Pavement testing machine

Abstract

The objective is to provide a pavement testing machine that can reflect the actual condition of paved roads. [Solution] The pavement testing machine 1 comprises a test formwork 3, a test specimen 5 formed on a foundation structure 161 within the test formwork 3, and a tire 27 that rolls on the test specimen 5. The test specimen 5 is made of pavement material, and the foundation structure 161 includes a deflection-allowing mechanism 101 that allows deflection of the test specimen 5.

Description

Technical Field

[0001] The present invention relates to a pavement testing machine.

Background Art

[0002] Conventionally, there is a technique for clarifying the relationship between the occurrence status of fatigue cracks in a road in use and the fatigue fracture characteristics of an asphalt mixture, and verifying the occurrence time of fatigue cracks (see, for example, Non-Patent Document 1). Also conventionally, there is a pavement testing machine which is an indoor type pavement testing machine, prepares a specimen of an asphalt mixture, places the specimen on a test mold, and actually runs a tire on the specimen to conduct a fatigue crack test.

Prior Art Documents

Non-Patent Documents

[0003]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the state of an actual pavement road is affected by the natural environment, that is, the temperature environment, water immersion, deflection of the road surface, etc., and there is a possibility that the test by the above-described conventional pavement testing machine cannot reflect these actual road usage conditions. An object of the present invention is to provide a pavement testing machine that solves the problems of the above-described conventional technology and can reflect the state of an actual pavement road.

Means for Solving the Problems

[0005] A pavement testing machine according to an aspect of the present invention includes a test mold, a specimen formed on a base structure within the test mold, and a tire that rolls on the specimen. The specimen is formed of a pavement material, and the base structure includes a deflection allowance mechanism that allows deflection of the specimen. The deflection-allowing mechanism includes an air tube that compresses when the tire is placed on the test specimen and returns the test specimen to its original position after the tire has passed over it. Furthermore, a pavement testing machine according to another aspect of the present invention comprises a test formwork, a test specimen formed by compacting pavement material on a foundation structure within the test formwork, and a tire that rolls on the test specimen, wherein the foundation structure comprises a plurality of square pipes that support the test specimen, a plurality of wedge members that are positioned to fill the spaces between the square pipes and are removable, and a deflection-allowing mechanism that allows deflection of the test specimen, wherein the deflection-allowing mechanism is formed by the gap created when the wedge members are pulled out from between the foundation structure and the test specimen after the test specimen has been formed. [Effects of the Invention]

[0006] In a pavement testing machine according to one aspect of the present invention, the test specimen formed from pavement material is deflected by a deflection-allowing mechanism, thus reflecting the actual condition of the paved road. [Brief explanation of the drawing]

[0007] [Figure 1] This is a diagram showing a pavement testing machine. [Figure 2] This is a cross-sectional view of the test formwork. [Figure 3] This is a top-down plan view of the test formwork. [Figure 4] This is a side view of the wedge member. [Figure 5] This is a side view of a test formwork equipped with a different type of deflection-allowing mechanism. [Figure 6] This is a top-down plan view of a test formwork equipped with a different type of deflection-allowing mechanism. [Figure 7] This is a cross-sectional view AA in Figure 6. [Figure 8] Figure 6 is a cross-sectional view of BB. [Figure 9] Figure 6 is a cross-sectional view of CC. [Figure 10] Figure 2 shows enlarged views of the regions indicated by α, β, and γ. [Modes for carrying out the invention]

[0008] (Embodiment 1) Embodiment 1 of the present invention will be described below with reference to the drawings. [1. Structure] [1-1. Basic Configuration of a Pavement Testing Machine] Figure 1 shows the pavement testing machine 1. The mounting test machine 1 includes a rotary support shaft 19 that extends vertically and is rotatably fixed to the ceiling 15 and the underside of the floor 17. The rotary support shaft 19 can be rotated about the vertical axis by a drive motor 21 under the floor. A drive gear 19A is formed at the lower end of the rotary support shaft 19, and the drive motor 21 is connected to the drive gear 19A via a gear 23. Four frames 25 that extend crosswise in a horizontal plane are fixed to the rotary support shaft 19. Suspension mechanisms 29 are provided at the radially outer ends of the frames 25 respectively. Each suspension mechanism 29 includes a buffer member 31, and a tire 27 is rotatably connected to the buffer member 31. There are a total of four tires 27.

