CN107807044B - Test device and method for evaluating changes of middle and rear modulus of asphalt mixture before immersion - Google Patents
Test device and method for evaluating changes of middle and rear modulus of asphalt mixture before immersion Download PDFInfo
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- CN107807044B CN107807044B CN201710875892.3A CN201710875892A CN107807044B CN 107807044 B CN107807044 B CN 107807044B CN 201710875892 A CN201710875892 A CN 201710875892A CN 107807044 B CN107807044 B CN 107807044B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/08—Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/02—Details
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/0014—Type of force applied
- G01N2203/0016—Tensile or compressive
- G01N2203/0019—Compressive
Abstract
The invention discloses a test device and a method for evaluating the middle-rear modulus change of an asphalt mixture before immersion, wherein a power device is positioned at the top of an environment box, the output end of the power device is connected with the upper end of a pressure shaft, the lower end of the pressure shaft is provided with a connector for connecting a pressure probe and a closed cover plate, the closed cover plate covers an opening at the top of a test pool, a base is positioned at the bottom of the environment box, the upper end of a bearing shaft is connected with the bottom of the test pool, the lower end of the bearing shaft is fixed on the base, the bottom of the test pool is provided with a rubber base, a side limiting cylinder is positioned on the rubber base, the side of the test pool is provided with an air suction opening, a vacuum pump is communicated with the air suction opening, the top of the test pool is provided with a water inlet communicated with an external water source, and the bottom of the test pool is, Modulus changes before, during and after immersion under both confined and unconfined constraints.
Description
Technical Field
The invention belongs to the field of asphalt performance detection, and relates to a test device and a method for evaluating the change of the middle modulus and the rear modulus of an asphalt mixture before immersion.
Background
In recent years, the highway industry of China is developed rapidly, and particularly, more than 90% of high-grade pavements newly built every year are all asphalt pavements. While highway industry is developing at a high speed, a series of problems are also sequentially generated, and asphalt pavement water damage is one of the more prominent problems. At present, various evaluation tests and methods for the water damage resistance of asphalt pavements at home and abroad have some defects, for example, the difference of the water damage resistance of the asphalt pavements under the conditions of local loads and full-section loads under the conditions of limited constraint and no limited constraint is not considered. The invention provides a test device for testing the change of the middle and rear modulus of an asphalt mixture before and after immersion, which can be used for evaluating the water damage resistance of different asphalt pavements under different conditions.
Usually, natural precipitation is got rid of through bituminous paving's cross slope, but the precipitation is too big, only relies on the cross slope can't accomplish the drainage, just can form ponding road surface and flood road surface, waits that precipitation stops bituminous paving and is in the bituminous paving and form the back bituminous paving that soaks when the saturated state. The index of the strength change of the asphalt pavement before, after and after water immersion has important significance for evaluating the water damage resistance of the asphalt pavement, preventing the water damage of the asphalt pavement and reasonably maintaining the pavement. China has made a great deal of research on the freeze-thaw splitting test for testing the water stability of asphalt mixtures. However, the existing tests and researches show the water damage resistance of the asphalt mixture by adopting the breaking tensile strength, so that the modulus change of the asphalt mixture under different conditions cannot be tested, and the strength change of the asphalt pavement cannot be analyzed in combination with the actual situation so as to carry out the water damage preventive maintenance of the asphalt pavement. The invention provides a test device for evaluating the change of the middle and rear modulus of an asphalt mixture before immersion, which can be used for evaluating the water damage resistance of different asphalt pavements under different conditions. The water damage resistance of the simulated asphalt pavement is evaluated by testing the modulus change of the same asphalt mixture test piece before, during and after immersion under different conditions (local load, limited constraint or no limited constraint).
The existing test for testing the water damage resistance of the asphalt pavement has defects, and a test device and a determination method for evaluating the modulus change of the asphalt pavement before, after and after water immersion under different conditions are lacked. The main disadvantages of the prior art are as follows:
(1) in the prior art, a freeze-thaw splitting test is generally adopted to test the water stability of the asphalt mixture, the existing test and research show the water damage resistance of the asphalt mixture by adopting the breaking tensile strength, neglect the water damage caused by the limit of the compressive strength, and in the actual situation, the asphalt pavement is often subjected to pressure instead of tension, so that the defect exists in showing the water damage resistance of the asphalt mixture by only adopting the breaking tensile strength. The conditions of the freeze-thaw splitting test are harsh, and the test times are dozens of times or even hundreds of times, which is tedious.
(2) In the prior art, the damage strength ratio of an asphalt mixture test piece before and after freeze thawing is generally only used as an evaluation index, the modulus change of the asphalt mixture test piece before, during and after soaking is ignored, and the influence of the constraint condition of the test piece on the test result is ignored. Therefore, the modulus change of the asphalt mixture at each stage of soaking cannot be determined precisely, and the water damage resistance of the asphalt pavement cannot be evaluated accurately.
(3) In the prior art, a fixed temperature is generally adopted for testing, and the thinking of influencing the water damage resistance of the asphalt mixture on the temperature factor is lacked, so the universality is not strong, and the water damage resistance of the asphalt pavement at different temperatures cannot be accurately evaluated.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a test device and a method for evaluating the modulus change of an asphalt mixture before, during and after soaking, the device and the method can measure the modulus change of the asphalt mixture before, during and after soaking under full section load, lateral constraint and no lateral constraint at different temperatures.
