A device and method for measuring water seepage coefficient of road surface

Abstract

The present invention relates to a road maintenance device, and in particular to a road surface water permeability coefficient measuring device and measuring method, the measuring device comprising: a trailer equipped with a detection tire; a wireless air pressure sensor is provided on the detection tire; the wireless air pressure sensor is used to measure the gas pressure when the detection tire contacts the road surface; the wireless air pressure sensor is connected to a data analysis system. The road surface water permeability coefficient measuring device and measuring method provided by the present invention can perform large-scale rapid detection of the road surface water permeability performance of various road surface layers such as drainage asphalt pavement.

Description

Technical Field

[0001] The invention relates to the field of road maintenance devices, and in particular to a device and method for measuring a road surface water seepage coefficient. Background Art

[0002] In the field of road engineering, how to improve the function of the road surface and how to provide the society with road surface characteristics that are safer, more comfortable and more environmentally friendly have become new goals to pursue. Drainage asphalt pavement with large voids has outstanding advantages such as high anti-skid performance, low noise, suppression of water mist, prevention of water drift, and reduction of glare, reaching the top road performance in the existing asphalt pavement technology and becoming a pavement form that achieves a leap in the quality of road surface characteristics. After more than ten years of exploration and experimentation on drainage pavement, it has now entered the stage of promotion and application. However, with the construction and use of drainage pavement, its water permeability will gradually decay, and the degree of decay will vary greatly depending on the location.

[0003] At present, the on-site detection method of asphalt concrete pavement water permeability coefficient adopts the T 0971-2008 asphalt pavement water permeability coefficient test method in JTG E60-2008 "Highway Roadbed and Pavement Field Test Regulations". The indoor asphalt mixture water permeability coefficient detection method adopts the T 0730-2011 asphalt mixture water permeability test method in JTG E20-2011 "Highway Engineering Asphalt and Asphalt Mixture Test Regulations". The two detection methods have the same test principles, test steps, and instruments and equipment. The asphalt mixture water permeability coefficient test method uses a pavement water permeability meter, the main structure of which is a plexiglass measuring cylinder with a volume scale on the upper part, which is connected to the base through a capillary tube and has a valve. The diameter of the measuring cylinder, the diameter of the capillary tube, and the inner and outer diameters of the base are clearly specified in the specifications. During the test, the base and the pavement are sealed with sealing materials to prevent water from leaking from the base. The test method for water permeability coefficient is to record the time taken for the water surface to drop from the 100mL scale line to the 500mL scale line, and calculate the water permeability coefficient through the relationship between the amount of water infiltrating the road surface in the measuring cylinder and the time, and finally convert it into the amount of water that passes through the bottom seepage area of ​​the road permeability meter within 1 minute, in ml / min. The calculation formula is: C W =V2-V1 / t2-t1. Where: C Wis the pavement water permeability coefficient, ml / min; V1 is the scale of the measuring cylinder when the timing starts, ml, usually 100m L; V2 is the scale of the measuring cylinder when the timing stops, ml, usually 500ml; t1 is the time to start the timing, s; t2 is the time to stop the timing, s. At the beginning of the test, the tester visually observes the water surface scale, opens the water valve switch and starts the stopwatch; at the end of the test, the tester visually observes the water surface scale, closes the water valve switch and stops the stopwatch. In actual operation, due to the reaction time required by human hands and eyes, there will be a timing error of about 1s between the two operations of opening and closing the water valve and starting and stopping the stopwatch, which is difficult to avoid. The existing detection methods are all point measurement methods, the measurement procedures are relatively complicated, and the measured data can only represent the water permeability coefficient of the detected point, and cannot characterize the overall water permeability performance of the road. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a device and method for measuring the pavement water permeability coefficient, which can perform large-scale rapid detection of the pavement water permeability performance of various road surface layers such as drainage asphalt pavement.

[0005] Specifically, the present invention first provides a device for measuring the water permeability of a road surface, the device comprising: a trailer, the trailer is equipped with a detection tire 5; the detection tire 5 is provided with a wireless air pressure sensor 4; the wireless air pressure sensor 4 is used to measure the gas pressure when the pressure measuring port of the detection tire 5 contacts the road surface; the wireless air pressure sensor 4 is connected to a data analysis system. The device and method for measuring the water permeability coefficient of a road surface provided by the present invention can perform large-scale rapid detection of the water permeability of various road surface layers such as drainage asphalt pavement.

