Method of removing asphalt pavement

Abstract

To provide a method for removing an asphalt pavement body, which reduces noise, which can be applied to both a steel floor slab and a concrete floor slab, and which reduces damage to the floor slab.SOLUTION: In a groove forming process, a cut groove 6 is formed in an asphalt pavement body 1 on a floor slab. In a heating process, a heating object area A inside the cutting groove 6 is heated in three stages by a road heater. In a first stage, a first heating-performing process and a first curing-performing process are repeated until the surface temperature of the floor slab reaches a first reference temperature. In a second stage, the second heating-performing step and the second curing-performing step are repeated until the surface temperature of the floor slab reaches a second reference temperature. At a third stage, the third heating-performing step and the third curing-performing step are repeated until the surface temperature of the deck reaches a third reference temperature. The heating-performing step and the curing-performing step are performed by sequentially heating the first to third blocks A1, A2, and A3 in the region A to be heated. The softened part of the asphalt pavement body 1 in the heating process is manually removed in a manual removing process.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a method for removing asphalt pavement, and more particularly to a method for removing asphalt pavement installed on a deck. [Background technology]

[0002] The chipping method is often used to remove asphalt pavement from roads, etc. In this method, a concrete breaker held and operated by a worker impacts the asphalt pavement to break it up. The crushed pieces of the asphalt pavement are then transported from the site and the asphalt pavement is removed.

[0003] However, the chipping method has the problem of generating loud noises exceeding 90 dB when the asphalt pavement is broken up with a concrete breaker. Therefore, it is difficult to adopt the chipping method in densely populated residential areas or near hospitals or schools, where environmental conservation is particularly important.

[0004] Meanwhile, a method using an electromagnetic induction heating device has been proposed as a low-noise method for removing asphalt pavement (see, for example, Patent Document 1). In this asphalt pavement removal method, an electromagnetic induction coil is installed above the asphalt pavement placed on the steel plate of a steel deck, and the temperature of the steel plate is raised by the electromagnetic induction effect of this electromagnetic induction coil. At this time, the steel plate is heated so that the lower part of the asphalt pavement is heated to 80°C or higher. This softens the lower part of the asphalt pavement in contact with the steel plate, causing the asphalt pavement to peel off from the steel plate. The asphalt pavement that has peeled off from the steel plate is then cut up using heavy machinery and removed from the deck. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-291839 Summary of the Invention [Problem to be solved by the invention]

[0006] However, asphalt pavement removal methods using electromagnetic induction heating equipment require the presence of steel plates for induction heating, so they cannot be applied to asphalt pavement on concrete decks. Furthermore, asphalt pavement removal methods using electromagnetic induction heating equipment heat the steel plates so that the bottom of the asphalt pavement reaches 80°C or higher, the temperature of the steel plates exceeds 100°C. This temperature rise in the steel plates may cause deterioration of the paint applied to the backside of the steel plates of the steel deck.

[0007] Therefore, an object of the present invention is to provide a method for removing asphalt pavement that is quiet, applicable to both steel and concrete decks, and causes little damage to the decks. [Means for solving the problem]

[0008] In order to solve the above problems, the asphalt pavement removal method of the present invention is a method for removing an asphalt pavement laid on a deck, a heating step of heating the asphalt pavement using a road heater; and a manual removal process in which the softened portions of the asphalt pavement caused by the heating process are manually removed. The heating step is a first stage in which a first heating execution step of heating for a first heating time at a first heating intensity and a first curing execution step of covering the area heated in the first heating execution step with a heat insulating sheet and curing for a first curing time are repeated until the surface temperature of the deck reaches a first reference temperature; a second stage in which a second heating execution step of heating at a second heating intensity for a second heating time shorter than the first heating time and a second curing execution step of covering the area heated in the second heating execution step with a heat insulating sheet and curing for a second curing time shorter than the first curing time are repeated until the temperature of the surface of the deck reaches a second reference temperature; a third stage in which a third heating execution step is performed in which heating is performed at a third heating intensity that is equal to or lower than the first and second heating intensities for a third heating time that is shorter than the second heating time, and a third curing execution step is performed in which the area heated in the third heating execution step is covered with a heat insulating sheet and cured for a third curing time that is shorter than the second curing time, until the temperature of the surface of the deck reaches a third reference temperature; Including, The first reference temperature is 30°C or higher and lower than 40°C, the second reference temperature is 40°C or higher and lower than 50°C, and the third reference temperature is 50°C or higher and lower than 60°C.

