluating guardrail performance

Abstract

The embodiments of the present application provide a method, apparatus, device and medium for evaluating guardrail performance, the method comprising: obtaining data to be processed collected by a guardrail performance detection device; calculating a reference protection energy and a reference load parameter corresponding to the target guardrail based on the data to be processed, wherein the reference protection energy is characterized by the energy absorbed by the target guardrail during deformation; when the load parameter corresponding to the guardrail to be detected does not meet the reference load parameter, calculating the ratio between the protection energy of the guardrail to be detected and the design protection energy to obtain the protection performance of the guardrail to be detected, wherein the design protection energy is represented by the reference protection energy. Through some embodiments of the present application, it is possible to establish a connection between the standards obtained in the test environment and the test in the field environment, thereby enabling accurate evaluation of guardrail performance.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of engineering detection technology, and specifically to a method, device, equipment and medium for evaluating guardrail performance. Background Art

[0002] The corrugated steel guardrail is an important traffic safety infrastructure. Its function is to prevent out-of-control vehicles from running off the road, reduce the severity of the consequences of traffic accidents, protect the lives of road users, and reduce property losses. In order to test the protective performance of corrugated steel guardrails, the relevant standard rules stipulate their protection levels, technical requirements and inspection rules. In related technologies, simply applying a continuous static load or a vehicle dynamic load to the guardrail plate, observing the deformation of the guardrail, and thus judging whether the performance of the guardrail meets the requirements, but the load-generating device is too heavy, and generally a 10-ton counterweight is used to generate static friction to overcome the reverse load. The hoisting and fixing process is relatively dangerous and inconvenient to transport, which increases time and economic costs and cannot meet the needs of rapid safety testing of in-service guardrails.

[0003] Therefore, how to quickly and accurately evaluate the performance of guardrails becomes a problem that needs to be solved. Summary of the Invention

[0004] Embodiments of the present application provide a method, apparatus, equipment, and medium for evaluating guardrail performance. Through some embodiments of the present application, at least the standards obtained in a test environment can be linked with the tests in a field environment, thereby enabling accurate evaluation of guardrail performance.

[0005] In the first aspect, the present application provides a method for evaluating guardrail performance, the method comprising: obtaining data to be processed collected by a guardrail performance detection device, wherein the data to be processed includes the guardrail displacement of the guardrail performance detection device for a target guardrail, the propulsion distance and the load of the guardrail performance detection device; calculating the reference protection energy and reference load parameters corresponding to the target guardrail based on the data to be processed, wherein the reference protection energy is characterized by the energy absorbed by the target guardrail during the deformation process; when the load parameters corresponding to the guardrail to be detected do not meet the reference load parameters, calculating the ratio between the protection energy of the guardrail to be detected and the design protection energy, and obtaining the protection performance of the guardrail to be detected, so as to maintain the guardrail to be detected based on the protection performance, wherein the design protection energy is represented by the reference protection energy.

[0006] Therefore, unlike the method in the related art of simply applying a continuous static load or a vehicle dynamic load to the guardrail board, observing the deformation of the guardrail, and thus judging whether the performance of the guardrail meets the requirements, the present application obtains the design protection energy of the guardrail after experiments in a test environment, and establishes a connection between the design protection energy and the parameters obtained in the field environment, so as to accurately and efficiently evaluate the performance of the guardrail.

[0007] In combination with the first aspect, in some embodiments of the present application, the reference load parameters are characterized by yield strength, ultimate load and detachment load; the reference protection energy and reference load parameters corresponding to the target guardrail are calculated based on the data to be processed, including: taking the maximum load in the data to be processed as the ultimate load; calculating multiple load-displacement ratios in the data to be processed, and taking the load corresponding to the load-displacement ratio that meets the preset conditions as the yield strength; taking the instantaneous load corresponding to the moment of fracture of the target guardrail as the detachment load, or taking the instantaneous load corresponding to the maximum guardrail displacement as the detachment load; calculating the reference protection energy based on the yield strength, ultimate load and detachment load.

[0008] Therefore, the embodiment of the present application can clarify the critical point of the guardrail state change by calculating the characteristic load value, and thus obtain the protective energy of the guardrail in different states based on the critical point.

[0009] In conjunction with the first aspect, in some embodiments of the present application, a load-displacement ratio corresponds to a load corresponding to a preset guardrail displacement, and the multiple load-displacement ratios include a first load-displacement ratio, which is any one of the multiple load-displacement ratios;

[0010] The first load-displacement ratio is obtained by the following formula (1):

[0011] K n = （F n -F n-1 ） / x (1)

[0012] in, K n represents the first load-displacement ratio, F n represents the load corresponding to the displacement of any guardrail, F n-1 represents the load corresponding to the displacement of the previous guardrail, x Indicates a preset advance distance.

[0013] Therefore, the embodiment of the present application can clarify the variation pattern between the load and displacement of the guardrail structure by calculating multiple load-displacement ratios.

[0014] In combination with the first aspect, in some embodiments of the present application, the load corresponding to the load-displacement ratio that meets the preset conditions is used as the yield strength, including: calculating the average value of t adjacent load-displacement ratios; when the average value is greater than a preset load-displacement threshold and the t load-displacement ratios are all greater than 0, the load corresponding to the load-displacement ratio with the smallest guardrail displacement among the t load-displacement ratios is used as the yield strength.

[0015] Therefore, the embodiment of the present application obtains the yield strength by calculating the average value of adjacent load-displacement ratios, and can find the critical value between the elastic deformation and plastic deformation of the guardrail.

[0016] In combination with the first aspect, in some embodiments of the present application, the calculation of the reference protection energy based on the yield strength, the ultimate load, and the breakaway load includes: taking the area corresponding to 0 to the yield strength as the first-stage protection energy, and the calculation process of the first-stage protection energy is shown in the following formula (2):

[0017] (2)

[0018] in, represents the first stage protection energy, represents the guardrail displacement of the monitoring point corresponding to the yield strength, represents the load between 0 and the yield strength, represents yield strength;

[0019] The area corresponding to the yield strength to the ultimate load is taken as the second-stage protection energy. The calculation process of the second-stage protection energy is shown in the following formula (3):

[0020] (3)

[0021] in, represents the second stage protection energy, represents the guardrail displacement of the monitoring point corresponding to the ultimate load, represents the guardrail displacement of the monitoring point corresponding to the yield strength, represents the ultimate load, represents the yield strength, x Indicates a preset guardrail displacement;

[0022] The area corresponding to the ultimate load to the maximum guardrail displacement is taken as the third-stage protection energy. The calculation process of the third-stage protection energy is shown in the following formula (4):

[0023] (4)

[0024] in, represents the third stage protection energy, is the breakaway load The guardrail displacement of the corresponding monitoring point, represents the breakaway load;

[0025] The first-stage protection energy, the second-stage protection energy, and the third-stage protection energy are added together to obtain the reference protection energy.

[0026] Therefore, the embodiment of the present application can accurately obtain the protection energy that the guardrail should have in various states by dividing the overall reference protection energy into three parts for calculation.

