Bridge member anti-icing performance testing method and device

Abstract

The application provides a bridge component anti-icing performance test method and equipment, and the system realizes multivariate simulation test on the bridge cable icing process through integration of an adjustable angle support, a test piece refrigeration bin, an ice water control module and an automatic spraying module. The method comprises the following steps: recording initial parameters of the test piece, establishing a simulated freezing rain environment, performing a cyclic spraying test, measuring icing state parameters, and calculating and evaluating a comprehensive anti-icing index based on an equivalent icing amount, an anti-icing delay coefficient and an environmental correction factor. The application can solve the technical problems of low test efficiency, high cost and lack of evaluation method in the prior art.

Description

Technical Field

[0001] This invention relates to the field of bridge component testing technology, specifically to a method and equipment for testing the anti-icing performance of bridge components. Background Technology

[0002] Bridge cables are the main load-bearing structure of suspension bridges and cable-stayed bridges. However, because they are exposed to wind, rain, humidity and polluted air for a long time, they are easily damaged by clothing. In engineering practice, high-density polyethylene (HDPE) sleeves are usually installed on the outside of the cables.

[0003] Due to its climate, the suspended cable-stayed bridge cables and their HDPE sleeves in Central China are constantly exposed to strong winds. After rain or snow, the high humidity and fluctuating temperatures around 0°C make them highly susceptible to icing. Increased wind speed further lowers the temperature, accelerating the icing process. After the rain or snow, as temperatures rise, the cables vibrate slightly due to passing vehicles and wind, causing icing to fall from the cables and sleeves, posing a significant safety hazard to vehicles and pedestrians. Furthermore, once the cables of a cable-stayed bridge freeze, eccentric icing easily forms on their surface, changing the cable's cross-section from circular to non-circular. Under wind excitation, this generates low-frequency, high-amplitude vibrations known as cable-stayed cable icing galloping. This can induce cracking in the external PE sleeves of the cables, leading to corrosion damage to the cables and anchoring system, altering aerodynamic characteristics and the bridge's wind-induced response, and threatening the structural safety of the bridge.

[0004] Because cable-stayed bridge icing is a probabilistic natural phenomenon that varies depending on factors such as climate and meteorological conditions in different regions, solutions to this problem are still in the experimental research stage both domestically and internationally. Currently, the performance verification of anti-icing materials relies on large-scale environmental test chambers or actual bridge testing. Environmental test chamber testing is inefficient and costly; actual bridge testing requires specific weather conditions, has a long testing cycle, is difficult, involves high construction costs, and it is difficult to standardize test parameters (temperature, angle, etc.).

[0005] Meanwhile, existing tests lack the ability to perform multivariate collaborative analysis, making it impossible to quantitatively evaluate the anti-icing performance of coatings at low temperatures, different tilt angles, and different environments. For example, traditional methods have difficulty monitoring the correlation between icing rate and icing morphology.

[0006] Therefore, how to achieve automated, low-cost, and efficient evaluation of the anti-icing performance of bridge components is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention proposes a method and equipment for testing the anti-icing performance of bridge components, thereby solving the technical problems of low efficiency and high cost in evaluating anti-icing performance and the lack of multivariate collaborative analysis capabilities in existing technologies.

[0008] The technical solution adopted in this invention is to construct an adjustable-angle support, a low-temperature freezer environment, and a spraying system to achieve multivariate, high-fidelity simulation testing of the icing process of bridge cables, providing a reliable experimental platform for evaluating the performance of anti-icing coatings.

[0009] In a first feasible approach, a method for testing the anti-icing performance of bridge components includes the following steps:

[0010] Record the initial parameters of the test specimen, including: record the original weight and initial pipe diameter of the test specimen before icing;

[0011] A simulated freezing rain environment was established based on the actual working conditions of bridge components;

[0012] In the simulated freezing rain environment, the cyclic spraying test was repeatedly performed according to a preset number of cycles;

[0013] Obtain the state parameters of the test specimen after spraying and icing;

[0014] A comprehensive anti-icing index is generated based on the aforementioned state parameters;

[0015] The anti-icing performance of the current test specimen is evaluated based on the comprehensive anti-icing index.