In order to achieve the purpose, the test device for evaluating the modulus change before, after and after the asphalt mixture is soaked in water comprises a computer, a vacuum pump, an environment box, a temperature control device for controlling the environment box, a power device, a pressure shaft, a side limiting barrel, a sealing cover plate, a test pool, a base, a bearing shaft and a pressure probe capable of providing full-section load, wherein the power device, the pressure shaft, the side limiting barrel, the sealing cover plate, the test pool, the base and the bearing shaft are arranged in the environment box;
the power device is located at the top of the environment box, the output end of the power device is connected with the upper end of the pressure shaft, the lower end of the pressure shaft is provided with a connector used for connecting a pressure probe and a sealing cover plate, the sealing cover plate covers the top opening of the test pool, the base is located at the bottom of the environment box, the upper end of the pressure bearing shaft is connected with the bottom of the test pool, the lower end of the pressure bearing shaft is fixed on the base, the bottom of the test pool is provided with a rubber base, the side limiting cylinder is located on the rubber base, the side face of the test pool is provided with an air suction opening, the vacuum pump is communicated with the air suction opening, the top of the test pool is provided with a water inlet communicated with an external water source, the bottom of the test pool is.
The connector is a threaded interface.
A water outlet of the test pool is provided with a drain valve;
a water inlet valve is arranged at the water inlet of the test pool;
an air exhaust valve is arranged at the air exhaust port of the test pool.
An annular groove is formed in the rubber base, and the lower end of the side limiting barrel is embedded in the annular groove.
The bottom of the closed cover plate is provided with a rubber groove matched with the wall surface of the opening at the top of the test pool.
The vacuum pump is communicated with an air suction opening on the test pool through a rubber water pipe.
The test method for evaluating the modulus change before, after and after the asphalt mixture is soaked in water comprises the following steps:
1a) placing a to-be-tested piece on a rubber base, and then adjusting the temperature in an environment box;
2a) installing a pressure probe on the connector, closing the drain valve, the water inlet valve and the air exhaust valve to simulate the state of the to-be-tested piece before soaking, setting the compression amount of the to-be-tested piece to be 10mm by the computer, driving a pressure shaft by a power device to compress the to-be-tested piece, and obtaining a pressure value P by the pressure probe when the compression amount of the to-be-tested piece is 10mm1(ii) a Reducing the position of the pressure shaft, removing the pressure probe, mounting the sealing cover plate on the connector, adjusting the position of the pressure shaft to tightly seal the sealing cover plate and the test pool, opening the air exhaust valve, vacuumizing the test pool by a vacuum pump to keep the test pool in a vacuum state, opening the water inlet valve to make water in an external water source enter the test pool and make the water level in the test pool be 3cm higher than the top of the to-be-tested piece, closing the water inlet valve, standing for 10min,enabling a to-be-tested piece to be in a water saturation state to simulate the state that the to-be-tested piece is immersed in water, then restoring the position of a pressure shaft, dismantling a sealing cover plate, installing a pressure probe on a connector, setting the compression amount of the to-be-tested piece to be 10mm, driving the pressure shaft by a power device to apply load to the to-be-tested piece, and when the compression amount of the to-be-tested piece is 10mm, measuring by the pressure probe to obtain a pressure value P2(ii) a Then reducing the position of the pressure shaft, disconnecting the vacuum pump, opening the drain valve and the exhaust valve to drain water in the test pool, standing for 10min to simulate the state of the test piece to be tested after soaking, then compressing the test piece to be tested through the pressure shaft, and obtaining a pressure value P measured by the pressure probe when the compression amount of the test piece to be tested is 10mm3；
3a) The modulus reduction rate of the tested piece in the water immersion is α under the condition of no lateral limit constraint1And modulus reduction rate α of test piece after immersion in water2Comprises the following steps:
the test method for evaluating the modulus change before, after and after the asphalt mixture is soaked in water comprises the following steps:
1b) placing a side limiting cylinder on a rubber base, placing a to-be-tested part in the side limiting cylinder, and adjusting the temperature in an environment box;
2b) installing a pressure probe on the connector, closing the drain valve, the water inlet valve and the air exhaust valve to simulate the state of the to-be-tested piece before soaking, setting the compression amount of the to-be-tested piece to be 10mm by the computer, driving a pressure shaft by a power device to compress the to-be-tested piece, and obtaining a pressure value P by the pressure probe when the compression amount of the to-be-tested piece is 10mm11(ii) a Reducing the position of the pressure shaft, removing the pressure probe, installing the sealing cover plate on the connector, adjusting the position of the pressure shaft to make the sealing cover plate tightly close to the test cell, opening the air extraction valve, and vacuum pumpingVacuumizing the test pool to enable the test pool to be in a vacuum state, opening the water inlet valve to enable water in an external water source to enter the test pool, enabling the water level in the test pool to be 3cm higher than the top of the to-be-tested piece, closing the water inlet valve, standing for 10min to enable the to-be-tested piece to be in a water saturation state to simulate the state that the to-be-tested piece is immersed in water, reducing the position of the pressure shaft, detaching the sealing cover plate, installing the pressure probe on the connector, setting the compression amount of the to-be-tested piece to be 10mm, driving the pressure shaft to apply load to the to-be-tested piece by the power device, and enabling the pressure value obtained by the pressure probe when the compression amount of the to-be-tested piece is21(ii) a Then reducing the position of the pressure shaft, disconnecting the vacuum pump, opening the drain valve and the exhaust valve to drain water in the test pool, standing for 10min to simulate the state of the test piece to be tested after soaking, then compressing the test piece to be tested through the pressure shaft, and obtaining a pressure value P measured by the pressure probe when the compression amount of the test piece to be tested is 10mm31；