[0009] A groove portion 33 is formed on the floor 17 opposite to the tire 27, and a support frame 35 is arranged in the groove portion 33. The support frame 35 includes a polygonal annular inner frame 35A and a similarly polygonal annular outer frame 35B in a plan view. A plurality of test molds 3 are arranged side by side in the circumferential direction in a plan view on the inner frame 35A and the outer frame 35B. Each test mold 3 is fastened to the support frame 35 with a fixture (not shown).

[0010] Referring to FIG. 1, when the rotary support shaft 19 is rotated, the four frames 25 rotate in the same direction, and the tires 27 rotate integrally with the frames 25. The tires 27 roll on top of a plurality of test molds 3 arranged side by side in a plan view. The tires 27 rotate at a high speed of about 100 km / h, for example, and the rotation and rolling speeds of the tires 27 are arbitrarily adjusted according to the test situation.

[0011] [1-2. Test mold] [1-2-1. Basic structure] FIG. 2 is a cross-sectional view of the test mold 3, and FIG. 3 is a plan view of the test mold 3 seen from above. The test mold 3 is box-shaped with an open top and sides and a bottom. As shown in Fig. 3, the test mold 3 is substantially trapezoidal in plan view. It is trapezoidal with a narrow width at the part that rests on the inner frame 35A and a wide width at the part that rests on the outer frame 35B. The test mold 3 is fastened to the support frame 35 with a fixture (not shown). The upper side of the test mold 3 in Fig. 3 corresponds to the inner wall portion 49B on the radially inner side of the paving tester 1, and the lower side in Fig. 3 corresponds to the outer wall portion 49A on the radially outer side of the paving tester 1. The outer wall portion 49A and the inner wall portion 49B are made of metal.

[0012] As shown in Fig. 2, the test mold 3 is a box shape with a bottom and includes a bottom plate 57. The bottom plate 57 is made of metal. After bulging downward, the bottom plate 57 connects the lower end of the inner wall portion 49B and the lower end of the outer wall portion 49A. Concrete is placed on the bottom plate 57 to form a base 59. The upper surface of the base 59 is located at the middle part of the height of the test mold 3. A foundation structure 61 extending in the horizontal direction is arranged on the concrete base 59. A heating device 71 is arranged on the foundation structure 61, and a specimen 5 is formed on the heating device 71. The specimen 5 includes a granular roadbed layer 7, an asphalt stabilizing treatment layer 9, a base layer 11, and a surface layer 13. The specimen 5 is compacted by rolling from above the surface layer 13 on the foundation structure 61.

[0013] [1-2-2. Foundation Structure] The foundation structure 61 includes three corner pipes 63. Of the three corner pipes 63, the inner one is arranged along the inner surface of the inner wall portion 49B, the outer one is arranged along the inner surface of the outer wall portion 49A, and the remaining one is arranged at the middle part between the inner wall portion 49B and the outer wall portion 49A. A plurality of wedge members 65 are provided between the three corner pipes 63. The wedge members 65 are arranged in parallel so as to fill the space between the corner pipes 63. As shown in Figure 4, the wedge member 65 comprises a first wedge member 65A and a second wedge member 65B that overlaps the first wedge member 65A. The first wedge member 65A and the second wedge member 65B each have holes 65C at their ends, and the first wedge member 65A can be inserted into or removed by fixing an extraction tool (not shown) to these holes 65C and pulling.

