Test Unit

Abstract

To provide a test unit capable of easily manufacturing a regenerated asphalt material from an asphalt waste material.SOLUTION: A test unit for analyzing the content of an effective asphalt component of an asphalt mixture comprises a test vessel having a bottomed cylindrical shape of a predetermined diameter, at least one test sheet cut into a circle approximately equal to the inner diameter of the test vessel, and a tamping rod to tamp the asphalt mixture from the top of first test paper included in the at least one test paper, which is covered over the asphalt mixture loaded in the test container.SELECTED DRAWING: Figure 4D

Description

[Technical field]

[0001] The present invention relates to a test unit for analyzing the content of effective asphalt components in an asphalt mixture for an asphalt pavement, for example, laid on a road. [Background technology]

[0002] Many roads, both in urban and suburban areas, are paved with asphalt. For asphalt pavement, an asphalt mixture made by mixing aggregates such as crushed stone and sand with petroleum asphalt is used. Asphalt mixtures deteriorate over time. For example, the pavement layer (the surface layer of the asphalt mixture) hardens due to ultraviolet rays, causing cracks on the surface of the pavement layer, ruts appear in the pavement layer due to contact with automobile tires, and depressions occur in the pavement layer due to the weight of vehicles and objects falling onto the road. For this reason, for asphalt pavement that has been in operation for a certain period of time, the deteriorated pavement layer (the surface layer of the asphalt mixture) is peeled off from the base layer called the roadbed, and a new pavement layer made of asphalt mixture is laid in its place. Also, even on roads that have been in operation for a short time, it is necessary to repair depressions.

[0003] In recent years, unpaved roads are being replaced with asphalt-paved roads even in islands and developing countries. However, in such islands and developing countries, manufacturing plants for the asphalt mixture required for paving are not necessarily located nearby. For this reason, it is difficult to prepare new asphalt mixture at the construction site when constructing a new asphalt pavement, repaving, or repairing it. Considering such cases, it is desirable to heat the solidified material of new asphalt mixture prepared in advance at the construction site, or to recycle and reuse deteriorated asphalt mixture from existing asphalt pavement.

[0004] When using asphalt mixture produced at a manufacturing plant as new asphalt mixture, the produced asphalt mixture needs to be transported from the manufacturing plant to the construction site by a transportation means such as a truck. In addition, the asphalt pavement layer (waste asphalt) peeled off at the construction site needs to be transported from the construction site to the manufacturing plant or disposal site. On the other hand, when using recycled asphalt waste at the construction site as new asphalt mixture, the time, cost, and effort required for manufacturing and transporting new asphalt mixture can be reduced. In addition, since it is possible to reuse asphalt waste that would otherwise become industrial waste, it is in line with the goals of the SDGs (Sustainable Development Goals), and the benefits are great not only for islands and developing countries, but also for all countries and regions with asphalt-paved roads.

[0005] Regarding the regeneration of asphalt, the following Patent Document 1 discloses an apparatus for regenerating asphalt waste by introducing the waste asphalt into a rotating drum, rotating the rotating drum in a circumferential direction at an angle, and blowing hot air into the rotating drum. In addition, the following Patent Document 2 discloses that a trailer equipped with an asphalt regeneration device is coupled to a towing vehicle for transport to a construction site, the trailer is detached from the towing vehicle and coupled to the blade of a hydraulic excavator, and while excavating the site with the hydraulic excavator, the excavated asphalt mixture (waste asphalt) is fed into the asphalt regeneration device to regenerate the asphalt mixture, and the regenerated asphalt mixture is successively laid on the site after excavation to construct an asphalt pavement. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2001-90018 A [Patent Document 2] Patent No. 4892711 Summary of the Invention [Problem to be solved by the invention]

[0007] In Japan, quality standards are set for various items regarding the physical properties of asphalt for paving. For example, the JIS standard (JIS K 2207) indicates the target physical properties of petroleum asphalt suitable for road paving. The JIS standard includes an item for penetration. This penetration is an index that indicates the hardness of solidified petroleum asphalt. A specified needle, about the size of a sewing needle with a weight of 100 g attached, is pressed against an asphalt sample at 25°C, and the needle is allowed to penetrate vertically into the asphalt sample for 5 seconds under its own weight, and the length of penetration of the needle into the asphalt sample is measured. The penetration depth is then expressed in units of 1 / 10 mm to determine the hardness of the asphalt. For asphalt for road paving, the penetration is required to be within a specified range, for example, more than 40 and less than 60 for general areas excluding cold regions. If the penetration is within this range, the softening point, elongation, strength, viscosity, etc. of the asphalt also tend to be suitable for paving.

