A testing device and method for the water damage resistance performance between layers of bridge deck pavement structure

Abstract

The present invention relates to the technical field of bridge pavement, and specifically to a testing device and method for the water damage resistance performance between layers of a bridge deck pavement structure. The testing device provided in the present application realizes the quantitative evaluation of the water damage resistance performance between layers of a bridge deck pavement structure under the conditions of water-temperature-load coupling. More importantly, the testing device and the evaluation method provided by the present invention can be used to accurately detect and evaluate the bonding conditions between layers of the bridge deck pavement structure, so that the water damage resistance performance between layers of the pavement can be objectively grasped, and then the selection of adhesive layer materials, pavement construction and maintenance can be guided in a targeted manner, which can effectively prevent the occurrence or further development of bonding diseases between layers of the pavement, and is of great significance for improving the service performance and service life of the bridge deck pavement structure.

Description

Technical Field

[0001] The invention relates to the technical field of bridge pavement, and in particular to a device and method for testing the water damage resistance performance between layers of a bridge deck pavement structure. Background Art

[0002] The interlayer bonding performance of the bridge deck pavement structure is one of the important factors affecting the service life of the bridge deck pavement. If the interlayer bonding performance is poor, it will weaken the integrity of the pavement system and reduce the bearing capacity of the structural layer. In areas where there is interlayer shear stress, early defects such as crescent-shaped push cracks are prone to occur, and as the service time increases, serious defects such as displacement and congestion may even occur, which seriously affect the service performance of the bridge deck pavement and reduce its traffic capacity.

[0003] A large number of engineering practices have shown that interlayer diseases of bridge deck pavement are caused under the coupling conditions of strong alkaline water, temperature and load. The specific mechanism is as follows: water enters the interlayer of the structural layer, dissolves various substances at high temperature to form a strong alkaline solution, and the formed strong alkaline solution continuously scours the interlayer of the structure through the wheel load until the interlayer is damaged. The selection, design and construction of interlayer bonding materials and paving mixtures can affect whether interlayer damage occurs and how early it occurs. Therefore, accurate detection and evaluation of the water damage resistance of the interlayer of the pavement structure is of great significance for the selection, construction and maintenance of the bonding materials and paving materials of the pavement layer, which can prevent the occurrence or further development of interlayer bonding diseases of the pavement layer and greatly improve the service performance and service life of the bridge deck pavement structure.

[0004] Through investigation, it was found that among the existing testing technologies related to the resistance of asphalt pavement to water damage, the current "Test Procedures for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011) proposed the immersion Marshall stability test and freeze-thaw splitting test of asphalt mixtures. The adhesion tests such as the boiling method and water immersion method for the adhesion of the aggregate-asphalt interface can characterize the water stability of the mixture and the resistance to water stripping of aggregate-asphalt to a certain extent, but cannot simulate the actual working conditions of the layers being eroded by dynamic water. On this basis, the improvement directions can be roughly divided into two types: the first is to improve the test device, such as Chinese patent document CN113176203 A (application number 202110339519.2), which discloses an interlayer bonding strength test system and provides a new test device for realizing shear and pull-out experiments; the second is to optimize the parameters in the shear and pull-out test process, such as Chinese patent document CN 117232994A (application number 202311119603.9), which comprehensively considers the environment and usage factors to adjust the various parameters in the shear performance test process. Although the specimens are immersed in water, frozen and thawed in combination with the service conditions before the test, these treatments are far from the actual working conditions between the pavement structure layers, and cannot accurately correspond to the actual working conditions of the bridge deck. The state between the pavement layers cannot be quantified, and it is difficult to accurately evaluate the water damage resistance between the pavement structure layers. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies of the above-mentioned prior art and to provide a testing device and method for the interlayer water damage resistance of bridge deck pavement structural layers. The testing device can simultaneously provide three conditions, namely, strong alkaline water, temperature and load, so that the three conditions are coupled to test the bonding state, accurately simulating the actual use conditions of the bridge deck. At the same time, the method provides a specific evaluation method for the bonding state under the above-mentioned conditions, so that technical personnel in this field can accurately know the performance of the structural layer based on the test results.