[0027] In combination with the first aspect, in some embodiments of the present application, the reference protection energy is a test reference protection energy, and the energy that can be absorbed by the guardrail posts and the guardrail panels connected thereto, which are n intermediate posts away from the target guardrail, is expressed by the following formula (5):

[0028] (5)

[0029] Where n represents the number of guardrail posts counted from the middle post of the target guardrail to the side. It represents the energy that can be absorbed by the nth guardrail post and the guardrail board connected to it. represents the energy that can be absorbed by the middle column and the connected guardrail panels of the target guardrail, c represents the coefficient, and e represents the natural constant;

[0030] described It is obtained by the following formula (6):

[0031] (6)

[0032]

[0033] in, represents the design protection energy, represents the first stage protection energy, represents the second stage protection energy, represents the third stage protection energy, u represents the number of guardrail posts counted from the middle post of the target guardrail to one side, v represents the number of guardrail posts counted from the middle post of the target guardrail to one side, the values ​​of u and v are determined by the size of the target guardrail, Q represents the test reference protection energy, It indicates the guardrail posts starting from the middle post of the target guardrail and counting towards the guardrail posts with a count of 1 on one side.

[0034] Therefore, the embodiment of the present application calculates the protective energy of the entire guardrail through the protective energy of a monitoring point, and can convert the standard under the test environment with the design standard under the real environment to obtain accurate design protective energy.

[0035] In combination with the first aspect, in some embodiments of the present application, the reference load parameter is expressed as: , ]、[ , ]and[ Q min , +∞], where is the minimum ultimate load in multiple tests on the target guardrail, is the maximum ultimate load, is the minimum yield strength, is the maximum yield strength, Q min It is the minimum test reference protection energy.

[0036] In combination with the first aspect, in some embodiments of the present application, the reference protection energy is an on-site reference protection energy, and the protection energy of the guardrail to be detected is obtained by the following formula (7):

[0037] (7)

[0038] in, represents the protective energy of the guardrail to be detected, Indicates the energy that can be absorbed by the guardrail post and the guardrail board connected to the guardrail post that is nth farthest from the middle post. Indicates the energy that can be absorbed by the middle column and the guardrail board connected to the guardrail to be tested, It represents the energy that can be absorbed by the guardrail board connected to the first column level on both sides of the middle column of the guardrail to be tested. a represents the guardrail column counted from the middle column of the guardrail to be tested to a on one side. b represents the guardrail column counted from the middle column of the guardrail to be tested to b on one side. Represents the on-site reference protection energy.

[0039] Therefore, this application determines the protective energy of the guardrail to be tested of the in-service guardrail by the ratio of the actual protective energy to the designed protective energy. This value has quantitative reference value when making maintenance decisions for highway traffic infrastructure.

[0040] In the second aspect, the present application provides a device for evaluating guardrail performance, the device comprising: a data acquisition module, configured to acquire data to be processed collected by a guardrail performance detection device, wherein the data to be processed includes the guardrail displacement of the guardrail performance detection device for a target guardrail, the propulsion distance and the load of the guardrail performance detection device; a parameter calculation module, configured to calculate the reference protection energy and reference load parameters corresponding to the target guardrail based on the data to be processed, wherein the reference protection energy is characterized by the energy absorbed by the target guardrail during the deformation process; a performance evaluation module, configured to calculate the ratio between the protection energy of the guardrail to be detected and the design protection energy when the load parameters corresponding to the guardrail to be detected do not meet the reference load parameters, and obtain the protection performance of the guardrail to be detected, so as to maintain the guardrail to be detected based on the protection performance, wherein the design protection energy is represented by the reference protection energy.

[0041] In combination with the second aspect, in some embodiments of the present application, the reference load parameters are characterized by yield strength, ultimate load and detachment load; the parameter calculation module is also configured to: take the maximum load in the data to be processed as the ultimate load; calculate multiple load-displacement ratios in the data to be processed, and take the load corresponding to the load-displacement ratio that meets the preset conditions as the yield strength; take the instantaneous load corresponding to the moment of fracture of the target guardrail as the detachment load, or take the instantaneous load corresponding to the maximum guardrail displacement as the detachment load; calculate the reference protection energy based on the yield strength, ultimate load and detachment load.

[0042] In conjunction with the second aspect, in some embodiments of the present application, a load-displacement ratio corresponds to a load corresponding to a preset guardrail displacement, and the multiple load-displacement ratios include a first load-displacement ratio, which is any one of the multiple load-displacement ratios;

[0043] The first load-displacement ratio is obtained by the following formula (1):

[0044] K n = （F n -F n-1 ） / x (1)

[0045] in, K n represents the first load-displacement ratio, F n represents the load corresponding to the displacement of any guardrail, F n-1 represents the load corresponding to the displacement of the previous guardrail,x Indicates a preset advance distance.

[0046] In combination with the second aspect, in some embodiments of the present application, the parameter calculation module is further configured to: calculate the average value of t adjacent load-displacement ratios; when the average value is greater than a preset load-displacement threshold and the t load-displacement ratios are all greater than 0, the load corresponding to the load-displacement ratio with the smallest guardrail displacement among the t load-displacement ratios is used as the yield strength.

[0047] In combination with the second aspect, in some embodiments of the present application, the parameter calculation module is further configured to: use the area corresponding to 0 to the yield strength as the first-stage protection energy, and the calculation process of the first-stage protection energy is shown in the following formula (2):

[0048] (2)

[0049] in, represents the first stage protection energy, represents the guardrail displacement of the monitoring point corresponding to the yield strength, represents the load between 0 and the yield strength, represents yield strength;

[0050] The area corresponding to the yield strength to the ultimate load is taken as the second-stage protection energy. The calculation process of the second-stage protection energy is shown in the following formula (3):

[0051] (3)

[0052] in, represents the second stage protection energy, represents the guardrail displacement of the monitoring point corresponding to the ultimate load, represents the guardrail displacement of the monitoring point corresponding to the yield strength, represents the ultimate load, represents the yield strength, x Indicates a preset guardrail displacement;

[0053] The area corresponding to the ultimate load to the maximum guardrail displacement is taken as the third-stage protection energy. The calculation process of the third-stage protection energy is shown in the following formula (4):

[0054] (4)

[0055] in, represents the third stage protection energy, is the breakaway load The guardrail displacement of the corresponding monitoring point, represents the breakaway load;

[0056] The first-stage protection energy, the second-stage protection energy, and the third-stage protection energy are added together to obtain the reference protection energy.

[0057] In conjunction with the second aspect, in some embodiments of the present application, the reference protection energy is a test reference protection energy, and the energy that can be absorbed by the guardrail posts and the guardrail panels connected thereto, which are n intermediate posts away from the target guardrail, is expressed by the following formula (5):

[0058] (5)

[0059] Where n represents the number of guardrail posts counted from the middle post of the target guardrail to the side. It represents the energy that can be absorbed by the nth guardrail post and the guardrail board connected to it. represents the energy that can be absorbed by the middle column and the connected guardrail panels of the target guardrail, c represents the coefficient, and e represents the natural constant;

[0060] described It is obtained by the following formula (6):

[0061] (6)

[0062]

[0063] in, represents the design protection energy, represents the first stage protection energy, represents the second stage protection energy, represents the third stage protection energy, u represents the number of guardrail posts counted from the middle post of the target guardrail to one side, v represents the number of guardrail posts counted from the middle post of the target guardrail to one side, the values ​​of u and v are determined by the size of the target guardrail, Q represents the test reference protection energy, It indicates the guardrail posts starting from the middle post of the target guardrail and counting towards the guardrail posts with a count of 1 on one side.