[0016] Furthermore, a simulated freezing rain environment was established based on the actual working conditions of bridge components, including:

[0017] The test specimen is fixed at a set angle on the specimen support inside the specimen cooling chamber;

[0018] Set the temperature of the specimen cooling chamber to a preset sub-zero temperature value and pre-cool it for a preset time.

[0019] The ice water used to simulate freezing rain was maintained at 0-2℃.

[0020] Furthermore, the cyclic spraying test is repeated according to a preset number of cycles, including:

[0021] Set the duration of a single spraying session to 5 minutes, the spraying interval to 20 minutes, the total number of cycles to T, and initialize the current cycle number t to 1.

[0022] Turn on the water pump and drain switch to drain the residual water in the spray test pipeline;

[0023] Turn off the drain switch and turn on the spray system according to the single spray duration to spray the ice water onto the surface of the test specimen.

[0024] Delay according to the spray interval time;

[0025] After every 5 spraying cycles, a surface image of the test specimen was acquired.

[0026] If t ≤ T, the number of cycles is incremented by one, and the process returns to the step of turning on the water pump and the drain switch;

[0027] If t > T, acquire a surface image of the test specimen and terminate the spraying process.

[0028] Furthermore, obtaining the state parameters of the test specimen after spraying and icing includes:

[0029] The freezing rate index is determined based on the surface image of the test specimen;

[0030] The final ice-covered length is determined based on the last image in the surface image;

[0031] Obtain the measured surface temperature of the specimen and the specimen placement angle;

[0032] Remove the test specimen from the specimen cooling chamber and record its weight and pipe diameter after icing.

[0033] The icing weight and icing thickness are calculated based on the original weight and initial pipe diameter.

[0034] Furthermore, the freezing rate index is determined based on the surface image of the test specimen, including:

[0035] Edge detection and morphological processing are performed on the acquired surface images to generate a binarized ice-covered contour;

[0036] When the longitudinal projection length of the contour exceeds the threshold for the first time, record the current number of sprays;

[0037] The freezing delay coefficient is calculated based on the number of sprays, and serves as an indicator of the freezing rate.

[0038]

[0039] Where K represents the icing delay coefficient, and N represents the number of spray cycles required for noticeable ice formation on the test specimen surface. This indicates the number of spray cycles required for the uncoated reference specimen to first freeze. denoted by , where t represents the attenuation constant and t represents the number of spray cycles.

[0040] Furthermore, determining the final ice-covered length based on the last image in the surface image includes:

[0041] A morphological thinning operation is performed on the binarized ice-covered contour of the last image, and the length of the central axis of the longest connected region is extracted as the final ice-covered length.

[0042] Furthermore, a comprehensive anti-icing index is generated based on the aforementioned state parameters to comprehensively evaluate the anti-icing effect of the test specimen, including:

[0043] Calculate the equivalent ice cover using the spatial dimension integration formula:

[0044]

[0045] Where Q represents the equivalent icing amount, This indicates the icing quality of the uncoated reference specimen. This indicates the icing thickness of the uncoated reference specimen. The value represents the ice-covered length of the uncoated reference specimen, m represents the ice mass of the test specimen, d represents the ice thickness of the test specimen, and L represents the ice-covered length of the test specimen. , and These represent the weighting coefficients for the ice-covered mass, ice-covered thickness, and ice-hanging length of the test specimen, respectively.

[0046] Calculate the environmental correction factor based on the measured surface temperature of the specimen and the specimen placement angle:

[0047]

[0048] in, Indicates the environmental correction factor. This indicates the measured temperature on the surface of the specimen. Indicates the angle at which the specimen is placed. express, Indicates the reference angle;

[0049] A comprehensive anti-icing index is generated based on the anti-icing index calculation formula:

[0050]

[0051] Where S represents the comprehensive anti-icing index, K represents the icing delay coefficient, and Q represents the equivalent icing amount. This represents the environmental correction factor.

[0052] Furthermore, the anti-icing performance of the current test specimen is evaluated based on the comprehensive anti-icing index, including:

[0053] If the comprehensive anti-icing index is greater than the set value of 0.85, the current test specimen is judged to have first-level anti-icing performance, corresponding to a long-lasting anti-icing coating, which is suitable for bridges in extremely cold regions.