[0006] In order to achieve the above technical effects, the present invention adopts the following technical solutions:

[0007] A testing device for the water damage resistance performance between layers of a bridge deck pavement structure, comprising:

[0008] A flushing container, the flushing container comprising a transparent cylinder and an extrusion positioning assembly inside the transparent cylinder, the left and right ends of the transparent cylinder are open and provided with a cover plate, the upper and lower parts of the transparent cylinder are respectively provided with a first flushing port and a second flushing port, and the transparent cylinder is provided with an extrusion positioning assembly that can move in a horizontal direction;

[0009] The dynamic water flushing system comprises a dynamic water storage tank, an air compressor, a vacuum pump and a pressure gauge. The dynamic water storage tank is connected to the first flushing port and the second flushing port through the air compressor and the vacuum pump respectively. The pressure gauge is arranged on the dynamic water storage tank.

[0010] A temperature control system includes a heating device, a cooling device and a temperature control device. The heating device and the cooling device are respectively arranged in a dynamic water storage tank. The temperature control device includes a temperature sensor and a temperature controller. The temperature sensor is arranged in the dynamic water storage tank. The temperature controller is respectively electrically connected to the temperature sensor, the heating device and the cooling device. The temperature controller is used to receive the temperature measured by the temperature sensor and control the heating device and the cooling device according to the measured temperature.

[0011] Preferably, the extrusion positioning assembly includes two symmetrically arranged positioning members, the positioning members include a positioning plate and a push handle, and the push handle is located on a side of the positioning plate away from the symmetry plane.

[0012] Preferably, a vacuum solenoid valve is provided between the vacuum pump and the flushing container, and a pressure reducing valve is provided between the air compressor and the flushing container.

[0013] Preferably, the test device further comprises a computer control system, which comprises a power supply system, a protection device and a PLC. The power supply system is electrically connected to each electrical component to control the start and stop of each electrical component.

[0014] Further preferably, the protection device can realize overload protection for the circuit of the entire test system. When the circuit system is overloaded or a circuit failure occurs, the power supply system of the corresponding circuit can be shut down in time to stop the circulation process.

[0015] Further preferably, the PLC controls the working state of each electrical component through an embedded program to achieve the setting of the duration, interval time, buffer time and number of cycles of the positive and negative pressure of the dynamic water flushing system.

[0016] In the testing device provided in the present application, by using heated alkaline dynamic water flushing, the test of the specimen under the coupling of three conditions of "strong alkaline water, temperature and load" is realized, which accurately corresponds to the actual operating conditions of the bridge deck and greatly improves the accuracy of the test results.

[0017] The present invention also provides an evaluation method based on the above-mentioned testing device, comprising the following steps:

[0018] S1. Form two groups of pavement structure specimens containing bonding layers, named control group d and test group s respectively;

[0019] S2. Use methyl-phenyl silicone material to seal specific areas of the test group S and perform freeze-thaw cycles on it;

[0020] S3. Place the test group s after freeze-thaw cycles into the flushing container, and adjust the position of the test piece by squeezing the positioning assembly to achieve water flushing of the bonding layer;

[0021] S4. Turn on the dynamic water flushing system and perform a dynamic water flushing test on the test group s;

[0022] S5. After the flushing is completed, the test group s is taken out, and the interlayer bonding strength τ of the control group d and the test group s is measured by a pulling device and a shearing device respectively. d拉 , τ d剪 , τ s拉 , τ s剪 ;

[0023] S6. Calculation of residual bond strength ratio γ of pavement structure specimens 拉 , γ 剪 , and select γ 拉 and γ 剪 The smaller value is taken as the final test result.

[0024] Furthermore, the bridge deck pavement structure described in step S1 should be the same as the actual engineering pavement structure, and the pavement structure test specimens include but are not limited to the combination of "steel bridge deck / asphalt layer", "concrete bridge deck / asphalt layer" or "asphalt layer / asphalt layer"; the test specimen is a cylindrical test specimen with a diameter of 100 mm, which is obtained by coring after forming by rotary compaction or wheel rolling: the rotary compaction method is applicable to the three pavement structures, and coring after forming by wheel rolling is applicable to the "concrete bridge deck / asphalt layer" and "asphalt layer / asphalt layer" structures. First form the lower structure, apply the adhesive layer material according to the actual amount, and then form the upper structure, so as to simulate the actual situation to the greatest extent and obtain more instructive test results.

