JP2001059805A - Load moving test apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform highly reliable evaluation by precisely reproducing the generation state of damage with high faithfulness corresponding to various conditions. SOLUTION: In a load moving test apparatus 1, a test piece 2 is also moved along a running direction along with the rotational driving of a test wheel 51, and, by the combination of the motions of both of them, for example, the relative speed of the test wheel 51 to the test piece 2 is set to a wide range. The test wheel 51 is controlled so as not only to be angularly displaced on a horizontal surface with respect to the running direction L, but also to be moved along a lateral direction by a traverse mechanism 55 along with the rotational driving of the test wheel 51 to faithfully reproduce the generation state of deformation or abrasion, for example, in the curved part of a road.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a load transfer test device for promoting abrasion of an asphalt mixture used in asphalt pavement and performing a quality test of the asphalt mixture.

[0002]

2. Description of the Related Art As a load transfer test device for performing a quality test of an asphalt mixture used in asphalt pavement, for example, an asphalt mixture surface is evaluated by evaluating the consolidation and flow resistance of the asphalt mixture. There is a wheel tracking tester for performing an anticipated evaluation of a rutting phenomenon or the like that occurs in a vehicle.

As shown in FIG. 11, a wheel tracking tester 101 has a test wheel 103 that performs a horizontal reciprocating motion on a test piece 102.

When the test wheel 103 reciprocates a predetermined number of times on the specimen 102, the surface of the specimen 102 is deformed. This reciprocating motion is performed under predetermined conditions where the temperature and the like are constant, and the above-described deformation state is measured.
2 is evaluated.

[0005] Recently, for the purpose of ensuring safety and recharging groundwater, permeable pavements and drainage pavements that allow rainwater to pass through voids in pavements using a porous material have appeared.

[0006]

However, at present, no evaluation method has been established for the water-permeable pavement or the drainage pavement. About
It does not cover permeable pavement or drainage pavement.

[0007] Therefore, it is difficult for the conventional testing machine to accurately and accurately reproduce the state of occurrence of breakage such as deformation or wear under various assumed conditions, so that a highly reliable evaluation is required. There is a problem that it cannot be performed.

Accordingly, the present invention provides a load transfer test apparatus that can accurately reproduce the state of occurrence of breakage with high fidelity corresponding to various conditions and can be used for highly reliable evaluation. The purpose is to:

[0009]

In order to solve the above-mentioned problems, an invention according to claim 1 is a load transfer test apparatus for applying a moving load to a specimen on a pavement road surface and performing a quality test of the specimen. And a mounting table for mounting the specimen, and a traveling loading mechanism including a test wheel that applies a moving load to the specimen, wherein the traveling loading mechanism is a wheel driving unit that rotationally drives the test wheel. And an angular displacement mechanism for angularly displacing the test wheel on a horizontal plane with respect to a traveling direction.

[0010] In order to solve the above-mentioned problems, the invention according to claim 2 is a load transfer test apparatus according to claim 1,
The mounting table can be moved along the traveling direction by a mounting table moving mechanism.

According to a third aspect of the present invention, there is provided a load transfer test apparatus according to the first or second aspect, wherein the traveling loading mechanism moves the test wheel in the traveling direction. A traverse mechanism that moves along a horizontal direction orthogonal to a horizontal plane, and a wheel lifting mechanism that moves the test wheel up and down are provided.

According to a fourth aspect of the present invention, there is provided a load-moving test apparatus according to the second or third aspect, wherein an arbitrary point on a peripheral surface of the rotating test wheel is provided. The wheel drive means and the table moving mechanism are interlockingly controlled so that the speed at the time of touching the specimen and the moving speed of the specimen moving along the traveling direction maintain a predetermined ratio. Features.

According to a fifth aspect of the present invention, there is provided a load transfer test apparatus according to any one of the first to fourth aspects, wherein the wheel driving means includes the test wheel. , And the motor is controlled so that the torque of the motor is maintained at a predetermined constant value.

