An asphalt pavement interlayer waterproof bonding layer pressure water permeation test device and method

Abstract

The application discloses a kind of asphalt pavement interlayer waterproof adhesive layer pressure water permeation test device and method, including bearing base, clamping sealing assembly, separate pressurized water cavity, pressure system, water collection weighing system and data acquisition display unit, clamping sealing assembly includes lower pressing plate, upper pressing plate, outer fixed screw rod, fixed nut, inner side connection adjusting screw rod, adjusting nut and upper pressing plate perimeter sealing strip;Separate pressurized water cavity is independently arranged outside clamping sealing assembly, test liquid in it is transported to water cavity mounting seat by pressurized water cavity water delivery pipe, and is guided into the compressed area above test piece by water cavity mounting seat;Lower pressing plate is equipped with square drain hole, effusion is collected by water collecting tank and is weighed continuously by electronic balance.The application adopts separate pressurized water supply structure, is convenient for water injection, disassembly and maintenance, can reduce the influence of water cavity to pressing plate clamping structure, improves the sealing reliability of test, operation convenience and data continuity.

Description

Technical Field

[0001] This invention relates to the field of road engineering material performance testing technology, and in particular to a pressure seepage test device and method for an interlayer waterproof bonding layer of asphalt pavement using a separate pressurized water chamber. Background Technology

[0002] In asphalt pavements and other road structures containing waterproof bonding layers, the waterproof bonding layer serves both as an interlayer bond and as a means of water blocking, seepage prevention, and delaying water damage. During actual service, rainwater or snowmelt can penetrate the surface layer and interface areas under traffic loads, temperature changes, and structural micro-cracks. When the waterproof bonding layer's impermeability is insufficient, problems such as interlayer delamination, interface peeling, potholes, loosening, and water damage to the base layer can easily occur. Wheel loads also create dynamic water pressure within and between asphalt pavements. Therefore, it is necessary to evaluate the interlayer waterproofing performance of asphalt pavements under pressurized water conditions, especially the water-blocking capacity of the waterproof bonding layer under direct pressurized water.

[0003] Existing water permeability tests mostly evaluate surface water permeability or the permeability of a single material, making it difficult to reflect the water-blocking effect of the interlayer waterproofing bonding layer in asphalt pavement. If a composite specimen containing an asphalt mixture surface layer is used, the pore structure and permeability differences of the surface layer itself will affect the process by which the test liquid reaches the interlayer; at the same time, if the perimeter of the specimen is not reliably sealed, the test liquid may also form bypass leakage along the sidewalls, resulting in test results that cannot truly reflect the interlayer waterproofing performance of asphalt pavement.

[0004] Some pressure seepage devices install the pressurized water chamber directly on the upper pressure plate. The water filling, venting, disassembly and cleaning of the water chamber must be completed above the clamping structure. This not only occupies operating space, but also the weight of the water chamber, the connection load and the disassembly process can easily affect the stress state of the upper pressure plate and the stability of the specimen clamping. When multiple sets of specimens need to be tested continuously, the overall disassembly efficiency is low.

[0005] In addition, existing devices have shortcomings such as unstable pressure regulation, inconvenient pipe joint disassembly and cleaning, insufficient collection of exudate, and difficulty in recording pressure data and seepage quality data synchronously. Manual timed readings are difficult to accurately capture the initial seepage time and the process of trace seepage. After the test, only the collected water volume is usually counted, and the amount of water absorbed inside the specimen is not weighed, which makes it difficult to fully reflect the distribution of pressurized water in the specimen.

[0006] Based on the above-mentioned technical problems, the present invention provides a device and method for testing the pressure seepage of the interlayer waterproof bonding layer of asphalt pavement by separating the pressurized water chamber from the pressure plate clamping structure and delivering pressurized liquid to the specimen through the pressurized water chamber water supply pipe and the water chamber mounting seat. Summary of the Invention

[0007] The purpose of this invention is to provide a pressure seepage test device and method for the interlayer waterproof bonding layer of asphalt pavement, which allows pressurized water to act directly on the waterproof bonding layer coated on the cement concrete slab, and evaluates the interlayer waterproof performance of asphalt pavement by the collected water quality and the water absorption quality of the specimen, while improving the clamping stability, sealing reliability, disassembly and cleaning convenience of the device, as well as the continuity of pressure and seepage data acquisition.