[0008] When waste asphalt is recycled into asphalt mixture at a construction site, the recycled asphalt must meet the above-mentioned prescribed penetration level. However, it is not easy to produce an asphalt mixture with a penetration level that meets the standard at a construction site with limited facilities.

[0009] The present invention has been made in consideration of the above circumstances, and aims to provide a test unit that can easily produce recycled asphalt material that complies with standards from waste asphalt material that was used in existing asphalt pavement at asphalt pavement construction sites. [Means for solving the problem]

[0010] The test unit of the present invention is a test unit for analyzing the content of effective asphalt components in an asphalt mixture, and the test unit comprises a cylindrical test container with a bottom and a predetermined diameter, at least one test paper cut into a circle approximately equal to the inner diameter of the test container, and a tamping rod placed on top of the asphalt mixture loaded into the test container and used to tamp the asphalt mixture from above the first test paper included in the at least one test paper. In the test unit of the present invention, the at least one test paper includes the first test paper and a second test paper, the second test paper being placed on the bottom of the test container before the asphalt mixture is loaded into the test container, and the first test paper being placed on top of the asphalt mixture after the asphalt mixture is loaded into the test container. Effect of the Invention

[0011] According to the present invention, recycled asphalt material that meets standards can be easily produced at an asphalt pavement construction site from waste asphalt material that was used in existing asphalt pavement. [Brief description of the drawings]

[0012] [Figure 1] FIG. 2 is a side view of a regeneration device used to carry out the regeneration method according to the present invention. [Diagram 2] FIG. 2 is a schematic vertical cross-sectional view of the drum in FIG. [Diagram 3] 3 is a cross-sectional view of the drum taken along line III-III in FIG. 2. [Figure 4A] FIG. 1 is a schematic diagram showing the procedure for performing an analysis of effective asphalt components. [Figure 4B] FIG. 1 is a schematic diagram showing the procedure for performing an analysis of effective asphalt components. [Figure 4C] FIG. 1 is a schematic diagram showing the procedure for performing an analysis of effective asphalt components. [Figure 4D] FIG. 1 is a schematic diagram showing the procedure for performing an analysis of effective asphalt components. [Diagram 5] FIG. 1 is a diagram showing a table used to identify the amount of additive required for regenerating waste asphalt. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Preferred embodiments of the present invention will now be described. The asphalt regeneration device 1 used to carry out the method for regenerating waste asphalt mixture (hereinafter referred to as waste asphalt) according to the present invention may be fixedly installed in a factory or the like, but is preferably used mounted on a dolly equipped with a towing section, the loading platform of a self-propelled vehicle, etc. In this case, the regeneration device 1 can be freely moved between asphalt pavement construction sites by moving the dolly or vehicle, etc.

[0014] The regeneration device 1 of this embodiment has the following structure. That is, as shown in Figures 1 to 3, the asphalt regeneration device 1 has a base 2a, a tilt mechanism 2b, a frame 2, a drum 3 for regenerating waste asphalt mixture (hereinafter referred to as waste asphalt), drum rollers (supporting parts) 4 and 5 that rotatably support the drum 3, a driving part (driving unit) 6 that rotates the drum 3 around a rotation axis O that is a virtual rotation center, and a burner 7 that heats the inside of the drum 3. The tilt mechanism 2b and the frame 2 are arranged on the base 2a. In addition, the drum 3, the drum rollers 4 and 5, the driving part 6, and the burner 7 are arranged on the frame 2. The drum 3 is supported by the drum rollers 4 and 5. The drum roller 5 is arranged on the back side of the drum 3 (the back side of the drum 3 in Figure 1), so it is not shown in Figure 1.