[0014] After the specimen 5 is formed on the foundation structure 61, when the first wedge member 65A is withdrawn, the second wedge member 65B falls down (not shown in the illustration), creating a space above the second wedge member 65B. If several first wedge members 65A are withdrawn, the corresponding second wedge members 65B fall down, creating a space above the fallen second wedge members 65B. This creates a gap between the foundation structure 61 and the specimen 5. These gaps correspond to an example of a deflection-allowing mechanism that allows for deflection of the specimen 5. Furthermore, both the first wedge member 65A and the overlapping second wedge member 65B may be pulled out to form a space.

[0015] [1-2-3. Alternative Forms of Foundation Structures] Figure 5 is a side view of the test formwork 3 equipped with a deflection tolerance mechanism 101. Figure 6 is a top view of the same test formwork 3. Another configuration of the foundation structure 161 includes a deflection-allowing mechanism 101 to allow for deflection of the test specimen 5. The configuration other than the foundation structure 161 is substantially the same as that in Figure 2, and a heating device 71 is placed on top of the foundation structure 161.

[0016] As shown in Figure 5, the foundation structure 161 is divided into an outer foundation structure 161A on the radially outer side of the test formwork 3 and an inner foundation structure 161B on the radially inner side. A base steel plate 161C is attached to the entire lower surface of the foundation structure 161.

[0017] The outer foundation structure 161A comprises joists 105 and outer steel plates 107 attached to the upper surface of the joists 105. Multiple joists 105 are arranged on the base steel plate 161C at intervals in the radial direction of the test formwork 3 and are fixed to the concrete base 59.

[0018] The inner foundation structure 161B comprises a pair of joists 105, square pipes 63 laid between the pair of joists 105, a plurality of air tubes 109 placed on the upper surface of the square pipes 63, and an inner steel plate 111 attached over the plurality of air tubes 109, all on a base steel plate 161C. The inner steel plate 111 is fixed to the pair of joists 105. The air tubes 109 are routed in the gap between the inner steel plate 111 and the square pipes 63. The inner foundation structure 161B is equipped with a jack mechanism 127 in the center, parallel to the square pipes 63.

[0019] As shown in Figure 6, the jack mechanism 127 includes four jack sections 129 and a lifting plate 131 that can be raised and lowered by the four jack sections 129. The jack section 129 is connected to a hydraulic hose 133 that runs along the underside of the outer steel plate 107. The hydraulic hose 133 is routed through a hole formed in the joist 105 below the outer steel plate 107. The hydraulic hose 133 is connected to a hydraulic pump 135 located outside the test formwork 3. The inner foundation structure 161B is provided with a pair of air pipes 113 on both sides of the inner foundation structure 161B for supplying air to a plurality of air tubes 109. The pair of air pipes 113 are fixed to the side edges of the base iron plate 161C. Note that the air pipes 113 are not shown in Figure 5.

[0020] Of the pair of air tubes 113, one air tube 113A is connected to a plurality of first air tubes 109A, and the other air tube 113B is connected to a plurality of second air tubes 109B. In a plan view, the first air tubes 109A and the second air tubes 109B are arranged alternately, one by one, and parallel to each other. Air tube 109, first air tube 109A, and second air tube 109B are examples of the "flexure tolerance mechanism 101".

[0021] Figure 7 is a cross-sectional view AA of Figure 6, showing the connection point between the air pipe 113 and the intake hose 115 connected to the air pipe 113. As shown in Figure 7, each pair of air pipes 113 is equipped with a coupler 117 projecting upward at its radially outer end. An intake hose 115 extending from a compressor 119 is detachably attached to the coupler 117.

[0022] Figure 8 is a cross-sectional view of BB in Figure 6. The air pipe 113 and the first air tube 109A are connected via a hose nipple 121. The hose nipple 121 is attached to the air pipe 113. A buffer plate 114 is placed between the air pipe 113 and the inner iron plate 111. The buffer plate 114 may be made of metal, wood, or resin. The hose nipple 121 and the first air tube 109A are tightened together by a hose clamp 123. Although not shown in the diagram, the second air tube 109B and the other air pipe 113 have a similar configuration. In this way, multiple air tubes 109 are connected to the air pipe 113 via multiple hose nipples 121.