[0008] To achieve the above objectives, the present invention provides the following solution: The present invention provides a pressure seepage test device for the interlayer waterproof bonding layer of asphalt pavement, comprising: A support base, located at the bottom of the device, is used to support the upper clamping structure and reserve installation space for the water collection tank and electronic balance; A clamping and sealing assembly includes a lower pressure plate, an upper pressure plate, an outer fixing screw, a fixing nut, an inner connecting adjusting screw, an adjusting nut, and a sealing strip around the upper pressure plate. A specimen installation space is formed between the upper and lower pressure plates. This space is used to install a specimen consisting of a cement concrete slab and a waterproof adhesive layer applied to its surface, with the cement concrete slab serving as the pressure-bearing layer. The outer fixing screw and fixing nut are used for overall fixation, while the inner connecting adjusting screw and adjusting nut are used to adjust the spacing between the pressure plates and the clamping force on the specimen. The sealing strip around the upper pressure plate seals the periphery of the upper surface of the waterproof adhesive layer. A separate pressurized water chamber is provided outside the clamping and sealing assembly and is separated from the upper pressure plate. The test liquid in the separate pressurized water chamber is transported to the water chamber mounting seat through the pressurized water chamber water supply pipe. The water chamber mounting seat is installed on the upper pressure plate and guides the test liquid above the specimen. The test liquid directly acts on the upper surface of the waterproof adhesive layer. A pressure system, which is connected to a separate pressurized water chamber, is used to generate, regulate, display and monitor test pressure, and to provide safe pressure relief in case of overpressure. A water collection and weighing system, comprising a water collection tank and an electronic balance, wherein the water collection tank is located below the square drain hole of the lower pressure plate and placed on the electronic balance, and the water collection and weighing system is used to collect and continuously weigh the water that seeps out from the bottom of the specimen. The data acquisition and display unit receives pressure signals and mass signals output by the electronic balance, respectively, and is used to synchronously display, store and process test data.

[0009] According to the pressure seepage test device for interlayer waterproof bonding layer of asphalt pavement provided by the present invention, the separate pressurized water chamber is provided with a pressurized water inlet and a detachable and washable joint. The pressurized water inlet is used to add test liquid, and the detachable and washable joint is used to connect the pressure pipeline and the pressurized water chamber water supply pipe, so as to facilitate the disassembly, flushing and maintenance of the water chamber and pipeline.

[0010] According to the pressure seepage test device for interlayer waterproof bonding layer of asphalt pavement provided by the present invention, one end of the pressurized water chamber water supply pipe is detachably connected to the liquid outlet end of the separate pressurized water chamber, and the other end is detachably connected to the water chamber mounting seat; the water chamber mounting seat is fixed on the upper pressure plate, and its internal flow channel is connected to the upper part of the specimen installation space.

[0011] According to the pressure seepage test device for interlayer waterproof bonding layer of asphalt pavement provided by the present invention, a square drainage hole is opened in the middle of the lower pressure plate. The square drainage hole is set in accordance with the installation space of the specimen, so that the liquid seeping from the bottom of the specimen falls directly into the water collection tank, reducing the retention and weighing error caused by the intermediate guiding component.

[0012] According to the pressure seepage test device for interlayer waterproof bonding layer of asphalt pavement provided by the present invention, the pressure system includes an air compressor or high-pressure pump, a pressure pipeline, a pressure regulating valve, a mechanical pressure gauge, a safety relief valve, and a sensor interface; the pressure pipeline connects the pressure source to the separate pressurized water chamber, the pressure regulating valve is used to adjust the test pressure, the mechanical pressure gauge is used to display the pressure on site, the safety relief valve is used for overpressure protection, and the sensor interface is used to connect a pressure sensor.

[0013] According to the pressure seepage test device for interlayer waterproof bonding layer of asphalt pavement provided by the present invention, the mechanical pressure gauge and pressure sensor are used to detect the pressure of the same pressure system, and the signal output terminal of the pressure sensor is connected to the data acquisition and display unit to realize mutual verification between mechanical reading and electronic acquisition.

[0014] According to the pressure seepage test device for interlayer waterproof bonding layer of asphalt pavement provided by the present invention, the water collection tank is detachably placed on the weighing pan of the electronic balance, the opening of the water collection tank faces the square drainage hole, and gaps are left between the water collection tank and the bearing base and the lower pressure plate to avoid the external support force or friction force affecting the weighing result.

[0015] According to the pressure seepage test device for interlayer waterproof bonding layer of asphalt pavement provided by the present invention, the electronic balance has a data output terminal and is connected to a data acquisition and display unit through a data cable to continuously output seepage quality data.

[0016] According to the pressure seepage test device for interlayer waterproof bonding layer of asphalt pavement provided by the present invention, the data acquisition and display unit is a computer with data acquisition software, a data recorder, an embedded acquisition display or a programmable control terminal, which can record pressure, mass and time, and calculate the cumulative water volume, seepage rate and initial seepage time.