[0064] In conjunction with the second aspect, in some embodiments of the present application, the reference load parameter is expressed as: , ]、[ , ]and[ Q min , +∞], where is the minimum ultimate load in multiple tests on the target guardrail, is the maximum ultimate load, is the minimum yield strength, is the maximum yield strength, Q min is the minimum test reference protection energy. In combination with the second aspect, in some embodiments of the present application, the reference protection energy is an on-site reference protection energy, and the protection energy of the guardrail to be tested is obtained by the following formula (7):

[0065] (7)

[0066] in, represents the protective energy of the guardrail to be detected, Indicates the energy that can be absorbed by the guardrail post and the guardrail board connected to the guardrail post that is nth farthest from the middle post. Indicates the energy that can be absorbed by the middle column and the guardrail board connected to the guardrail to be tested, It represents the energy that can be absorbed by the guardrail board connected to the first column level on both sides of the middle column of the guardrail to be tested. a represents the guardrail column counted from the middle column of the guardrail to be tested to a on one side. b represents the guardrail column counted from the middle column of the guardrail to be tested to b on one side. Represents the on-site reference protection energy.

[0067] In a third aspect, the present application provides an electronic device comprising: a processor, a memory and a bus; the processor is connected to the memory via the bus, the memory stores a computer program, and when the computer program is executed by the processor, it can implement the method described in any embodiment of the first aspect.

[0068] In a fourth aspect, the present application provides a computer-readable storage medium having a computer program stored thereon, which, when executed, can implement the method described in any embodiment of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] Figure 1 A schematic diagram of a system composition for evaluating guardrail performance according to an embodiment of the present application;

[0070] Figure 2 This is one of the flow charts of a method for evaluating guardrail performance shown in an embodiment of the present application;

[0071] Figure 3 A top view of a guardrail performance testing device according to an embodiment of the present application;

[0072] Figure 4 The load-displacement curve of the guardrail structure shown in the embodiment of the present application;

[0073] Figure 5 A schematic diagram of load bearing is shown in an embodiment of the present application;

[0074] Figure 6 A schematic diagram of a device for evaluating guardrail performance according to an embodiment of the present application;

[0075] Figure 7 This is a schematic diagram of the composition of an electronic device shown in an embodiment of the present application. DETAILED DESCRIPTION

[0076] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present application.

[0077] The current "Highway Guardrail Safety Performance Evaluation Standard (JTG B05-01-2013)" is based on a real-vehicle collision test method. This method standardizes various technical parameters during the test process, such as vehicle type, mass, collision speed, collision angle, acceleration, and guardrail type requirements. The safety performance of the guardrail is primarily determined by the energy absorbed during the collision and the state of the vehicle and guardrail after the collision. For vehicles that do not penetrate the guardrail, it can be qualitatively assumed that the kinetic energy perpendicular to the guardrail before the collision is absorbed, which is a necessary condition for the guardrail structure to meet the designed protective energy requirements. While this test method cannot quantitatively determine the specific protective energy of the guardrail structure, it can intuitively determine whether it meets the energy lower limit specified by the protection level. Due to its strict test conditions, it is particularly suitable for factory performance testing of guardrails and performance verification of new guardrail structures. It is difficult to use for on-site testing of the protective performance of in-service guardrails.

[0078] Currently, there is a growing demand for rapid on-site testing and assessment of the impact energy of corrugated beam guardrails. Some testing and assessment methods draw on the core elements of actual vehicle collision standards. These methods, focusing on load-deformation and reducing the impact scale, utilize specialized devices such as hydraulic jacks, horizontal thrust cylinders, and pendulums to apply a continuous static load to guardrail fixtures, such as at the junctions between guardrail posts and barrier blocks or guardrail panels, or even to the guardrail panels themselves, to replace vehicle dynamic loads. These methods, in essence, are similar to actual vehicle collision tests. However, these methods lack a connection to existing actual vehicle collision standards and lack a substantial body of test data to serve as a foundation for evaluation, making it difficult to determine whether they are truly effective. Furthermore, the load-generating devices are heavy, typically requiring static friction generated by a 10-ton counterweight to overcome the opposing load. The lifting and securing process is dangerous and inconvenient to transport, increasing both time and financial costs, making them inadequate for the rapid safety testing of in-service guardrails. Therefore, it is necessary to propose an efficient guardrail assessment method and detection device to make the mesoscale in-service guardrail protection performance detection more safe and effective on the basis of feasibility.

[0079] The method steps in the embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0080] Figure 1 A schematic diagram of a guardrail performance evaluation system in accordance with some embodiments of the present application is provided. The system includes a guardrail performance testing device 110 and a guardrail performance evaluation device 120. Specifically, the guardrail performance testing device 110 tests a target guardrail, obtains data to be processed, and transmits the processed data to the guardrail performance evaluation device 120. The guardrail performance evaluation device 120 then evaluates the guardrail to be tested based on its designed protective energy and determines its protective performance.

[0081] It can be understood that the design protection energy is the guardrail protection energy obtained based on the "Highway Guardrail Safety Performance Evaluation Standard (JTG B05-01-2013)", that is, the design protection energy is the industry standard.

[0082] The following describes a method for evaluating guardrail performance performed by a guardrail performance evaluation device in an embodiment of the present application. It is understood that the guardrail performance evaluation device can be any device capable of performing the method, such as a server or an electronic device such as a computer.

[0083] At least to solve the problems in the background technology, such as Figure 2 As shown, some embodiments of the present application provide a method for evaluating guardrail performance, the method comprising:

[0084] S210, obtaining data to be processed collected by the guardrail performance testing equipment.

[0085] Guardrail performance testing equipment leverages the characteristics of the guardrail's composite structure to simultaneously generate thrust and tension. The equipment and guardrail structure are treated as a single entity. While maintaining overall force equilibrium, the equipment applies a controlled static thrust load to the composite steel corrugated beam guardrail panels according to specified conditions. The testing process is similar to drawing a bow, but the bow produces recoverable elastic deformation, while the guardrail structure undergoes irreversible plastic deformation. The guardrail's protective capabilities are assessed by calculating the energy absorbed during this plastic deformation.

[0086] In one embodiment of the present application, in order to determine whether the protective performance of the corrugated beam guardrail in use meets the design requirements, the present application tests the target guardrail through a guardrail performance testing device, wherein the guardrail performance testing device is as follows: Figure 3 As shown, the guardrail performance testing equipment includes: an equipment display board 301, an electric thrust cylinder 302, an equipment platform 303, a monitoring point A (304), a monitoring point B (309), a thruster 305, a thruster tooling 306, a steel wire rope 307, a guardrail anti-blocking block 308, a guardrail plate 310 and a guardrail column 311.

[0087] The electric thrust cylinder 302 is a component of the equipment that generates the top thrust, and adopts a combination of a servo motor and a thruster. The servo motor is powered by a generator. The thruster has a return function, the thrust range is between 0-100KN, and the thrust length of the thruster is at least 1m. In order to ensure the sampling frequency of the data, a uniform propulsion method is adopted with adjustable speed, and the adjustment range should be between 1cm / s and 5cm / s. The electric thrust cylinder is equipped with a pressure sensor, which can collect the thrust generated by itself. In the case of uniform propulsion, it is equal to the load acting on the guardrail. The measurement accuracy of the pressure sensor is at least 1N, and the sampling frequency is at least 10Hz.