[0015] The frame 2 is composed of upper and lower frame members connected via a hinge portion, and the lower frame member is fixed to the base 2a. The base 2a is provided with a tilt mechanism 2b that tilts the frame 2 (upper frame member). When the tilt mechanism 2b is operated, the upper frame member is tilted so that the inlet 11 of the drum 3 is higher than the outlet 12. The tilt angle of the upper frame member can be selected arbitrarily by changing the stroke length of the tilt mechanism. The tilt mechanism 2b is composed of, for example, a fluid cylinder.

[0016] The drum 3 is a container for heating the waste asphalt and additives while stirring them inside, and is a hollow metal body into which the waste asphalt is supplied via a hopper 16. The drum 3 includes a cylindrical main body 9 and a truncated conical discharge section 10. The main body 9 is surrounded by a gate-shaped frame provided on the base 2a. The main body 9 has an inlet 11 (see FIG. 2) at its front end, and the waste asphalt fed into the hopper 16 is introduced into the drum 3 through the inlet 11. The discharge section 10 forms the rear of the drum 3, and has a discharge port 12 for discharging the regenerated asphalt mixture. The discharge port 12 can be closed with a cover member 24.

[0017] A male screw is provided on the outer periphery of the rod 25 fixed to the discharge portion 10, and a female screw hole is provided in the center of the handle 26. A hole slightly larger than the outer diameter of the rod 25 is provided in the center of the cover member 24, and the rod 25 is inserted into the hole. The handle 26 is provided by screwing onto the rod 25 from the outside of the cover member 24, and by operating the handle 26, the cover member 24 is moved in the axial direction of the rod 25, thereby adjusting the gap between the discharge port 12 and the cover member 24. By adjusting this gap, the amount of recycled asphalt mixture discharged from the discharge port 12 can be adjusted.

[0018] The drum 3 is rotatably supported on the frame 2 via a number of drum rollers 4, 5. In the position shown in FIG. 1 (normal state), the rotation axis O of the drum 3 faces the horizontal direction. The drum rollers 4, 5 include rollers 41, 51 that can rotate around a roller rotation axis that is provided parallel to the rotation axis O, and the rollers 41, 51 abut against the outer circumferential surface of the main body 9 to rotatably support the drum 3. There are a total of four drum rollers 4, 5, one each at the front and rear in the longitudinal direction of the drum 3 as shown in FIG. 1, and one each at the left and right in the width direction of the drum 3 as shown in FIG. The rollers 41, 51 of each drum roller 4, 5 support the drum 3 from below.

[0019] The drive unit 6 is a drive source that rotates the drum 3. The drive unit 6 includes a motor 20, a reducer 22, and a pinion gear (not shown). The output of the motor 20 is reduced in speed by the reducer 22 to rotate the pinion gear. An annular drive transmission unit 21 is provided on the outer circumferential surface of the main body 9. The drive transmission unit 21 is a number of teeth (racks) that mesh with the pinion gear, and is formed in an annular shape. As the motor 20 rotates, the teeth mesh with the pinion gear, and the drum 3 rolls on each of the rollers 41, 51 around the rotation axis O.

[0020] The rotation speed of the drum 3 can be adjusted by an operation panel (not shown). The operation panel is provided with a switch for switching the rotation speed of the drum 3 between stop, low speed, medium speed, and high speed. By operating this switch, the worker can appropriately switch the rotation speed depending on the size of the asphalt waste material lumps and the progress of the heating and mixing processes.

[0021] The burner (heating unit) 7 heats the waste asphalt and its crushed recycled granules loaded inside the drum 3. In the present embodiment, the burner 7 radiates (projects) a flame into the inside of the drum 3 through the inlet 11. The waste asphalt inside the drum 3 is directly heated by this flame, so that the waste asphalt can be quickly and efficiently softened (the surface layer melted).

[0022] The temperature inside the drum 3 can be appropriately set by an operator using a temperature input means provided on the operation panel. The burner 7 controls the heating based on the temperature set by the operator and the measurement result of a temperature measuring means provided inside the drum 3.