[0017] A method for pressure seepage test of interlayer waterproof bonding layer in asphalt pavement includes the following steps: Step 1, Test preparation and instrument zeroing: Check the integrity of the separate pressurized water chamber, pressurized water chamber water supply pipe, water chamber mounting base, detachable and washable joint, upper pressure plate perimeter sealing strip and pressure system, put the system in a depressurized state, and complete the zeroing and calibration of the electronic balance and data acquisition and display unit. Step 2: Prepare and install the specimen and seal the edges: Apply the specified amount of asphalt pavement interlayer waterproof bonding material evenly to the upper surface of the cement concrete slab, and cure it to the specified state to form a specimen. The cement concrete slab serves as the bearing layer. Place the specimen in the specimen installation space between the upper and lower pressure plates with the waterproof bonding layer facing upwards. Seal the sides of the specimen. Adjust the clamping force by connecting the inner adjusting screw and adjusting nut to make the sealing strip around the upper pressure plate press against the periphery of the upper surface of the specimen. Then fix the specimen by fixing the outer fixing screw and fixing nut. Step 3, install the pressurized water chamber and inject the test liquid: arrange the separate pressurized water chamber on the outside of the clamping structure, connect it to the water chamber mounting base through the pressurized water chamber water supply pipe, add the test liquid through the pressurized water injection port and remove the gas in the pipeline; Step 4, low-pressure leak detection, programmed pressurization and data acquisition: First, check the sealing of the water cavity, pipeline, joint and the area around the test specimen with low pressure. After confirming that there is no leakage, pressurize or maintain pressure according to the preset program. Based on the test assumption that the asphalt pavement surface layer is permeable, the test liquid is applied directly to the surface of the waterproof bonding layer. Pressure data and water quality data collected in the water collection tank are collected simultaneously during the test. Step 5: Depressurization, Disassembly, Specimen Drying, and Evaluation: After the test, completely depressurize, disassemble the specimen and pressurized connection components, remove free water from the specimen surface and weigh the wet mass, dry the specimen at a specified temperature for a specified time, and weigh the dry mass after cooling. The difference between the wet mass and the dry mass is used to determine the water absorption mass of the specimen. Record the mass of water collected in the water collection tank, clean the separate pressurized water chamber, pressurized water chamber water supply pipe, detachable and washable joint, water chamber mounting base, and water collection tank, and evaluate the interlayer waterproofing performance of the asphalt pavement based on the pressure data, the mass of collected water, and the water absorption mass of the specimen.

[0018] The present invention discloses the following technical effects: This invention arranges the separate pressurized water chamber independently on the outside of the clamping and sealing assembly. The pressurized test liquid is delivered to the upper surface of the specimen through the pressurized water chamber water supply pipe and the water chamber mounting seat. This avoids the pressurized water chamber being directly installed on the upper pressure plate, which would occupy operating space or affect the force on the pressure plate. This makes specimen installation, clamping adjustment and switching between multiple test groups more convenient.

[0019] This invention employs a structure in which an outer fixing screw and an inner connecting adjusting screw work together, which ensures the overall stability of the device connection and allows for fine adjustment of the clamping force on the specimen. The sealing strip around the upper pressure plate, in conjunction with the specimen sealing edge, effectively blocks peripheral bypass leakage, and the square drainage hole allows the exudate to directly enter the water collection tank, improving the accuracy of the seepage measurement.

[0020] This invention improves the cleaning and maintenance efficiency of water chambers and pipelines through detachable and washable joints, and synchronously connects pressure sensors and electronic balances to the data acquisition and display unit, which can continuously record pressure, cumulative water volume and seepage rate, accurately capture the initial seepage time and trace seepage process; after the test, the water absorption mass of the specimen is obtained by the difference between the wet mass and the dry mass after drying, and combined with the water mass collected in the water collection tank, the interlayer waterproofing performance of asphalt pavement can be evaluated more completely, improving the continuity, traceability and evaluation accuracy of test data. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments are briefly described below. Obviously, the following drawings are only some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the overall structure of the pressure seepage test device for the interlayer waterproof bonding layer of asphalt pavement according to the present invention; Figure 2 This is a schematic diagram of the structure of the separate pressurized water chamber of the present invention; Figure 3 This is a schematic diagram of the upper and lower pressure plates of the present invention; Figure 4 This is a schematic diagram of the connection structure of the pressure system of the present invention; Figure 5 This is a schematic flowchart of the pressure seepage test method for the interlayer waterproof bonding layer of asphalt pavement according to the present invention.

[0023] The component names corresponding to each number in the above figures are as follows: 1. Support base; 2. Lower pressure plate; 4. Upper pressure plate; 5. Separate pressurized water chamber; 6. Pressurized water chamber water supply pipe; 7. Water chamber mounting seat; 8. External fixing screw; 9. Fixing nut; 10. Air compressor or high-pressure pump; 11. Pressure pipeline; 12. Pressure regulating valve; 13. Mechanical pressure gauge; 14. Safety pressure relief valve; 15. Sensor interface; 16. Upper pressure plate perimeter sealing strip; 17. Water collection tank; 18. Inner connecting adjusting screw; 19. Adjusting nut; 20. Electronic balance; 21. Data acquisition and display unit; 24. Square drain hole; 25. Detachable and washable connector; 27. Pressurized water inlet; 29. ​​Specimen installation space. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are all within the scope of protection of the present invention.

[0025] To make the objectives, features, and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] Reference Figures 1-4 The present invention provides a pressure seepage test device for interlayer waterproof bonding layer of asphalt pavement, including a bearing base 1, a lower pressure plate 2, an upper pressure plate 4, a separate pressurized water chamber 5, a pressurized water chamber water supply pipe 6, a water chamber mounting seat 7, a pressure system, a water collection and weighing system, and a data acquisition and display unit 21.

[0027] The support base 1 is located at the bottom of the device and is used to support the lower pressure plate 2, the upper pressure plate 4 and their connecting components. The interior or lower part of the support base 1 forms an open space for placing the water collection tank 17 and the electronic balance 20, and facilitates the operator to observe, pick up and clean the water collection components.

[0028] The lower pressure plate 2 is positioned above the bearing base 1, and the upper pressure plate 4 is positioned parallel to the lower pressure plate 2 above it, forming a specimen installation space 29 between the upper pressure plate 4 and the lower pressure plate 2. Several outer fixing screws 8 are arranged around the outer periphery of the pressure plates and cooperate with fixing nuts 9 to fix the overall position of the bearing base 1, the lower pressure plate 2, and the upper pressure plate 4; several inner connecting adjusting screws 18 are arranged around the periphery of the specimen installation space 29 and cooperate with adjusting nuts 19 to adjust the distance and clamping force between the upper pressure plate 4 and the lower pressure plate 2. The specimen used in the test consists of a cement concrete slab and a waterproof adhesive layer applied to its upper surface, with the cement concrete slab placed below as the bearing layer and the waterproof adhesive layer facing upwards.

[0029] The separate pressurized water chamber 5 is separate from the upper pressure plate 4 and is arranged on the outside of the clamping structure. The separate pressurized water chamber 5 can be made of pressure-resistant metal, transparent pressure-resistant material or a combination thereof, and its volume is determined according to the specimen size, test pressure and test duration to store the liquid required for the test and form a stable pressurized liquid supply.

[0030] A liquid outlet is provided at the lower or side of the separate pressurized water chamber 5, and the outlet is connected to the pressurized water chamber supply pipe 6 via a detachable and washable connector 25. The other end of the pressurized water chamber supply pipe 6 is connected to the water chamber mounting seat 7 set on the upper pressure plate 4. The test liquid in the separate pressurized water chamber 5 is transported to the water chamber mounting seat 7 through the pressurized water chamber supply pipe 6, and then directly acts on the upper surface of the waterproof bonding layer through the internal flow channel of the water chamber mounting seat 7. Based on the test assumption that the asphalt pavement surface layer is permeable, the specimen does not have an asphalt mixture upper layer to reduce the influence of the surface layer's own water permeability difference on the evaluation of interlayer waterproofing performance.

[0031] A square drainage hole 24 is provided in the middle of the lower pressure plate 2, and the square drainage hole 24 corresponds vertically to the specimen installation space 29 and the pressure area of ​​the specimen. The water collection tank 17 is placed directly below the square drainage hole 24 with its opening facing upwards, and the electronic balance 20 is located below the water collection tank 17, so that the exudate falls directly into the water collection tank 17 under the action of gravity and is continuously weighed.

[0032] The data acquisition and display unit 21 is connected to the pressure sensor and the electronic balance 20 respectively, and is used to synchronously acquire test pressure and collected water quality data, and record time information according to the preset sampling interval; based on the acquired data, the cumulative collected water volume, the collected water volume per unit time, the seepage rate and the initial seepage time can be calculated.

[0033] Furthermore, referring to Figure 2 The separate pressurized water chamber 5 is equipped with a pressurized water inlet 27. Before the test, clean water, tracer liquid or other specified test liquid can be added into the chamber through the pressurized water inlet 27; after the liquid injection is completed and the gas in the chamber and pipeline is removed, the pressurized water inlet 27 is sealed to ensure the airtightness of the chamber during the pressurization process.

[0034] A detachable and washable connector 25 can be installed at the connection points between the separate pressurized water chamber 5 and the pressure pipeline 11, as well as the pressurized water chamber supply pipe 6. The detachable and washable connector 25 can be a threaded connector, quick-connect connector, or flange connector, allowing for quick disassembly after the test to flush the inside of the water chamber, pipeline, and connectors, reducing the impact of residual liquid and impurities on subsequent tests. A mechanical pressure gauge 13 and a safety relief valve 14 can be installed on the upper part of the separate pressurized water chamber 5 or on the pipeline connected to it.

[0035] Furthermore, the water chamber mounting base 7 is fixed on the upper pressure plate 4. The inlet end of the water chamber mounting base 7 is sealed to the pressurized water chamber water supply pipe 6, and the outlet end is connected to the liquid passage hole on the upper pressure plate 4. The water chamber mounting base 7 can be installed by threads, flanges or fasteners so that the upper pressure plate 4 and the test piece can be assembled and disassembled without disassembling the separate pressurized water chamber 5.

[0036] During pressurization, the pressurized liquid enters the pressurized water chamber supply pipe 6 from the separate pressurized water chamber 5 and is evenly introduced above the specimen through the water chamber mounting seat 7. Since the separate pressurized water chamber 5 does not directly bear the load of the upper pressure plate 4, the liquid injection volume of the water chamber and the connection status of the pressure pipeline will not significantly change the vertical clamping load of the pressure plate, which is beneficial to maintaining the stability of the specimen's stress and sealing status.

[0037] A perimeter sealing strip 16 is provided around the pressure area on the lower surface of the upper pressure plate 4. When installing the test specimen, the sides of the test specimen can be sealed with sealing material first, and then the upper pressure plate 4 can be pressed down by the inner connecting adjusting screw 18 and adjusting nut 19. The perimeter sealing strip 16 of the upper pressure plate will undergo elastic deformation and fit against the periphery of the upper surface of the test specimen. Then, the overall structure is locked by the outer fixing screw 8 and fixing nut 9, thereby limiting the bypass leakage of pressurized liquid along the periphery of the test specimen.

[0038] An air compressor or high-pressure pump 10 serves as a pressure source, applying air or hydraulic pressure to the separate pressurized water chamber 5 via a pressure pipeline 11. A pressure regulating valve 12 is connected in series on the pressure pipeline 11, controlling the pressure entering the separate pressurized water chamber 5 by adjusting the valve opening, so that the test pressure can be increased step by step according to the set value, maintained at a constant pressure, or changed according to a program.

[0039] Mechanical pressure gauge 13 is connected to separate pressurized water chamber 5 or pressure pipeline 11 for on-site display of actual pressure; safety relief valve 14 is connected to the pressurized system and automatically opens to relieve pressure when the system pressure exceeds a preset threshold to prevent overpressure damage to water chamber, pipeline and connectors; sensor interface 15 is used to install pressure sensor.

[0040] The pressure sensor detects the real-time pressure of the pressurized system through the sensor interface 15 and transmits the pressure signal to the data acquisition and display unit 21. The mechanical pressure gauge 13 and the pressure sensor can independently detect the same pressure. The operator can use the mechanical reading to verify the electronically acquired value and promptly determine the system status in case of pressure adjustment or abnormal conditions.

[0041] Furthermore, the rated pressure resistance of the pressure pipeline 11, the separate pressurized water chamber 5, the pressurized water chamber water supply pipe 6, and the water chamber mounting base 7 are all higher than the maximum test pressure; each connection is sealed with a gasket, sealing ring, or threaded sealing material, and the operating pressure of the safety relief valve 14 is not higher than the system's allowable safety pressure.

[0042] The electronic balance 20 is placed on the bottom platform of the support base 1, and the water collection tank 17 is placed directly on the weighing pan of the electronic balance 20. The opening size of the water collection tank 17 covers the water outlet range of the square drain hole 24, and the internal volume is greater than the maximum expected seepage volume of the test to prevent liquid from overflowing during the test.

[0043] Furthermore, the water collection tank 17 is completely detachable, and can be directly removed from the electronic balance 20 for emptying and cleaning after the test. A gap is left between the water collection tank 17 and the lower pressure plate 2, the support base 1, and other fixed components to prevent the water collection tank 17 from being subjected to additional support or friction that could affect the weighing of the electronic balance 20.

[0044] The electronic balance 20 is equipped with a data output terminal, which is connected to the data acquisition and display unit 21 via a data cable to continuously output the real-time mass change of the water collection tank 17 and the liquid inside it. Before the test, the electronic balance 20 is zeroed, and the mass increment can be directly converted into the cumulative collected water mass; given the known density of the test liquid, it can also be converted into the cumulative collected water volume. After the test, the electronic balance 20 can also be used to weigh the wet mass and the dry mass of the specimen to determine the water absorption mass of the specimen.

[0045] Furthermore, electronic balances 20 with different ranges and resolutions can be selected according to the experimental accuracy requirements, and filtering, tare, sampling period and outlier judgment parameters can be set in the acquisition software to reduce the impact of vibration, airflow and instantaneous dripping on the data curve.

[0046] The data acquisition and display unit 21 can be a computer with data acquisition software, a data logger, an embedded acquisition display or a programmable control terminal, and can be equipped with a pressure signal input port, a quality signal input port, a display screen and operation buttons.

[0047] The data acquisition and display unit 21 is used to set parameters such as specimen number, test pressure, pressure holding time, and sampling interval, and displays the pressure, cumulative water accumulation, and seepage rate in real time, while saving pressure data, mass data, and timestamps. After the test, the interlayer waterproofing performance of asphalt pavement can be evaluated by combining the initial seepage time, the water accumulation at the specified time, the seepage rate under the specified pressure, and the water absorption mass of the specimen.

[0048] refer to Figure 5 The method for pressure seepage test of interlayer waterproof bonding layer of asphalt pavement of the present invention includes the following steps: Step 1: Test preparation and instrument zeroing. Check the condition of the separate pressurized water chamber 5, pressurized water chamber supply pipe 6, water chamber mounting base 7, pressure pipeline 11, detachable and washable connector 25, upper pressure plate perimeter sealing strip 16, and safety pressure relief valve 14 to confirm that there is no residual pressure in the system; place the water collection tank 17 on the electronic balance 20, zero the electronic balance 20 and data acquisition and display unit 21, and complete the pressure sensor calibration.

[0049] Step 2: Prepare and install the specimen and seal the edges. Select a cement concrete slab with dimensions suitable for the specimen installation space 29, clean and dry its upper surface, and apply the specified amount of asphalt pavement interlayer waterproof bonding material evenly. After curing to the specified state, the specimen is formed; the cement concrete slab serves as the bearing layer, with the waterproof bonding layer facing upwards. Place the specimen in the specimen installation space 29 between the upper pressure plate 4 and the lower pressure plate 2, so that the pressurized water directly acts on the upper surface of the waterproof bonding layer; seal the edges of the specimen, tighten the adjusting nut 19 to adjust the clamping state of the inner connecting adjusting screw 18, so that the sealing strip 16 around the upper pressure plate evenly presses the specimen, and then tighten the fixing nut 9 to lock the outer fixing screw 8.

[0050] Step 3: Install the pressurized water chamber and inject the test liquid. Place the separate pressurized water chamber 5 on the outside of the clamping structure, and connect the pressurized water chamber supply pipe 6 to the separate pressurized water chamber 5 and the water chamber mounting base 7 respectively through the detachable washable connector 25; open the pressurized water inlet 27 and add the specified volume of test liquid, so that the liquid fills the flow channels of the separate pressurized water chamber 5, the pressurized water chamber supply pipe 6 and the water chamber mounting base 7, and seal the pressurized water inlet 27 after removing the gas.

[0051] Step 4: Low-pressure leak detection and pressurization according to the procedure, while simultaneously collecting pressure and collected water data. Start the air compressor or high-pressure pump 10, apply a lower pressure through the pressure regulating valve 12, and check for leaks in the separate pressurized water chamber 5, pressure pipeline 11, pressurized water chamber water supply pipe 6, water chamber mounting base 7, and the area around the specimen; after confirming that the seal is normal, pressurize or maintain pressure according to the specified pressure procedure. Based on the test assumption that the asphalt pavement surface layer is permeable, the test liquid acts directly on the upper surface of the waterproof adhesive layer. The data acquisition and display unit 21 simultaneously records the output of the pressure sensor and electronic balance 20. The liquid seeping from the bottom of the specimen falls into the water collection tank 17 through the square drainage hole 24.

[0052] Step 5: After depressurization, disassemble the specimen and device, weigh and dry the specimen, clean the device, and evaluate the test results. After the test, turn off the pressure source, slowly adjust the pressure regulating valve 12 or open the safety pressure relief valve 14 to release the pressure. After the mechanical pressure gauge 13 and pressure sensor both show no pressure, disassemble the pressurized water chamber water supply pipe 6, the upper pressure plate 4, and the specimen; take out the water collection tank 17 and record the mass of the collected water, remove the free water on the surface of the specimen, and weigh the wet mass of the specimen using an electronic balance 20; dry the specimen at the specified temperature for the specified time, take it out, cool it to room temperature, and weigh the dry mass. The difference between the wet mass and the dry mass is taken as the water absorption mass of the specimen; then clean the water collection tank 17, the separate pressurized water chamber 5, the water chamber mounting base 7, and the detachable and washable joint 25, and evaluate the interlayer waterproofing performance of the asphalt pavement based on the pressure curve, the mass of the collected water, the water absorption mass of the specimen, the seepage rate, and the initial seepage time.

[0053] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings and are used only to facilitate the description of this invention, and are not intended to indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0054] The embodiments described above are merely illustrative of preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Various equivalent substitutions, modifications, and improvements made by those skilled in the art without departing from the spirit and technical solutions defined in the claims should fall within the scope of protection of the present invention.

Claims

1. A pressure seepage test device for interlayer waterproof bonding layer of asphalt pavement, characterized in that, include: The support base (1) is located at the bottom of the device and is used to support the clamping structure and reserve installation space for the water collection and weighing components. A clamping and sealing assembly is disposed above the bearing base (1) and includes a lower pressure plate (2), an upper pressure plate (4), several outer fixing screws (8), several fixing nuts (9), several inner connecting and adjusting screws (18), several adjusting nuts (19), and a sealing strip (16) around the upper pressure plate; the upper pressure plate (4) is disposed parallel above the lower pressure plate (2), and a specimen installation space (29) is formed between the upper pressure plate (4) and the lower pressure plate (2), the specimen installation space (29) being used for mounting. The specimen is made of a cement concrete slab and a waterproof adhesive layer applied to its surface, with the cement concrete slab serving as the bearing layer; the outer fixing screw (8) and fixing nut (9) are used to fix the relative positions of the upper pressure plate (4), the lower pressure plate (2) and the bearing base (1); the inner connecting adjusting screw (18) and adjusting nut (19) are used to adjust the distance between the upper pressure plate (4) and the lower pressure plate (2) and the clamping force on the specimen; the sealing strip (16) around the upper pressure plate is arranged around the pressure area of ​​the specimen. A separate pressurized water chamber (5) is provided on the outside of the clamping and sealing assembly; the liquid outlet of the separate pressurized water chamber (5) is connected to the pressurized water chamber water supply pipe (6), and the other end of the pressurized water chamber water supply pipe (6) is connected to the upper pressure plate (4) through the water chamber mounting seat (7). The internal flow channel of the water chamber mounting seat (7) is connected to the upper part of the specimen installation space (29). The pressure system includes an air compressor or high-pressure pump (10), a pressure line (11), a pressure regulating valve (12), a mechanical pressure gauge (13), a safety relief valve (14), and a sensor interface (15). The pressure system is used to apply and regulate the test pressure to the test liquid in the separate pressurized water chamber (5). A water collection and weighing system, comprising a water collection tank (17) and an electronic balance (20), wherein the water collection tank (17) is located below the lower pressure plate (2) and on the weighing pan of the electronic balance (20), and the water collection and weighing system is used to collect and weigh the liquid seeping out of the specimen; The data acquisition and display unit (21) is connected to the pressure system and the electronic balance (20) respectively, and is used to synchronously acquire, display and store pressure data, seepage quality data and corresponding time data.

2. The pressure seepage test device for interlayer waterproof bonding layer of asphalt pavement according to claim 1, characterized in that, The separate pressurized water chamber (5) is provided with a pressurized water inlet (27) and at least two detachable and washable connectors (25), one of which is used to connect to the pressurized water chamber water supply pipe (6), and the other is used to connect to the pressure pipeline (11); the mechanical pressure gauge (13) and the safety pressure relief valve (14) are provided in the separate pressurized water chamber (5) or on the pipeline connected to it.

3. The pressure seepage test device for the interlayer waterproof bonding layer of asphalt pavement according to claim 1, characterized in that, The water cavity mounting base (7) is fixed on the upper pressure plate (4). The water cavity mounting base (7) is provided with an inlet channel that is detachably connected to the pressurized water cavity water supply pipe (6) and an outlet channel facing the upper surface of the waterproof adhesive layer. The inlet channel and the outlet channel are interconnected.

4. The pressure seepage test device for the interlayer waterproof bonding layer of asphalt pavement according to claim 1, characterized in that, The outer fixing screw (8) is located on the outer periphery of the upper pressure plate (4) and the lower pressure plate (2), and the inner connecting adjusting screw (18) is located on the periphery of the specimen installation space (29). By screwing the fixing nut (9) and the adjusting nut (19), the sealing strip (16) around the upper pressure plate is pressed against the periphery of the upper surface of the waterproof adhesive layer, and together with the side sealing edge of the specimen, it blocks the bypass leakage.

5. The pressure seepage test device for interlayer waterproof bonding layer of asphalt pavement according to claim 1, characterized in that, The lower pressure plate (2) has a square drainage hole (24) in the middle. The square drainage hole (24) is arranged in correspondence with the specimen installation space (29), and the opening of the water collection tank (17) is located directly below the square drainage hole (24).

6. The pressure seepage test device for the interlayer waterproof bonding layer of asphalt pavement according to claim 1, characterized in that, The pressure pipeline (11) connects the air compressor or high-pressure pump (10) to the separate pressurized water chamber (5). The pressure regulating valve (12) is connected in series on the pressure pipeline (11). The mechanical pressure gauge (13), the safety relief valve (14), and the sensor interface (15) are respectively connected to the inner cavity of the pressure pipeline (11) or the separate pressurized water chamber (5).

7. The pressure seepage test device for interlayer waterproof bonding layer of asphalt pavement according to claim 6, characterized in that, The sensor interface (15) is used to connect to the pressure sensor, and the signal output terminal of the pressure sensor is connected to the data acquisition and display unit (21); the mechanical pressure gauge (13) is used to display the test pressure on site, and the safety relief valve (14) is used to release pressure when the pressure exceeds the preset threshold.

8. The pressure seepage test device for the interlayer waterproof bonding layer of asphalt pavement according to claim 1, characterized in that, The water collection tank (17) is movably placed on the weighing pan of the electronic balance (20). There is a gap between the water collection tank (17) and the lower pressure plate (2) and the supporting base (1). The volume of the water collection tank (17) is greater than the maximum expected seepage volume in a single test.

9. The pressure seepage test device for the interlayer waterproof bonding layer of asphalt pavement according to claim 1, characterized in that, The data acquisition and display unit (21) includes a computer, a data logger, an embedded acquisition display or a programmable control terminal, and has a pressure signal input terminal, a mass signal input terminal, a display module and a data storage module, used to generate data on the changes of pressure, cumulative seepage volume and seepage rate over time.

10. A method for testing the pressure seepage of the interlayer waterproof bonding layer of asphalt pavement, based on the pressure seepage testing device for the interlayer waterproof bonding layer of asphalt pavement according to any one of claims 1-9, characterized in that, Includes the following steps: Step 1, test preparation and instrument zeroing: check the integrity of the separate pressurized water chamber (5), pressurized water chamber water supply pipe (6), water chamber mounting base (7), detachable and washable connector (25), upper pressure plate perimeter sealing strip (16) and pressure system, put the pressure system in the depressurized state, and zero and calibrate the electronic balance (20) and data acquisition and display unit (21); Step 2, prepare and install the specimen and seal the edges: Apply the specified amount of asphalt pavement interlayer waterproof bonding material evenly to the upper surface of the cement concrete slab, cure it to the specified state to form a specimen, and the cement concrete slab serves as the bearing layer; place the specimen in the specimen installation space (29) between the upper pressure plate (4) and the lower pressure plate (2) with the waterproof bonding layer facing upward, seal the sides of the specimen, adjust the inner connecting adjusting screw (18) and adjusting nut (19) to make the sealing strip (16) around the upper pressure plate press the specimen, and then fix the clamping structure by the outer fixing screw (8) and fixing nut (9); Step 3, connect the water chamber and inject the test liquid: connect the separate pressurized water chamber (5) to the water chamber mounting base (7) through the pressurized water chamber water supply pipe (6), inject the test liquid into the separate pressurized water chamber (5) through the pressurized water injection port (27), remove the gas in the connecting pipe and seal the pressurized water injection port (27). Step 4, low-pressure leak detection, programmed pressurization and data acquisition: Start the air compressor or high-pressure pump (10), first check the sealing of each connection and the periphery of the specimen with low pressure, and after confirming that there is no bypass leakage, adjust the test pressure according to the preset program; based on the test assumption that the asphalt pavement surface layer is permeable, the test liquid is directly applied to the upper surface of the waterproof bonding layer through the pressurized water chamber (5) via the pressurized water chamber water supply pipe (6) and the water chamber mounting seat (7), and the liquid seeping from the bottom of the specimen enters the water collection tank (17) through the square drainage hole (24). The data acquisition and display unit (21) records the pressure, the mass of collected water and the sampling time simultaneously; Step 5, pressure relief and disassembly, specimen drying and evaluation: After the test, release the system pressure through the pressure regulating valve (12) and the safety pressure relief valve (14). After confirming that the pressure is completely relieved, remove the pressurized water chamber water supply pipe (6) and the specimen, remove the free water on the surface of the specimen and weigh the wet mass of the specimen using an electronic balance (20); dry the specimen at the specified temperature for the specified time, and weigh the dry mass after cooling. Determine the water absorption mass of the specimen by the difference between the wet mass and the dry mass; determine the collected water mass by the mass increment in the water collection tank (17); clean the separate pressurized water chamber (5), the detachable and washable joint (25), the water chamber mounting seat (7) and the water collection tank (17), and evaluate the interlayer waterproofing performance of the asphalt pavement based on the collected pressure, collected water mass, specimen water absorption mass, seepage rate and initial seepage time.

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