[0088] The thruster tooling 306 is a column steel structure used when the thruster end contacts the guardrail part to be tested in order to ensure that the thruster and the guardrail part to be tested are fully stressed and to avoid slipping. When the thrust is applied, the tooling will always support each wave crest of the corrugated plate of the corrugated beam guardrail. The tooling is rigidly connected to the thruster end and can be disassembled. In order to adapt to the shape and size of the troughs of different corrugated beam guardrail plates, a variety of tooling can be processed and installed and disassembled at the thruster end. For double-wave B-grade steel guardrails, the tooling height shall not be less than 40cm; for triple-wave A-grade steel guardrails, the tooling height shall not be less than 60cm.

[0089] Wire rope 307 generates tension to balance the thrust reaction force. The wire rope has a diameter of at least 50 mm and is secured to the bottom of the guardrail post at both ends via wire rope connectors. These connectors are hollow circular or square columns that fit over the outer ring of the guardrail post, with an inner diameter slightly larger than the guardrail post's outer diameter.

[0090] The electric thrust cylinder 302 is equipped with a guardrail displacement detection device to detect the horizontal extension length of the thruster 305 and record the displacement of monitoring point A No. 1. While ensuring that the guardrail column does not spontaneously tip over, that is, the connecting parts and the guardrail plate always maintain full contact, the horizontal advancement length of the thruster is equal to the displacement of the guardrail combination structure in the horizontal direction.

[0091] A triaxial displacement detection device is installed at the monitoring point of the guardrail post to detect the displacement of monitoring point B during the tilting process. The horizontal propulsion of thruster 305 not only causes horizontal displacement of the guardrail portion to be tested, but also causes vertical height changes. The triaxial displacement detector decomposes the displacement of monitoring point B in Cartesian coordinate space to obtain the displacement components Sx, Sy, and Sz along the X, Y, and Z axes, allowing tracking of the entire displacement change of monitoring point B.

[0092] In addition to installing the above-mentioned main functional components, the equipment platform needs to be equipped with an equipment display board 301. After the equipment reaches the detection position, the display board is extended to expand the contact area between the equipment and the road surface to prevent the equipment from overturning due to unbalanced vertical force.

[0093] In other words, the guardrail push test involves using guardrail performance testing equipment to perform standardized, repetitive loading on the guardrail structure within the test site, collecting and processing thrust and displacement data to determine the load-deformation patterns of the guardrail. The test involves the following steps.

[0094] First, prepare the test guardrail materials. Before the test begins, prepare the test guardrail materials, transport them to the test site, and inspect the guardrail material and structural parameters to ensure they meet the test requirements. For each test group, use the same guardrail material type and specifications. Ensure consistent soil conditions at the test site, and ensure the posts are buried at the same depth and vertical distance from the slope. Once these conditions are met, repeat the guardrail push-up test t times within the same test group.

[0095] Next, the guardrail's lower soil foundation and guardrail construction were carried out. The subgrade soil beneath the guardrail was uniformly constructed at the test site. This test method uses a structure consisting of three guardrail posts and two guardrail panels as an example to ensure that the subgrade slope meets the 1:1.5 slope requirement. Within the same set of guardrail tests, the vertical distance between each guardrail post and the slope is equal. According to construction specifications, guardrail posts are constructed on the subgrade, and the installation and anchoring of related components, such as guardrail panels, are completed. This ensures that the guardrail posts, panels, and associated components are accurately positioned to meet design specifications.

[0096] Next, secure the equipment. Move the test equipment to the guardrail location to be tested, typically the middle post between three guardrail posts. Apply force to the guardrail panel that overlaps the middle post. Slide the wire rope connector over the bottom of each guardrail post. Secure the connector to the test equipment platform with the wire rope and tighten. Finally, pull out the platform's expansion panel.

[0097] Next, select the monitoring points. Connect the horizontal linear displacement detection device to the end of the propeller to measure the propeller's extension distance, which is the displacement of monitoring point A (number 1). Connect and secure the triaxial displacement detection device to monitoring point B on the guardrail. Monitoring point B is located 60-80 mm below the top of the guardrail post and at a vertical distance H from the ground.

[0098] Finally, start the electric thrust cylinder, start the test and collect the data to be processed of the target guardrail. Start the electric thrust cylinder, and when the thruster is extended to contact the target guardrail to be tested, start recording and storing the test data. The test data includes the thruster pressure sensor data, the horizontal propulsion distance of monitoring point A, and the three-axis displacement of monitoring point B. After the thruster end contacts the target guardrail to be tested and propels a certain distance D, it is used as the end point of data collection. The format of the obtained test data is shown in Table 1. Since the spatial displacement detection of monitoring point B uses a three-axis displacement detector, its spatial displacement S can be decomposed into Sx, Sy, and Sz, F is the thruster's thrust pressure value, L is the thruster's horizontal extension distance, t is the number of tests, and n is the data sequence number. For example, the displacement of monitoring point B, the thruster extension distance, and the load size corresponding to the fifth data of the second push test should be recorded as S2-5, L2-5, and F2-5, respectively.

[0099] Table 1 Data collection table for the push-up test of corrugated beam guardrail

[0100]

[0101] When the thruster tip contacts the target guardrail and propels the target distance D, the test data recording is interrupted. The equipment platform display board is retracted, and the test equipment is moved to the next test site in the same test group and the above experimental steps are repeated.

[0102] It should be noted that the data to be processed include the guardrail displacement of the guardrail performance testing equipment for the target guardrail, the advancement distance and load of the guardrail performance testing equipment. Among them, the guardrail displacement of the target guardrail is obtained by collecting data from the above-mentioned monitoring point B, and the advancement distance of the guardrail performance testing equipment is obtained by collecting data from the above-mentioned monitoring point A.

[0103] S220: Calculate reference protection energy and reference load parameters corresponding to the target guardrail based on the data to be processed.

[0104] After the completion of t tests in the same group, the test data should be processed and analyzed in a timely manner to check whether there are any abnormalities in the data, and the data results of each test in the same group should be compared to obtain the relationship between the thrust generated by the detection equipment and the propulsion distance, and then obtain the reference load parameters and reference protection energy.

[0105] The specific implementation process of calculating the reference protection energy and reference load parameters is as follows:

[0106] S2201: Decompose the thruster extension distance data of each test into equally spaced thrust distance points, and calculate the average thrust at the same spatial displacement points in the same test.

[0107] The horizontal extension of the propeller is used as the horizontal axis, each x-length is used as the displacement interval, and the vertical axis is used to plot the thrust as it changes with displacement. To improve the efficiency of the system, the thrust is normalized using linear interpolation.

[0108] Taking the first test data as an example, we first look for the point that is closest to x and smaller than x, which is recorded as , and the thrust corresponding to this displacement is ; Then, find the point that is closest to x and greater than x, recorded as , and the thrust corresponding to this displacement is .

[0109] According to the linear interpolation formula, the thrust corresponding to the displacement x can be calculated .

[0110]

[0111] After linear interpolation, the original test data sequence is converted into data with equally spaced displacements. The equally spaced displacement data obtained after processing the same group of t tests are averaged, as shown in Table 2 below. The average thrust of the first x is , the average thrust of the second 2x is For example, if the interval of equal displacement is set to 5 cm, the average thrust when advancing 5 cm is , the average thrust when advancing 10cm is .

[0112] Table 2 Equal-interval thrust conversion table

[0113]

[0114] It is understood that the positive integer x ranges from [1, 10], in mm, and the positive integer n ranges from [30, 100]. Taking x as 5 mm, n as 60, and the thruster's horizontal propulsion distance reaching 300 mm as an example, a thrust-distance curve is established for the horizontal work performed by the thruster on the guardrail structure.