[0006] According to the device for measuring the road surface water permeability coefficient provided by the present invention, the test tire 5 is installed on the measuring device through an independent suspension system 2.

[0007] According to the device for measuring the road surface water permeability coefficient provided by the present invention, the detection tire 5 is a solid tire specially used for detection; the surface of the detection tire (5) has no pattern.

[0008] According to the device for measuring the road surface water permeability coefficient provided by the present invention, the diameter of the detection tire (5) is 60 to 120 cm, and the tire width is 140 to 200 mm; the size of the pressure measuring port arranged on the surface of the detection tire (5) is preferably 5 to 10 cm long, 3 to 5 cm wide, and 3 to 5 cm deep.

[0009] According to the device for measuring the road surface water permeability coefficient provided by the present invention, the pressure measuring port is arranged on the surface of the detection tire 5, and the wireless air pressure sensor 4 is arranged in the pressure measuring port.

[0010] According to the device for measuring the road surface water permeability coefficient provided by the present invention, the number of the detection tires 5 is 2 to 6; each of the detection tires 5 is provided with at least one wireless air pressure sensor 4, preferably 2 to 4.

[0011] The device for measuring the pavement water permeability coefficient provided by the present invention further comprises a trailer hook 1 and a trailer counterweight system 3; the trailer hook 1 is used to be connected to a towing vehicle, and the trailer counterweight system 3 is arranged on the trailer.

[0012] The device for measuring the road surface water permeability coefficient provided by the present invention further includes a speed sensor and a distance sensor arranged on the trailer.

[0013] According to the present invention, the skeleton of the measuring device adopts a metal shell surrounding plate, and the data of the wireless air pressure sensor, speed sensor and distance sensor are sent to the data receiving device, which is connected to the data analyzer via a data cable or wirelessly. The data analyzer is handheld or fixed in the traction vehicle.

[0014] The invention also provides a method for measuring the pavement water permeability coefficient, comprising a device for measuring the pavement water permeability coefficient.

[0015] According to the method for determining the pavement water permeability coefficient provided by the present invention, the method comprises:

[0016] 1) Off-site calibration, using the measuring device to test the calibration section, obtain the air pressure, and obtain the average air pressure in the section to be tested at the test speed;

[0017] 2) Indoor calibration, connect the air compressor to the sealing box, fix the sealing box on the surface of the rutting plate specimen with a water permeability coefficient of 0, adjust the power of the air compressor so that the air pressure in the sealing box reaches the average air pressure, and obtain the air compressor power; remove the sealing box, measure the rutting plate specimens with different water permeability coefficients under the air compressor power, and obtain the test air pressure; obtain the air pressure-water permeability coefficient curve according to the test air pressure and the water permeability coefficient;

[0018] 3) On-site testing, using the measuring device to test the road section to be tested at the test vehicle speed to obtain the air pressure of the road section to be tested;

[0019] 4) Data processing: obtaining the water permeability coefficient of the road section to be tested based on the acquired air pressure of the road section to be tested and the air pressure-water permeability coefficient curve.

[0020] The method for determining the pavement water permeability coefficient provided by the present invention comprises:

[0021] 1) Off-site calibration

[0022] The measuring device is connected to a traction vehicle, and a 50-100m section is selected as a calibration section in the section to be tested. The calibration section is preferably a section with a small water permeability coefficient or a dense and impermeable section. The water permeability coefficient of the calibration section is tested in advance using a water permeability meter; the traction vehicle is driven at a constant speed of 20-40km / h, preferably 30km / h, 40-50km / h, preferably 45km / h, 50-70km / h, preferably 60km / h, with the measuring device passing through the calibration section, and the air pressure is obtained. The instantaneous maximum value of the air pressure is taken as the calculated pressure value, and the average air pressure P in the section to be tested at different speeds is calculated. 30 , P 45 , P 60 ;

[0023] 2) Indoor calibration

[0024] Connect the air compressor to the sealing box; measure the rutting plate specimens with known water permeability coefficients; preferably, increase the number of rutting plate specimens within the estimated target water permeability coefficient range, and the number of rutting plate specimens with different water permeability coefficients is ≥5, fix the sealing box on the surface of the rutting plate specimen with a water permeability coefficient of 0, and adjust the power of the air compressor so that the air pressure in the sealing box reaches P 30 , P 45 , P 60 , record the air compressor power W at each air pressure 30 , W 45 , W 60 ;