[0023] Figure 9 is a cross-sectional view of the CC shown in Figure 6. One end of the second air tube 109B that is not connected to the air pipe 113 is closed by a cap member 125. The end of the second air tube 109B and the cap member 125 are tightened together by a hose clamp 123. Although not shown in the diagram, the same configuration is used for one end of the first air tube 109A that is not connected to the air pipe 113. In this way, the one end of the air tube 109 is closed and sealed by the cap member 125.

[0024] When air is drawn into the air pipe 113, it is drawn into the air tube 109. One end of the air tube 109 is closed, which equalizes the air pressure in the air pipe 113 and the air tube 109, thus creating pressure in the air tube 109.

[0025] Another form of the foundation structure 161 includes a deflection-allowing mechanism 101. In this case, the jack mechanism 127 is raised when the test specimen 5 is being formed. In its initial stages, the jack mechanism 127 pushes up the inner steel plate 111, holding the inner steel plate 111 in a horizontal position. The inner steel plate 111 is held horizontally, and the test specimen 5 is formed on the foundation structure 161 as described above. During the process of forming the test specimen 5, the jack mechanism 127 receives the load from the compaction of the test specimen 5. After the test specimen 5 is formed, the jack mechanism 127 is lowered.

[0026] Once the jack mechanism 127 is lowered, the load on the test specimen 5 thereafter acts on the air tube 109. When a load is applied to the air tube 109, the air tube 109 takes on a certain shape. If a buffer plate 114 is in place, the buffer plate 114 is removed before the jack mechanism 127 is lowered. When a jacking mechanism 127 is provided, the foundation structure 161 may be constructed with a mechanism other than the wedge member 65 shown in Figure 2. The jacking mechanism 127 and the air tube 109 are examples of a "flexure-allowing mechanism 101".

[0027] When the test begins, tire 27 moves, and a load is applied to test specimen 5. By providing the deflection tolerance mechanism 101, tests can be conducted under conditions similar to those of vibrations, deflections, and swaying that occur in actual paved roads, thereby reproducing a deterioration test of the test specimen 5 that closely resembles that of an actual paved road. The first air tube 109A and the second air tube 109B may have different air pressures. This allows for a wide range of changes in the state of the deflection tolerance mechanism 101. Furthermore, sensors for strain measuring devices that measure the deformation of the test specimen 5 may be installed at any point in each layer of the test specimen 5.

[0028] Furthermore, since the air tube 109 of the deflection-allowing mechanism 101 is provided only on the radially inner side of the test formwork 3, only the radially inner side of the test specimen 5 is supported by the air tube 109. As a result, a difference in deflection occurs between the outer and inner sides of the test specimen 5, making the test specimen 5 more susceptible to deterioration and improving the possibility of efficient testing. The air tube 109 may also be arranged over the entire radial length of the test formwork 3. In this case, the test formwork 3 does not have an outer foundation structure 161A.

[0029] With the outer steel plate 107 held in place by the jack mechanism 127, the test specimen 5 is formed within the test formwork 3. After the test specimen 5 is formed, when the jack mechanism 127 is lowered, the load on the test specimen 5 then acts on the air tube 109. As the tire 27 drives over the test specimen 5, a load is applied to the test specimen 5, causing the outer steel plate 107 to sink and the load to be applied to the air tube 109. At this time, the air tube 109 shrinks and deforms, and once the tire 27 has passed through the test specimen 5, the air tube 109 recovers due to air pressure and returns to its original fixed shape. During this process, the test specimen 5 temporarily bends.

[0030] When forming the test specimen 5, a granular roadbed layer 7 is placed on top of the base structure 161 of the deflection-allowing mechanism 101 and the heating device 71. At this time, by raising the jack mechanism 127 located in the center of the inner foundation structure 161B and supporting the inner steel plate 111, the test specimen 5 can be formed without applying a load to the air tube 109.