[0115] S2202: Summarize the load-displacement variation law of the guardrail structure, find the numerical characteristics of the thrust load-displacement variation, and propose a method for determining the load characteristic value.

[0116] The corrugated steel guardrail is a typical form of semi-rigid guardrail. It is a continuous structure composed of corrugated guardrail panels spliced ​​together and supported by columns. It uses the deformation of the soil foundation, columns, and beams to absorb collision energy. Under the action of uniform static force, it can be assumed that the guardrail structure is in a state of force equilibrium at each point in time, and the work curve of the detection equipment can be used to characterize the load-displacement variation of the guardrail structure. The load-displacement variation of the composite guardrail structure has certain similarities with the load variation of a rigid object subjected to lateral force. However, because the guardrail structure itself is also flexible, elastic and plastic deformations are simultaneously generated during the pressure-bearing process. This variation can be described as the following three stages:

[0117] In the first stage, the load increases rapidly, and the displacement is not obvious. Cracks appear at the connection between the lower part of the guardrail post and the soil foundation. The crack extension direction is about 45 degrees to the edge of the soil foundation slope. The barrier block between the guardrail board and the guardrail post is slightly compressed, the guardrail post tilts, and the guardrail structure is in the elastic deformation range. In the second stage, the load increases slowly, and the displacement increases rapidly. The connection between the lower part of the guardrail post and the soil foundation cracks, and the cracks increase rapidly. The displacement change is mainly due to the tilt of the guardrail post caused by soil cracking. The guardrail post and guardrail board collapse simultaneously, and the guardrail structure is in a yield state. Plastic deformation produces irreversible permanent deformation. During the yield process, the pressure is the greatest at the location of the fixing screws between the guardrail boards, and cracks appear first, resulting in a local decrease in load, but the overall process is a slow increase. In the third stage, the horizontal load shows a downward trend. Because the guardrail post is buried deep and is affected by the traction of the adjacent guardrail boards, although the guardrail structure is in a balanced state, its resistance is slowly lost, and the guardrail structure is in a state of plastic instability.

[0118] It should be noted that the reference protection energy and reference load parameters are parameters obtained after testing the target guardrail in an experimental environment. The reference protection energy is characterized by the energy absorbed by the target guardrail during the deformation process, and the reference load parameter is characterized by the yield strength, ultimate load and breakaway load. For example, the reference load parameter is expressed as: , ]、[ , ]and[ Q min , +∞], where The minimum limit load in multiple tests of the target guardrail. is the maximum ultimate load, is the minimum yield strength, is the maximum yield strength, Q min It is the minimum test reference protection energy.

[0119] Specifically, such as Figure 4 As shown, Figure 4 The curve established for the guardrail structure load and displacement, the horizontal axis is the guardrail displacement monitored by monitoring point B, the vertical axis is the load corresponding to the guardrail displacement, there are 3 characteristic load values ​​on the curve, the first characteristic load value is the yield strength of the guardrail structure (with yield strength The corresponding guardrail displacement is expressed as ), corresponds to the end point of the first stage of elastic deformation and the starting point of the second stage of plastic deformation. After exceeding this point, the guardrail enters an irreversible plastic deformation process, reflecting the elastic limit of the guardrail and the foundation. After the jacking force is removed, the guardrail can return to its original state. The second characteristic load value is the end point of the second stage, corresponding to the ultimate load of the overall system composed of the soil and guardrail structure. (with ultimate load The corresponding guardrail displacement is expressed as ), which reflects the maximum load-bearing capacity of the entire test structure. After exceeding this point, the load gradually decreases. The third characteristic load value is the breakaway load corresponding to the end point of the third stage. (with the release load The corresponding guardrail displacement is expressed as ), reflects the instantaneous load when the thruster of the detection equipment slips off the guardrail structure or the stressed part of the guardrail is completely broken. After separation, the load quickly returns to zero. This scenario simulates the situation where a vehicle rushes out of the road or breaks the guardrail after hitting the guardrail. The load displacement change trend after separation can be predicted based on the separation load.

[0120] In one embodiment of the present application, the calculation process of the three characteristic load values ​​is as follows:

[0121] Ultimate load: The maximum load in the data to be processed is used as the ultimate load.

[0122] That is to say, = max(F n ） , determine that in the same group of M experiments, The maximum and minimum values ​​of 、 .

[0123] For example, the data to be processed includes load values ​​of three tests (M=3). The maximum load value in each test is selected as the ultimate load. In the process of determining the reference load parameters, the maximum and minimum values ​​of the ultimate loads in these three tests are selected as the judgment criteria for the ultimate load, which can be expressed as: , ].

[0124] Yield Strength: Calculates multiple load-displacement ratios in the data to be processed, and uses the load corresponding to the load-displacement ratio that meets the preset conditions as the yield strength.

[0125] In one embodiment of the present application, the process of calculating multiple load-displacement ratios in the data to be processed is as follows:

[0126] A load-displacement ratio corresponds to a load corresponding to a preset guardrail displacement (i.e., an interval of equally spaced displacements), the multiple load-displacement ratios include a first load-displacement ratio, and the first load-displacement ratio is any one of the multiple load-displacement ratios;

[0127] The first load-displacement ratio is obtained by the following formula (1):

[0128] K n = （F n -F n-1 ） / x (1)

[0129] in, K n represents the first load-displacement ratio, F n represents the load corresponding to the displacement of any guardrail, F n-1 Indicates the load corresponding to the last guardrail displacement (for example, the guardrail displacement corresponding to the last advancement of 5mm). x Indicates a preset advance distance.

[0130] In one embodiment of the present application, the calculation process of using the load corresponding to the load-displacement ratio that meets the preset conditions as the yield strength is as follows:

[0131] First, calculate the average value of t adjacent load-displacement ratios. The t load-displacement ratios are represented by K n ,K n+1 ,…K n+t , the average value of t load-displacement ratios is ( K n +K n+1 +…+K n+t ) / t. It is understandable that t can be 3 or 5.

[0132] Then, when the average value is greater than the preset load-displacement threshold and all t load-displacement ratios are greater than 0, the load corresponding to the load-displacement ratio with the smallest guardrail displacement among the t load-displacement ratios is taken as the yield strength. The maximum and minimum values ​​of 、 .

[0133] For example, if t=3 and n=1, then the load-displacement ratio of t is K 1 +K 2 +K 3. The average value of the three load-displacement ratios is ( K 1 +K 2 +K 3) / 3, if ( K 1 +K 2 +K 3) / 3 ＜ K s ,and K 1 、K 2 and K 3 are all greater than 0, then the load with the smallest guardrail displacement among the three load-displacement ratios K 1 is the yield strength. K s The value can be 20. K s It can be changed according to the structure of the guardrail. The combined structure of two steel corrugated beam guardrails on the soil foundation under the test conditions of this application corresponds to K s The value is 20.

[0134] Breakaway load: The instantaneous load corresponding to the moment the target guardrail breaks is used as the breakaway load, or the instantaneous load corresponding to the maximum guardrail displacement is used as the breakaway load.

[0135] Specifically, the instantaneous load when the propeller of the detection equipment and the guardrail structure slip or the guardrail stress part is completely broken is used as the If the thruster tip contacts the guardrail at the position to be tested and does not separate from it during the process of advancing the specified distance D, the instantaneous load value when the distance is D is used as the separation load.

[0136] In one embodiment of the present application, the reference protection energy is calculated based on the yield strength, the ultimate load and the breakaway load.