[0009] According to the above configuration, in the heating step, the asphalt pavement laid on the deck is heated by a road heater. Any known road heater capable of heating asphalt pavement can be used. This heating step includes first to third steps. In the first step, a first heating step is performed for a first heating time at a first heating intensity, and a first curing step is performed for a first curing time by covering the area heated in the first heating step with a heat-shielding sheet. These steps are repeated until the surface temperature of the deck reaches a first reference temperature of 30°C or higher but lower than 40°C. Here, the first heating step and the first curing step are repeated one or more times. In the second stage, a second heating execution step of heating at a second heating intensity for a second heating time shorter than the first heating time, and a second curing execution step of covering the area heated in the second heating execution step with a heat-shielding sheet and curing for a second curing time shorter than the first curing time, are repeated until the temperature of the surface of the deck reaches a second reference temperature of 40°C or higher and less than 50°C. Here, the second heating execution step and the second curing execution step are repeated one or more times. In the third stage, a third heating execution step of heating at a third heating intensity lower than the first and second heating intensities for a third heating time shorter than the second heating time, and a third curing execution step of covering the area heated in the third heating execution step with a heat-shielding sheet and curing for a third curing time shorter than the second curing time, are repeated until the temperature of the surface of the deck reaches a third reference temperature of 50°C or higher and less than 60°C. Here, the third heating execution step and the third drying execution step are repeated one or more times. By performing steps one through three in this manner, the temperature of the asphalt pavement can be raised uniformly without excessively increasing the surface temperature of the asphalt pavement, thereby softening the entire heated area of ​​the asphalt pavement. This makes it possible to manually remove the softened portion of the asphalt pavement in the heating step in the manual removal step. Therefore, the asphalt pavement can be removed with less noise than conventional chipping methods using concrete breakers. Furthermore, because the maximum temperature reached by the deck surface in the heating step is between 50°C and 60°C, which is the third reference temperature, thermal damage to the deck can be effectively prevented.Furthermore, the asphalt pavement removal method of the present invention uses a known road heater to heat the asphalt pavement, and is therefore applicable to asphalt pavement laid on either a steel deck or a concrete deck. Here, the heating process may include other steps for heating the asphalt pavement in addition to the first to third steps.

[0010] In one embodiment, the asphalt pavement removal method includes, prior to the heating step, a groove forming step of forming a grid-shaped cut groove in the asphalt pavement so as to surround the area to be heated in the heating step.

[0011] According to the above embodiment, in the groove formation process prior to the heating process, grid-shaped cutting grooves are formed in the asphalt pavement so as to surround the area to be heated in the heating process. In the area where this grid-shaped cutting groove overlaps with the area to be heated in the heating process, heat can be effectively transferred through the cutting groove to the inside of the asphalt pavement. Therefore, the heating efficiency of the asphalt pavement in the area to be heated can be effectively improved. Furthermore, because the grid-shaped cutting grooves are formed so as to surround the area to be heated in a plan view, the heat applied to the area to be heated is confined to the inside of the outer edge of the cutting groove, preventing heat transfer to the outside of the cutting groove. Therefore, the effects of heat on the outer portion of the cutting groove, which is the portion of the asphalt pavement to be left, can be effectively prevented.

[0012] In one embodiment of the asphalt pavement removal method, the heating step divides the area of ​​the asphalt pavement to be heated into a plurality of blocks, and heats these blocks in sequence, thereby performing the heating step and the curing step on each block.

[0013] According to the above embodiment, in the heating step, the heating target area of ​​the asphalt pavement is divided into multiple blocks, and these multiple blocks are heated in sequence. For example, if the heating target area of ​​the asphalt pavement is divided into three blocks, in the first stage, the first block is heated in the first heating execution step. After this, the second block and the third block are each heated in sequence in the first heating execution step. When the first heating execution step is performed on these second block and third block, the first curing execution step can be performed in parallel on the first block. In this way, by dividing the heating target area of ​​the asphalt pavement into multiple blocks and heating them in sequence, the heating execution step and curing execution step can be performed efficiently. Note that the number of blocks into which the heating target area is divided is not limited to three, and may be any number of blocks, such as two, four, or more.

[0014] In one embodiment, the method for removing an asphalt pavement includes a ripper removal process in which a portion of the asphalt pavement inside the cutting groove that was not removed in the manual removal process is removed using a ripper.