[0054] If the comprehensive anti-icing index is between 0.85 and 0.7, the current test specimen is judged to have a level 2 anti-icing performance, which meets the conventional anti-icing requirements and is suitable for most freezing rain areas;

[0055] If the comprehensive anti-icing index is below 0.7, the current test specimen is judged to be in the improvement stage, and the coating formula needs to be optimized or the number of application coats needs to be increased.

[0056] In conjunction with the first feasible method, in the second feasible method, a bridge component anti-icing performance testing device includes a specimen testing module, a specimen cooling chamber, a specimen support, an ice water control module, and an automatic spraying module, characterized in that:

[0057] The specimen detection module is used to record the initial parameters of the test specimen and obtain the state parameters of the test specimen after spraying and icing.

[0058] The specimen cooling chamber is used to establish a simulated freezing rain environment based on the actual working conditions of bridge components.

[0059] The specimen cooling chamber is provided with at least one set of specimen supports, which are used to place test specimens.

[0060] The ice water control module is used to maintain the ice water at 0℃-2℃;

[0061] The automatic spraying module is used to repeatedly perform cyclic spraying tests according to a preset number of cycles.

[0062] Furthermore, the automatic sprinkler module includes a water pump and a sprinkler device. The water pump is connected to the chilled water control module and the sprinkler device respectively through pipelines, and is used to transport chilled water from the chilled water control module to the sprinkler device.

[0063] The spraying device includes an atomizing nozzle, a support sleeve, and a spraying pipeline. The support sleeve is fixed to the top of the specimen cooling chamber. The spraying pipeline passes through the support sleeve, with one end connected to a water pump. A continuous slit is opened at the bottom of the support sleeve along its length. The atomizing nozzle is fixedly connected to the spraying pipeline in the direction of the continuous slit.

[0064] The end of the spray pipe away from the water pump is connected to a drain switch, and the drain switch is fixedly connected to the outside of the specimen cooling chamber.

[0065] As can be seen from the above technical solution, the beneficial technical effects of the present invention are as follows:

[0066] 1. By integrating an adjustable angle support, a specimen cooling chamber, and a spray system, the meteorological conditions of freezing rain, high humidity, and low temperature are reproduced in a laboratory environment, which improves the problems of long testing cycles, high difficulty, and high construction costs of existing testing methods.

[0067] 2. An automatic cycle of 5-minute spraying followed by a 20-minute interval was set. The ice formation was recorded every 5 sprays, and the freezing speed index and ice formation parameters were automatically extracted by the algorithm. This further reduced the experimental cost and lowered the complexity of operation and maintenance as well as the labor cost.

[0068] 3. A complete set of quantitative evaluation indicators was established to quantitatively assess the anti-icing performance of bridge components at low temperatures and different inclination angles, thus achieving an accurate evaluation of the performance of anti-icing coatings. Attached Figure Description

[0069] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0070] Figure 1 This is a system structure diagram of Embodiment 1 of the present invention;

[0071] Figure 2 This is a structural diagram of the specimen support in Embodiment 1 of the present invention;

[0072] Figure 3 This is a structural diagram of the spray device according to Embodiment 1 of the present invention;

[0073] Figure 4 This is a diagram showing the test conditions for the freezing test in Embodiment 2 of the present invention;

[0074] Figure 5 This is a configuration diagram of the HDPE specimen in Embodiment 2 of the present invention;

[0075] Figure 6 This is a flowchart of the method in Embodiment 2 of the present invention;

[0076] Figure 7 This is an evaluation diagram of the anti-icing performance of Embodiment 2 of the present invention;

[0077] Figure label:

[0078] 1-Specimen cooling chamber; 2-Ice water control module;

[0079] 3-Automatic sprinkler module, 31-Water pump, 32-Sprinkler device, 321-Atomizing nozzle, 322-Support sleeve, 323-Sprinkler pipeline, 324-Drain switch;

[0080] 4-Specimen support, 41-Horizontal bar, 411-Upper horizontal bar, 412-Lower horizontal bar, 42-Vertical bar, 43-Tee connector, 44-Tee connector;

[0081] 5 - Test specimen; 6 - Four-way connector. Detailed Implementation

[0082] The embodiments of the technical solution of the present invention will now be described in detail with reference to the accompanying drawings. These embodiments are merely illustrative of the technical solution of the present invention and are therefore intended to limit the scope of protection of the present invention.