[0137] Specifically, the area corresponding to 0 to yield strength is taken as the first stage protection energy. The calculation process of the first stage protection energy is shown in the following formula (2):

[0138] (2)

[0139] in, Indicates the first stage protection energy, The guardrail displacement at the monitoring point corresponding to the yield strength is represented by represents the load between 0 and yield strength, represents yield strength;

[0140] The area corresponding to the yield strength to the ultimate load is taken as the second stage protection energy. The calculation process of the second stage protection energy is shown in the following formula (3):

[0141] (3)

[0142] in, Indicates the second stage protection energy, Indicates the guardrail displacement at the monitoring point corresponding to the ultimate load, The guardrail displacement at the monitoring point corresponding to the yield strength is represented by represents the ultimate load, represents the yield strength, x Indicates a preset guardrail displacement;

[0143] The area corresponding to the ultimate load to the maximum guardrail displacement is taken as the third stage protection energy. The calculation process of the third stage protection energy is shown in the following formula (4):

[0144] (4)

[0145] in, Indicates the third stage of protection energy, Is off load The guardrail displacement of the corresponding monitoring point, Indicates detachment from load;

[0146] The first stage protection energy, the second stage protection energy and the third stage protection energy are added together to obtain the reference protection energy.

[0147] Specifically, the area between the load-displacement curve of the guardrail structure and the horizontal displacement coordinate axis is the work Q done by the thrust on the guardrail during the test. Under the condition of uniform propulsion, this value also represents the energy absorbed by the guardrail. According to the different stages of propulsion, it can be expressed as:

[0148]

[0149] In the formula 、 、 They correspond to the actual work done by the thrust force on the guardrail in the three stages of the guardrail deformation process. To simplify the calculation, the guardrail structure load-displacement trend line is obtained by data fitting, which can be , approximate as a right triangle, The corresponding load is approximated as a quadratic function, Approximating it as a right trapezoid, we have:

[0150] Energy absorbed in the first stage ,in is the yield strength The corresponding horizontal displacement of monitoring point A.

[0151] Energy absorbed in the second stage ,in is the ultimate load The corresponding horizontal displacement of monitoring point A.

[0152] Energy absorbed in the third stage ,in Is off load The corresponding horizontal displacement of monitoring point A.

[0153] Find the maximum and minimum values ​​of the guardrail's absorbed energy (i.e., the test reference protection energy) in the M tests of the same group, and record them as 、 .

[0154] S230: When the load parameters corresponding to the guardrail to be tested do not meet the reference load parameters, the ratio between the protection energy of the guardrail to be tested and the design protection energy is calculated to obtain the protection performance of the guardrail to be tested.

[0155] Specifically, according to the "Highway Guardrail Safety Performance Evaluation Standard (JTG B05-01-2013)", the guardrail length for actual vehicle collision tests should be no less than 70m. Assuming each corrugated beam guardrail panel is 4m long, a full-scale guardrail structure should have at least 18 panels and 19 connected columns. An exponential model is used to predict the protective energy of eight full-scale guardrail panels from the two-panel, three-column test guardrail structure to its left and right sides. The energy that can be absorbed by the guardrail columns and connected guardrail panels, n number of columns away from the center column of the tested guardrail structure, is expressed as:

[0156]

[0157] Where n represents the number of guardrail posts counted from the middle post of the target guardrail to one side. is a coefficient, which is determined according to the guardrail design protection energy and the corrugated beam steel guardrail structure. The determination method is as follows.

[0158] The guardrail design protection energy can be expressed as:

[0159]

[0160] in

[0161] Taking a Class B guardrail with a design protection energy of 70 kJ as an example, the relationship between the guardrail design protection energy in the actual vehicle collision standard test and this test method can be obtained using the planning solution method:

[0162]

[0163] The A-level guardrail with a design protection energy of 160KJ corresponds to different And the c value, where c=-0.035 is obtained by calculation.

[0164] On-site testing (guardrails on highways) The process of testing the protective capacity of in-service soil-based corrugated steel guardrails is the same as the test steps. After obtaining the yield strength, ultimate load and absorbed energy of the guardrail to be tested, After comparison with the test reference value, when the above three tested parameters are all within the reference range , ]、[ , ]、[ ,∞], it can be considered that the guardrail under test still meets the design standards, and other guardrails in the road section constructed at the same time can continue to be used, while the two guardrail panels and three columns under test need to be replaced and connected to other guardrails.

[0165] When any parameter is not within the reference range, it is considered that the guardrail's protection capacity has failed to reach the designed protection capacity. The conversion can be done using the expression of design protection energy, namely:

[0166]

[0167] in, represents the protective energy of the guardrail to be detected, Indicates the energy that can be absorbed by the guardrail post and the guardrail board connected to the guardrail post that is nth farthest from the middle post. Indicates the energy that can be absorbed by the middle column and the guardrail board connected to the guardrail to be tested, It represents the energy that can be absorbed by the guardrail board connected to the first column level on both sides of the middle column of the guardrail to be tested. a represents the guardrail column counted from the middle column of the guardrail to be tested to a on one side. b represents the guardrail column counted from the middle column of the guardrail to be tested to b on one side. Represents the on-site reference protection energy.

[0168] It should be understood that the test reference protection energy is obtained by testing the target guardrail in the laboratory, while the field reference protection energy is obtained by testing the guardrail under test on the road. The middle column is the column where the guardrail performance testing equipment applies force to the guardrail.

[0169] The ratio of the designed protective energy to the protective energy of the guardrail to be tested can provide a quantitative reference value when making maintenance decisions for highway traffic infrastructure.

[0170] After S230, it is also possible to predict the reasons why the in-service guardrail does not meet the designed protection capabilities.

[0171] Specifically, when the guardrail in service no longer meets the designed protection capability, it is necessary to evaluate whether the insufficient protection capability is caused by the soil quality or insufficient burial depth of the guardrail post. The X, Y, and Z displacement components Sx, Sy, and Sz of the Cartesian coordinate system collected by the three-axis displacement detector are used to fit the displacement trajectory of the monitoring point B during the bending process of the guardrail post.

[0172] The position of monitoring point B before pushing is used as the origin of the coordinate axis, the load pushing direction is used as the positive half axis of the X axis, the vertical direction is used as the Y axis, and the direction perpendicular to the pushing direction and parallel to the guardrail is used as the Z axis to establish a Cartesian three-dimensional rectangular coordinate system, as shown in the following example: Figure 5 As shown, when the thrust (load F) is always perpendicular to the guardrail plane, Sz = 0; the propeller advances at a constant speed, and the monitoring point B moves at a constant speed along the X-axis and Y-axis as the column tilts. Its trajectory is an arc, and the radius of the arc trajectory is found by fitting the least squares method. And the coordinates of the fitting circle center O (X0, Y0) in the X, Y plane to evaluate the soil foundation conditions and guardrail burial depth. The fitting process uses the following formula:

[0173] =

[0174] in , , ;x i is the horizontal coordinate of the i-th data of monitoring point B in the X, Y plane, y i is the vertical coordinate of the i-th data of monitoring point B in the X, Y plane, m is the number of data groups participating in the fitting, a, b and c represent the intermediate parameters, Represents the coordinates of the center of the fitted circle.

[0175] When R>H, the bending point of the column is below the surface of the foundation, and the foundation cannot withstand the shear force when the column tilts. It is necessary to increase the soil compaction or increase the burial depth of the guardrail column. H represents the vertical distance between monitoring point B and the ground.