[0025] Remove the sealing box and set the air compressor power W 30 , W 45 , W 60 The rutting plate specimens with different water permeability coefficients were measured respectively to obtain the test air pressure of each rutting plate specimen; the air pressure-water permeability coefficient curve was drawn according to the test air pressure and the water permeability coefficient value, and C 30 , C 45 , C 60 Three air pressure-water permeability curves, C v =f(x)

[0026] 3) On-site testing

[0027] Connect the measuring device to the towing vehicle, determine the testing speed (select from 30km / h, 45km / h, 60km / h) according to the length of the testing section and the traffic volume, and let the vehicle drive at a constant speed on the testing section to obtain air pressure data;

[0028] 4) Data processing

[0029] The acquired air pressure data is processed and analyzed, and one rotation of the vehicle tire is defined as a single cycle. The stored information includes the average tire pressure maximum value T of the four pressure sensors after the i-th single cycle of the j-th tire. j P i , vehicle travel distance m i , the time of the i-th single cycle is t i , wheel diameter d and test vehicle speed V t is a known parameter, m from the test origin i Water seepage coefficient C at distance mi The calculation formula is:

[0030]

[0031] C mi =f(P mi )

[0032] Where: P mi is the distance from the test origin m i The average pressure at the distance;

[0033] α t is the temperature correction factor.

[0034] The present invention also provides the application of the pavement water permeability coefficient determination device or the pavement water permeability coefficient determination method in the large-scale rapid detection of the void connectivity performance and water permeability coefficient of the pavement preferably large-pore drainage asphalt concrete pavement.

[0035] The beneficial effects of the present invention are at least that: the large-area rapid determination device and determination method of road surface water permeability provided by the present invention can rapidly detect the water permeability of various road surface layers. The present invention can reduce human errors, has a simple measurement procedure, and characterizes the water permeability of the entire road, and can rapidly, large-area, and accurately determine the water permeability coefficient of drainage asphalt pavement. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. It is obvious that the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0037] Figure 1 Schematic diagram of a device for measuring pavement water permeability coefficient in an embodiment of the present invention.

[0038] Figure 2 Schematic diagram of the detection tire in the device for measuring the road surface water permeability coefficient in an embodiment of the present invention.

[0039] Among them, 1-trailer hook; 2-independent suspension system; 3-trailer counterweight system; 4-wireless air pressure sensor; 5-tire detection. DETAILED DESCRIPTION

[0040] To make the purpose, technical scheme and advantages of the embodiment of the present invention clearer, the technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiment of the present invention. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention. If specific techniques or conditions are not specified in the embodiment, they are carried out according to the techniques or conditions described in the literature in this area, or according to the product specification. If the manufacturer is not specified in the reagents or instruments used, they are all conventional products that can be purchased through regular channels.

[0041] The method for determining the pavement water permeability coefficient according to a preferred embodiment of the present invention comprises:

[0042] 1) Off-site calibration

[0043] The measuring device is connected to a traction vehicle, and a 50-100m section is selected as a calibration section in the section to be tested. The calibration section is preferably a section with a small water permeability coefficient or a dense and impermeable section. The water permeability coefficient of the calibration section is tested in advance using a water permeability meter; the traction vehicle is driven at a constant speed of 20-40km / h, preferably 30km / h, 40-50km / h, preferably 45km / h, 50-70km / h, preferably 60km / h, with the measuring device passing through the calibration section, and the air pressure is obtained. The instantaneous maximum value of the air pressure is taken as the calculated pressure value, and the average air pressure P in the section to be tested at different speeds is calculated. 30 , P 45 , P 60 ;

[0044] 2) Indoor calibration

[0045] Connect the air compressor to the sealing box; measure the rutting plate specimens with known water permeability coefficients; preferably, increase the number of rutting plate specimens within the estimated target water permeability coefficient range, and the number of rutting plate specimens with different water permeability coefficients is ≥5, fix the sealing box on the surface of the rutting plate specimen with a water permeability coefficient of 0, and adjust the power of the air compressor so that the air pressure in the sealing box reaches P 30 , P 45 , P 60 , record the air compressor power W at each air pressure 30 , W 45 , W 60 ;