[0023] Burner 7 applies pressure to liquid fuel to spray it in the form of a mist, which is then mixed with air and ignited to emit a flame. In the case of a single burner with one flame outlet, it is possible to control the heating by turning on and off burner 7. In the case of a dual burner with two flame outlets, one for high flame and one for low flame, it is possible to control the heating by adjusting the operation timing of each burner. Burner 7 may be of a triple or more type.

[0024] In the recycling device 1 configured as described above, when recycling asphalt waste, asphalt waste and additives are put into the hopper 16 as shown in Fig. 1. This is done by a shovel car or a hopper hanging crane. The amount of asphalt waste put in is measured in real time by a measuring unit (not shown) provided in the recycling device 1, and the putting in is stopped when the put in amount reaches the desired amount.

[0025] While driving the drive unit 6 to rotate the drum 3, the burner 7 heats the waste asphalt inside the drum 3. The asphalt waste loaded in the drum 3 is crushed into lumps by the falling energy accompanying the rotation of the drum 3. The crushed bodies are heated to melt the surface layer, and are granulated by rolling inside the drum 3. In addition, by continuing to heat the waste asphalt with the burner 7 for a predetermined time while maintaining the temperature inside the drum 3 at a predetermined temperature, the waste asphalt can be regenerated into asphalt with a high yield and good quality, and regenerated granules can be obtained. The obtained regenerated granules are discharged from the drum 3 and reused for asphalt paving of roads. When discharging, the frame 2 is rotated around the hinge part by driving (extending) the tilt mechanism 2b, and lifted up. As a result, the drum 3 changes to an oblique position with the rear end (lid member 24) facing downward. During this position change, heating by the burner 7 and driving of the drive unit 6 may be continued. When the cover member 24 is operated in the opening direction by operating the handle 26, a gap is secured between the cover member 24 and the discharge portion 10, and the recycled grains inside the drum 3 fall naturally from this gap due to their own weight.

[0026] A plurality of guide members 19 are provided on the inner peripheral wall of the discharge section 10. The guide members 19 are plate-shaped members, and are provided at an angle to the radial lines extending from the center of the discharge port 12 along the inner peripheral wall. The guide members 19 are inclined so that their rear ends face the rotation direction of the drum 3, and the rear ends are curved in an arch shape toward the opposite side to the rotation direction. The guide members 19 guide the recycled grains granulated inside the main body 9 to the discharge port 12, and can efficiently discharge them. A plurality of guide members 18B are also provided in the circumferential direction on the inner peripheral wall at the rear of the main body 9, and guide the movement of the recycled grains from the main body 9 to the discharge section 10.

[0027] A plurality of blade members 18A are also provided on the inner peripheral wall of the main body 9. The blade members 18A are arranged at intervals in the circumferential direction of the drum 3. In the case of a drum without the blade members 18A, even if the drum is rotated in the position shown in FIG. 1, the asphalt waste material remains accumulated at the bottom of the drum due to its own weight. On the other hand, in the case of a drum 3 having the blade members 18A, the asphalt waste material is forcibly lifted without accumulating at the bottom of the drum 3 by the plurality of blade members 18A scraping up the asphalt waste material as the drum 3 rotates, and then the asphalt waste material falls naturally and is agitated within the drum 3.

[0028] Each blade member 18A is provided on the inner circumferential wall of the main body 9 along the direction of the rotation axis O and protrudes radially inward of the drum 3. In this embodiment, each blade member 18A extends continuously in parallel to the direction of the rotation axis O.

[0029] Next, the regeneration of waste asphalt using the asphalt regeneration device 1 having the above-mentioned structure will be described. When excavating an existing asphalt pavement layer at a site where the layer is being replaced, various sizes of excavated rubble are generated, which will become the waste asphalt that will be used to construct the new asphalt pavement layer.