[0025] Furthermore, when the pavement structure specimen described in step S1 is formed by the rotary compaction method, the number of compaction times is 65 times; when the wheel rolling method is used for forming, the number of compaction times is 8 round trips, and the total number of compaction times is 16 times. The void ratio of the pavement structure specimen after forming is 7.0%±1%. At this time, the void ratio of the pavement mixture is in a suitable range, which can make water flow more smoothly between layers and provide more stringent test conditions.

[0026] Furthermore, the specific area of ​​the pavement structure described in step S2 refers to all areas 10 mm above and below the joint between the structural layers, so as to examine the interlayer water damage resistance.

[0027] Furthermore, the sealing material is methyl-phenyl silicone material, the anti-seepage pressure is ≥1.0MPa, and the amount is not less than 500ml / m 2 , can completely seal the pores on the specimen surface; the freeze-thaw cycle test method is consistent with T0729-2000 in JTG E20.

[0028] The freeze-thaw cycle test is a typical water damage resistance test in the existing concrete evaluation system. Adding this test as step S3 in the present invention not only ensures that the method of the present invention does not deviate from the existing technical system, but also increases the severity of the method, which is conducive to obtaining more objective test conclusions.

[0029] Furthermore, in the dynamic water flushing pressure test described in step S4, the flushing pressure range is set to -0.075MPa to 0.12MPa, the dynamic water temperature is 60°C, the dynamic water pH is 12 to 14, and the number of flushing cycles is set to 1000 to 5000 times, wherein a positive value of the flushing pressure value indicates flushing from the first flushing port to the second flushing port, and a negative value of the flushing pressure value indicates flushing from the second flushing port to the first flushing port.

[0030] According to relevant research, the dynamic water pressure generated by a moving vehicle is an alternating positive and negative mode. When the vehicle speed is 100km / h, the dynamic water pressure ranges from about -0.076MPa to +0.115MPa. Based on this, the dynamic water pressure range of the present invention is designed, which can simulate the dynamic water pressure generated by the vehicle at a speed of about 100km / h, which corresponds to the load scenario when the bridge pavement structure layer is actually used; in addition, the study also found that the water between the pavement structure layers will dissolve various substances to form a strong alkaline aqueous solution, and the water flushes the interlayers with strong alkalinity, so the dynamic water solution is set to alkaline, and the dynamic water temperature is adjusted to 60°C at the same time, and the ability of the pavement layers to resist water damage under high temperature conditions is examined.

[0031] Furthermore, the interlayer bonding strength described in step S5 is obtained through a pull-out test, with direct pull-out strength and direct shear strength as evaluation indicators, and a test temperature of 60° C. is selected to represent high temperature conditions.

[0032] Furthermore, the residual bonding strength of the pavement structure specimen described in step S6 is γ 拉 , γ 剪 It refers to the residual bond strength ratio of the pavement structure of the test group and the control group, and the calculation formulas are:

[0033] γ 拉 =τ 拉s / τ 拉d Formula (I)

[0034] γ 剪 =τ 剪s / τ 剪d Formula (II)

[0035] In formula (I) and formula (II), γ 拉 is the residual tensile strength ratio of the specimen, dimensionless; γ 剪 It refers to the residual shear strength ratio of the specimen, dimensionless; τ 拉s It refers to the tensile strength of the test group s, in MPa; τ 拉d It refers to the tensile strength of the control group d, in MPa; τ 剪s It refers to the shear strength of the test group s, in MPa; τ 剪d It refers to the shear strength of the control group d, in MPa.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] For the bonding layer of the bridge deck pavement structure, a testing device and evaluation method for the interlayer water damage resistance of the bridge deck pavement structure layer are provided, which realizes the quantitative evaluation of the interlayer water damage resistance of the bridge deck pavement structure layer under the water-temperature-load coupling condition. More importantly, the testing device and evaluation method provided by the present invention can be used to accurately detect and evaluate the interlayer bonding condition of the bridge deck pavement structure layer, so as to objectively grasp the water damage resistance of the pavement layer, and then provide targeted guidance on the selection of bonding layer materials, pavement construction and maintenance, which can effectively prevent the occurrence or further development of interlayer bonding diseases of the pavement layer, and has significant significance for improving the service performance and service life of the bridge deck pavement structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 is a schematic diagram of the testing device provided in Example 1;

[0039] Among them, 10. transparent cylinder; 101. first flushing port; 102. second flushing port; 11. cover plate; 111. screw; 112. nut; 121. positioning plate; 122. push handle; 13. rack plate; 20. dynamic water storage tank; 21. air compressor; 211. pressure reducing valve; 22. vacuum pump; 221. vacuum solenoid valve; 23. pressure gauge; 31. heating device; 32. cooling device; 33. temperature control device; 40. test piece. DETAILED DESCRIPTION

[0040] The present invention will be further described below in conjunction with embodiments and drawings.