[0015] According to the above embodiment, in the ripper removal process, the portion of the inside of the cut groove of the asphalt pavement that was not removed in the manual removal process is removed using a ripper. The portion that was not removed in the manual removal process corresponds to the portion between the portion that was heated and softened in the heating process and the outer edge of the cut groove. Because this portion is relatively small, it can be easily separated from the deck slab and other portions of the asphalt pavement using a ripper. Here, the ripper is attached to heavy machinery, and the noise generated when working with a ripper attached to heavy machinery is smaller than the noise generated in chipping methods that use concrete breakers, thereby reducing the impact on the surrounding environment.

[0016] In one embodiment of the asphalt pavement removal method, the first to third heating intensities in the heating step are intensities that cause the surface temperature of the asphalt pavement to be 340° C. or lower.

[0017] According to the above embodiment, the first to third heating intensities in the heating step are set to intensities that will cause the surface temperature of the asphalt pavement to be 340°C or less, thereby effectively preventing the asphalt pavement from emitting smoke or fire, and ultimately preventing the generation of unpleasant odors due to smoke or fire. Therefore, even in densely populated residential areas or near hospitals or schools, asphalt pavement removal can be carried out while preserving the environment. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is a cross-sectional view showing a pavement to which a method for removing an asphalt pavement according to an embodiment of the present invention is applied. [Figure 2] FIG. 2 is a plan view showing the cutting grooves formed in the asphalt pavement during the groove forming process and the area to be heated. [Figure 3] FIG. 10 is a schematic diagram showing a state in which a heating step is performed. [Figure 4A] FIG. 10 is a diagram showing how a first block of a heating target area is heated in a heating step. [Figure 4B] 10 is a diagram showing how the second block in the heating target area is heated and the first block is cured in the heating step. FIG. [Figure 4C] 10 is a diagram showing how the third block in the heating target area is heated and the first and second blocks are cured in the heating step. FIG. [Figure 5] This is a cross-sectional view showing how the inner portion of the cut groove of the asphalt pavement is removed during the ripper removal process. DETAILED DESCRIPTION OF THE INVENTION

[0019] The present invention will be described in detail below with reference to the illustrated embodiments.

[0020] FIG. 1 is a cross-sectional view showing an asphalt pavement to be removed by the asphalt pavement removal method of this embodiment. This asphalt pavement 1 is laid on top of a concrete slab 5 of an elevated road. Asphalt pavement 1 has a base layer 2 formed of dense-grained asphalt on top of the concrete slab 5, and a surface layer 3 formed of dense-grained gap asphalt on top of this base layer 2. The concrete slab 5 and base layer 2, and the base layer 2 and surface layer 3 are sealed together with a tack coat (not shown). The elevated road comprising this asphalt pavement 1 and slab 5, is adjacent to a densely populated residential area, and environmental conservation measures such as noise and odor prevention must be taken into consideration when carrying out work to remove the asphalt pavement 1.

[0021] The asphalt pavement removal method of this embodiment includes a groove forming process in which grid-shaped cutting grooves are formed in the asphalt pavement, a heating process in which the asphalt pavement is heated with a road heater, a manual removal process in which the softened portions of the asphalt pavement are removed by hand, and a ripper removal process in which the remaining portions not removed in the manual removal process are removed with a ripper.

[0022] (Groove formation process) First, in this embodiment, a groove forming process is performed to form grid-shaped cut grooves in the area to be removed from the asphalt pavement. FIG. 2 is a plan view schematically showing the cut grooves 6 formed in the asphalt pavement 1 in the groove forming process and the heating target area A set inside the cut grooves 6. Prior to the groove forming process, core drilling is performed to install thermocouples for measuring the temperature of the concrete slab 5 within the heating target area A. The thickness of the asphalt pavement 1 is also measured based on the cores obtained by core drilling. As shown in FIG. 2, core cutting lines 9 formed by core drilling can be formed in the first block A1 of the heating target area A. Core drilling may also be performed at other locations.

[0023] In the groove forming process, a grid-shaped cut groove 6 is formed in the asphalt pavement 1 using an asphalt cutter driven by a motor or engine. The cut groove 6 is composed of a rectangular outer edge portion 7 and a grid portion 8 that partitions the inside of this outer edge portion 7. In this embodiment, the inside of the outer edge portion 7 is divided into nine portions by the grid portions 8, but the number of grid portions 8 that partition the inside of the outer edge portion 7 can be any number. In this embodiment, the cut grooves are formed along the boundaries between the first block A1, the second block A2, and the third block A3 of the heating target area A, and so as to divide each of the blocks A1 to A3 into three vertically as shown in FIG. 2.