[0046] Remove the sealing box and set the air compressor power W 30 , W 45 , W 60The rutting plate specimens with different water permeability coefficients were measured to obtain the test air pressure of each rutting plate specimen; the air pressure-water permeability coefficient curve was drawn according to the test air pressure and the water permeability coefficient value, and three air pressure-water permeability coefficient curves were obtained respectively, among which the water permeability coefficient is C 30 , C 45 , C 60 , the curve is C v =f(x), where x is the air pressure at a vehicle speed of v;

[0047] 3) On-site testing

[0048] Connect the measuring device to the towing vehicle, determine the testing speed (select from 30km / h, 45km / h, 60km / h) according to the length of the testing section and the traffic volume, and let the vehicle drive at a constant speed on the testing section to obtain air pressure data;

[0049] 4) Data processing

[0050] The acquired air pressure data is processed and analyzed, and one rotation of the vehicle tire is defined as a single cycle. The stored information includes the average tire pressure maximum value T of the four pressure sensors after the i-th single cycle of the j-th tire. j P i , vehicle travel distance m i , the time of the i-th single cycle is t i , wheel diameter d and selected test speed V t is a known parameter, m from the test origin i Water seepage coefficient C at distance mi The calculation formula is:

[0051]

[0052] C mi =f(P mi )

[0053] Where: P mi is the distance from the test origin m i The average pressure at the distance;

[0054] α t is the temperature correction factor.

[0055] Example 1

[0056] This embodiment provides a device for measuring the water permeability coefficient of a road surface (such as Figure 1 and Figure 2), comprising: a trailer hook 1 arranged on the trailer, used to be connected to the towing vehicle; an independent suspension system 2 arranged under the trailer, and a detection tire 5 connected to the independent suspension system 2; the detection tire 5 is a solid detection tire with no pattern on the surface, and a pressure measuring port is arranged on the surface of the detection tire 5, and a wireless air pressure sensor 4 is arranged in the pressure measuring port; the trailer is also provided with a trailer counterweight system 3, a speed sensor and a distance sensor; the wireless air pressure sensor 4 is connected to the data analysis system; the number of detection tires 5 is 4; each detection tire 5 is provided with 4 wireless air pressure sensors 4; the diameter of the detection tire 5 is 80cm, and the tire width is 180mm; the dimensions of the pressure measuring port arranged on the surface of the detection tire 5 are 6cm long, 4cm wide and 4cm deep.

[0057] This embodiment also provides a method for quickly determining a road surface water permeability coefficient, comprising:

[0058] (1) Off-site calibration

[0059] The measuring device was tested on a 50m impermeable asphalt road surface by a tractor. The tire used in the measuring device had a diameter of 200cm. The tire passed through the calibration section for 8 cycles, and each tire obtained 32 P 30 , P 45 , P 60 The peak data is shown in the following table:

[0060] Table 1 Off-site calibration test structure

[0061]

[0062] By calculating the average values ​​of the four tires, we can obtain P30 as 105.4 kPa, P40 as 237.27 kPa, and P60 as 400.08 kPa.

[0063] (2) Indoor calibration

[0064] This embodiment uses a Roddy Z-1500 series air compressor, which is connected to a sealing box to test on a rutting board with a water permeability coefficient of 0. The power of the air compressor at 105.4kPa, 237.27kPa, and 400.08kPa is 3.3kW, 7.46kW, and 12.58kW, respectively. By adjusting the grading of the mineral material, rutting board specimens with water permeability coefficients of 523ml / min, 1155ml / min, 1870ml / min, 3680ml / min, and 5478ml / min are produced. The rutting board is tested with an air compressor of 3.3kW, 7.46kW, and 12.58kW, respectively. The results are shown in the following table:

[0065] Table 2 Indoor calibration test results

[0066]

[0067] (3) On-site testing

[0068] The above-mentioned measuring device is used for on-site testing. The on-site testing area of ​​this embodiment is selected in the drainage pavement test section of the South Third Ring Road in Shijiazhuang City, Hebei Province. The test section is 3km long and is divided into three sections: S1, S2, and S3 for testing. The length of each section is 1km. The test speeds are 30km / h, 45km / h, and 60km / h respectively. The average air pressure value of 50m in each test section within each kilometer is a test unit. The data obtained are shown in the following table:

[0069] Table 3 On-site test results

[0070]

[0071]

[0072] (4) Data processing

[0073] By matching the above data with the fitting equation and substituting it into the above equation, the water permeability coefficient of each unit in each section can be obtained, as shown in the following table:

[0074] Table 3 Data processing results

[0075]

[0076] This embodiment also provides an accuracy evaluation of the above-mentioned road surface water permeability coefficient rapid determination method, the specific method is:

[0077] The water permeability coefficient of the measured road section was re-tested using a water seepage meter. The re-test locations were selected as units U5, U7, U11, and U18 of the S1 section, units U3, U6, U9, and U12 of the S2 section, and units U4, U7, U10, and U13 of the S3 section. The re-test results are shown in the following table:

[0078] Table 3 Retest results

[0079]

[0080] Through the above comparative test results, it can be seen that the water permeability coefficient tested by this device is slightly different from the test results of traditional testing instruments, and this equipment has high detection accuracy.

[0081] Although the present invention has been described in detail above with general descriptions and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements may be made thereto based on the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection claimed by the present invention.

Claims

1. A method for determining a road surface water permeability coefficient, characterized in that: The determination method comprises: 1) Off-site calibration: Use a measuring device to test the calibration section, obtain the air pressure, and obtain the average air pressure in the section to be tested at the test speed; 2) Indoor calibration, connect the air compressor to the sealing box, fix the sealing box on the surface of the rutting plate specimen with a water permeability coefficient of 0, adjust the power of the air compressor so that the air pressure in the sealing box reaches the average air pressure, and obtain the air compressor power; remove the sealing box, measure the rutting plate specimens with different water permeability coefficients under the air compressor power, and obtain the test air pressure; obtain the air pressure-water permeability coefficient curve according to the test air pressure and the water permeability coefficient; 3) On-site testing, using the measuring device to test the road section to be tested at the test vehicle speed to obtain the air pressure of the road section to be tested; 4) data processing, obtaining the water permeability coefficient of the road section to be tested according to the acquired air pressure of the road section to be tested and the air pressure-water permeability coefficient curve; The measuring device comprises: a trailer, on which a detection tire (5) is installed; a wireless air pressure sensor (4) is provided on the detection tire (5); the wireless air pressure sensor (4) is used to measure the gas pressure when the pressure measuring port of the detection tire (5) contacts the road surface; and the wireless air pressure sensor (4) is connected to a data analysis system.

2. The method for determining the pavement water permeability coefficient according to claim 1, characterized in that: The test tire (5) is mounted on the measuring device via an independent suspension system (2).

3. The method for determining the pavement water permeability coefficient according to claim 1, characterized in that: The detection tire (5) is a solid tire specially used for detection; the surface of the detection tire (5) has no pattern.

4. The method for determining the pavement water permeability coefficient according to claim 1, characterized in that: A pressure measuring port is arranged on the surface of the detection tire (5), and the wireless air pressure sensor (4) is arranged in the pressure measuring port.

5. The method for determining the pavement water permeability coefficient according to claim 4, characterized in that: The number of the detection tires (5) is 2 to 6; each detection tire (5) is provided with at least one wireless air pressure sensor (4).

6. The method for determining the pavement water permeability coefficient according to claim 5, characterized in that: Each of the detection tires (5) is provided with 2 to 4 of the wireless air pressure sensors (4).

7. The method for determining the pavement water permeability coefficient according to any one of claims 1 to 6, characterized in that: It also comprises a trailer hook (1) and a trailer counterweight system (3); the trailer hook (1) is used to be connected to a towing vehicle, and the trailer counterweight system (3) is arranged on the trailer.

8. The method for determining the pavement water permeability coefficient according to any one of claims 1 to 6, characterized in that: The vehicle also includes a speed sensor and a distance sensor which are arranged on the trailer.

9. Application of the method for determining the pavement water permeability coefficient according to any one of claims 1 to 8 in large-scale rapid detection of the void connectivity and water permeability coefficient of a pavement.

10. The use according to claim 9, characterized in that: Application in large-scale rapid detection of void connectivity and water permeability coefficient of large-pore drainage asphalt concrete pavement.

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