[0041] Example 1

[0042] A testing device for the water damage resistance between layers of a bridge deck pavement structure, such as Figure 1 As shown, including:

[0043] A flushing container, the flushing container comprises a transparent cylinder 10 and an extrusion positioning assembly therein, the left and right ends of the transparent cylinder 10 are open and provided with a cover plate 11, the cover plate 11 and the transparent cylinder 10 are fixed by a screw 111 and a nut 112, the upper and lower parts of the transparent cylinder 10 are respectively provided with a first flushing port 101 and a second flushing port 102, the transparent cylinder 10 is provided with an extrusion positioning assembly that can move in a horizontal direction, and in this embodiment, the transparent cylinder 10 is also provided with a shelf 13 for placing a test piece 40;

[0044] The dynamic water flushing system includes a dynamic water storage tank 20, an air compressor 21, a vacuum pump 22 and a pressure gauge 23. The dynamic water storage tank 20 is connected to the first flushing port 101 and the second flushing port 102 through the air compressor 21 and the vacuum pump 22 respectively. The pressure gauge 23 is arranged on the dynamic water storage tank 20;

[0045] The temperature control system includes a heating device 31, a cooling device 32 and a temperature control device 33. The heating device 31 and the cooling device 32 are respectively arranged in the dynamic water storage tank 20. The temperature control device 33 includes a temperature sensor and a temperature controller. The temperature sensor is arranged in the dynamic water storage tank 20. The temperature controller is electrically connected to the temperature sensor, the heating device 31 and the cooling device 32 respectively. The temperature controller is used to receive the temperature measured by the temperature sensor and control the heating device 31 and the cooling device 32 according to the measured temperature.

[0046] Preferably, the extrusion positioning assembly includes two symmetrically arranged positioning members, the positioning members include a positioning plate 121 and a push handle 122 , and the push handle 122 is located on a side of the positioning plate 121 away from the symmetry plane.

[0047] Preferably, a vacuum solenoid valve 221 is provided between the vacuum pump 22 and the flushing container, and a pressure reducing valve 211 is provided between the air compressor 21 and the flushing container.

[0048] Preferably, the test device further comprises a computer control system, which is not shown in the figure, and the computer control system comprises a power supply system, a protection device and a PLC. The power supply system is electrically connected to each electrical component to control the start and stop of each electrical component.

[0049] Further preferably, the protection device can realize overload protection for the circuit of the entire test system. When the circuit system is overloaded or a circuit failure occurs, the power supply system of the corresponding circuit can be shut down in time to stop the circulation process.

[0050] Further preferably, the PLC controls the working state of each electrical component through an embedded program to achieve the setting of the duration, interval time, buffer time and number of cycles of the positive and negative pressure of the dynamic water flushing system.

[0051] Example 2

[0052] The evaluation method using the test device provided in Example 1 comprises the following steps:

[0053] Step S1: Form two groups of pavement structure specimens, named as control group d and test group s respectively:

[0054] The interlayer structure under investigation is a "concrete bridge deck-asphalt layer" paving structure. The bonding layer materials are homemade modified emulsified asphalt (hereinafter referred to as A) and homemade modified emulsified asphalt (hereinafter referred to as B). The basic properties of A and B materials are shown in Tables 1 and 2.

[0055] Table 1 Basic properties of homemade adhesive material A

[0056]

[0057]

[0058] Table 2 Basic properties of homemade adhesive material B

[0059]

[0060] First, two lower concrete panels are formed, with a size of 300mm*300mm*50mm. After curing, the surface is shot blasted to expose the fresh surface;

[0061] Then, follow the 0.5km / m 2 Sprinkle A and B adhesive materials on two concrete panels respectively and wait for them to stabilize;

[0062] Secondly, the AC-13 asphalt mixture layer was formed on the concrete panel by wheel rolling method, with the size of 300mm*300mm*50mm, and the number of rolling times was 8 back and forth;

[0063] Finally, samples were taken from two composite rutting plates using a 100 mm diameter core drill and grouped into test groups A and B. s , B s , control group A d , B d .