[0083] It should be noted that, unless otherwise stated, the technical or scientific terms used in this application should have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0084] Example 1

[0085] This embodiment provides a bridge component anti-icing performance testing system. The working principle of Embodiment 1 is explained in detail below:

[0086] The system structure diagram of this embodiment is as follows: Figure 1 As shown, it includes a specimen cooling chamber 1, an ice water control module 2, and an automatic spray module 3.

[0087] The specimen cooling chamber 1 employs a dual-compressor cooling system to provide and maintain the sub-zero temperature environment required for testing. The temperature of the specimen cooling chamber 1 is controlled electronically, allowing for temperature control from -30℃ to 10℃ and real-time display of the internal temperature via a control panel.

[0088] In this embodiment, three sets of specimen supports 4 are provided in the specimen cooling chamber 1. The specimen supports 4 are used to place the test specimens 5 at an adjustable angle.

[0089] The structural diagram of the specimen support is as follows: Figure 2 As shown, it includes a horizontal bar 41, a vertical bar 42, a T-joint 43, and an adjustable support leg 44.

[0090] The crossbar 41 includes an upper crossbar 411 and a lower crossbar 412 arranged in parallel, and vertical bars 42 are connected to both sides of the crossbar 41 through a T-joint 43.

[0091] Two sets of tee connectors 43 for connecting the test specimen are symmetrically arranged between the upper crossbar 411 and the lower crossbar 412, and the test specimen 5 is fixed between the upper crossbar 411 and the lower crossbar 412.

[0092] The adjustable support legs 44 are symmetrically installed at both ends of the upper crossbar 411 and are used to adjust the levelness of the specimen support 4 frame.

[0093] The ice water control module 2 maintains the ice water used for spraying at 0℃-2℃ and can monitor the water temperature in real time. The six sides of the chamber are made of PU polyurethane, a commonly used insulation material in freezers and refrigerators, enabling 6-10 hours of freezing without thawing and 48-72 hours of 0-8℃ refrigeration, sufficient to cover the time requirements of the experimental procedure. The ice water control module 2 is equipped with a thermometer for real-time monitoring of the internal temperature.

[0094] The automatic sprinkler module 3 includes a water pump 31 and a sprinkler device 32. In this embodiment, the water pump 31 is a single-phase self-priming clean water pump with a rated flow rate of 1.5 m³ / h. 3 / h, maximum flow rate 4m 3 The pump has a capacity of 0.75kW and a water valve at the outlet of the pump 31, which is used to manually adjust the water flow rate in an emergency.

[0095] The water pump 31 is connected to the chilled water control module 2 and the spray device 32 via pipelines, and is used to transport chilled water from the chilled water control module 2 to the spray device 32. An opening is made in the side wall of the specimen cooling chamber 1 to facilitate the passage of the spray device 32.

[0096] The structural diagram of the spray device is as follows: Figure 3 As shown, the device includes an atomizing nozzle 321, a support sleeve 322, and a spray pipe 323. The spray device 321 is used to evenly spray ice water onto the surface of the specimen. The support sleeve 322 is fixed to the top of the specimen cooling chamber 1. The spray pipe 323 passes through the support sleeve 322, with one end connected to a water pump 31. The bottom of the support sleeve 322 has a continuous slit along its length. The atomizing nozzle 321 is fixedly connected to the spray pipe 322 in the direction facing the continuous slit. The end of the spray pipe 323 away from the water pump 31 is connected to a drain switch 324, which is fixedly connected to the outside of the specimen cooling chamber 1.

[0097] In this embodiment, the spray pipe 323 of the spraying device 32 has three branches to ensure more uniform spraying on the surface of the specimen. For example... Figure 1 As shown, a four-way connector 6 is provided between the spray pipe 323 and the water pump 31 to divert ice water to multiple spray areas.