According to a sixth aspect of the present invention, there is provided a load transfer test apparatus according to any one of the third to fifth aspects, wherein the test wheel is driven by the angular displacement mechanism. Is controlled by the traverse mechanism so as to move the test wheel along the lateral direction while displacing the test wheel by a predetermined angle and maintaining the predetermined angle.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings.

Embodiment 1 FIG. 1 is a front view showing a configuration of an accelerated wear durability test apparatus according to Embodiment 1 of the present invention, FIG. 2 is a plan view showing a configuration of the accelerated wear durability test apparatus, and FIG.
Is a side view showing a test wheel and a wheel drive unit constituting the accelerated wear durability test apparatus, FIG. 4 is a front view showing the test wheel and the wheel drive unit, and FIG. 5 is a cross section taken along line BB in FIG. Figure,
FIG. 6 is an exploded perspective view schematically showing the configuration of the wheel angle adjustment unit, FIG. 7 is a block diagram showing the electrical configuration of the accelerated wear durability test apparatus, and FIG. 8 shows a method of angular displacement in the wheel angle adjustment unit. FIG. 9 is an explanatory diagram for explaining the operation of the accelerated wear test device, and FIG. 10 is an explanatory diagram for explaining a method in which the speeds of the test wheel and the specimen are interlocked. is there.

FIG. 1 shows a state in which the wall of the water tank on the front side on the mounting table is omitted.

As shown in FIGS. 1 and 2, accelerated wear durability test apparatus (load transfer test apparatus) according to the first embodiment.
Reference numeral 1 denotes a test device used to apply a moving load to a specimen 2 made of an asphalt mixture to promote abrasion and reproduce a model of a broken state to perform a quality test of the specimen 2, for example, a groove. A frame-shaped structure 3 that is assembled using a shaped steel, an angle iron, a steel plate, or the like, and that mounts and supports various mechanisms described below, a mounting table 4 on which the specimen 2 is mounted, and A traveling loading device (traveling loading mechanism) 5 for applying a moving load, a loading table moving mechanism 6 for horizontally reciprocating the loading table 4, and a water immersion device 7 for accommodating the specimen 2 in water. And an operation control unit 8 for operating the accelerated wear durability test apparatus 1 and controlling each component.

Specimen 2 is an asphalt mixture placed in a box-shaped form 9 made of metal, and is 30 cm square or 50 cm square.
It has dimensions of cm square and a thickness of about 5 cm.

The traveling loading device 5 includes a test wheel 51 that horizontally reciprocates on the specimen 2, a wheel driving unit (wheel driving unit) 52 that rotationally drives the test wheel 51, and a test wheel 51 and a wheel driving unit 52. Two directions perpendicular to each other on a horizontal plane, which are suspended from the ceiling portion 31 of the frame-shaped structure 3, that is, the running direction (left-right direction shown in FIGS. 1 and 2) L and the horizontal direction perpendicular to the running direction (up and down shown in FIG. Traveling support 53 that supports the frame-like structure 3 so as to be able to reciprocate along the direction T).
A wheel angle adjuster 54 that holds the test wheel 51 at a maximum angle of 30 ° clockwise or counterclockwise in the horizontal plane with respect to the running direction L, and holds the running support 53, that is, the test wheel 51. And a traverse mechanism 55 for moving in the direction T.

Here, the test wheel 51 has an outer diameter of 2
A solid tire having 0 cm, a width of 5 cm, a rubber thickness of 1.5 cm, and a rubber hardness of 80 ± 3 at 20 ° C. and 78 ± 2 at 60 ° C. is used.

As shown in FIG. 1 to FIG.
2 includes a drive motor (electric motor) 521 that rotates forward and backward under the control of the operation control unit 8, and a belt 522 that transmits the rotational motion of the drive motor 521 to the test wheels 51.

The traveling support 53 is provided with guide rails 555, 5 arranged on the ceiling 31 along the lateral direction T.
A movable base 531 on both sides of which are reciprocally movable in the lateral direction T on the base 55, and a movable base 531 mounted on the guide rails 531 a and 531 a of the movable base 531 so as to be capable of reciprocating in the traveling direction L. Moving mount 532 and moving mount 5
A mounting mechanism 534 including a mounting shaft 533 vertically attached to a central portion of the P. 32 and a test wheel 51 and a wheel driving portion 52 at a lower end thereof, and a drive motor 534a for vertically moving the test wheels 51 in the vertical direction.
And a load adjusting mechanism 535 for adjusting the load on the specimen 2 with a screw jack.