[0030] (Analysis of effective asphalt components) Although the size of the particles in the asphalt waste is uniform to the same extent as the aggregate in the asphalt mixture, the petroleum asphalt components are not necessarily of a quality suitable for use in actual asphalt pavement. This is because pebbles and sand grains that were on the roadbed, which is the base of the previous asphalt pavement layer, are also taken in during excavation. Since it is not possible to completely remove these pebbles and sand grains from the asphalt waste, the asphalt waste must be recycled while still containing the pebbles and sand grains. In addition, problems of deterioration over time, such as hardening and oxidation of the asphalt components, occur when the asphalt pavement layer is exposed to rainwater, ultraviolet rays, and air for a long period of time outdoors. Thus, due to the inclusion of impurities and deterioration over time, if this asphalt waste is directly used to produce recycled asphalt, only low-quality recycled asphalt is obtained, with a low content of effective petroleum asphalt components, i.e., effective asphalt components, compared to the aggregate. In other words, recycled asphalt produced from this waste asphalt does not meet the quality standards required for asphalt for road paving, and therefore cannot be used for repaving. Therefore, when producing recycled asphalt from waste asphalt, it is necessary to know in advance the amount of effective asphalt components contained in the waste asphalt obtained from the construction site.

[0031] First, as shown in Figs. 4A to 4D, a test container 30 having a bottomed cylindrical shape with a predetermined diameter and two pieces of white filter paper 31, 32 cut into a circle approximately equal to the inner diameter of the container are prepared. Then, the first piece of filter paper 31 is laid on the bottom of the test container 30 (see Fig. 4A). Next, a part 102 of the asphalt mixture as a sample taken from the asphalt waste material is loaded into the test container 30 so as to cover the first piece of filter paper 32 (see Fig. 4B). Next, the asphalt mixture 102 loaded into the test container 30 is tamped down using a tool such as a tamping rod and the surface is leveled. The asphalt mixture 102 loaded into the test container 30 is heated to 170 to 200° and crushed to a predetermined grain size.

[0032] After placing a second filter paper 32 on the leveled asphalt mixture 102 (see FIG. 4C), the asphalt mixture 102 is further compacted using a tamping rod 33 (see FIG. 4D). This causes the effective asphalt components to seep out of the asphalt mixture 102 and adhere to the filter papers 31 and 32. The effective asphalt components adhering to the filter papers 31 and 32 appear as black stain-like patterns. The amount of asphalt mixture 102 loaded into test container 30 is adjusted so that the layer thickness of asphalt mixture 102 in test container 30 is approximately equal to the construction thickness (80 to 120 mm) defined in the asphalt pavement specifications.

[0033] After the asphalt mixture 102 has been tamped, the filter paper 32 is peeled off from the asphalt mixture. The area of ​​the black pattern on the filter paper 32 is then analyzed to determine the percentage of the total area of ​​the filter paper 32, and the amount of effective asphalt components contained in the sample asphalt mixture 102 is determined based on this analysis value. The "area of ​​the pattern" here is represented by the ratio of the white and black areas to the total area of ​​the filter paper. By identifying the amount of effective asphalt components contained in the sample, the asphalt waste material from which the sample was derived can be determined. 1) Whether or not it meets the quality standards required for asphalt for road paving, 2) If the quality standards are not met, how much of the effective asphalt component is lacking? Based on the result of the judgment in 2), the amount of additive to be added to the waste asphalt material to make up for the insufficient effective asphalt component can be determined.

[0034] The additive contains at least one polymeric material selected from petroleum asphalt, rubber, thermoplastic elastomer, and thermoplastic resin, and asphalt emulsion as main components. The "additive" used in this embodiment refers to a mixture of the above-mentioned components, which is kneaded with a flammable binder and solidified into a block (hereinafter referred to as an additive block).

[0035] In determining the amount of additive to be added to the waste asphalt, first, a first table showing the relationship between the area ratio of the black pattern and the amount of effective asphalt component contained in the sample is prepared in advance using multiple types of waste asphalt samples. Similarly, a second table showing the relationship between the amount of effective asphalt component contained in the sample and the amount of additive required to make up for the deficiency of the effective asphalt component is prepared. After preparing these tables in advance, the amount of additive to be added to the waste asphalt is determined from the area ratio of the black pattern of the sample obtained from the waste asphalt at the construction site of the asphalt pavement and the first and second tables.