[0098] In this embodiment, by integrating an adjustable angle support, a specimen cooling chamber, and a spray system, the meteorological conditions of freezing rain, high humidity, and low temperature are reproduced in a laboratory environment, thus improving the problems of long testing cycles, high difficulty, and high construction costs in existing testing methods.

[0099] Example 2

[0100] In conjunction with Example 1, Example 2 tests the anti-icing performance of bridge components using the system provided in Example 1.

[0101] The variables considered in setting up the icing test conditions include test temperature, placement angle, and cleanliness. The test parameters for each variable are shown below:

[0102] ① Matrix materials: HDPE, steel.

[0103] ②Temperature: -9℃, -25℃.

[0104] ③ Placement angle: 0°, 45°.

[0105] ④ Cleanliness level: Dust and dirt, washed with soapy water.

[0106] Therefore, this icing test included 16 operating conditions, such as... Figure 4 As shown, there are 8 HDPE and 8 steel structures. The effects of environmental temperature, component angle, and surface cleanliness on the icing performance of cables and steel components are analyzed. The performance of various commercially available anti-icing coatings is studied, and corresponding construction techniques are proposed based on the test results.

[0107] In this embodiment, the variables considered in the design of the icing test specimens include four categories: substrate material, anti-icing coating, coating method, and number of coating coats. In this embodiment, four commercially available coatings with anti-icing and hydrophobic functions, while also meeting the engineering production capacity requirements, were selected as the anti-icing coating. The test parameters for each variable are shown below:

[0108] ① Matrix materials: HDPE, steel.

[0109] ② Anti-icing coating: Deqian WR 620, Shuneng DSAN-S2001-DL(III), Zhisheng ZS-611, Huiyan inorganic nano water-based coating.

[0110] ③ Coating method: brushing, spraying.

[0111] ④ Number of coats: 2, 4, or 6.

[0112] The test specimens were numbered according to the following code: "Substrate Code - Coating Code - Number of Coating Coats Code - Coating Process Code", where:

[0113] Substrate codes: H—HDPE; G—steel.

[0114] Coating codes: D—Deqian WR 620 superhydrophobic coating. S—Shuneng DSAN-S2001-DL(III) superhydrophobic, self-cleaning, and anti-icing coating. Z—Zhisheng ZS-611 anti-icing and snow coating. H—Huiyan inorganic nano-waterborne coating.

[0115] Coating pass codes: b1—2 passes; b2—4 passes; b3—6 passes.

[0116] Coating process codes: c1—brush coating; c2—spray coating.

[0117] This anti-icing test included 25 HDPE specimens: one original surface specimen and 24 anti-icing coating specimens. Six specimens were coated with each of the four different anti-icing materials. By comparing the anti-icing effects of various commercially available anti-icing coatings under different coat numbers and application methods (brush or spray), the anti-icing coating application process for HDPE sheaths was determined and proposed. The test configuration of the HDPE specimens is as follows: Figure 5 As shown.

[0118] According to the test conditions, the HDPE specimens were made of Φ63mm×4.7mm×600mm round pipes. The construction process for the specimens was as follows: material cutting—sanding—spraying / brushing anti-icing paint. After the specimens were cut to size, the surface was sanded with 80-grit sandpaper. After cleaning the surface residue, the anti-icing material was sprayed with a spray gun or brushed on.

[0119] Similarly, this icing test included 25 steel specimens: one original surface specimen and 24 anti-icing coating specimens. Six specimens were coated with each of the four different anti-icing materials. By comparing the anti-icing effects of various commercially available anti-icing coatings under different coating coats and application methods (brush or spray), the construction process for anti-icing coatings on bridge steel structures was determined and proposed. The test configuration for the steel specimens is shown in Table 2 and will not be elaborated further here.

[0120] According to the test conditions, the steel pipe specimens were Φ60mm×2mm×600mm round pipes made of Q235B steel. The construction process for the specimens was as follows: material preparation—sandblasting—spraying anti-corrosion paint—spraying / brushing anti-icing paint. After the specimens were cut to size, the surface of the steel pipes was sandblasted to Sa2.5 grade. The anti-corrosion paint for the steel pipe specimens adopted the protective coating system corresponding to the JC3 corrosion level (medium) in the "Technical Conditions for Anti-corrosion Coating of Steel Structures for Highway Bridges" (JT / T 722-2023), with a total dry film thickness of 260μm. The primer was epoxy zinc-rich primer with a dry film thickness of 60μm. The intermediate coating was epoxy micaceous iron oxide paint with a dry film thickness of 120μm. The topcoat was acrylic polyurethane topcoat with a dry film thickness of 80μm. After the anti-corrosion paint was applied, the anti-icing material was sprayed using a spray gun or brushed on.