The reciprocating speed of the test wheel 51 by the drive motor 521 (wheel self-running speed) is 300 mm at the maximum.
/ S.

The load adjusting mechanism 535 has a load of 7 in a standard wheel tracking test.
It is adjusted so that a load in the range of ± 20 kg is applied to 0 kg.

As shown in FIGS. 3 to 6, a wheel angle adjusting section (angular displacement mechanism) 54 is fixed to the lower end of the mounting shaft 533 via mounting members 534, 535, and a predetermined-diameter bolt is inserted through the center. A fixed mounting plate member 541 having a hole 541a formed therein, a mounting plate member 542 fixed to the test wheel 51 side, and a driving motor 52 connected to the mounting plate member 542 using bolts inserted through the bolt insertion holes 541a.
A mounting plate member 543 fixed to the first side;
2 and a mounting member 544 fixed to the fixed mounting plate member 541.

At both sides of the mounting plate member 542, mounting holes 542b and 542c for fixing the mounting member 544 doubly and concentrically with respect to the rotation axis are provided at positions corresponding to the wheel angles.

The mounting holes 542b and 542c are arranged at an angular interval of 5 ° with respect to the rotation axis, and rotate the test wheel 51 and the wheel driving unit 52 clockwise and counterclockwise on a horizontal plane with respect to the running direction L. It is designed to be angularly displaced by 5 ° up to a maximum of 30 °.

Mounting holes 542 corresponding to predetermined wheel angles
b or mounting hole 542c and mounting hole 5 of mounting member 544
44a, and the bolt is inserted to fix the mounting plate member 542. Further, the mounting plate member 542 and the mounting plate member 543 are aligned with the mounting hole 542a and the mounting hole 543a, and the bolt insertion hole 541a is aligned. The test wheel 51 and the wheel driving unit 52 are fixed at a predetermined wheel angle by inserting and fixing the bolts inside.

The mounting member 544 has a through hole 544b.
A bolt is inserted from below, and the bolt is screwed into a female screw portion (not shown) provided on the fixed mounting plate member 541 to be fixed to the fixed mounting plate member 541.

The traverse mechanism 55 is arranged along the transverse direction T on the ceiling 31 with the drive motor 551 rotating forward and backward. The traverse mechanism 55 is rotated by the rotation of the drive motor 551 transmitted through the chain 552 and the male screw is screwed. It has a screw screw 553 provided and a nut portion 554 fixed to the moving base 531 and screwed with the screw screw 553.

Here, the reciprocating speed (wheel traverse speed) of the test wheel 51 in the lateral direction T by the drive motor 551 is set to 30 to 100 mm / s.

The mounting table moving mechanism 6 is arranged along the running direction L on the floor 32 and a driving motor 61 that rotates forward and backward. The rotating motion of the driving motor 61 is transmitted via a belt 62 to rotate, and the mounting table moving mechanism 6 rotates. Screw 6 with thread
3 and a nut portion which is fixed to the mounting table 4 mounted on the guide rail 65 arranged on the floor 32 along the running direction L so as to be reciprocally movable along the running direction L and screwed with the screw screw 63. 64.

Here, the reciprocating speed (test object speed) of the mounting table 4, that is, the test object 2 along the running direction L by the drive motor 61 is set to 300 mm / s at the maximum.

The water immersion device 7 includes a water tank 71 formed on the mounting table 4 and a circulation pump 72 for circulating water in the water tank 71.
And a heater 73 having a capacity of, for example, 3 kW for heating water in the water tank 71 to a predetermined water temperature (see FIG. 7).