[0036] The amount of additive to be added to the waste asphalt material increases as the area ratio (adhesion rate) of the black pattern of the effective asphalt components adhered to the filter paper 32 to the total area of ​​the filter paper decreases, and decreases as the area ratio of the black pattern increases. To specifically explain the method for determining the amount of additive from stains on the filter paper 32, the area occupied by the effective asphalt components attached to the filter paper 32 can be calculated, for example, using image analysis software running on a general-purpose computer. First, the filter paper 32 with the effective asphalt component attached is photographed, and the digital image is run through image analysis software. The image analysis software calculates the area ratio of the black pattern of the effective asphalt component to the total area of ​​the filter paper 32 (= (total area of ​​the pattern ÷ total area of ​​the filter paper) × 100) from the black and white shading on the filter paper 32. Then, the amount of the effective asphalt component contained in the asphalt mixture 102 obtained as a sample is identified based on the relationship between the ratio of the area of ​​the pattern of the effective asphalt component calculated from the image of the filter paper 32 and the first table. Regarding the filter paper, in this embodiment, the occupied area ratio of the pattern of the effective asphalt component was calculated using filter paper 32, but the occupied area ratio may be calculated in a similar manner using filter paper 31, or the occupied area ratio may be calculated using two sheets of filter paper, 31 and 32, and the average occupied area ratio of the two sheets may be adopted.

[0037] <Decision process> After the amount of effective asphalt components contained in the sample is identified, the amount of additive required to make up for the deficiency in the effective asphalt components is determined based on the relationship between this amount and the second table. Since the additive block is a block body with a fixed weight per unit, the amount of additive determined above can be added reliably without error.

[0038] When producing recycled asphalt from waste asphalt, taking into consideration the quality standards required for asphalt for road paving, the weight of the additive block added to the waste asphalt is typically 1 to 4 kg per 1,000 kg of waste asphalt, and preferably 2 to 3 kg. If the weight of the additive block added to 1000 kg of asphalt waste is less than 2 kg, the penetration into the recycled asphalt pavement layer laid using the recycled asphalt may be small, and the quality standard may not be met. Furthermore, if the weight of the additive block added is less than 1 kg, the effective asphalt component is too small, so the penetration into the recycled asphalt pavement layer will be even smaller. In addition, the viscosity (hardness) of the asphalt will increase, resulting in poor flexibility, making the recycled asphalt pavement layer poorly conformable to uneven roadbeds, making laying and construction itself difficult.

[0039] In addition, if the weight of the additive block added to 1000 kg of asphalt waste is more than 3 kg, the penetration into the recycled asphalt pavement layer may be too high, and the quality standard may not be met. Furthermore, if the weight of the additive block added is more than 4 kg, the effective asphalt component is too high, and the penetration into the recycled asphalt pavement layer will be higher. In addition, the strength of the asphalt will decrease, so the durability of the recycled asphalt pavement layer may decrease, and cracks and ruts may occur in a short period of time after construction.

[0040] (Recycling waste asphalt) <Input process> First, the waste asphalt and additive blocks are put into the hopper 16 of the asphalt regeneration device 1 that has been moved to the site, and the waste asphalt and additive blocks are loaded into the drum 3. The amount of additive blocks to be added is determined based on the analysis results described above. The tilt mechanism 2b is operated to tilt the frame 2 together with the drum 3 so that the inlet 11 of the drum 3 is slightly higher than the outlet 12. By making the inlet 11 higher than the outlet 12, the asphalt waste material being processed in the drum 3 moves from the inlet 11 toward the outlet 12 by its own weight.

[0041] <Stirring and heating process> Next, the drive unit 6 is operated to rotate the drum 3, and a crushing process is performed so that the waste asphalt and additive blocks have a predetermined particle size. In parallel with this crushing process, the burner 7 is ignited to heat the inside of the drum 3 to a temperature range of 170°C to 200°C.

[0042] The asphalt waste and additive blocks fed into the drum 3 are initially in the form of lumps of various sizes, but as the drum 3 rotates, the wing members 18A repeatedly scoop them up and drop them, gradually crushing them (reducing their diameter). At the same time, the crushed asphalt waste and additive blocks are heated by the burner 7, softening the petroleum asphalt contained in the asphalt waste and additive blocks and increasing their viscosity.