[0031] [1-2-4.Heating device] As described above, the foundation structure 61 comprises a square pipe 63 and a wedge member 65, and a heating device 71 is provided on the upper surface of the square pipe 63 and the wedge member 65, as shown in Figure 2. The heating device 71 heats the test specimen 5 inside the test formwork 3. As shown in Figure 3, the heating device 71 includes 14 heater bodies 73, and the multiple heater bodies 73 are arranged on the upper surfaces of the square pipes 63 and wedge members 65. The number of heater bodies 73 is not limited to 14. The wattage of each heater body 73 can be changed individually.

[0032] Figure 10 is an enlarged view of the regions indicated by α, β, and γ in Figure 2. As shown in regions α, β, and γ of Figure 10, the heating device 71 comprises an upper iron plate 79A, a lower iron plate 79B, and a base iron plate 91. The heater body 73 is positioned sandwiched between the upper iron plate 79A and the lower iron plate 79B. The upper iron plate 79A and the lower iron plate 79B are connected by multiple fasteners 81, and silicone resin is filled between the upper iron plate 79A and the lower iron plate 79B. The thickness of the heater body 73 is thinner than the gap between the two iron plates 79A and 79B.

[0033] In region β of Figure 10, a cushion 85 is inserted between the heater body 73 and the lower iron plate 79B during assembly. The heater body 73 is fixed with heat-resistant silicone 87 and pressed against the upper iron plate 79A by the cushion 85. All 14 heater bodies 73 shown in Figure 3 have the same configuration, fixed with heat-resistant silicone 87 and pressed against the upper iron plate 79A by the cushion 85. Below the lower steel plate 79B, a restricting member 89 is welded to regulate the distance between the lower steel plate 79B and the foundation steel plate 91. The restricting member 89 is a rectangular parallelepiped-shaped metal member. The foundation steel plate 91 is welded to the lower surface of the restricting member 89. A space S is formed between the foundation steel plate 91 and the lower steel plate 79B by the restricting member 89.

[0034] In region γ of Figure 10, multiple connecting members 93 are welded through the upper steel plate 79A, the lower steel plate 79B, and the foundation steel plate 91. Through holes are formed in the connecting members 93, and fasteners 95 are inserted through the through holes. The fasteners 95 pass through the square pipe 63 of the foundation structure 61 and are fixed to the concrete base 59 of the test formwork 3. The heating device 71 is provided on the square pipe 63 and the wedge member 65 and fixed to the base 59 via the fasteners 95, but is not limited to this, and the heating device 71 may be provided in any of the layers of the asphalt stabilization layer 9, base layer 11, and surface layer 13. When provided in any of the layers, the heating device 71 may be placed at the desired location when each layer is poured, and then the surface layer 13 may be compacted to form a test specimen 5 having the heating device 71 inside.

[0035] Multiple heater bodies 73 are connected by wiring 83, as shown in Figure 3. Each wire 83 is connected together to the harness connection part 77A of the upper iron plate 79A, as shown in area α of Figure 10, and then connected to the harness 77. As shown in Figure 2, the harness 77 rises upward inside the protective cover 79, which has a roughly L-shaped cross-section, and is connected to the terminal box 75. The terminal box 75 may be supported by the inner wall portion 49B or by another support base. As shown in Figures 2 and 3, the power line 75A is connected to the terminal box 75.

[0036] As described above, by providing the heating device 71 to the test specimen 5, the test specimen 5 can be tested under conditions similar to those that occur on actual paved roads, such as temperature rise on the paved road. Therefore, the deterioration of the test specimen 5 can be reproduced in the test under conditions similar to those that occur on actual paved roads. The temperature of the heating device 71 is set as appropriate, but is heated to, for example, 60 degrees Celsius or lower to correspond to the actual condition of the paved road surface.