The operation control section 8 has a control panel 8A and a relay panel (not shown) attached to the frame-shaped structure 3 side.
On the panel surface of the control panel 8A, the respective mechanisms are started or stopped, and the ratio of the rotation speed of the drive motor 61 to the rotation speed of the drive motor 61 (interlocking ratio) of the self-running speed of the wheels, the wheel traverse speed, the test object speed, and the rotation speed of the drive motor 521. , Number of tests (number of round trips),
An operation setting section 81 for setting the torque and the like of the drive motor 521 and a display section 82 including instruments for indicating each speed and the current value of the drive motor 521 are provided.

Here, the above-mentioned interlocking ratio is 100
It can be set from% to 30%.

Next, the electrical configuration of this accelerated wear durability test apparatus will be described.

As shown in FIG. 7, the accelerated wear durability test apparatus 1 includes limit switches LS11 to LS11 for detecting a limit position of movement of the movable mounting table 532, the mounting table 4, and the like.
S14, LS21, LS22, LS31 to LS34, L
S41 to LS44, and center position detectors PD1 and PD for detecting the center position of the test wheel 51 along the running direction L and the lateral direction T and the center position of the specimen 2, respectively.
2, PD3, a temperature sensor TD for detecting a water temperature in the water tank 71, and drive motors 521, 551, 534a,
61, a circulation pump 72, a heater 73, and the operation control unit 8.

Of the above limit switches, the limit switches LS11 to LS14 are arranged corresponding to the limit positions of the horizontal reciprocating movement of the movable mount 532 along the running direction L, and the limit switches LS21 and LS22 are connected to the test wheels 51. And the limit switches LS31 to LS34 are arranged corresponding to the vertical movement limit positions of the wheel drive unit 52.
Are arranged corresponding to the limit position of the horizontal reciprocating movement of the movable mounting base 532 along the lateral direction T, and the limit switch L
S <b> 41 to LS <b> 44 are arranged corresponding to the limit positions of the horizontal reciprocation along the traveling direction L of the mounting table 4.

Here, the limit switches LS11, LS
12, LS31, LS32, LS41 and LS42 are 30
The limit switches LS13 and LS
14, LS33, LS34, LS43 and LS44 are 50
The specimens 2 are arranged at positions corresponding to the cm 2 specimens.

The operation control section 8 includes an operation setting section 81
And a display unit 82, and a main control unit 83 that controls various components according to a predetermined control program and performs various arithmetic processes.
And

The main control unit 83 includes, for example, the operation setting unit 8 in advance.
The drive motor 521 and the like are controlled based on each speed, interlocking ratio, torque, and the like set in Step 1.

Next, the operation will be described.

First, the frame-like structure main body to which each mechanism is attached is fixed to the floor with the caster 3b floated by the fixing jack 3a.

Then, the specimen 2 of, for example, 30 cm square prepared in advance is placed on the mounting table 3 while being held by the box-shaped form 9.

Next, in order to adjust the wheel angle to a desired angle, a mounting hole 542b or a mounting hole 542c corresponding to a predetermined wheel angle and a mounting hole 544a of the mounting member 544 are provided.
Are aligned, and bolts are inserted through the mounting plate member 542.
Are fixed, and the mounting plate member 542 and the mounting plate member 5 are further fixed.
43, the mounting holes 542a and the mounting holes 543a are aligned, and bolts are inserted and fixed in the bolt insertion holes 541a. Thus, the test wheel 51 and the wheel driving unit 52 are fixed at a predetermined wheel angle.

Here, as shown in FIG.
The center axis is rotated by 30 ° clockwise as indicated by X1 in the figure and 30 ° counterclockwise as indicated by X2 in the figure with respect to the position indicated by X0 in the figure orthogonal to the running direction L. To be displaced between the two positions.

Next, after adjusting the load, the operation setting section 81 adjusts the test object speed, the wheel self-running speed, the wheel traverse speed, the interlocking ratio, the drive motor torque, the number of tests, and the like so as to meet predetermined conditions. Configure and start.

For example, in the case where only the test wheel 51 is simply horizontally reciprocated, the wheel self-running speed, the drive motor torque,
After setting the number of tests, the test wheel 51 and the specimen 2
To the center position to start reciprocating motion.

The test wheel 51 is connected to the limit switch LS1
As shown in FIG. 9, by detecting the limit position by the LS 12, as shown in FIG. 9, the distance between one edge position of the test object 2 shown in the figure 51A and the other edge position shown in the figure 51B is drawn. Reciprocate a predetermined number of times.