[0043] The asphalt waste and additive blocks are crushed in drum 3 and have their viscosity increased by heating. While continuing to be stirred and heated, the waste asphalt and additive blocks are stirred and heated until they reach a specified temperature range, i.e., a temperature range of 170°C to 200°C, and reach a specified particle size, i.e., a particle size large enough to be used as aggregate for asphalt pavement (medium gravel, particle size: 4.75 to 19.00 mm). This heat treatment crushes and heats the waste asphalt and additive blocks. As a result, the surface layers of both crushed bodies are melted and stirred, so that both crushed bodies are mixed together to produce a homogeneous recycled asphalt material (recycled granules).

[0044] The recycled asphalt material produced in the drum 3 is discharged from the drum 3 at any timing. At this time, the tilt mechanism 2b is driven (extended) to rotate the frame 2 about the hinge portion, and the front end side (left side in FIG. 1) of the drum 3 is lifted up. This causes the drum 3 to change to an oblique position with the rear end side (the side of the lid member 24) facing downward. During this position change, heating by the burner 7 and rotation of the drum 3 by the drive unit 6 may continue. As the drum 3 changes position, the recycled granules inside the drum 3 are pulled toward the rear end of the drum 3 by their own weight, and are collected toward the center of the drum 3 by the guide members 18B, 19. After that, when the lid member 24 is operated in the opening direction by operating the handle 26, a gap is created between the discharge port 12 and the lid member 24, and the recycled granules inside the drum 3 fall naturally from this gap by their own weight. The discharged recycled granules are spread on the roadbed from which the asphalt pavement layer has been peeled off, and are used for asphalt pavement as recycled asphalt material.

[0045] As described above, according to the regeneration method of the present embodiment, the waste asphalt used in the existing asphalt pavement is analyzed, the amount of additive to be added to the waste asphalt is determined, and the waste asphalt and the additive are heated and stirred together, so that a recycled asphalt material that meets the standard can be easily produced from the waste asphalt. As a result, a high-quality recycled asphalt material that meets the quality standard can be easily produced at the construction site from the waste asphalt pavement layer that was used in the existing asphalt pavement.

[0046] In the above explanation, a general-purpose computer was used to determine the amount of additive from the pattern of the effective asphalt components attached to the filter papers 31 and 32, but it is assumed that there may be an environment where such electronic devices cannot be used on-site. Therefore, a method for determining the amount of additive without using electronic devices will be explained.

[0047] First, from the past cases included in the first table, several representative cases are selected in stages according to the area ratio of the pattern of the effective asphalt component formed on the filter paper. For example, case (1) obtained by performing the above analysis using asphalt mixture that can be used for paving as a sample, case (2) obtained by performing the above analysis using asphalt waste material that was laid about 3 years ago as a sample, case (3) obtained from asphalt waste material that was laid about 7 years ago as a sample, and case (4) obtained from asphalt waste material that was laid more than 10 years ago as a sample are selected. Then, for each of these cases, the amount of additive (kg / ton) required in each case is identified by referring to the second table. Then, as shown in Figure 5, a list is created in which the digital image of the filter paper in each case corresponds to the amount of additive required in each case. The amount referred to here is the amount of additive added per ton of asphalt waste material.

[0048] When constructing an asphalt pavement, the worker brings the above list to the site. This list may be printed on paper or may be saved as a digital image on a commercially available general-purpose computer, a mobile terminal with a display, or the like. Then, a sample of asphalt mixture 102 is obtained from the asphalt waste material from the site, and the asphalt mixture 102 is placed in a test container 30 and tamped to allow the effective asphalt components to soak into the filter paper 32. The filter paper 32 is then removed from the test container 30.

[0049] The worker compares the appearance of the filter paper 32 obtained at the site with the image of the filter paper of each case included in the list above, and identifies the case that is closest to the exclusive state of the pattern of the filter paper 32 obtained at the site. Then, the amount of additive required in that case is identified as the amount of additive to be added to the asphalt waste material obtained at the site. If there is no case that is close to the exclusive state of the pattern of the filter paper 32 obtained at the site, and for example, it appears to have less black ground area than the image of case (2) and more black ground area than the image of case (3), the average amount (2.25 kg / ton) of the amount of additive in case (2) (2.0 kg / ton) and the amount of additive in case (3) (2.5 kg / ton) is identified as the amount of additive to be added to the asphalt waste material at the site.