[0037] [1-2-5. Water supply device] As shown in Figure 2, a water supply device 41 is connected to the test mold 3. The water supply device 41 includes a tank 45, to which a water supply hose 47 is connected. The tank 45 and the test mold 3 are connected by two connecting hoses 43. Water from the tank 45 is used to submerge part or all of the test specimen 5 inside the test mold 3.

[0038] As shown in Figure 3, the two connecting hoses 43 are connected to the test formwork 3 at two corners on the radially inner side of the test formwork 3. The radial direction is perpendicular to the rotation support shaft 19 in Figure 1. As shown in Figure 2, the connecting hoses 43 are connected to the water supply holes 43B in the inner wall portion 49B via the on-off valves 43A. The water supply hole 43B can be located anywhere inside the test formwork 3, as long as it can supply water above the concrete base 59. Water supplied from the water supply hose 47 is delivered from the tank 45 through the connecting hose 43 into the interior of the test formwork 3.

[0039] Water level confirmation holes 51 are formed in the outer wall portion 49A on the radially outer side of the test formwork 3. Multiple water level confirmation holes 51 are formed in a vertically aligned manner. The water level confirmation holes 51 can be closed with caps (not shown). This allows the water level inside the test formwork 3 to be confirmed by checking which water level confirmation hole 51 water is spraying out.

[0040] The tank 45 is equipped with a ball tap 53 inside. The ball tap 53 moves up and down in accordance with the water level in the tank 45. When the water level drops, the ball tap 53 lowers, the water supply valve opens, and water supply begins. When the tank is full, the ball tap 53 rises due to buoyancy, the water supply valve closes, and water supply stops. Since the water level in the tank 45 and the water level in the test formwork 3 are the same, the water level in the test formwork 3 can be controlled by the ball tap 53.

[0041] Furthermore, when water is supplied to the tank 45, water will also seep into the space S formed between the foundation steel plate 91 and the lower steel plate 79B, as shown in region β of Figure 10. In contrast, if the water supply is stopped and the space S is not filled with water, this space S becomes an air layer, improving its thermal insulation performance.

[0042] By connecting the water supply device 41 to the test formwork 3 and supplying water to the desired level into the test formwork 3, part or all of the test specimen 5 is submerged. This allows the test specimen 5 to be tested under conditions similar to those that occur on actual paved roads, where water accumulates on the road surface due to water retention in the pavement. Therefore, the deterioration of the test specimen 5, which is similar to the deterioration that occurs on actual paved roads, can be reproduced in the test.

[0043] [1-3. Formation of the specimen] As shown in Figure 2, the test formwork 3 comprises an outer wall portion 49A and an inner wall portion 49B, and fixing holes 55 are formed in the outer wall portion 49A and the inner wall portion 49B. The test formwork 3 is arranged side-by-side in a plan view on the inner frame 35A, which is polygonal and annular in a plan view, and the outer frame 35B, which is also polygonal and annular in a plan view. Then, bolts are inserted through the fixing holes 55, and adjacent test formwork 3 are connected side-by-side. A test specimen 5 is formed on each of the base structures 61 of the interconnected test formwork 3. While the test specimen 5 is being formed inside the test formwork 3, the sides of the test formwork 3 are closed by side walls (not shown). The side walls (not shown) are fixed to the outer wall 49A and the inner wall 49B with fasteners.

[0044] In the test specimen 5, the granular base course layer 7 is first placed inside the test formwork 3, followed by the asphalt stabilization layer 9, the base layer 11, and the surface layer 13 in that order. The surface layer 13 is then compacted to form the surface layer 13. Note that the base layer 11 may be omitted from each layer of the specimen 5.

[0045] [2. Test Method] A test specimen 5 is formed inside the test formwork 3, and multiple test formworks 3 are arranged in a polygonal ring shape around the rotating support shaft 19 of the pavement testing machine 1. In this case, different devices or mechanisms such as a heating device 71, a water supply device 41, or a deflection tolerance mechanism 101 may be arranged in combination for each test formwork 3. Furthermore, for each of the 5 test specimens, the material of any of the layers, such as the granular base layer 7, the asphalt stabilization layer 9, the base layer 11, and the surface layer 13, may be changed. The set temperature of the heating device 71, the amount of water supplied by the water supply device 41, or the air pressure of the air tube 109 of the deflection tolerance mechanism 101 may be set as appropriate.