3b) The modulus reduction rate of the test piece to be tested in the water is α under the lateral limit constraint condition11And modulus reduction rate α of test piece after immersion in water21Comprises the following steps:
the test method for evaluating the modulus change before, after and after the asphalt mixture is soaked in water comprises the following steps:
1c) placing a to-be-tested piece on a rubber base, and then adjusting the temperature in an environment box to enable the temperature in the environment box to be T1；
2c) Installing a pressure probe on the connector, closing the drain valve, the water inlet valve and the air exhaust valve to simulate the state of the to-be-tested piece before soaking, setting the compression amount of the to-be-tested piece to be 10mm by the computer, compressing the to-be-tested piece by the power device driving the pressure shaft, and when the compression amount of the to-be-tested piece is 10mmThe pressure value measured by the pressure probe is P12Reducing the position of the pressure shaft, removing the pressure probe, installing the sealing cover plate on the connector, adjusting the position of the pressure shaft to tightly seal the sealing cover and the test tank, opening the air extraction valve, vacuumizing the test tank by the vacuum pump to keep the test tank in a vacuum state, opening the water inlet valve to make water in an external water source enter the test tank and make the water level in the test tank higher than the top of the to-be-tested piece by 3cm, then closing the water inlet valve, standing for 10min to ensure that the to-be-tested piece is in a water saturation state so as to simulate the state that the to-be-tested piece is immersed in water, then reducing the position of the pressure shaft, removing the sealing cover plate, installing the pressure probe on the connector, setting the compression amount of the piece to be tested to be 10mm, driving the pressure shaft by the power device to apply load to the piece to be tested, and obtaining a pressure value P by the pressure probe when the compression amount of the piece to be tested is 10 mm.22(ii) a Then reducing the position of the pressure shaft, disconnecting the vacuum pump, opening the drain valve and the exhaust valve to drain water in the test pool, standing for 10min to simulate the state of the test piece to be tested after soaking, then compressing the test piece to be tested through the pressure shaft, and obtaining a pressure value P measured by the pressure probe when the compression amount of the test piece to be tested is 10mm32；
3c) To a temperature of T1Without lateral limit, the modulus reduction rate of the test piece in the water immersion is α12And modulus reduction rate α of test piece after immersion in water22Comprises the following steps:
4c) selecting a test piece, and adjusting the temperature in the environment box to T2Repeating the steps 2c) and 3c) to obtain a temperature T2Without lateral limit, the modulus reduction rate of the test piece in the water immersion is α1′And modulus reduction rate α of test piece after immersion in water2′Of the test pieceThe temperature influence coefficient λ is:
the invention has the following beneficial effects:
the test device and the method for evaluating the modulus change before, during and after the asphalt mixture is soaked in water regulate the environment in the test pool through the water inlet valve, the water discharge valve and the vacuum pump to simulate the state of the tested piece before, during and after the asphalt mixture is soaked in water, simulate the side limit constraint condition and the non-side limit constraint condition of the tested piece through installing or canceling the side limit cylinder, change the realization temperature through the environment box, and measure the modulus reduction rate of the tested piece in the soaking water, the modulus reduction rate of the tested piece after the test piece is soaked in water and the temperature influence coefficient of the tested piece through the matching of the power device, the pressure probe and the pressure shaft, have simple and convenient operation, and simultaneously indicate that the pressure probe in the invention is a pressure probe capable of providing full section load to measure the modulus change before, during and after the asphalt mixture is soaked in the different temperatures under the full section load, the side limit constraint and the non-side limit constraint, and furthermore, the water damage resistance of the asphalt pavement can be evaluated through the measured data, compared with the traditional freeze-thaw splitting test, the method is simple to operate, the test time and the input manpower and material resources are relatively less, meanwhile, the operation error caused by artificial factors is avoided, and the evaluation accuracy is higher. In addition, the invention adopts the reduction rate of the modulus of the test piece in the soaking water and the reduction rate of the modulus after the soaking water as evaluation indexes to make up the defect that the water damage resistance of the asphalt mixture is expressed only by adopting the breaking tensile strength.
Drawings
Fig. 1 is a schematic structural view of the present invention after installation of a closure flap 9;
FIG. 2 is a schematic structural view of the present invention after the pressure probe 19 is installed;
FIG. 3 is a schematic view of the rubber base 16 of the present invention;
FIG. 4 is a schematic structural view of the side confining barrel 7 of the present invention;
FIG. 5 is a schematic view showing the structure of a test cell 8 according to the present invention;
fig. 6 is a schematic structural view of the closing cover plate 9 of the present invention.
Wherein, 1 is an environment box, 2 is a vacuum pump, 3 is a computer, 4 is a base, 5 is a pressure bearing shaft, 6 is an air extraction port, 7 is a side limiting cylinder, 8 is a test pool, 9 is a closed cover plate, 10 is a temperature control device, 11 is a pressure shaft, 12 is a power device, 13 is a connector, 14 is a water inlet, 15 is a to-be-tested piece, 16 is a rubber base, 17 is a drain valve, 18 is a water outlet, 19 is a pressure probe, 20 is an annular groove, 21 is an air extraction valve, 22 is a water inlet valve, and 23 is a rubber groove.
Detailed Description
The invention is described in further detail below with reference to the accompanying drawings:
referring to fig. 1, the test device for evaluating modulus change before, after and after asphalt mixture is soaked in water comprises a computer 3, a vacuum pump 2, an environment box 1, a temperature control device 10 for controlling the environment box 1, a power device 12 arranged in the environment box 1, a pressure shaft 11, a side limiting cylinder 7, a closed cover plate 9, a test pool 8, a base 4, a pressure bearing shaft 5 and a pressure probe 19 capable of providing full section load; the power device 12 is located at the top of the environment box 1, the output end of the power device 12 is connected with the upper end of the pressure shaft 11, the lower end of the pressure shaft 11 is provided with a connector 13 used for connecting a pressure probe 19 and a sealing cover plate 9, the sealing cover plate 9 covers the top opening of the test pool 8, the base 4 is located at the bottom of the environment box 1, the upper end of the pressure bearing shaft 5 is connected with the bottom of the test pool 8, the lower end of the pressure bearing shaft 5 is fixed on the base 4, the bottom of the test pool 8 is provided with a rubber base 16, the side limiting cylinder 7 is located on the rubber base 16, the side face of the test pool 8 is provided with an air suction opening 6, the vacuum pump 2 is communicated with the air suction opening 6, the top of the test pool 8 is provided with a water inlet 14 communicated with an external water source, the bottom of the test pool 8 is provided with a.
The connector 13 is a screw interface. A drain valve 17 is arranged at a water outlet 18 of the test pool 8; a water inlet valve 22 is arranged at the water inlet 14 of the test pool 8; an air extraction valve 21 is arranged at the air extraction port 6 of the test pool 8; an annular groove 20 is formed in the rubber base 16, and the lower end of the side limiting cylinder 7 is embedded in the annular groove 20; the bottom of the closed cover plate 9 is provided with a rubber groove 23 matched with the wall surface of the top opening of the test cell 8; the vacuum pump 2 is communicated with an air suction port 6 on the test cell 8 through a rubber water pipe.
The side limiting cylinder 7 is used for providing side limitation for the to-be-tested piece 15 during testing under the side limiting constraint condition, the to-be-tested piece 15 is located in the side limiting cylinder 7 during testing under the side limiting constraint condition, and the to-be-tested piece 15 is directly placed on the rubber base 16 during testing under the non-side limiting constraint condition.
During indoor test, the asphalt mixture is used for testing through a cylindrical test piece formed by a rotary compaction instrument to obtain a to-be-tested test piece 15, during outdoor test, a drill bit is used for coring and sampling to obtain the cylindrical test piece, and then the to-be-tested test piece 15 is kept stand for a period of time to be dried.
The pressure probe 19 is a pressure probe 19 capable of providing a local load.
Example one
The test method for evaluating the modulus change before, after and after the asphalt mixture is soaked in water comprises the following steps:
1a) placing a piece 15 to be tested on a rubber base 16, and then adjusting the temperature in the environment box 1;
2a) installing a pressure probe 19 on the connector 13, closing the drain valve 17, the water inlet valve 22 and the air suction valve 21 to simulate the state of the piece 15 to be tested before soaking, setting the compression amount of the piece 15 to be tested to be 10mm by the computer 3, driving the pressure shaft 11 by the power device 12 to compress the piece 15 to be tested, and measuring a pressure value P by the pressure probe 19 when the compression amount of the piece 15 to be tested is 10mm1(ii) a Reducing the position of the pressure shaft 11, removing the pressure probe 19, installing the sealing cover plate 9 on the connector 13, adjusting the position of the pressure shaft 11 to enable the sealing cover plate 9 and the test pool 8 to be tightly attached and sealed, opening the air exhaust valve 21, vacuumizing the test pool 8 by the vacuum pump 2 to enable the interior of the test pool 8 to be in a vacuum state, opening the water inlet valve 22 to enable the interior of an external water source to be in a vacuum stateThe water enters the test pool 8, the water level in the test pool 8 is higher than the top of the to-be-tested piece 15 by 3cm, then the water inlet valve 22 is closed, the test pool is kept still for 10min, the to-be-tested piece 15 is in a water saturation state to simulate the state that the to-be-tested piece 15 is immersed in water, then the position of the pressure shaft 11 is restored, the sealing cover plate 9 is removed, the pressure probe 19 is installed on the connector 13, the compression amount of the to-be-tested piece 15 is set to be 10mm, the power device 12 drives the pressure shaft 11 to apply load to the to-be-tested piece 15, and when the compression amount of the to-be-tested piece 15 is 10mm, the pressure value obtained by the pressure2(ii) a Then reducing the position of the pressure shaft 11, disconnecting the vacuum pump 2, opening the drain valve 17 and the extraction valve 21 to drain water in the test cell 8, standing for 10min to simulate the state of the test piece 15 to be tested after soaking, then compressing the test piece 15 to be tested through the pressure shaft 11, and when the compression amount of the test piece 15 to be tested is 10mm, measuring a pressure value P by the pressure probe 193；
3a) The module reduction rate α of the test piece 15 to be tested immersed in water under the condition of no lateral limit constraint1And the modulus decrease rate α after the test piece 15 to be tested is soaked in water2Comprises the following steps:
example two
The test method for evaluating the modulus change before, after and after the asphalt mixture is soaked in water comprises the following steps:
1b) placing the side limiting cylinder 7 on a rubber base 16, placing a to-be-tested piece 15 in the side limiting cylinder 7, and then adjusting the temperature in the environment box 1;
2b) installing a pressure probe 19 on the connector 13, closing the drain valve 17, the inlet valve 22 and the suction valve 21 to simulate the state of the piece 15 to be tested before soaking, setting the compression amount of the piece 15 to be tested to 10mm by the computer 3, compressing the piece 15 to be tested by driving the pressure shaft 11 by the power device 12, and when the compression amount of the piece 15 to be tested is smaller than the compression amount of the piece 15 to be testedThe pressure value measured by the pressure probe 19 when the amount is 10mm is P11(ii) a Reducing the position of the pressure shaft 11, removing the pressure probe 19, installing the sealing cover plate 9 on the connector 13, adjusting the position of the pressure shaft 11 to enable the sealing cover plate 9 and the test pool 8 to be tightly attached and sealed, opening the extraction valve 21, vacuumizing the test pool 8 by the vacuum pump 2 to enable the test pool 8 to be in a vacuum state, opening the water inlet valve 22 to enable water in an external water source to enter the test pool 8 and enable the water level in the test pool 8 to be higher than the top of the to-be-tested piece 15 by 3cm, then closing the water inlet valve 22, standing for 10min to enable the to-be-tested piece 15 to be in a water saturation state to simulate the to-be-tested piece 15 to be in a water immersion state, then reducing the position of the pressure shaft 11, removing the sealing cover plate 9, installing the pressure probe 19 on the connector 13, setting the compression amount of the to-be-tested piece 15 to be 10mm, driving the pressure shaft 11 by the power device 12 to apply load to the to, when the compression amount of the test piece 15 to be tested is 10mm, the pressure value measured by the pressure probe 19 is P21(ii) a Then reducing the position of the pressure shaft 11, disconnecting the vacuum pump 2, opening the drain valve 17 and the extraction valve 21 to drain water in the test cell 8, standing for 10min to simulate the state of the test piece 15 to be tested after soaking, then compressing the test piece 15 to be tested through the pressure shaft 11, and when the compression amount of the test piece 15 to be tested is 10mm, measuring a pressure value P by the pressure probe 1931；
3b) Under the lateral limit constraint condition, the module drop rate α in the immersion of the tested piece 1511And the modulus decrease rate α after the test piece 15 to be tested is soaked in water21Comprises the following steps:
EXAMPLE III
The test method for evaluating the modulus change before, after and after the asphalt mixture is soaked in water comprises the following steps:
1c) the test piece 15 is placed on a rubber base 16 and then adjustedThe temperature in the environmental chamber 1 is set to T1；
2c) Installing a pressure probe 19 on the connector 13, closing the drain valve 17, the water inlet valve 22 and the air suction valve 21 to simulate the state of the piece 15 to be tested before soaking, setting the compression amount of the piece 15 to be tested to be 10mm by the computer 3, driving the pressure shaft 11 by the power device 12 to compress the piece 15 to be tested, and measuring a pressure value P by the pressure probe 19 when the compression amount of the piece 15 to be tested is 10mm12Reducing the position of the pressure shaft 11, removing the pressure probe 19, installing the sealing cover plate 9 on the connector 13, adjusting the position of the pressure shaft 11 to enable the sealing cover plate 9 and the test pool 8 to be tightly attached and sealed, opening the extraction valve 21, vacuumizing the test pool 8 by the vacuum pump 2 to enable the test pool 8 to be in a vacuum state, opening the water inlet valve 22 to enable water in an external water source to enter the test pool 8 and enable the water level in the test pool 8 to be higher than the top of the to-be-tested piece 15 by 3cm, then closing the water inlet valve 22, standing for 10min to enable the to-be-tested piece 15 to be in a saturated state to simulate the to-be-tested piece 15 to be in a submerged state, then reducing the position of the pressure shaft 11, removing the sealing cover plate 9, installing the pressure probe 19 on the connector 13, setting the compression amount of the to-be-tested piece 15 to be 10mm, driving the pressure shaft 11 by the power device 12 to apply load to the to-, when the compression amount of the test piece 15 to be tested is 10mm, the pressure value measured by the pressure probe 19 is P22(ii) a Then reducing the position of the pressure shaft 11, disconnecting the vacuum pump 2, opening the drain valve 17 and the extraction valve 21 to drain water in the test cell 8, standing for 10min to simulate the state of the test piece 15 to be tested after soaking, then compressing the test piece 15 to be tested through the pressure shaft 11, and when the compression amount of the test piece 15 to be tested is 10mm, measuring a pressure value P by the pressure probe 1932；
3c) To a temperature of T1In time, the rate of the decrease of the modulus α in the immersion of the test piece 15 under test is not limited by the lateral constraint12And the modulus decrease rate α after the test piece 15 to be tested is soaked in water22Comprises the following steps:
4c) the test piece 15 is newly selected, and then the temperature in the environmental chamber 1 is adjusted to T2Repeating the steps 2c) and 3c) to obtain a temperature T2In time, the rate of the decrease of the modulus α in the immersion of the test piece 15 under test is not limited by the lateral constraint1′And the modulus decrease rate α after the test piece 15 to be tested is soaked in water2′Then, the temperature influence coefficient λ of the test piece 15 to be tested is:
Claims (7)
1. a test method for evaluating the modulus change before, after and after the asphalt mixture is soaked is characterized in that based on a test device for evaluating the modulus change before, after and after the asphalt mixture is soaked, the test device for evaluating the modulus change before, after and after the asphalt mixture is soaked comprises a computer (3), a vacuum pump (2), an environment box (1), a temperature control device (10) for controlling the environment box (1), a power device (12), a pressure shaft (11), a side limiting cylinder (7), a sealing cover plate (9), a test pool (8), a base (4), a pressure bearing shaft (5) and a pressure probe (19) capable of providing full-section load, wherein the power device (12), the pressure shaft (11), the side limiting cylinder (7), the sealing cover plate (9), the test pool (8;
the power device (12) is positioned at the top of the environment box (1), the output end of the power device (12) is connected with the upper end of the pressure shaft (11), the lower end of the pressure shaft (11) is provided with a connector (13) for connecting a pressure probe (19) and the sealing cover plate (9), the sealing cover plate (9) covers the top opening of the test pool (8), the base (4) is positioned at the bottom of the environment box (1), the upper end of the bearing shaft (5) is connected with the bottom of the test pool (8), the lower end of the bearing shaft (5) is fixed on the base (4), the bottom of the test pool (8) is provided with a rubber base (16), the side limiting cylinder (7) is positioned on the rubber base (16), the side surface of the test pool (8) is provided with an air suction opening (6), the vacuum pump (2) is communicated with the air suction opening (6), the top of the test pool (8) is provided with a water inlet (14) communicated, a water outlet (18) is arranged at the bottom of the test pool (8), and the computer (3) is connected with the output end of the pressure probe (19) and the control end of the power device (12);
the connector (13) is a threaded interface;
the method comprises the following steps:
1a) placing a piece (15) to be tested on a rubber base (16), and then adjusting the temperature in the environment box (1);
2a) installing a pressure probe (19) on a connector (13), closing a drain valve (17), a water inlet valve (22) and an air extraction valve (21) to simulate the state of a piece to be tested (15) before immersion, setting the compression amount of the piece to be tested (15) to be 10mm by a computer (3), driving a pressure shaft (11) by a power device (12) to compress the piece to be tested (15), and measuring a pressure value P by the pressure probe (19) when the compression amount of the piece to be tested (15) is 10mm1(ii) a Reducing the position of a pressure shaft (11), removing a pressure probe (19), installing a sealing cover plate (9) on a connector (13), adjusting the position of the pressure shaft (11), enabling the sealing cover plate (9) and a test pool (8) to be tightly attached and sealed, opening an air suction valve (21), vacuumizing the test pool (8) by a vacuum pump (2), enabling the interior of the test pool (8) to be in a vacuum state, opening a water inlet valve (22), enabling water in an external water source to enter the test pool (8), enabling the water level in the test pool (8) to be higher than the top of a to-be-tested piece (15) by 3cm, closing the water inlet valve (22), standing for 10min, enabling the to-be-tested piece (15) to be in a water saturation state to simulate the to-be-tested piece (15) to be in a water immersion state, reducing the position of the pressure shaft (11), removing the sealing cover plate (9), and installing the pressure probe (19) on the connector (13), then setting the compression amount of the piece to be tested (15) to be 10mm, driving a pressure shaft (11) by a power device (12) to apply load to the piece to be tested (15), and when the compression amount of the piece to be tested (15) is 10mm, measuring a pressure value P by a pressure probe (19)2(ii) a Then reducing the position of the pressure shaft (11), disconnecting the vacuum pump (2), opening the drain valve (17) and the extraction valve (21) to drain water in the test cell (8), standing for 10min to simulate the state of the test piece (15) after soaking, then compressing the test piece (15) through the pressure shaft (11), and when the compression amount of the test piece (15) is 10mm, measuring by the pressure probe (19) to obtain a pressure value P3；
3a) Without side limitUnder the constraint condition, the module drop rate α in the immersion of the test piece (15)1And the modulus reduction rate α of the test piece (15) after immersion2Comprises the following steps:
2. a test method for evaluating the modulus change before, after and after the asphalt mixture is soaked is characterized in that based on a test device for evaluating the modulus change before, after and after the asphalt mixture is soaked, the test device for evaluating the modulus change before, after and after the asphalt mixture is soaked comprises a computer (3), a vacuum pump (2), an environment box (1), a temperature control device (10) for controlling the environment box (1), a power device (12), a pressure shaft (11), a side limiting cylinder (7), a sealing cover plate (9), a test pool (8), a base (4), a pressure bearing shaft (5) and a pressure probe (19) capable of providing full-section load, wherein the power device (12), the pressure shaft (11), the side limiting cylinder (7), the sealing cover plate (9), the test pool (8;
the power device (12) is positioned at the top of the environment box (1), the output end of the power device (12) is connected with the upper end of the pressure shaft (11), the lower end of the pressure shaft (11) is provided with a connector (13) for connecting a pressure probe (19) and the sealing cover plate (9), the sealing cover plate (9) covers the top opening of the test pool (8), the base (4) is positioned at the bottom of the environment box (1), the upper end of the bearing shaft (5) is connected with the bottom of the test pool (8), the lower end of the bearing shaft (5) is fixed on the base (4), the bottom of the test pool (8) is provided with a rubber base (16), the side limiting cylinder (7) is positioned on the rubber base (16), the side surface of the test pool (8) is provided with an air suction opening (6), the vacuum pump (2) is communicated with the air suction opening (6), the top of the test pool (8) is provided with a water inlet (14) communicated, a water outlet (18) is arranged at the bottom of the test pool (8), and the computer (3) is connected with the output end of the pressure probe (19) and the control end of the power device (12);
the connector (13) is a threaded interface;
the method comprises the following steps:
1b) placing the side limiting cylinder (7) on a rubber base (16), then placing a to-be-tested piece (15) in the side limiting cylinder (7), and then adjusting the temperature in the environment box (1);
2b) installing a pressure probe (19) on a connector (13), closing a drain valve (17), a water inlet valve (22) and an air extraction valve (21) to simulate the state of a piece to be tested (15) before immersion, setting the compression amount of the piece to be tested (15) to be 10mm by a computer (3), driving a pressure shaft (11) by a power device (12) to compress the piece to be tested (15), and measuring a pressure value P by the pressure probe (19) when the compression amount of the piece to be tested (15) is 10mm11(ii) a Reducing the position of a pressure shaft (11), removing a pressure probe (19), installing a sealing cover plate (9) on a connector (13), adjusting the position of the pressure shaft (11), enabling the sealing cover plate (9) and a test pool (8) to be tightly attached and sealed, opening an air suction valve (21), vacuumizing the test pool (8) by a vacuum pump (2), enabling the interior of the test pool (8) to be in a vacuum state, opening a water inlet valve (22), enabling water in an external water source to enter the test pool (8), enabling the water level in the test pool (8) to be higher than the top of a to-be-tested piece (15) by 3cm, closing the water inlet valve (22), standing for 10min, enabling the to-be-tested piece (15) to be in a water saturation state to simulate the to-be-tested piece (15) to be in a water immersion state, reducing the position of the pressure shaft (11), removing the sealing cover plate (9), and installing the pressure probe (19) on the connector (13), then setting the compression amount of the piece to be tested (15) to be 10mm, driving a pressure shaft (11) by a power device (12) to apply load to the piece to be tested (15), and when the compression amount of the piece to be tested (15) is 10mm, measuring a pressure value P by a pressure probe (19)21(ii) a Then reducing the position of the pressure shaft (11), disconnecting the vacuum pump (2), opening the drain valve (17) and the extraction valve (21) to drain water in the test cell (8), standing for 10min to simulate the state of the test piece (15) after soaking, then compressing the test piece (15) through the pressure shaft (11), and when the compression amount of the test piece (15) is 10mm, measuring by the pressure probe (19) to obtain a pressure value P31；
3b) Under the condition of lateral limit constraint, the module reduction rate α in the immersed water of the test piece (15)11And the modulus reduction rate α of the test piece (15) after immersion21Comprises the following steps:
3. a test method for evaluating the modulus change before, after and after the asphalt mixture is soaked is characterized in that based on a test device for evaluating the modulus change before, after and after the asphalt mixture is soaked, the test device for evaluating the modulus change before, after and after the asphalt mixture is soaked comprises a computer (3), a vacuum pump (2), an environment box (1), a temperature control device (10) for controlling the environment box (1), a power device (12), a pressure shaft (11), a side limiting cylinder (7), a sealing cover plate (9), a test pool (8), a base (4), a pressure bearing shaft (5) and a pressure probe (19) capable of providing full-section load, wherein the power device (12), the pressure shaft (11), the side limiting cylinder (7), the sealing cover plate (9), the test pool (8;
the power device (12) is positioned at the top of the environment box (1), the output end of the power device (12) is connected with the upper end of the pressure shaft (11), the lower end of the pressure shaft (11) is provided with a connector (13) for connecting a pressure probe (19) and the sealing cover plate (9), the sealing cover plate (9) covers the top opening of the test pool (8), the base (4) is positioned at the bottom of the environment box (1), the upper end of the bearing shaft (5) is connected with the bottom of the test pool (8), the lower end of the bearing shaft (5) is fixed on the base (4), the bottom of the test pool (8) is provided with a rubber base (16), the side limiting cylinder (7) is positioned on the rubber base (16), the side surface of the test pool (8) is provided with an air suction opening (6), the vacuum pump (2) is communicated with the air suction opening (6), the top of the test pool (8) is provided with a water inlet (14) communicated, a water outlet (18) is arranged at the bottom of the test pool (8), and the computer (3) is connected with the output end of the pressure probe (19) and the control end of the power device (12);
the connector (13) is a threaded interface;
the method comprises the following steps:
1c) placing a piece (15) to be tested on a rubber base (16), and then adjusting the temperature in the environment box (1) to ensure that the temperature in the environment box (1)Is T1；
2c) Installing a pressure probe (19) on a connector (13), closing a drain valve (17), a water inlet valve (22) and an air extraction valve (21) to simulate the state of a piece to be tested (15) before immersion, setting the compression amount of the piece to be tested (15) to be 10mm by a computer (3), driving a pressure shaft (11) by a power device (12) to compress the piece to be tested (15), and measuring a pressure value P by the pressure probe (19) when the compression amount of the piece to be tested (15) is 10mm12Reducing the position of the pressure shaft (11), removing the pressure probe (19), installing the sealing cover plate (9) on the connector (13), adjusting the position of the pressure shaft (11), enabling the sealing cover plate (9) and the test pool (8) to be tightly attached and sealed, opening the air suction valve (21), vacuumizing the test pool (8) by the vacuum pump (2), enabling the interior of the test pool (8) to be in a vacuum state, opening the water inlet valve (22), enabling water in an external water source to enter the test pool (8), enabling the water level in the test pool (8) to be higher than the top of the to-be-tested piece (15) by 3cm, closing the water inlet valve (22), standing for 10min, enabling the to-be-tested piece (15) to be in a water saturation state to simulate the to-be-tested piece (15) to be in a water immersion state, reducing the position of the pressure shaft (11), removing the sealing cover plate (9), and installing the pressure probe (19) on the connector (13), then setting the compression amount of the piece to be tested (15) to be 10mm, driving a pressure shaft (11) by a power device (12) to apply load to the piece to be tested (15), and when the compression amount of the piece to be tested (15) is 10mm, measuring a pressure value P by a pressure probe (19)22(ii) a Then reducing the position of the pressure shaft (11), disconnecting the vacuum pump (2), opening the drain valve (17) and the extraction valve (21) to drain water in the test cell (8), standing for 10min to simulate the state of the test piece (15) after soaking, then compressing the test piece (15) through the pressure shaft (11), and when the compression amount of the test piece (15) is 10mm, measuring by the pressure probe (19) to obtain a pressure value P32；
3c) To a temperature of T1In the mean time, the rate of the decrease of the modulus α in the immersion of the test piece (15) is not limited by the lateral limit12And the modulus reduction rate α of the test piece (15) after immersion22Comprises the following steps:
4c) the test piece (15) is selected and then the temperature in the environmental chamber (1) is adjusted to T2Repeating the steps 2c) and 3c) to obtain a temperature T2In the mean time, the rate of the decrease of the modulus α in the immersion of the test piece (15) is not limited by the lateral limit1′And the modulus reduction rate α of the test piece (15) after immersion2′And the temperature influence coefficient lambda of the piece to be tested (15) is as follows:
4. the test method for evaluating the change in modulus before, after and after flooding an asphalt mixture according to claim 3,
a drain valve (17) is arranged at a water outlet (18) of the test pool (8);
a water inlet valve (22) is arranged at the water inlet (14) of the test pool (8);
an air extraction valve (21) is arranged at the air extraction opening (6) of the test pool (8).
5. Test method for assessing the modulus change before, during and after flooding of an asphalt mixture according to claim 3, characterized in that the rubber base (16) is provided with an annular groove (20), the lower end of the side limiting barrel (7) being embedded in the annular groove (20).
6. Test method for assessing the modulus change before, during and after flooding of an asphalt mixture according to claim 3, characterized in that the bottom of the closing cover (9) is provided with a rubber groove (23) that fits the open-topped wall of the test basin (8).
7. The test method for evaluating the modulus change before, during and after the asphalt mixture is soaked in the water according to claim 3, characterized in that the vacuum pump (2) is communicated with the suction opening (6) on the test pool (8) through a rubber water pipe.
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| CN109470570A (en) * | 2018-11-26 | 2019-03-15 | 山东科技大学 | A kind of water oil isolated form immersion triaxial test case and test method |
| CN112098628B (en) * | 2020-09-16 | 2022-10-25 | 哈尔滨工业大学 | Multifunctional soil tank for lunar soil performance comprehensive test |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101216401A (en) * | 2008-01-09 | 2008-07-09 | 华南理工大学 | Asphalt mixture hydrodynamic pressure scouring test methods and apparatus |
| CN202870088U (en) * | 2012-09-26 | 2013-04-10 | 长安大学 | Device for testing water stability of asphalt mixture |
| CN104515846A (en) * | 2014-12-16 | 2015-04-15 | 重庆交通大学 | Tester for testing water stability of asphalt mixture |
| CN106596285A (en) * | 2016-12-15 | 2017-04-26 | 东南大学 | Experimental device used for evaluation of water stability of bituminous mixture and experimental method |
| CN107063884A (en) * | 2016-12-15 | 2017-08-18 | 东南大学 | A kind of lower experimental provision and test method for evaluating porous asphalt pavement high-temperature behavior of multi- scenarios method effect |
-
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101216401A (en) * | 2008-01-09 | 2008-07-09 | 华南理工大学 | Asphalt mixture hydrodynamic pressure scouring test methods and apparatus |
| CN202870088U (en) * | 2012-09-26 | 2013-04-10 | 长安大学 | Device for testing water stability of asphalt mixture |
| CN104515846A (en) * | 2014-12-16 | 2015-04-15 | 重庆交通大学 | Tester for testing water stability of asphalt mixture |
| CN106596285A (en) * | 2016-12-15 | 2017-04-26 | 东南大学 | Experimental device used for evaluation of water stability of bituminous mixture and experimental method |
| CN107063884A (en) * | 2016-12-15 | 2017-08-18 | 东南大学 | A kind of lower experimental provision and test method for evaluating porous asphalt pavement high-temperature behavior of multi- scenarios method effect |
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