[0024] The heating target area A is set inside the removal target area defined by the outer edge 7 of the cutting groove 6. In other words, the outer edge 7 of the cutting groove 6 is formed outside the heating target area A. In this embodiment, the outer edge 7 of the cutting groove 6 is formed 5 cm outside the outer periphery of the heating target area A. The heating target area A is set based on the heating area of ​​the load heater, and in this embodiment, the heating target area A is set to an area equivalent to three times the heating area of ​​the load heater. Each of the first to third blocks A1 to A3 of the heating target area A has an area substantially the same as the heating area of ​​the load heater.

[0025] The width of the cutting groove 6 formed in the groove forming process can be set between 3 mm and 20 mm depending on the width of the cutting blade of the asphalt cutter. Here, it is preferable to use a width of 5 mm for the cutting groove 6, which corresponds to the widely used cutting blade. The depth of the cutting groove 6 is preferably set several mm above the underside of the base layer 2 to prevent damage to the concrete slab 5.

[0026] By forming cutting grooves 6 in the asphalt pavement 1, heat can be effectively transferred into the asphalt pavement 1 through the lattice portion 8 in the area where the lattice portion 8 of the cutting groove 6 overlaps with the heating target area A. This effectively improves the heating efficiency of the asphalt pavement 1 in the heating target area A. In addition, because the outer edge portion 7 of the cutting groove 6 is formed 5 cm outside the periphery of the heating target area A, it is possible to block the transfer of heat to the outside of the outer edge portion 7 when heating the heating target area A in the heating process. This effectively prevents the heat from affecting the remaining portions of the asphalt pavement 1.

[0027] After forming the cutting grooves 6 in the asphalt pavement 1, a thermocouple is installed at the bottom of the core hole previously created within the heating target area A to measure the surface temperature of the concrete slab 5. Note that other temperature sensors may be used to measure the surface temperature of the concrete slab 5. Based on the surface temperature of the concrete slab 5 measured by this thermocouple, the settings of the first to third heating intensities of the heating process described below, the number of cycles of the first heating execution process and the first curing execution process in the first stage of the heating process, the number of cycles of the second heating execution process and the second curing execution process in the second stage, the number of cycles of the third heating execution process and the third curing execution process in the third stage, etc. are determined.

[0028] FIG. 3 is a schematic diagram showing the heating process of this embodiment, in which an asphalt pavement 1 on a concrete slab 5 is heated by a road heater 11. The road heater 11 is arranged opposite the asphalt pavement 1 and includes multiple infrared heaters 12 that heat the asphalt pavement 1 by burning propane gas as fuel; a gas cylinder 13 that supplies the propane gas; wheels 14, 15 at one end and the other end in the traveling direction; and a handle 16 at the other end in the traveling direction. The infrared heater 12 includes a fuel nozzle that sprays fuel and an infrared generator formed of a metal mesh, ceramic plate, or the like that burns the fuel sprayed by the fuel nozzle to generate infrared rays. The infrared heaters 12 have a roughly rectangular parallelepiped shape extending in the traveling direction, and multiple infrared heaters 12 are arranged widthwise. The heating intensity of the road heater 11 is set by adjusting the fuel supply pressure to the infrared heaters 12. The handle 16 is gripped and operated by an operator when moving the road heater 11. Because this road heater 11 is relatively lightweight, it can be operated and moved manually, and can be easily carried in and out. Furthermore, the heating process and curing process described below can be easily repeated. The RH-900 manufactured by Hanta Machinery Co., Ltd. can be used as this road heater 11.

[0029] (Heating process) In the heating step of this embodiment, the road heater 11 is used to carry out steps from the first stage to the third stage, and the asphalt pavement 1 is heated and softened.

[0030] (First Stage) FIG. 4A is a plan view showing the first heating step in which the first block of the heating target area A is heated by a road heater 11 during the first stage of the heating process. After forming the cut grooves 6 in the asphalt pavement 1 and before the heating step, a frame-shaped heat-shielding sheet 20 is placed around the heating target area A to prevent the surrounding area from being affected by heat during the heating step. The first stage of the heating process involves a first heating step in which heating is performed for a first heating time at a first heating intensity, and a first curing step in which the area heated in the first heating step is covered with a heat-shielding sheet and cured for a first curing time, repeated until the surface temperature of the concrete slab 5 reaches a first reference temperature. The first reference temperature is set between 30°C and 40°C, depending on the temperature of the concrete slab 5 at the start of heating. For example, if the surface temperature of the concrete slab 5 is about 10°C in winter, the first reference temperature is set to about 30°C, and if the surface temperature of the concrete slab 5 is about 30°C in summer, the first reference temperature is set to about 39°C.

[0031] The first stage of the heating process is the initial stage of heating the asphalt pavement 1, and the first heating intensity of the first heating execution process is adjusted appropriately depending on the surface temperature of the asphalt pavement 1 at the start of heating. Also, because the temperature of the asphalt pavement 1 is the lowest during the heating process, the first heating time of the first heating execution process is ensured to be longer than the second and third heating times of the second and third stages described below. In the first curing execution process, the area heated in the first heating execution process is covered with a heat-shielding sheet and cured, thereby diffusing heat in the depth direction of the asphalt pavement 1 and making the temperature uniform throughout the depth direction. The first curing time is set longer than the first heating time.

[0032] 4B is a plan view showing the first curing step performed in the first block A1 of the heating target area A and the first heating step performed in the second block A2 during the first stage of the heating step. As shown in FIG. 4B, a rectangular heat shield sheet 22 is placed on the first block A1 of the heating target area A, and the first block A1 is cured. This curing diffuses the heat applied in the first heating step in FIG. 4A in the depth direction of the first block A1 of the heating target area A. Also, as shown in FIG. 4B, the load heater 11 is moved from the first block A1 of the heating target area A to the second block A2, and the heating step is performed in the second block A2 using the same first heating intensity and first heating time as in the first block A1.

[0033] 4C is a plan view showing the first curing process being performed in the first block A1 and the second block A2 of the heating target area A, and the first heating process being performed in the third block A3, during the first stage of the heating process. As shown in FIG. 4C, the first block A1 of the heating target area A continues to be cured from FIG. 4B. In the second block A2, a rectangular heat shield sheet 22 is placed and cured. In addition, the load heater 11 is moved from the second block A2 to the third block A3, and in the third block A3, a heating process is performed using the same first heating intensity and first heating time as in the first block A1.

[0034] 4A to 4C, the first curing execution step and the first curing execution step are performed block by block in the first block A1 to third block A3 of the heating target area A. In the first block A1 to third block A3, the cycle of the first heating execution step and the first curing execution step is repeated while measuring the surface temperature of the concrete floor slab 5. When the surface temperature of the concrete floor slab 5 reaches the first reference temperature, the cycle of the first heating execution step and the first curing execution step is ended, and the first stage is completed.

[0035] (Phase 2) In the second stage of the heating process, a second heating execution process is performed in which heating is performed for a second heating time at a second heating intensity, and a second curing execution process is performed in which the area heated in the second heating execution process is covered with a heat-shielding sheet and cured for a second curing time, and these processes are repeated until the surface temperature of the concrete slab 5 reaches a second reference temperature. The second reference temperature is equal to or higher than 40°C and lower than 50°C, and is set according to the first reference temperature.

[0036] The second heating intensity is set based on the difference between the first and second reference temperatures, the air temperature, etc. The second heating time is set to be shorter than the first heating time. Also, the second curing time is set to be shorter than the first curing time.

[0037] In the second stage of the heating process, the second heating intensity, the second heating time, and the second curing time are set, and similarly to the first stage, a cycle of the second heating execution process and the second curing execution process is repeated for the first block A1 to the third block A3 of the heating target area A while measuring the surface temperature of the concrete slab 5. In the second stage, the road heater 11 is moved from the first block A1 to the third block A3, and the second heating execution process and the second curing execution process are performed sequentially, as shown in Figures 4A to 4C. When the surface temperature of the concrete slab 5 reaches the second reference temperature, the cycle of the second heating execution process and the second curing execution process ends, and the second stage ends.

[0038] (Third Stage) In the third stage of the heating process, a third heating execution process is performed in which heating is performed for a third heating time at a third heating intensity, and a third curing execution process is performed in which the area heated in this third heating execution process is covered with a heat-shielding sheet and cured for a third curing time, and these steps are repeated until the surface temperature of the concrete slab 5 reaches a third reference temperature. The third reference temperature is equal to or higher than 50°C and lower than 60°C, and is set according to the second reference temperature.

[0039] The third heating intensity is set to be equal to or lower than the first heating intensity and the second heating intensity. The third heating time is set to be shorter than the second heating time. Furthermore, the third curing time is set to be shorter than the second curing time.

[0040] In the third stage of the heating process, the third heating intensity, the third heating time, and the third curing time are set, and similarly to the first stage, a cycle of the third heating execution process and the third curing execution process is repeated for the first block A1 to the third block A3 of the heating target area A while measuring the surface temperature of the concrete slab 5. In the third stage, the road heater 11 is moved from the first block A1 to the third block A3, and the third heating execution process and the third curing execution process are performed sequentially, as shown in Figures 4A to 4C. When the surface temperature of the concrete slab 5 reaches the third reference temperature, the cycle of the third heating execution process and the third curing execution process ends, and the third stage ends.

[0041] In the first to third stages of the heating process, the first to third heating intensities by the road heater 11 are set to intensities that will bring the surface temperature of the asphalt pavement 1 to 340°C or less. This effectively prevents the asphalt pavement 1 from emitting smoke or catching fire, and ultimately prevents the generation of unpleasant odors due to smoke or fire.

[0042] According to the heating process of this embodiment, by carrying out the first to third stages, heating can be performed so that the temperature of the asphalt pavement 1 is substantially uniform in the depth direction. Therefore, the asphalt pavement 1 can be softened uniformly. Furthermore, since the surface temperature of the concrete slab 5 when heating the asphalt pavement 1 can be kept below 60°C, deterioration of the concrete slab 5 can be effectively prevented.

[0043] (Manual removal process) After heating the asphalt pavement 1 in the heating process, a manual removal process is carried out to manually remove the softened portions of the asphalt pavement 1. Specifically, for the heating target area A that was softened by heating the asphalt pavement 1 in the heating process, workers manually remove the softened asphalt of the base layer 2 and surface layer 3 using a shovel or the like. This manual removal process does not use a concrete breaker, so the asphalt pavement 1 can be removed with less noise than conventional chipping methods.

[0044] (Ripper removal process) After the heating target area A of the asphalt pavement 1 is removed in the manual removal process, the remaining portion that was not removed in this manual removal process is removed in the ripper removal process. Specifically, the portion between the outer periphery of the heating target area A of the asphalt pavement 1 and the outer edge 7 of the cut groove 6 is not softened and remains unremoved in the manual removal process. This portion is removed using a ripper attached to heavy machinery. Figure 5 is a cross-sectional view schematically showing the removal of the portion remaining inside the outer edge 7 of the cut groove 6 formed in the asphalt pavement 1 using a ripper 25. The portion to be removed in the ripper removal process is the portion between the outer periphery of the heating target area A of the asphalt pavement 1 and the outer edge 7 of the cut groove 6. This portion is substantially separated from the outer portion of the cut groove 6 of the asphalt pavement 1 by the outer edge 7, and its bottom surface is only adhered to the concrete slab 5 by a tack coat. Therefore, by inserting the tip of the ripper 25 between the asphalt pavement 1 and the concrete slab 5 and lifting it up, the target portion can be relatively easily detached from the concrete slab 5 and the portion outside the outer edge 7 of the asphalt pavement 1, and broken down into relatively small pieces. The target portion thus detached from the concrete slab 5 and broken down is relatively small in volume, so it can be moved by hand to a transport cart or vehicle. Furthermore, the noise generated when working with the ripper 25 attached to heavy machinery is smaller than the noise generated by chipping methods that use concrete breakers, so the impact on the surrounding environment can be reduced.

[0045] The ripper removal process removes the remaining portion inside the outer edge 7 of the cutting groove 6 of the asphalt pavement 1, and then the pavement can be restored by placing an asphalt mixture or the like inside the outer edge 7 of the cutting groove 6.

[0046] According to the asphalt pavement removal method of this embodiment, the heating step and manual removal step make it possible to remove the asphalt pavement with little noise while preventing damage to the deck slab.

[0047] In the above embodiment, the asphalt pavement 1 had a base layer 2 made of dense-grained asphalt and a surface layer 3 made of dense-grained gap asphalt, but the present invention can also be applied to drainage pavements in which the surface layer is made of permeable asphalt.

[0048] Furthermore, while the above embodiment is directed to the asphalt pavement 1 installed on a concrete deck 5, the present invention can also be applied to asphalt pavement installed on a steel deck. When removing asphalt pavement on a steel deck, the present invention makes it possible to remove the asphalt pavement with little noise while preventing damage to the steel deck by suppressing the surface temperature of the steel deck to less than 60°C.

[0049] In addition, in the above embodiment, the heating target area A is divided into three blocks, from the first block A1 to the third block A3, but the number of blocks into which the heating target area is divided is not limited to three, and may be two or any number of blocks greater than four.

[0050] (Example) The asphalt pavement removal method of the above embodiment was carried out in Example 1 in the summer when the surface temperature of the concrete slab 5 was relatively high, and in Example 2 in the winter when the surface temperature of the concrete slab 5 was relatively low. The noise during construction and the feasibility of manual removal of the heating target area A of the asphalt pavement 1 were confirmed for these examples. Table 1 shows the conditions for the heating process in Examples 1 and 2, and Table 2 shows the results for Examples 1 and 2.

[0051] [Table 1]

[0052] [Table 2]

[0053] In Table 2, ◯ indicates that manual removal is possible. As shown in Table 2, in both Examples 1 and 2, the heating target area A of the asphalt pavement 1 softened, making it possible to remove it manually. In addition, the noise level was significantly lower than the 90 dB level achieved when a concrete breaker was used. Here, the noise levels in Examples 1 and 2 were all noise levels generated during the ripper removal process.

[0054] The present invention is not limited to the above-described embodiments, and many modifications can be made by a person having ordinary skill in the art within the technical concept of the present invention. [Explanation of symbols]

[0055] 1. Asphalt pavement 2 Base layer 3 Surface layer 5 Concrete deck 6 Cutting groove 7 Outer edge of cutting groove 8 Cutting groove lattice 9 Core cutting wire 11 Road Heater 12 Infrared heater 20,22 Heat-shielding sheet 25 Ripper A. Heating target area A1 First block of the heating area A2 Second block of the heating area A3 Third block of the heating area

Claims

1. An asphalt pavement removal method for removing an asphalt pavement laid on a deck, comprising: a heating step of heating the asphalt pavement using a road heater; and a manual removal process in which the softened portions of the asphalt pavement caused by the heating process are manually removed. The heating step is a first stage in which a first heating execution step of heating for a first heating time at a first heating intensity and a first curing execution step of covering the area heated in the first heating execution step with a heat insulating sheet and curing for a first curing time are repeated until the surface temperature of the deck reaches a first reference temperature; a second stage in which a second heating execution step of heating at a second heating intensity for a second heating time shorter than the first heating time and a second curing execution step of covering the area heated in the second heating execution step with a heat insulating sheet and curing for a second curing time shorter than the first curing time are repeated until the temperature of the surface of the deck reaches a second reference temperature; a third stage in which a third heating execution step is performed in which heating is performed at a third heating intensity equal to or lower than the first and second heating intensities for a third heating time shorter than the second heating time, and a third curing execution step is performed in which the area heated in the third heating execution step is covered with a heat insulating sheet and cured for a third curing time shorter than the second curing time, until the temperature of the surface of the deck reaches a third reference temperature; Including, A method for removing asphalt pavement, characterized in that the first reference temperature is 30°C or higher and lower than 40°C, the second reference temperature is 40°C or higher and lower than 50°C, and the third reference temperature is 50°C or higher and lower than 60°C.

2. The asphalt pavement removal method according to claim 1, An asphalt pavement removal method characterized by including, prior to the heating step, a groove forming step of forming a grid-shaped cutting groove so as to surround the area of ​​the asphalt pavement to be heated in the heating step.

3. The asphalt pavement removal method according to claim 1, A method for removing asphalt pavement, characterized in that the heating step divides the area of ​​the asphalt pavement to be heated into a plurality of blocks, and heats these blocks in sequence, thereby performing the heating execution step and the curing execution step on each block.

4. The asphalt pavement removal method according to claim 2, An asphalt pavement removal method characterized by comprising a ripper removal process for removing with a ripper any portion of the inside of the cut groove of the asphalt pavement that was not removed in the manual removal process.

5. The asphalt pavement removal method according to claim 1, A method for removing an asphalt pavement, characterized in that the first to third heating intensities in the heating steps are intensities that result in a surface temperature of the asphalt pavement of 340°C or less.

Images