[0050] In this way, even if the construction site is not in an environment where a general-purpose computer can be operated, the amount of additives can be easily determined without imposing an undue burden on the workers. For example, this is particularly advantageous in construction sites in harsh environments such as extreme cold and scorching heat, or in sites in developing countries. [Industrial Applicability]

[0051] The present invention relates to a method for recycling asphalt mixtures, and is a method that can be applied at asphalt pavement construction sites when recycling recycled asphalt that complies with standards from asphalt waste material that was used in existing asphalt pavement.

Claims

1. A test unit for analyzing the content of effective asphalt components in asphalt waste, The test unit comprises: A test vessel having a cylindrical shape with a bottom and a predetermined diameter; At least one test strip cut into a circle approximately equal to the inner diameter of the test container; A tamping rod for tamping the asphalt waste material from above a first test paper included in the at least one test paper, the tamping rod being placed on top of the asphalt waste material loaded in the test container; having The amount of the effective asphalt component contained in the asphalt waste material to be analyzed is identified by analyzing the occupied area ratio, which is the ratio of the area of ​​the pattern of the effective asphalt component attached to the at least one test paper from the asphalt waste material compacted using the tamping rod to the total area of ​​the at least one test paper. A first table showing the relationship between the occupied area ratio of a plurality of types of samples of the waste asphalt material and the amount of the effective asphalt component contained in the samples; and a second table showing the relationship between the amount of the effective asphalt component contained in the sample and the amount of additive required to make up for the deficiency of the effective asphalt component; The amount of the effective asphalt component of the asphalt waste material to be analyzed is specified from the occupied area ratio of the asphalt waste material and the first table, A test unit characterized in that the amount of the additive required to make up for the deficiency of the effective asphalt component of the asphalt waste being analyzed is determined from the amount of the effective asphalt component identified in the asphalt waste and the second table.

2. A test unit for analyzing the content of effective asphalt components in asphalt waste, comprising: The test unit comprises: A test vessel having a cylindrical shape with a bottom and a predetermined diameter; At least one test strip cut into a circle approximately equal to the inner diameter of the test container; A tamping rod for tamping the asphalt waste material from above a first test paper included in the at least one test paper, the tamping rod being placed on top of the asphalt waste material loaded in the test container; having The amount of the effective asphalt component contained in the asphalt waste material to be analyzed is identified by analyzing the occupied area ratio, which is the ratio of the area of ​​the pattern of the effective asphalt component attached to the at least one test paper from the asphalt waste material compacted using the tamping rod to the total area of ​​the at least one test paper. Further comprising an image showing the at least one test paper having the effective asphalt component of the waste asphalt sample attached thereto; A test unit characterized in that the amount of additive required to make up for the deficiency of the effective asphalt components in the asphalt waste material being analyzed is determined by comparing the appearance of the at least one test paper to which the effective asphalt components are attached from the asphalt waste material being analyzed with the appearance of the at least one test paper shown in the image.

3. The image is composed of a plurality of images each showing the at least one test paper having the effective asphalt component of the sample of the plurality of types of the waste asphalt material attached thereto, The test unit according to claim 2, characterized in that the occupied area ratio of the pattern of the effective asphalt component attached to the at least one test paper, which is shown in each of the multiple images, varies in stages.

4. Further comprising a list; The test unit described in claim 3, characterized in that the list is created by matching a plurality of images in which the occupied area ratio of the pattern of the effective asphalt component is gradually different with the amount of the additive required to make up for the deficiency of the effective asphalt component in the samples of the plurality of types of asphalt waste material represented by each of the plurality of images.

5. 5. A test unit according to any one of claims 2 to 4, wherein the image is a digital image and is stored on a mobile device having a display capable of displaying the digital image.

6. A test unit according to any one of claims 2 to 4, characterized in that the image is a printed image.

Images