[0064] Step S2: Use methyl-phenyl silicone material to seal the specific area of ​​the test group s, and perform one freeze-thaw cycle:

[0065] A s Group B s Take the concrete panel-asphalt layer joint as the center, stick a circle of transparent tape 10mm on both sides, and then press 600ml / m 2 The dosage of A s Group B s The test pieces were coated with methyl-phenyl silicone material; after the silicone material was completely cured, the transparent tape was removed and one freeze-thaw cycle was carried out according to the test method specified in T0729 of JTG E20-2011.

[0066] The methyl-phenyl silicone material was purchased from Nanjing Xingyou Transportation Technology Co., Ltd., and those skilled in the art may also use other commonly used commercially available materials whose impermeability pressure meets the requirements.

[0067] Step S3: Place the test group s after the freeze-thaw cycle into the flushing container, and adjust the position of the test piece by squeezing the positioning component to achieve water flushing of the bonding layer.

[0068] After freeze-thaw cycles, A s Group B s The side wall of the test piece is coated with water-based grease, and the test piece is placed in the flushing container of the test device of the present invention. The extrusion positioning components on the left and right cover plates are adjusted so that the joint of the concrete panel / asphalt layer test piece is exactly in the water flow flushing position.

[0069] Step S4: Turn on the dynamic water flushing system and perform a dynamic water flushing test on the test group s:

[0070] A dynamic water flushing process was set in the computer control system as follows: 0.12MPa flushing for 3s, -0.075MPa flushing for 3s, dynamic water temperature of 60°C, dynamic water pH of 13, and the dynamic water flushing process was cycled 3000 times in total.

[0071] After the settings are completed, the temperature control system will work first to heat the flushing water until its temperature reaches 60°C; after the water temperature is reached, the dynamic water flushing test can begin.

[0072] Step S5: Close the test device, take out the pavement structure specimens after the test, and use the pulling device and the shearing device to test the interlayer bonding strength τ of the pavement structure specimens of the control group and the test group respectively. d拉 , τ d剪 , τ s拉 , τ s剪 :

[0073] The pull-out test and shear test are completed using the UTM-30 multifunctional testing machine with special fixtures.

[0074] After the dynamic water flushing, s Group B s The specimens of group A were taken out and compared with those of control group A. d , B d They were placed in a 60°C environmental box for more than 3 hours, and interlaminar pull-off and interlaminar shear tests were performed at 60°C.

[0075] Step S6: Calculate the residual bonding strength ratio γ of the pavement structure specimen 拉 , γ 剪 .

[0076] The test results are shown in Table 3.

[0077] Table 3 Interlaminar pull-out and interlaminar shear test results

[0078]

[0079] The residual tensile strength ratio of the "concrete bridge deck-asphalt layer" pavement structure specimens prepared with two adhesive layer materials A and B after interlayer alkaline dynamic water scouring is γ 拉 , residual shear strength ratio γ 剪 As shown in Table 1. For material A, its 60℃ residual tensile strength ratio is γ 拉 =0.57, residual shear strength ratio γ 剪 =0.63, and 0.57 is the final test result of interlayer water damage resistance; for material B, its 60℃ residual tensile strength ratio is γ 拉 =0.72, residual shear strength ratio γ 剪 =0.82, and 0.72 is the final test result of interlayer water damage resistance. The above test results show that after freeze-thaw cycles and alkaline dynamic water scouring, the interlayer water damage resistance of the pavement structure using material A is 0.57 of the initial state, and the interlayer water damage resistance of the pavement structure using material B is 0.72 of the initial state. Therefore, the interlayer water damage resistance of bonding material B is better than that of bonding material A, and bonding material B should be selected for this bridge deck pavement structure.

Claims

1. A method for evaluating the water damage resistance performance of interlayers of a bridge deck pavement structure, characterized in that: The steps include: S1. Form two groups of pavement structure specimens containing bonding layers, named control group d and test group s respectively; S2. Block specific areas of the test group S and subject them to freeze-thaw cycles; S3. Place the test group s after freeze-thaw cycles into the flushing container, and adjust the position of the test piece by squeezing the positioning assembly to achieve water flushing of the bonding layer; S4. Turn on the dynamic water flushing system and perform a dynamic water flushing test on the test group s; S5. After the flushing is completed, the test group s is taken out and the interlayer bonding strength of the control group d and the test group s is measured using a pulling device. , , , ; S6. Calculation of residual bond strength ratio of pavement structure specimens , , and select and The smaller value is taken as the final test result; The interlayer bonding strength described in step S5 is obtained by a pull-out test and a shear test, with direct pull-out strength and direct shear strength as evaluation indicators, and the test temperature is 60° C.; The residual bonding strength ratio of the pavement structure specimen described in step S6 is , It refers to the residual bond strength ratio of the pavement structure of the test group and the control group, and the calculation formulas are: Formula (I) Formula (II) In formula (I) and formula (II), is the residual tensile strength ratio of the specimen, dimensionless; It refers to the residual shear strength ratio of the specimen, dimensionless; It refers to the tensile strength of test group s, in MPa; It refers to the pull-out strength of the control group d, in MPa; It refers to the shear strength of the test group s, in MPa; It refers to the shear strength of the control group d, in MPa.

2. The evaluation method according to claim 1, wherein: In step S1, the pavement structure specimen includes a combination of "steel bridge deck / asphalt layer", "concrete bridge deck / asphalt layer", and "asphalt layer / asphalt layer"; the specimen is a cylindrical specimen with a diameter of 100 mm, which is formed by rotary compaction or wheel rolling and then coring.

3. The evaluation method according to claim 2, characterized in that: When the rotary compaction method is used for molding, the compaction times are 65 times, and when the wheel rolling method is used for molding, the compaction times are 8 round trips, totaling 16 times.

4. The evaluation method according to claim 3, characterized in that: The void ratio of the paved structure specimen after forming is 7.0%±1%.

5. The evaluation method according to claim 1, wherein: In step S2, the test piece is sealed with a methyl-phenyl silicone material, the impermeability pressure of the methyl-phenyl silicone material is ≥1.0 MPa, and the amount used is not less than 500 ml / m 2 ; The specific area refers to all areas outside the 10mm above and below the adhesive layer.

6. The evaluation method according to claim 1, wherein: In step S4, the flushing pressure range is set to -0.075MPa to 0.12MPa, the moving water temperature is 60°C, the moving water pH is 12~14, and the number of flushing cycles is set to 1000~5000 times, wherein a positive value of the flushing pressure value indicates flushing from the first flushing port to the second flushing port, and a negative value of the flushing pressure value indicates flushing from the second flushing port to the first flushing port.

7. A testing device for implementing the evaluation method according to any one of claims 1 to 6, characterized in that: include: A flushing container, comprising a transparent cylinder and an extrusion positioning assembly inside the transparent cylinder that can move in a horizontal direction, the left and right ends of the transparent cylinder are open and provided with a cover plate, and a first flushing port and a second flushing port are respectively opened on the top and bottom of the transparent cylinder; The dynamic water flushing system comprises a dynamic water storage tank, an air compressor, a vacuum pump and a pressure gauge. The dynamic water storage tank is connected to the first flushing port and the second flushing port through the air compressor and the vacuum pump respectively. The pressure gauge is arranged on the dynamic water storage tank. A temperature control system includes a heating device, a cooling device and a temperature control device. The heating device and the cooling device are respectively arranged in a dynamic water storage tank. The temperature control device includes a temperature sensor and a temperature controller. The temperature sensor is arranged in the dynamic water storage tank. The temperature controller is respectively electrically connected to the temperature sensor, the heating device and the cooling device. The temperature controller is used to receive the temperature measured by the temperature sensor and control the heating device and the cooling device according to the measured temperature.

8. The testing device according to claim 7, characterized in that: The extrusion positioning assembly comprises two symmetrically arranged positioning members, the positioning members comprise a positioning plate and a push handle, and the push handle is located on a side of the positioning plate away from the symmetry plane.

9. The testing device according to claim 7, characterized in that: A vacuum solenoid valve is arranged between the vacuum pump and the flushing container, and a pressure reducing valve is arranged between the air compressor and the flushing container.

10. The testing device according to claim 7, characterized in that: The test device also includes a computer control system, which includes a power supply system, a protection device and a PLC; the computer control system is electrically connected to each electrical component, and the power supply system controls the start and stop of each electrical component; the protection device realizes circuit overload protection; the PLC regulates the working state of each electrical component through an embedded program, and realizes the setting of the duration, interval time, buffer time and number of cycles of the positive and negative pressure of the dynamic water flushing system.

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