[0121] In this embodiment, furthermore, test specimens are selected sequentially according to the test configuration table for HDPE specimens and the test configuration table for steel specimens, and performance tests are carried out sequentially according to the icing test conditions. A flowchart of a method for testing the anti-icing performance of bridge components is shown below. Figure 6 As shown, each round of testing includes the following steps:

[0122] Record the initial parameters of the test specimen, including: the parameters of its anti-icing coating and substrate material, the original weight before icing and the initial pipe diameter before icing.

[0123] Establish a simulated freezing rain environment, including:

[0124] The test specimen is fixed at a set angle on the specimen support inside the specimen cooling chamber.

[0125] The temperature of the specimen cooling chamber was set to -10℃ and pre-cooled for two hours to ensure that its surface temperature was below 0℃.

[0126] The chilled water in the chilled water control module is maintained at 0~2℃.

[0127] The spray duration is set to 5 minutes per cycle, with a spray interval of 20 minutes. The cyclic spray test is repeated 50 times according to a preset number of cycles, including:

[0128] Turn on the water pump and drain switch to drain residual water from the pipeline before each spraying session;

[0129] Turn off the drain switch and turn on the spray system according to the set time to spray the ice water in the ice water control module onto the surface of the test specimen.

[0130] In the cyclic spray test, after every 5 spray cycles, a surface image of the test specimen is captured by a camera installed inside the specimen cooling chamber.

[0131] In this embodiment, an automatic cycle of 5-minute spraying followed by a 20-minute interval is set. The image acquisition system records the icing morphology every 5 sprays, and the algorithm automatically extracts the icing speed index and icing morphology parameters, further reducing experimental costs and lowering the complexity of operation and maintenance and labor costs.

[0132] Measuring the state parameters of the test specimen after it has been iced includes:

[0133] Based on the surface images of the test specimen, the freezing speed index and the final ice-covered length are determined, including: performing edge detection and morphological processing on the sequence of the collected surface images to generate a binary ice-covered profile.

[0134] When the longitudinal projection length of the profile first exceeds the threshold L_th (≥5mm), the current spraying number is recorded as N, which represents the number of sprayings when obvious ice formation appears on the surface of the test specimen.

[0135] After completing the preset number of spraying cycles, perform morphological thinning on the last image and extract the length of the central axis of the longest connected region as the final ice-covered length L.

[0136] The surface temperature of the test specimen was monitored using an infrared thermal imager, and the angle at which the specimen was placed was also obtained.

[0137] The test specimen was removed from the specimen cooling chamber, and its weight m1 and pipe diameter d1 after icing were recorded.

[0138] The icing weight is calculated based on the original weight and initial pipe diameter: m = m1 − m0 and the icing thickness is d = (d1 − d0) / 2.

[0139] The anti-icing effect of the test specimen is comprehensively evaluated based on the state parameters, and a comprehensive anti-icing index is output, including:

[0140] Calculate the equivalent ice cover using the spatial dimension integration formula:

[0141]

[0142] Where Q represents the equivalent icing amount, This indicates the icing quality of the uncoated reference specimen. This indicates the icing thickness of the uncoated reference specimen. The value represents the ice-covered length of the uncoated reference specimen, m represents the ice mass of the test specimen, d represents the ice thickness of the test specimen, and L represents the ice-covered length of the test specimen. , and These represent the weighting coefficients for the icing quality, icing thickness, and icing length of the test specimen, respectively, in this embodiment. , and Take values ​​of 0.4, 0.4, and 0.2 respectively.

[0143] The freezing delay coefficient is calculated based on the number of spray cycles required when obvious ice formation appears on the surface of the test specimen, and is used as an indicator of freezing rate.