[0176] A specific embodiment of a method for evaluating guardrail performance is described above, and a device for evaluating guardrail performance will be described below.

[0177] like Figure 6 As shown, some embodiments of the present application provide a device 600 for evaluating guardrail performance, which includes: a data acquisition module 610, a parameter calculation module 620 and a performance evaluation module 630.

[0178] The data acquisition module 610 is configured to acquire the data to be processed collected by the guardrail performance detection equipment, wherein the data to be processed includes the guardrail displacement of the guardrail performance detection equipment for the target guardrail, the propulsion distance and the load of the guardrail performance detection equipment; the parameter calculation module 620 is configured to calculate the reference protection energy and reference load parameters corresponding to the target guardrail based on the data to be processed, wherein the reference protection energy is characterized by the energy absorbed by the target guardrail during the deformation process; the performance evaluation module 630 is configured to calculate the ratio between the protection energy of the guardrail to be detected and the design protection energy when the load parameter corresponding to the guardrail to be detected does not meet the reference load parameter, and obtain the protection performance of the guardrail to be detected, so as to maintain the guardrail to be detected based on the protection performance, wherein the design protection energy is represented by the reference protection energy.

[0179] In some embodiments of the present application, the reference load parameters are characterized by yield strength, ultimate load and breakaway load; the parameter calculation module 620 is further configured to: take the maximum load in the data to be processed as the ultimate load; calculate multiple load-displacement ratios in the data to be processed, and take the load corresponding to the load-displacement ratio that meets the preset conditions as the yield strength; take the instantaneous load corresponding to the moment of fracture of the target guardrail as the breakaway load, or take the instantaneous load corresponding to the maximum guardrail displacement as the breakaway load; calculate the reference protection energy based on the yield strength, ultimate load and breakaway load.

[0180] In some embodiments of the present application, a load-displacement ratio corresponds to a load corresponding to a preset guardrail displacement, and the plurality of load-displacement ratios include a first load-displacement ratio, which is any one of the plurality of load-displacement ratios;

[0181] The first load-displacement ratio is obtained by the following formula (1):

[0182] K n = （F n -F n-1 ） / x (1)

[0183] in, K n represents the first load-displacement ratio, F n represents the load corresponding to the displacement of any guardrail, F n-1 represents the load corresponding to the displacement of the previous guardrail, x Indicates a preset advance distance.

[0184] In some embodiments of the present application, the parameter calculation module 620 is further configured to: calculate the average value of t adjacent load-displacement ratios; when the average value is greater than a preset load-displacement threshold and the t load-displacement ratios are all greater than 0, the load corresponding to the load-displacement ratio with the smallest guardrail displacement among the t load-displacement ratios is used as the yield strength.

[0185] In some embodiments of the present application, the parameter calculation module 620 is further configured to: use the area corresponding to 0 to the yield strength as the first stage protection energy, and the calculation process of the first stage protection energy is shown in the following formula (2):

[0186] (2)

[0187] in, represents the first stage protection energy, represents the guardrail displacement of the monitoring point corresponding to the yield strength, represents the load between 0 and the yield strength, represents yield strength;

[0188] The area corresponding to the yield strength to the ultimate load is taken as the second-stage protection energy. The calculation process of the second-stage protection energy is shown in the following formula (3):

[0189] (3)

[0190] in, represents the second stage protection energy, represents the guardrail displacement of the monitoring point corresponding to the ultimate load, represents the guardrail displacement of the monitoring point corresponding to the yield strength, represents the ultimate load, express, x Indicates a preset guardrail displacement;

[0191] The area corresponding to the ultimate load to the maximum guardrail displacement is taken as the third-stage protection energy. The calculation process of the third-stage protection energy is shown in the following formula (4):

[0192] (4)

[0193] in, represents the third stage protection energy, is the breakaway load The guardrail displacement of the corresponding monitoring point, represents the breakaway load;

[0194] The first-stage protection energy, the second-stage protection energy, and the third-stage protection energy are added together to obtain the reference protection energy.

[0195] In some embodiments of the present application, the reference protection energy is a test reference protection energy, and the energy that can be absorbed by the guardrail posts and the guardrail panels connected thereto, which are n intermediate posts away from the target guardrail, is expressed by the following formula (5):

[0196] (5)

[0197] Where n represents the number of guardrail posts counted from the middle post of the target guardrail to the side. It represents the energy that can be absorbed by the nth guardrail post and the guardrail board connected to it. represents the energy that can be absorbed by the middle column and the connected guardrail panels of the target guardrail, c represents the coefficient, and e represents the natural constant;

[0198] described It is obtained by the following formula (6):

[0199] (6)

[0200]

[0201] in, represents the design protection energy, represents the first stage protection energy, represents the second stage protection energy, represents the third stage protection energy, u represents the number of guardrail posts counted from the middle post of the target guardrail to one side, v represents the number of guardrail posts counted from the middle post of the target guardrail to one side, the values ​​of u and v are determined by the size of the target guardrail, Q represents the test reference protection energy, It indicates the guardrail posts starting from the middle post of the target guardrail and counting towards the guardrail posts with a count of 1 on one side.

[0202] In some embodiments of the present application, the reference load parameter is expressed as: , ]、[ , ]and[ Q min , +∞], where is the minimum ultimate load in multiple tests on the target guardrail, is the maximum ultimate load, is the minimum yield strength, is the maximum yield strength, Q min is the minimum test reference protection energy. In combination with the second aspect, in some embodiments of the present application, the reference protection energy is an on-site reference protection energy, and the protection energy of the guardrail to be tested is obtained by the following formula (7):

[0203] (7)

[0204] in, represents the protective energy of the guardrail to be detected, Indicates the energy that can be absorbed by the guardrail post and the guardrail board connected to the guardrail post that is nth farthest from the middle post. Indicates the energy that can be absorbed by the middle column and the guardrail board connected to the guardrail to be tested, It represents the energy that can be absorbed by the guardrail board connected to the first column level on both sides of the middle column of the guardrail to be tested. a represents the guardrail column counted from the middle column of the guardrail to be tested to a on one side. b represents the guardrail column counted from the middle column of the guardrail to be tested to b on one side. Indicates the on-site reference protection energy. In the embodiment of the present application, Figure 6 The modules shown can achieve Figures 1 to 5 Each process in the method embodiment. Figure 6 The operations and / or functions of each module in Figures 1 to 5 For details, please refer to the description in the above method embodiment. To avoid repetition, detailed description is appropriately omitted here.

[0205] like Figure 7 As shown, an embodiment of the present application provides an electronic device 700, including: a processor 710, a memory 720 and a bus 730, wherein the processor is connected to the memory via the bus, and the memory stores computer-readable instructions. When the computer-readable instructions are executed by the processor, they are used to implement a method as described in any one of the above embodiments. For details, please refer to the description in the above method embodiments. To avoid repetition, detailed description is appropriately omitted here.

[0206] The bus is used to enable direct connection and communication between these components. In the embodiments of the present application, the processor can be an integrated circuit chip with signal processing capabilities. The aforementioned processor can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic device, discrete gate or transistor logic device, or discrete hardware component. It can implement or execute the various methods, steps, and logic block diagrams disclosed in the embodiments of the present application. The general-purpose processor can be a microprocessor or any conventional processor.

[0207] The memory may be, but is not limited to, a random access memory (RAM), a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), etc. The memory stores computer-readable instructions. When the processor executes the computer-readable instructions, the method described in the above embodiment may be executed.