[0046] After forming the test specimen 5 within the test formwork 3 and arranging the test formwork 3 in a ring, the pavement testing machine 1 is driven to roll the tires 27. The load applied by the tires 27, or the rolling speed of the tires 27, can be changed as appropriate. This test is primarily conducted to investigate the deterioration of the test specimen 5 due to the movement of the tire 27. The faster the deterioration of the test specimen 5 progresses, the more efficient the test is. Therefore, a faster rolling speed of the tire 27 is preferable.

[0047] After rolling the tire 27 for a predetermined time, the test formwork 3 is removed and the condition of the deteriorated test specimen 5 is examined. Next, the conditions for the test specimen 5 are changed and the test is performed again. These steps are repeated. According to this embodiment, the deterioration state of multiple test specimens 5 can be efficiently tested in conditions close to those of an actual paved road surface.

[0048] [3. Effects] As described above, the pavement testing machine 1 in this embodiment comprises a test formwork 3, a test specimen 5 formed on a foundation structure 161 within the test formwork 3, and a tire 27 that rolls on the test specimen 5. The test specimen 5 is made of pavement material, and the foundation structure 161 includes a deflection-allowing mechanism 101 that allows deflection of the test specimen 5. With this configuration, the test specimen 5, which is made of paving material, flexes due to the deflection-allowing mechanism 101, thus reflecting the actual condition of the paved road.

[0049] Furthermore, the deflection-allowing mechanism 101 includes an air tube 109 that compresses when the tire 27 is placed on the test specimen 5, and returns the test specimen 5 to its original position after the tire 27 has passed over the test specimen 5. In this configuration, the air tube 109 undergoes deformation close to elastic deformation, causing the test specimen 5 to bend and sway. Therefore, it can reflect the actual condition of the paved road.

[0050] Furthermore, the test formwork 3 is equipped with a harness 77 connected to a heating device 71, the harness 77 being routed in the corners inside the test formwork 3, and the test formwork 3 is equipped with a protective cover 79 that covers the harness 77 and separates it from the test specimen 5. This configuration makes it possible to prevent the harness 77 from failing when the test specimen 5 is installed or due to the weight of the test specimen 5.

[0051] Furthermore, the air tube 109 comprises a plurality of first air tubes 109A and a plurality of second air tubes 109B, the first air tubes 109A being connected to one air pipe 113A of the test mold 3, and the second air tubes 109B being connected to the other air pipe 113B. With this configuration, air can be filled into multiple air tubes 109 simply by supplying air to the air pipe 113, making the work easy. Furthermore, by setting different air pressures in the first air tube 109A and the second air tube 109B, tests can be conducted under various conditions, and it becomes easier to reproduce conditions close to those of an actual paved road.

[0052] Furthermore, the deflection-allowing mechanism 101 includes a jack mechanism 127 that supports the test specimen 5 from below, and air is filled into the air tube 109 while the test specimen 5 is lifted from below by the jack mechanism 127. With this configuration, the load on the test specimen 5 is applied only after the air tube 109 reaches a predetermined air pressure. This allows the test to be conducted with the air tube 109 inflated, enabling the test specimen 5 to exhibit deflection and vibration.

[0053] Furthermore, the test formwork 3 is formed in a roughly trapezoidal shape in plan view, and multiple test formworks 3 are arranged side by side in the circumferential direction, and the tire 27 rolls in the circumferential direction over multiple test specimens 5 formed within the test formwork 3. This configuration allows the tires 27 to be efficiently driven on the test specimen 5, which reflects conditions close to those of an actual paved road, thereby streamlining the testing of the test specimen 5.

[0054] (Other embodiments) The above embodiments illustrate one specific example of applying the present invention and do not limit the forms to which the invention is applied.

[0055] In the embodiment described above, a configuration in which multiple test molds 3 are arranged in a ring was illustrated, but the invention is not limited to this. For example, the test formwork 3 may be rectangular in plan view and arranged in a straight line, and the tires 27 may be configured to roll back and forth over multiple test specimens 5. The test may also be performed with at least one wedge member 65 removed.

[0056] By combining the heating device 71 and the water supply device 41 in a single test mold 3, the test specimen 5 can be tested in conditions that closely resemble those that occur on actual paved roads, where high-temperature water accumulates on the road surface due to the rise in pavement temperature and water retention. This allows for a more accurate reproduction of the deterioration of the test specimen 5, which closely resembles the deterioration that occurs on actual paved roads.

[0057] By combining the water supply device 41 and the deflection tolerance mechanism 101 in a single test formwork 3, tests can be conducted under conditions that closely resemble those occurring in actual paved roads, involving a combination of water accumulation, vibration, deflection, and shaking. This allows for more accurate reproduction of the deterioration of the test specimen 5, which closely resembles the deterioration that occurs in actual paved roads.

[0058] A single test formwork 3 can be used to combine the heating device 71, the water supply device 41, and the deflection tolerance mechanism 101. This allows for testing under conditions that closely resemble those of actual paved roads, such as vibration, deflection, shaking, water accumulation, and temperature rise of the paved road. Therefore, the deterioration of the test specimen 5, which closely resembles the deterioration that occurs in actual paved roads, can be reproduced with greater accuracy. [Explanation of Symbols]

[0059] 1. Pavement testing machine 3. Test formwork 5 Specimen 19 Rotating support shaft 27 tires 41 Water supply equipment 43. Connection hose 45 tanks 47 Water supply hose 51 Water level confirmation hole 53 Ball Tap 59 Base 61, 161 Basic structure 71 Warming device 73 Heater body 101 Deflection tolerance mechanism 109 Air Tube 109A First air tube 109B Second air tube 113 Air tube 115 Intake hose 127 Jacking mechanism 129 Jack section 131 Lifting platform

Claims

1. Test formwork and, A test specimen formed on the foundation structure within the aforementioned test formwork, The vehicle comprises a tire that rolls over the specimen, The aforementioned test specimen is made of paving material, The aforementioned foundation structure is The specimen is equipped with a deflection-allowing mechanism that allows for deflection of the specimen, The aforementioned deflection-allowing mechanism is, When the tire is placed on the test specimen, it compresses, The tire is equipped with an air tube that returns the test specimen to its original position after it has passed over it. Pavement testing machine.

2. The aforementioned air tube is It comprises multiple first air tubes and multiple second air tubes, The first air tube is connected to one air pipe of the test formwork, and the second air tube is connected to the other air pipe. The pavement testing machine according to claim 1.

3. The aforementioned deflection-allowing mechanism is, The device is equipped with a jacking mechanism that supports the test specimen from below, With the test specimen lifted from below by the jack mechanism, air is filled into the air tube. The pavement testing machine according to claim 1 or 2.

4. A test mold and, A test specimen formed by compacting paving material on a foundation structure within the aforementioned test formwork, The vehicle comprises a tire that rolls over the specimen, The aforementioned foundation structure is Multiple square pipes supporting the aforementioned test specimen, Multiple wedge members are arranged to fill the gaps between the aforementioned square pipes and are removable, The specimen comprises a deflection-allowing mechanism that allows for deflection of the specimen, The aforementioned deflection-allowing mechanism is, After the specimen is formed, the gap created by pulling out the wedge member from between the foundation structure and the specimen is formed. Pavement testing machine.

5. The aforementioned test formwork is formed in a roughly trapezoidal shape in plan view. Multiple test molds are arranged side by side in the circumferential direction, and the tire rolls circumferentially over multiple test specimens formed within the test molds. The pavement testing machine according to claim 1 or 4.

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