Indoor fatigue test device for asphalt mixture

Abstract

The utility model provides an asphalt mixture indoor fatigue test device which comprises a device shell, wherein a loading table for supporting a test piece and a loading mechanism for impacting the test piece are arranged in the device shell; the device shell is provided with a spraying mechanism for spraying a test piece and a heating mechanism for heating the interior of the device shell. According to the utility model, the spraying mechanism is used for simulating the influence of rain wash on the asphalt mixture fatigue test, and the heating mechanism and the loading mechanism are used for simultaneously considering the effects of high temperature and heavy load axle load under the condition of simulating rainfall, so that the analysis of the three-point bending property fatigue test can be more accurate and comprehensive; the defect of inaccurate sampling and analysis under natural conditions is avoided, and the device is convenient to use and simple to operate.

Description

Technical Field

[0001] The utility model relates to the technical field of asphalt pavement testing, in particular to an indoor fatigue testing device for asphalt mixtures. Background Art

[0002] At present, asphalt concrete pavement is commonly used in my country. The typical disadvantage of asphalt concrete pavement is that it is prone to early fatigue cracking. In recent years, with the development of my country's road freight and logistics industry, heavy-load vehicles such as large freight vehicles have increased rapidly. In particular, affected by global warming, the summer road temperature has increased year by year. Due to the combined effects of high temperature and heavy load, more and more asphalt roads have road fatigue cracking and other diseases shortly after opening to traffic, seriously affecting the service life of asphalt pavement.

[0003] Asphalt pavement is subjected to repeated effects of vehicle loads during service, which causes damage and attenuation of the pavement material strength, resulting in fatigue failure. Existing small-scale fatigue test methods often use three-point beam bending test, midpoint loading beam bending test, cantilever beam test, uniaxial compression test and indirect tension test. There is a big difference between the test process of the above fatigue life test and the environmental conditions of the actual asphalt pavement under vehicle load. Since the asphalt pavement is exposed to the natural environment, in addition to the repeated effects of vehicle loads, it is also affected by temperature loads and atmospheric rainfall. High temperatures in summer will affect the high-temperature stability of the asphalt pavement, leading to the aging of asphalt and aggravating the fatigue failure of the asphalt pavement structure. In addition, under rainfall conditions, the dynamic water pressure caused by the driving load will cause water damage to the asphalt pavement, aggravate the generation of cracks in the asphalt pavement, further shorten the fatigue life of the asphalt pavement, and cause fatigue failure of the asphalt pavement. It can be seen that the coupling effect of high temperature, heavy load and rainfall will aggravate the fatigue failure of the asphalt pavement. However, the existing indoor small-scale fatigue test methods usually do not consider the effects of temperature and rain scouring on asphalt mixture specimens.

[0004] The Chinese invention application with publication date of 2017-07-21 and publication number of CN106969991A discloses an asphalt pavement impact fatigue test device, including an environmental chamber and a main frame, a power box, a guide rod, a pressure head, a drop hammer and a chain located in the environmental chamber; the test piece and the main frame are fixed to the bottom of the environmental chamber, the power box is fixed to the top of the environmental chamber, the guide rod is fixed to the main frame, and the guide rod is distributed in the vertical direction, the test piece is located directly below the guide rod, the pressure head is located directly below the drop hammer, the pressure head is located on the test piece, the drop hammer is hollowly sleeved on the guide rod, the drop hammer is connected to the power box through a chain, and an operation panel is provided on the outer wall of the environmental chamber, wherein the operation panel is connected to the power box. However, the device does not consider the effects of temperature and rain erosion on asphalt mixture specimens. Summary of the invention

[0005] In view of the above-mentioned technical problems, the utility model proposes an indoor fatigue test device for asphalt mixture, which is used to solve the problems in the prior art.

[0006] In order to achieve the above object, the technical solution of the utility model is implemented as follows:

[0007] An indoor fatigue test device for asphalt mixture comprises a device shell, wherein a loading platform for supporting a test piece and a loading mechanism for impacting the test piece are arranged inside the device shell; the device shell is provided with a spraying mechanism for spraying the test piece and a heating mechanism for heating the inside of the device shell.

[0008] Furthermore, the spray mechanism includes a spray head arranged at the top of the device shell and a water inlet pipe connected to the spray head.

[0009] Furthermore, a communicating liquid collecting pool and water outlet pipe are arranged at the bottom of the device shell.

[0010] Furthermore, a slope is provided at the junction of the liquid collecting pool and the inner wall of the device shell.

[0011] Furthermore, the heating mechanism includes a heating wire arranged on the inner wall of the device housing and a control button arranged at the lower part of the device housing, and the heating wire is electrically connected to the control button.

[0012] Furthermore, a blowing mechanism is provided on the side wall of the device shell.

[0013] Furthermore, a box with shutters is provided inside the device shell and is covered on the outside of the blowing mechanism.

[0014] Furthermore, the lower ends of the blades of the shutters are inclined toward the test piece.

[0015] Furthermore, the inner surface of the device shell is painted with waterproof and anti-rust paint.

[0016] Furthermore, the loading mechanism includes a hydraulic rod arranged at the top of the device housing and a loading pressure head connected to the lower end of the hydraulic rod.

[0017] Beneficial effects of the utility model:

[0018] The utility model simulates the influence of rain scouring on the fatigue test of asphalt mixture and takes into account the effects of high temperature and heavy axle load under the condition of simulated rainfall, so that the analysis of the three-point bending performance fatigue test can be more accurate and comprehensive, avoiding the defects of inaccurate sampling and analysis under natural conditions. The utility model is easy to use and simple to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the utility model 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. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 It is a structural schematic diagram of the utility model.

[0021] Figure 2 It is a schematic structural diagram of a box with shutters of the utility model.

[0022] Among them: 1-water inlet pipe, 2-water outlet pipe, 3-sprinkler head, 4-hydraulic rod, 5-loading pressure head, 6-loading platform, 7-liquid collecting tank, 8-box, 9-electric heating wire, 10-test piece, 11-waterproof and anti-rust coating. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0024] like Figure 1 As shown, an indoor fatigue test device for asphalt mixture described in Example 1 of the utility model includes a device shell, and a loading platform 6 for supporting a test piece 10 and a loading mechanism for impacting the test piece 10 are provided in the device shell. The loading mechanism includes a hydraulic rod 4 arranged at the top of the device shell and a loading pressure head 5 connected to the lower end of the hydraulic rod 4, the hydraulic rod 4 is arranged vertically downward, and the loading pressure head 5 is arranged at the lower end of the hydraulic rod 4; the loading platform 6 includes a left support platform and a right support platform, which is convenient for three-point bending performance test, and the pressure of the hydraulic rod 4 can be adjusted to simulate the pressure effect of different levels of axle load on the road surface. The device shell is provided with a spraying mechanism for spraying the test piece 10 and a heating mechanism for heating the inside of the device shell. Under the condition of simulated rainfall, high temperature and heavy axle load are considered at the same time, so that the analysis of the three-point bending performance fatigue test can be more accurate and comprehensive, avoiding the defects of inaccurate sampling and analysis under natural conditions, and is easy to use and simple to operate.

[0025] Further, the spray mechanism includes a spray head 3 arranged at the top of the device housing and a water inlet pipe 1 connected to the spray head 3. The spray head 3 is arranged on both sides of the hydraulic rod 4. The water inlet pipe 1 is arranged outside the device housing.

[0026] Furthermore, a communicating liquid collecting pool 7 and a water outlet pipe 2 are provided at the bottom of the device housing.

[0027] Furthermore, a slope is provided at the junction of the liquid collecting pool 7 and the inner wall of the device housing. In this embodiment, a slope with an inclination angle of 45° is used to better collect rainwater.

[0028] Furthermore, the heating mechanism includes a heating wire 9 arranged on the inner wall of the device housing and a control button arranged at the bottom of the device housing, and the heating wire 9 is electrically connected to the control button. A power line is connected to the outside of the device housing or a power supply is provided at the bottom of the device housing. In this embodiment, the heating wire 9 is installed in the left, right and rear walls of the inner wall of the device, which helps to heat the asphalt mixture sample 10 evenly. The heating wire 9 is powered on and heated to reach a set temperature, which can simulate the influence of different temperatures on the fatigue test of the asphalt mixture specimen 10.

[0029] Embodiment 2 is different from Embodiment 1 in that Figure 1 As shown, a blower mechanism capable of blowing air into the interior is provided on the side wall of the device housing, so as to simulate the effect of wind on the asphalt mixture specimen 10. Moreover, the blower mechanism cooperates with the spray mechanism to simulate rainfall patterns under different wind speed conditions.

[0030] Embodiment 3 is different from Embodiment 2 in that Figure 1 As shown, a box body 8 with shutters is provided inside the housing of the device and is covered on the outside of the blowing mechanism. Figure 2 As shown, the lower ends of the blades of the shutters are inclined toward the test piece 10 so that the wind can blow toward the test piece.

[0031] Embodiment 4 is different from Embodiment 1 in that Figure 1 As shown, the inner surface of the device housing is coated with a waterproof and anti-rust paint 11.

[0032] The specific implementation steps of the utility model are as follows:

[0033] Step 1: firstly, stably place the asphalt mixture specimen 10 on the loading platform 6 to ensure that the asphalt mixture specimen 10 is evenly stressed;

[0034] Step 2: Open the water inlet pipe 1 to allow water to flow into the shower head 3, and start spraying to simulate the rainfall mode; and at the same time, open the blowing mechanism to simulate the rainfall mode under different wind speed conditions;

[0035] Step 3: The heating wire 9 is powered on and heated by the control button of the heating mechanism to reach a set temperature, so as to simulate the influence of different temperatures on the fatigue test of the asphalt mixture specimen 10;

[0036] Step 4: Start the hydraulic rod 4 to move, and drive the loading head 5 to act on the asphalt mixture specimen 10 to perform a three-point bending performance test. The pressure of the hydraulic rod 4 can be adjusted to simulate the pressure of different levels of axle loads on the road surface;

[0037] Step 5: Observe and collect experimental data;

[0038] Step 6: Turn off the power, stop the operation of the sprinkler head 3, the heating wire 9 and the hydraulic rod 4 and take out the asphalt mixture specimen 10 after measuring the data; the simulated rainfall water flows into the liquid collection tank 7 at the bottom of the device shell and is finally discharged through the outlet pipe 2.

[0039] Step 7: Allow the device to cool to room temperature.

[0040] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An indoor fatigue test device for asphalt mixture, characterized in that: The device comprises a housing, wherein a loading platform (6) for supporting a test piece (10) and a loading mechanism for impacting the test piece (10) are provided inside the housing; the device housing is provided with a spraying mechanism for spraying the test piece (10) and a heating mechanism for heating the interior of the device housing.

2. The asphalt mixture indoor fatigue test device according to claim 1, characterized in that: The spray mechanism comprises a spray head (3) arranged at the top of the device housing and a water inlet pipe (1) connected to the spray head (3).

3. The asphalt mixture indoor fatigue test device according to claim 1 or 2, characterized in that: A communicating liquid collecting pool (7) and a water outlet pipe (2) are provided at the bottom of the device housing.

4. The asphalt mixture indoor fatigue test device according to claim 3, characterized in that: An inclined surface is provided at the junction of the liquid collecting pool (7) and the inner wall of the device housing.

5. The asphalt mixture indoor fatigue test device according to claim 1, 2 or 4, characterized in that: The heating mechanism comprises a heating wire (9) arranged on the inner wall of the device housing and a control button arranged at the lower part of the device housing, and the heating wire (9) is electrically connected to the control button.

6. The asphalt mixture indoor fatigue test device according to claim 1, 2 or 4, characterized in that: A blowing mechanism is arranged on the side wall of the device shell.

7. The asphalt mixture indoor fatigue test device according to claim 6, characterized in that: A box body (8) with shutters is arranged inside the housing of the device and covers the outside of the air blowing mechanism.

8. The asphalt mixture indoor fatigue test device according to claim 7, characterized in that: The lower ends of the blades of the shutters are all inclined toward the test piece (10).

9. The asphalt mixture indoor fatigue test device according to claim 1 or 2 or 4 or 7 or 8, characterized in that: The inner surface of the device housing is coated with a waterproof and rust-proof paint (11).

10. The asphalt mixture indoor fatigue test device according to claim 1 or 2 or 4 or 7 or 8, characterized in that: The loading mechanism comprises a hydraulic rod (4) arranged at the top of the device housing and a loading pressure head (5) connected to the lower end of the hydraulic rod (4).

Images