[0208] I understand. Figure 7 The structure shown is for illustration only and may also include Figure 7 More or fewer components than shown, or with Figure 7 Different configurations shown. Figure 7 Each component shown in the figure can be implemented by hardware, software or a combination thereof.

[0209] An embodiment of the present application also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a server, any of the methods described in all the above-mentioned embodiments is implemented. For details, please refer to the description in the above-mentioned method embodiments. To avoid repetition, the detailed description is appropriately omitted here.

[0210] The foregoing description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included within the scope of protection of the present application. It should be noted that similar reference numerals and letters represent similar items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further defined or explained in subsequent figures.

[0211] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A method for evaluating guardrail performance, characterized in that: The method comprises: Acquiring data to be processed collected by a guardrail performance testing device, wherein the data to be processed includes a guardrail displacement of the guardrail performance testing device with respect to a target guardrail, a propulsion distance of the guardrail performance testing device, and a load; The reference protection energy and reference load parameters corresponding to the target guardrail are calculated based on the data to be processed, wherein the reference protection energy is characterized by the energy absorbed by the target guardrail during deformation, wherein the reference load parameters are characterized by yield strength, ultimate load, and breakaway load, and the reference protection energy is obtained by calculating the yield strength, ultimate load, and breakaway load. The calculation process of the reference protection energy includes: The area from 0 to the yield strength is taken as the first stage protection energy. The calculation process of the first stage protection energy is shown in the following formula (2): （2） in, represents the first stage protection energy, represents the guardrail displacement of the monitoring point corresponding to the yield strength, represents the load between 0 and the yield strength, represents yield strength; The area corresponding to the yield strength to the ultimate load is taken as the second-stage protection energy. The calculation process of the second-stage protection energy is shown in the following formula (3): （3） in, represents the second stage protection energy, represents the guardrail displacement of the monitoring point corresponding to the ultimate load, represents the guardrail displacement of the monitoring point corresponding to the yield strength, represents the ultimate load, represents the yield strength, x Indicates a preset guardrail displacement; The area corresponding to the ultimate load to the maximum guardrail displacement is taken as the third-stage protection energy. The calculation process of the third-stage protection energy is shown in the following formula (4): （4） in, represents the third stage protection energy, is the breakaway load The guardrail displacement of the corresponding monitoring point, represents the breakaway load; Adding the first-stage protection energy, the second-stage protection energy, and the third-stage protection energy to obtain the reference protection energy; The reference protection energy is the test reference protection energy, which is the energy that can be absorbed by the guardrail posts and the guardrail panels connected thereto, which are n intermediate posts away from the target guardrail. It is expressed by the following formula (5): （5） Where n represents the number of guardrail posts counted from the middle post of the target guardrail to the side. It represents the energy that can be absorbed by the nth guardrail post and the guardrail board connected to it. represents the energy that can be absorbed by the middle column and the connected guardrail panels of the target guardrail, c represents the coefficient, and e represents the natural constant; It is obtained by the following formula (6): （6） in, Indicates the design protection energy, Indicates the first stage protection energy, Indicates the second stage protection energy, represents the third stage protection energy, u represents the number of guardrail posts counted from the middle post of the target guardrail to one side, v represents the number of guardrail posts counted from the middle post of the target guardrail to one side, the values ​​of u and v are determined by the size of the target guardrail, Q represents the test reference protection energy, Indicates the guardrail post counted as 1 on one side starting from the middle post of the target guardrail; The reference protection energy is the on-site reference protection energy. The protection energy of the guardrail to be tested is obtained by the following formula (7): （7） in, represents the protective energy of the guardrail to be detected, Indicates the energy that can be absorbed by the guardrail post and the guardrail board connected to the guardrail post that is nth farthest from the middle post. Indicates the energy that can be absorbed by the middle column and the guardrail board connected to the guardrail to be tested, It represents the energy that can be absorbed by the guardrail board connected to the first column level on both sides of the middle column of the guardrail to be tested. a represents the guardrail column counted from the middle column of the guardrail to be tested to a on one side. b represents the guardrail column counted from the middle column of the guardrail to be tested to b on one side. represents the on-site reference protection energy; When the load parameters corresponding to the guardrail to be tested do not meet the reference load parameters, the ratio between the protection energy of the guardrail to be tested and the design protection energy is calculated to obtain the protection performance of the guardrail to be tested, so that the guardrail to be tested is maintained based on the protection performance, wherein the design protection energy is represented by the reference protection energy.

2. The method according to claim 1, characterized in that The calculating the reference protection energy and reference load parameters corresponding to the target guardrail according to the data to be processed includes: Taking the maximum load in the data to be processed as the limit load; Calculating a plurality of load-displacement ratios in the data to be processed, and taking the load corresponding to the load-displacement ratio that meets a preset condition as the yield strength; The instantaneous load corresponding to the moment of fracture of the target guardrail is used as the breakaway load, or the instantaneous load corresponding to the maximum guardrail displacement is used as the breakaway load; The reference protection energy is calculated based on the yield strength, ultimate load and breakaway load.

3. The method according to claim 2, characterized in that A load-displacement ratio corresponds to a load corresponding to a preset guardrail displacement, the multiple load-displacement ratios including a first load-displacement ratio, and the first load-displacement ratio is any one of the multiple load-displacement ratios; The first load-displacement ratio is obtained by the following formula (1): K n = （F n -F n-1 ） / x （1） in, K n represents the first load-displacement ratio, F n represents the load corresponding to the displacement of any guardrail, F n-1 represents the load corresponding to the displacement of the previous guardrail, x Indicates a preset advance distance.

4. The method according to claim 2, characterized in that The load corresponding to the load-displacement ratio that meets the preset conditions is used as the yield strength, including: Calculate the average value of t adjacent load-displacement ratios; When the average value is greater than a preset load-displacement threshold and the t load-displacement ratios are all greater than 0, the load corresponding to the load-displacement ratio with the smallest guardrail displacement among the t load-displacement ratios is used as the yield strength.

5. The method according to any one of claims 1 to 4, characterized in that The reference load parameters are expressed as: , ]、[ , ]and[ Q min , +∞], where is the minimum ultimate load in multiple tests on the target guardrail, is the maximum ultimate load, is the minimum yield strength, is the maximum yield strength, Q min It is the minimum test reference protection energy.

6. A device for evaluating guardrail performance, characterized in that: The device is used to perform the method according to claim 1, and the device includes: a data acquisition module configured to acquire data to be processed collected by a guardrail performance testing device, wherein the data to be processed includes a guardrail displacement of a target guardrail by the guardrail performance testing device, a propulsion distance, and a load of the guardrail performance testing device; a parameter calculation module configured to calculate a reference protection energy and a reference load parameter corresponding to the target guardrail based on the data to be processed, wherein the reference protection energy is characterized by the energy absorbed by the target guardrail during deformation; The performance evaluation module is configured to calculate the ratio between the protective energy of the guardrail to be detected and the design protective energy when the load parameters corresponding to the guardrail to be detected do not meet the reference load parameters, and obtain the protective performance of the guardrail to be detected, so as to maintain the guardrail to be detected based on the protective performance, wherein the design protective energy is represented by the reference protective energy.

7. An electronic device, characterized in that: include: processor, memory, and bus; The processor is connected to the memory via the bus, the memory stores a computer program, and when the computer program is executed by the processor, the method according to any one of claims 1 to 5 can be implemented.

8. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, which, when executed, can implement the method according to any one of claims 1 to 5.

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