As a result, damage such as predetermined wear and deformation occurs on the surface of the specimen 2.

When both the test wheel 51 and the specimen 2 are caused to reciprocate horizontally in the running direction L, for example, the apparatus is started by setting an interlocking ratio.

With this initial setting, the degree of relative movement between the test wheel 51 and the specimen 2 is selected in a wide range.

Here, when the interlocking ratio is 100%, for example, as shown in FIG. 10, the speed Va when the arbitrary point P on the peripheral surface of the test wheel 51 touches the specimen 2 at the time of contact with the specimen 2 is measured. And the size and direction are the same as the speed Vb.

Also, for example, by changing the magnitude of the wheel self-running speed and the specimen speed and appropriately setting the value of the torque of the drive motor 521, the occurrence of slip when the test wheel 51 rotates can be reduced. It is also possible to control the presence or absence.

For examining an object applied to a curved portion of a road, for example, the wheel angle adjustment unit 54 adjusts the wheel angle to a predetermined wheel angle in advance, sets the wheel traverse speed at the same time, By repeatedly moving while moving in the lateral direction T, the state of damage when applied to the curved portion is reproduced.

When the test is to be performed in a water immersion state,
After the water temperature is set to a predetermined value, a test is performed by combining the above-mentioned reciprocating motion in a state where the test sample 2 is immersed in the water tank 71 by operating the circulation pump 72.

As described above, according to the first embodiment, the specimen 2 can be moved along the traveling direction L together with the rotation of the test wheel 51. The relative speed of the test wheel 51 to the specimen 2 can be set in a wide range.

In particular, to keep the interlocking ratio constant,
By interlocking the drive motor 521 and the drive motor 61, the relative speed of the test wheel 51 with respect to the specimen 2 can be reliably and accurately adjusted, and precise speed setting can be performed in a wide range.

Therefore, for example, a very low speed state can be easily and stably realized, and the damage situation at an intersection, a parking lot, or the like can be easily and faithfully reproduced.

Further, by controlling the torque of the drive motor 521 so as to maintain a substantially constant value, a desired speed can be reliably obtained, and by appropriately setting the value of the torque, for example, the occurrence of slip may occur. The wear condition at the time can be faithfully reproduced.

Further, since the test wheel 51 can be angularly displaced on the horizontal plane with respect to the traveling direction L together with the rotation drive of the test wheel 51, the material applied to the place where the steering wheel is likely to be turned is deformed. It can be used to faithfully reproduce the state of occurrence of breakage such as wear and abrasion, and perform highly reliable evaluation.

In particular, by controlling the test wheels 51 to move in the lateral direction T by the traverse mechanism 55, it is possible to faithfully reproduce, for example, the occurrence of deformation, wear, and the like in the curved portion of the road.

Although the embodiment of the present invention has been described in detail, the specific configuration is not limited to this embodiment.

For example, in the above-described embodiment, a case has been described in which a specimen prepared in advance is used, but a specimen cut directly from the site may be used.

[0067]

As described above, according to the first aspect of the present invention, the steering wheel can be turned because the test wheel can be angularly displaced on the horizontal plane with respect to the traveling direction together with the rotational driving of the test wheel. For a material applied to a location having a high possibility, it is possible to faithfully reproduce, for example, the state of occurrence of damage such as deformation or abrasion at a curved portion of a road, and to use the material for highly reliable evaluation.

According to the second aspect of the present invention, since the specimen can be moved together with the rotational driving of the test wheel, the relative speed of the test wheel with respect to the specimen can be varied over a wide range depending on the combination of the two movements. It is possible to accurately reproduce the occurrence of damage such as deformation and wear with high fidelity corresponding to various conditions, which can be used for highly reliable evaluation.

According to the third aspect of the present invention, the test wheels are moved in the lateral direction by the traverse mechanism, so that the material applied to the portion where the lateral displacement is likely to occur due to centrifugal force or the like is deformed or worn. This can be used to faithfully reproduce the state of occurrence of breakage such as damage and perform highly reliable evaluation.