[0144]

[0145] Where K represents the icing delay coefficient, and N represents the number of spray cycles required for noticeable ice formation on the test specimen surface. This indicates the number of spray cycles required for the uncoated reference specimen to first freeze. The constant represents the attenuation constant, and t represents the number of spray cycles;

[0146] The decay rate constant representing the anti-icing performance of the coating is obtained by fitting the icing growth curve:

[0147]

[0148] in, The ice thickness is calculated for every 5 sprays. The icing thickness at the initial freezing point is given. In this embodiment, four types of coatings are used, with attenuation constants set as follows:

[0149] Zhisheng ZS-611: 0.005; Huiyan Inorganic Nano Waterborne Coating: 0.002; Shuneng DSAN-S2001-DL(III): 0.003; Deqian WR 620: 0.006.

[0150] Calculate the environmental correction factor based on the measured surface temperature of the specimen and the specimen placement angle:

[0151]

[0152] in, Indicates the environmental correction factor. This indicates the measured temperature on the surface of the specimen. Indicates the angle at which the specimen is placed. express, This represents the reference angle; it is customized according to the test standard, with 45° as the reference. At this time, the correction factor = 1, because it is the typical inclination angle of a cable-stayed bridge. It is used to normalize the ice adhesion rate at any angle θ to the 45° reference condition, eliminating the influence of the angle on the amount of ice and water adhesion.

[0153] A comprehensive anti-icing index is generated based on the anti-icing index calculation formula:

[0154]

[0155] Where S represents the comprehensive anti-icing index, K represents the icing delay coefficient, and Q represents the equivalent icing amount. This represents the environmental correction factor.

[0156] The anti-icing performance of the current test specimen is evaluated based on the comprehensive anti-icing index, according to... Figure 7 The anti-icing performance evaluation shown classifies the test specimens and outputs the initial parameters and anti-icing performance evaluation of the test specimens. In this embodiment, by establishing a complete quantitative evaluation index, the anti-icing performance of bridge components at low temperature and different inclination angles is quantitatively evaluated, thus realizing an accurate evaluation of the anti-icing coating performance.

[0157] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

Claims

1. A method for testing the anti-icing performance of bridge components, characterized in that, Includes the following steps: Record the initial parameters of the test specimen, including: record the original weight and initial pipe diameter of the test specimen before icing; A simulated freezing rain environment was established based on the actual working conditions of bridge components; In the simulated freezing rain environment, the cyclic spraying test was repeatedly performed according to a preset number of cycles; Obtain the state parameters of the test specimen after spraying and icing; A comprehensive anti-icing index is generated based on the aforementioned state parameters, including: Calculate the equivalent ice cover using the spatial dimension integration formula: Where Q represents the equivalent icing amount, This indicates the icing quality of the uncoated reference specimen. This indicates the icing thickness of the uncoated reference specimen. The value represents the ice-covered length of the uncoated reference specimen, m represents the ice mass of the test specimen, d represents the ice thickness of the test specimen, and L represents the ice-covered length of the test specimen. , and These represent the weighting coefficients for the ice-covered mass, ice-covered thickness, and ice-hanging length of the test specimen, respectively. Calculate the environmental correction factor based on the measured surface temperature of the specimen and the specimen placement angle: in, Indicates the environmental correction factor. This indicates the measured temperature on the surface of the specimen. Indicates the angle at which the specimen is placed. express, Indicates the reference angle; A comprehensive anti-icing index is generated based on the anti-icing index calculation formula: Where S represents the comprehensive anti-icing index, K represents the icing delay coefficient, and Q represents the equivalent icing amount. Indicates the environmental correction factor; The anti-icing performance of the current test specimen is evaluated based on the comprehensive anti-icing index, including: If the comprehensive anti-icing index is greater than the set value of 0.85, the current test specimen is judged to have first-level anti-icing performance, corresponding to a long-lasting anti-icing coating, which is suitable for bridges in extremely cold regions. If the comprehensive anti-icing index is between 0.85 and 0.7, the current test specimen is judged to have a level 2 anti-icing performance, which meets the conventional anti-icing requirements and is suitable for most freezing rain areas; If the comprehensive anti-icing index is below 0.7, the current test specimen is judged to be in the improvement stage, and the coating formula needs to be optimized or the number of application coats needs to be increased.

2. The method for testing the anti-icing performance of bridge components according to claim 1, characterized in that, A simulated freezing rain environment was established based on the actual working conditions of bridge components, including: The test specimen is fixed at a set angle on the specimen support inside the specimen cooling chamber; Set the temperature of the specimen cooling chamber to a preset sub-zero temperature value and pre-cool it for a preset time. The ice water used to simulate freezing rain was maintained at 0-2℃.

3. The method for testing the anti-icing performance of bridge components according to claim 2, characterized in that, The cyclic spraying test is repeated according to a preset number of cycles, including: Set the duration of a single spraying session to 5 minutes, the spraying interval to 20 minutes, the total number of cycles to T, and initialize the current cycle number t to 1. Turn on the water pump and drain switch to drain the residual water in the spray test pipeline; Turn off the drain switch and turn on the spray system according to the single spray duration to spray the ice water onto the surface of the test specimen. Delay according to the spray interval time; After every 5 spraying cycles, a surface image of the test specimen was acquired. If t ≤ T, the number of cycles is incremented by one, and the process returns to the step of turning on the water pump and the drain switch; If t > T, acquire a surface image of the test specimen and terminate the spraying process.

4. The method for testing the anti-icing performance of bridge components according to claim 3, characterized in that, Obtain the state parameters of the test specimen after spraying and icing, including: The freezing rate index is determined based on the surface image of the test specimen; The final ice-covered length is determined based on the last image in the surface image; Obtain the measured surface temperature of the specimen and the specimen placement angle; Remove the test specimen from the specimen cooling chamber and record its weight and pipe diameter after icing. The icing weight and icing thickness are calculated based on the original weight and initial pipe diameter.

5. The method for testing the anti-icing performance of bridge components according to claim 4, characterized in that, The freezing rate index is determined based on the surface image of the test specimen, including: Edge detection and morphological processing are performed on the acquired surface images to generate a binarized ice-covered contour; When the longitudinal projection length of the contour exceeds the threshold for the first time, record the current number of sprays; The freezing delay coefficient is calculated based on the number of sprays, and serves as an indicator of the freezing rate. Where K represents the icing delay coefficient, and N represents the number of spray cycles required for noticeable ice formation on the test specimen surface. This indicates the number of spray cycles required for the uncoated reference specimen to first freeze. denoted by , where t represents the attenuation constant and t represents the number of spray cycles.

6. The method for testing the anti-icing performance of bridge components according to claim 5, characterized in that, Determining the final ice-covered length based on the last image in the surface image includes: A morphological thinning operation is performed on the binarized ice-covered contour of the last image, and the length of the central axis of the longest connected region is extracted as the final ice-covered length.

7. A bridge component anti-icing performance testing device, applied to the bridge component anti-icing performance testing method as described in any one of claims 1-6, comprising a specimen testing module, a specimen cooling chamber, a specimen support, an ice water control module, and an automatic spraying module, characterized in that: The specimen detection module is used to record the initial parameters of the test specimen and obtain the state parameters of the test specimen after spraying and icing. The specimen cooling chamber is used to establish a simulated freezing rain environment based on the actual working conditions of bridge components. The specimen cooling chamber is provided with at least one set of specimen supports, which are used to place test specimens. The ice water control module is used to maintain the ice water at 0℃-2℃; The automatic spraying module is used to repeatedly perform cyclic spraying tests according to a preset number of cycles.

8. The anti-icing performance testing device for bridge components according to claim 7, characterized in that, The automatic sprinkler module includes a water pump and a sprinkler device. The water pump is connected to the chilled water control module and the sprinkler device through pipelines, and is used to transport chilled water from the chilled water control module to the sprinkler device. The spraying device includes an atomizing nozzle, a support sleeve, and a spraying pipeline. The support sleeve is fixed to the top of the specimen cooling chamber. The spraying pipeline passes through the support sleeve, with one end connected to a water pump. A continuous slit is opened at the bottom of the support sleeve along its length. The atomizing nozzle is fixedly connected to the spraying pipeline in the direction of the continuous slit. The end of the spray pipe away from the water pump is connected to a drain switch, and the drain switch is fixedly connected to the outside of the specimen cooling chamber.

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