According to the fourth aspect of the present invention, the wheel driving means and the mounting table moving mechanism are linked so that the speed of the test wheel and the moving speed of the specimen maintain a predetermined ratio.
The relative speed of the test wheel with respect to the specimen can be reliably and accurately adjusted, and a precise speed can be set in a wide range. For example, a very low speed state can be easily and stably realized.

According to the fifth aspect of the present invention, the torque of the electric motor of the wheel driving means is controlled so as to maintain a substantially constant value, so that a desired speed can be obtained with certainty.
For example, by appropriately setting the value of the torque, it is possible to faithfully reproduce, for example, a wear state when a slip occurs.

According to the sixth aspect of the present invention, the test wheels are controlled to be moved in the lateral direction by the traverse mechanism while the test wheels are displaced by the predetermined angle by the angular displacement mechanism. For example, it is possible to faithfully reproduce the state of occurrence of deformation, wear, and the like in a curved portion of a road.

[Brief description of the drawings]

FIG. 1 is a front view showing a configuration of an accelerated wear durability test apparatus according to Embodiment 1 of the present invention.

FIG. 2 is a plan view showing a configuration of the accelerated wear durability test apparatus.

FIG. 3 is a side view showing a test wheel and a wheel drive unit constituting the accelerated wear durability test apparatus.

FIG. 4 is a front view showing the test wheel and a wheel drive unit.

FIG. 5 is a sectional view taken along line BB of FIG. 4;

FIG. 6 is an exploded perspective view schematically illustrating a configuration of a wheel angle adjustment unit.

FIG. 7 is a block diagram showing an electrical configuration of the accelerated wear durability test apparatus.

FIG. 8 is an explanatory diagram for explaining a method of angular displacement in the wheel angle adjustment unit.

FIG. 9 is an explanatory diagram for explaining an operation of the accelerated wear test device.

FIG. 10 is an explanatory diagram for explaining a method in which the speeds of the test wheel and the specimen are linked.

FIG. 11 is an explanatory diagram for explaining a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Load movement test apparatus 2 Specimen 4 Mounting table 5 Travel loading device (travel loading mechanism) 51 Test wheel 52 Wheel drive part (wheel drive means) 521 Drive motor (electric motor) 534 Wheel lifting mechanism 54 Wheel angle adjustment part (Angle displacement) Mechanism) 55 traverse mechanism 6 mounting table moving mechanism

Claims (6)

[Claims] 1. A load transfer test apparatus for applying a moving load to a specimen on a pavement road surface to perform a quality test of the specimen, comprising: a mounting table on which the specimen is mounted; A traveling loading mechanism including a test wheel for applying a load, the traveling loading mechanism comprising: a wheel driving unit configured to rotationally drive the test wheel; and an angular displacement mechanism configured to angularly displace the test wheel on a horizontal plane with respect to a traveling direction. And a load transfer test device. 2. The load transfer test device according to claim 1, wherein the mounting table is movable along the traveling direction by a mounting table moving mechanism. 3. The traveling loading mechanism includes a traverse mechanism that moves the test wheel along a horizontal direction orthogonal to the traveling direction on a horizontal plane, and a wheel lifting mechanism that moves the test wheel up and down. 2. The method according to claim 1, wherein
Or the load transfer test device according to 2. 4. A predetermined ratio is maintained between a speed at which an arbitrary point on the peripheral surface of the rotating test wheel is in contact with the test object and a moving speed at which the test object moves along the traveling direction. The load transfer test device according to claim 2 or 3, wherein the wheel drive means and the mounting table moving mechanism are interlocked and controlled. 5. The vehicle according to claim 1, wherein the wheel driving means includes an electric motor for driving the test wheel to rotate, and the torque of the electric motor is controlled so as to maintain a predetermined constant value. The load transfer test device according to any one of the above items. 6. The traverse mechanism is controlled to move the test wheels along the lateral direction while the test wheels are displaced by a predetermined angle by the angular displacement mechanism and the predetermined angle is maintained. The load transfer test device according to any one of claims 3 to 5, wherein: