JP2017042715A - Construction method for waste disposal site - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a construction method for a waste disposal site which enables an earlier start of the service of the waste disposal site.SOLUTION: A construction method for a waste disposal site, which is a construction method for a waste disposal site for constructing a waste disposal site in a predetermined region X, comprises a first ground improvement step of improving the ground of a partial region X1 of the predetermined region X, a first water-shielding step of providing a water-shielding part 3 in the surface of the ground G1 of the region X1, a first protective layer establishment step of providing a protective layer 6 in the surface of the water-shielding part 3 of the region X1, a first dam installation step of providing a dam 7 in the surface of the ground G1 of the boundary part Y1 of the region X1, a second ground improvement step of improving the ground of another region adjacent to the boundary part Y1 of the region X, a second water-shielding step of providing a water-shielding part 13 in the surface of the ground G2 of a region X2, a second protective layer establishment step of providing a protective layer 16 in the surface of the water-shielding part 13 of the region X2, a second dam installation step of providing the dam 17 in the boundary part Y2 different from the region X1 side in the region X2.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a method for constructing a waste disposal site.

  Conventionally, in order to prevent various harmful substances leaching from the waste from penetrating into the ground and causing groundwater contamination and ground contamination, wastewater disposal sites have been provided with water shielding sheets on the ground. In addition, waste is deposited thereon (see Patent Document 1 below).

  Also, when constructing a waste disposal site on flat ground, excavate the ground and lay a waterproof sheet on the surface of the ground. Then, a protective layer such as sand is provided on the water shielding sheet so that the waste does not directly contact the water shielding sheet and cause damage to the water shielding sheet, and the waste is carried thereon. On the other hand, when constructing a waste disposal site in the valley, after excavating the slope, a water shielding sheet is laid and a protective layer is provided thereon, as in the case of flat land.

  When the ground is soft, the ground may sink unevenly due to the weight of the waste, or a local tensile stress may be generated in the waterproof sheet and the waterproof sheet may be broken. Therefore, when the ground is soft, it is necessary to improve the ground and stabilize the ground.

  In addition, a water collecting pipe that collects leachate leached from the waste is laid on a water shielding sheet, and water is treated with a wastewater treatment facility installed on the downstream side to remove harmful substances and drain the water.

Japanese Patent No. 5666742

  As mentioned above, in order to construct a waste disposal site, it is necessary to carry out construction work such as ground improvement, installation of water shielding sheets, water collection pipes and protective layers, and construction of wastewater treatment facilities. It was prolonged. Furthermore, if the waste disposal site was large, the construction period was even longer. For this reason, there is a problem that waste cannot be disposed of promptly.

  Then, this invention is made | formed in view of the said situation, and provides the construction method of the waste disposal site which can start operation of a waste disposal site at an early stage.

In order to achieve the above object, the present invention employs the following means.
That is, a construction method of a waste disposal site according to the present invention is a construction method of a waste disposal site that constructs a waste disposal site in a predetermined area, and is a method for improving the ground of a part of the predetermined area. One ground improvement step, a first water shielding step for providing a water shielding portion on the surface of the ground in the partial area, and a first protective layer formation for providing a protective layer on the surface of the water shielding portion in the partial region A first dam installation step of providing a dam at a boundary portion of the partial region, a second ground improvement step of improving the ground of another region adjacent to the boundary portion of the predetermined region, and the other A second water shielding step for providing a water shielding portion on the surface of the ground in the region, a second protective layer forming step for providing a protective layer on the surface of the water shielding portion in the other region, and the part in the other region. A second dam installation step of providing a dam at a boundary portion different from the region side of To.

  In the construction method of the waste disposal site constructed in this way, in some areas of the predetermined area where the waste disposal site is constructed, a first ground improvement process for improving the ground, and a water shielding portion on the surface of the ground. If you implement the first water-blocking step, the first protective layer-setting step that provides a protective layer on the surface of the water-blocking portion, and the first dam-setting step that provides a dam at the boundary, A waste disposal site can be started in advance. In addition, while starting operation of the waste disposal site in some areas, the second ground improvement process for improving the ground in other areas, the second water shielding process for providing a water shielding part on the surface of the ground, and the water shielding part If the second protective layer installation process for providing a protective layer on the surface of the material and the second dam installation process for providing a dam at the boundary part different from the part of the area side are implemented, The service can be started. In other words, since some of the predetermined areas where waste disposal sites will be installed in the future can be started in advance of other areas, the operation of waste disposal sites can be started. Can be started early.

  In addition, the method for constructing a waste disposal site according to the present invention includes a first water collection pipe installation step in which a water collection pipe is installed in the partial area and connected to a water treatment facility, and a water collection pipe is installed in the other area. It is preferable to include a second water collecting pipe installing step, and a water collecting pipe connecting step for connecting the water collecting pipes in the partial area and the water collecting pipes in the other area.

  In the construction method of the waste disposal site configured in this way, the water collecting pipe is installed in a part of the area in the first water collecting pipe installation process and connected to the water treatment facility, and the other area in the second water collecting pipe installation process. In order to connect the water collection pipes in some areas to the water collection pipes in other areas in the water collection pipe connection process, the leachate flowing through the water collection pipes in other areas is The water can be collected by circulating it through a water collection pipe. Therefore, since it is not necessary to directly connect the water collection pipes in other areas to the water treatment facility side, large-scale construction is not involved.

  According to the construction method of the waste disposal site according to the present invention, the operation of the waste disposal site can be started at an early stage.

It is a typical top view which shows the structure of the land of the waste disposal site which concerns on one Embodiment of this invention. It is a figure for demonstrating the 1st ground improvement process of the construction method of the waste disposal site which concerns on one Embodiment of this invention. It is a figure for demonstrating the 1st water shielding process of the construction method of the waste disposal site which concerns on one Embodiment of this invention. It is a figure for demonstrating the 1st water collection pipe installation process of the construction method of the waste disposal site which concerns on one Embodiment of this invention, a water collection pipe connection process, a 1st protective layer creation process, and a 1st dam installation process. It is a figure for demonstrating the 2nd water-blocking process of the construction method of the waste disposal site which concerns on one Embodiment of this invention, the 2nd water collecting pipe installation process, the 2nd protective layer creation process, and the 2nd dam installation process. It is a figure for demonstrating the 1st ground improvement process of the construction method of the waste disposal site which concerns on the modification of one Embodiment of this invention. It is a figure for demonstrating the 1st water shielding process of the construction method of the waste disposal site which concerns on the modification of one Embodiment of this invention. It is a figure for demonstrating the 1st water collection pipe installation process, the 1st protective layer creation process, and the 1st dam installation process of the construction method of the waste disposal site which concerns on the modification of one Embodiment of this invention. The figure for demonstrating the 2nd water-blocking process of the construction method of the waste disposal site which concerns on the modification of one Embodiment of this invention, the 2nd water collecting pipe installation process, the 2nd protective layer creation process, and the 2nd dam installation process It is.

A construction method for a waste disposal site according to an embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a schematic plan view showing a configuration of land in a waste disposal site according to an embodiment of the present invention.
As shown in FIG. 1, in this embodiment, a waste disposal site is constructed on land (predetermined area) X on which a valley bottom A1 indicated by a two-dot chain line is formed. Along the slope A2 of the valley, the water discharge path P is cut in advance so as to surround the valley. The cut-off water discharge channel P is for preventing the water of the upstream inflowing river Q from entering the land X.

FIG. 2 is a diagram for explaining the first ground improvement process.
First, as shown in FIG. 2, a first ground improvement process for stabilizing the ground G <b> 1 is performed in a partial area X <b> 1 on the downstream side of the land X.

Next, a first water shielding step is performed.
FIG. 3 is a diagram for explaining the first water shielding step.
As shown in FIG. 3, the dam 1 and the water treatment facility 2 are installed on the downstream side of the region X1, and the water shielding sheet (water shielding portion) 3 is laid over the surface of the ground G1 in the region X1 improved from the dam 1 to the ground. To do. As the water shielding sheet 3, for example, a waterproof sheet made of a resin material such as a thermoplastic elastomer can be adopted. In addition, a water treatment facility 2 is installed on the downstream side of the dam 1, and a drain pipe 4 is installed between the dam 1 and the water treatment facility 2. In the water treatment facility 2, the leachate leached from the waste is introduced through a water collecting pipe 5 and the like which will be described later, and after purifying and removing harmful substances, it is discharged into a predetermined water area.

Next, a 1st water collection pipe installation process is performed.
Drawing 4 is a figure for explaining the 1st water collecting pipe installation process, the 1st protection layer creation process, and the 1st dam installation process.
As shown in FIG. 4, a water collecting pipe 5 made of a perforated pipe is installed along the valley bottom A <b> 1 of the region X <b> 1 and connected to the water drain pipe 4 connected to the water treatment facility 2.

Next, a first protective layer creation step is performed.
In the region X <b> 1, the protective layer 6 is provided on the water shielding sheet 3, and the water collecting pipe 5 is embedded in the protective layer 6. As the protective layer 6, a protective mat such as a nonwoven fabric or sand can be employed.

Next, the first dam installation process is performed.
A temporary dam (weir) 7 is installed at the boundary Y1 on the upstream side of the region X1, and a temporary dam sheet 8 is laid on at least the side surface 7A on the downstream side of the temporary dam 7. The temporary dam sheet 8 prevents toxic substances leached from the waste from leaching into the adjacent upstream region X2. At this time, the water collecting pipe 5 is passed through the temporary dam 7 and the upstream end 5X is sealed.
In addition, while performing the operation | work which provides the protective layer 6 in the area | region X1 from the downstream, the 1st protective layer formation process and the 1st dam installation process are progressing simultaneously so that the temporary dam 7 may be installed in the upstream of the area | region X1. You may go.
Thereby, in the area | region X1, waste (refer FIG. 5) W1 can be carried in.

Next, the same operation as that of the region X1 is performed in the region X2 upstream of the boundary portion Y1 of the region X1.
First, in the area X2, a second ground improvement process for improving the ground G2 is performed.

FIG. 5 is a diagram for explaining the second water shielding step, the second water collecting pipe installation step, the water collecting pipe connection step, the second protective layer creation step, and the second dam installation step.
Next, a second water shielding step is performed.
As shown in FIG. 5, the water shielding sheet 13 is installed on the surface of the ground G2 in the region X2, and the downstream end is connected to the water shielding sheet 3 installed in the region X1 by welding or the like.

  Next, the 2nd water collecting pipe installation process which installs the water collecting pipe 15 along the valley bottom A1 of the area | region X2 is performed. Then, the water collection pipe connection process which connects the water collection pipe 5 and the water collection pipe 15 which let the edge part of the downstream side penetrate the temporary dam 7 is performed.

  Next, in the region X <b> 2, a protective layer 16 is provided on the water-impervious sheet 13, and a second protective layer creation step is performed in which the water collecting pipe 15 is embedded in the protective layer 16.

Next, the second dam installation process is performed.
The temporary dam 17 is installed at the boundary Y2 on the upstream side of the region X2, and the temporary dam sheet 18 is laid on at least the side surface 17A on the downstream side of the temporary dam 17. The water collecting pipe 15 is passed through the temporary dam 17, and the upstream end 15X is sealed.
Thereby, in the area | region X2, a waste (not shown) can be carried in. Next, by repeating the same operation on the upstream side of the region X2, the operation of the waste disposal site can be started sequentially from the downstream region.

  In the construction method of the waste disposal site configured as described above, in the region X1 of the land X where the waste disposal site is constructed, the first ground improvement step for improving the ground G1, the surface of the ground G1 If the first water shielding step of providing the water shielding sheet 3, the first protective layer installation step of providing the protective layer 6 on the surface of the water shielding sheet 3, and the first dam installation step of providing the temporary dam 7 at the boundary Y <b> 1 are performed. In the area X1, the operation of the waste disposal site can be started in advance. In addition, while starting operation of the waste disposal site in the area X1, in the other area X2, a second ground improvement process for improving the ground G2, a second water shielding process for providing the water shielding sheet 13 on the surface of the ground G2, If the second protective layer installation step in which the protective layer 16 is provided on the surface of the water-impervious sheet 13 and the second dam installation step in which the temporary dam 17 is provided in the boundary portion Y2 different from the region X1 side are performed, the disposal in the region X2 The disposal site can be started. In other words, because it is possible to start the operation of the waste disposal site by putting the region X1 ahead of the region X2 in the X where the waste disposal site will be installed in the future, the operation of the waste disposal site is started early. can do.

  Moreover, the water collecting pipe 5 is installed in the area X1 in the first water collecting pipe installation process and connected to the water treatment facility 2 side, the water collecting pipe 15 is installed in the area X2 in the second water collecting pipe installation process, and the water collecting pipe connection process. Since the water collecting pipe 5 and the water collecting pipe 15 are connected, the leachate flowing through the water collecting pipe 15 in the region X2 can be circulated through the water collecting pipe 5 in the region X1 to collect water. Therefore, since it is not necessary to directly connect the water collecting pipe 15 of the other region X2 to the water treatment facility 2 side, large-scale construction is not involved.

  In addition, the waste disposal site will be used in some areas, but at the initial stage of construction, the water treatment facility 2 is installed on the most downstream side of the land X, and the leachate leached from the waste in each area It is not necessary to install a plurality of water treatment facilities 2 by introducing to the water treatment facility 2.

Next, as a modification of the above-described embodiment, a method for sequentially starting in-use of the waste disposal site from the upstream side will be described mainly with reference to FIGS.
In the following modified examples, the same members as those used in the above-described embodiment are denoted by the same reference numerals, and the description thereof is omitted.

FIG. 6 is a diagram for explaining the first ground improvement process.
First, as shown in FIG. 1, similarly to the embodiment shown above, after cutting and turning the drainage channel P in the land X, as shown in FIG. 6, the ground G <b> 11 is stabilized in the upstream region X <b> 11. Therefore, the first ground improvement process is performed.

FIG. 7 is a diagram for explaining the first water shielding step.
Next, a first water shielding step is performed.
As shown in FIG. 7, the dam 11 is installed on the upstream side of the region X11, and the water-impervious sheet 23 is laid from the dam 11 over the surface of the ground G11 in the region X11 improved in the ground. In addition, the water treatment facility 2 is installed on the most downstream side of the land X.

FIG. 8 is a diagram for explaining the first water collecting pipe installation step, the first protective layer creation step, and the first dam installation step.
Next, as shown in FIG. 8, the 1st water collection pipe installation process which installs the water collection pipe 25 along the valley bottom A1 of the area | region X11 is performed.

  Next, in the region X <b> 11, a first protective layer forming step is performed in which the protective layer 26 is provided on the water shielding sheet 23 and the water collecting pipe 25 is embedded in the protective layer 26.

Next, the first dam installation process is performed.
The temporary dam 27 is installed at the boundary Y11 on the downstream side of the region X11, and the temporary dam sheet 28 is laid on at least the upstream side surface 27A of the temporary dam 27. At this time, a pumping well (not shown; the same applies hereinafter) connected to the water collecting pipe 25 is installed in the temporary dam 27, and the water pumped from the pumping well is installed on the outer periphery of the land X (not shown). It is possible to introduce it into the water treatment facility 2 via the figure.
In addition, while performing the operation | work which provides the protective layer 26 in the area | region X11 from upstream, the 1st protective layer formation process and the 1st dam installation process are advanced simultaneously so that the temporary dam 27 may be installed in the downstream of the area | region X11. You may go.
Thereby, in the area | region X11, the waste W21 (refer FIG. 9) can be carried in.

Next, the same operation as that in the region X11 is performed in the region X12 on the downstream side of the boundary portion Y11 of the region X11.
First, in the region X12, a second ground improvement process for improving the ground G12 is performed.

Next, a second water shielding step is performed.
FIG. 9 is a diagram for explaining the second water shielding step, the second water collecting pipe installation step, the second protective layer creation step, and the second dam installation step.
As shown in FIG. 9, the water shielding sheet 33 is installed on the surface of the ground G12 in the region X12, and the upstream end is connected to the water shielding sheet 23 installed in the region X11 by welding or the like.

  Next, the 2nd water collection pipe installation process which installs the water collection pipe 35 along the valley bottom A1 of the area | region X12 is performed.

  Next, in the region X <b> 12, a protective layer 36 is provided on the water shielding sheet 33, and a second protective layer forming step is performed in which the water collecting pipe 35 is embedded in the protective layer 36.

Next, the second dam installation process is performed.
A temporary dam 37 is installed at the boundary Y12 on the downstream side of the region X12, and a temporary dam sheet 38 is laid on at least the upstream side surface 37A of the temporary dam 37. At this time, a pumping well (not shown; the same applies hereinafter) connected to the water collecting pipe 35 is installed in the temporary dam 37, and the water pumped out from the pumping well is installed on the outer periphery of the land X. It is made to be able to be introduced into the water treatment facility 2 via the route.
Thereby, in area | region X12, a waste (not shown) can be carried in. Next, by repeating the same operation on the downstream side of the region X12, the operation of the waste disposal site can be started sequentially from the upstream region.

  The various shapes and combinations of the constituent members shown in the above-described embodiments are merely examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

  For example, in the embodiment and the modification described above, the example of starting the operation of the waste disposal site from the downstream side or the upstream side of the land X has been described, but the present invention is not limited thereto. The location where the service is started can be selected as appropriate. For example, after starting operation from the midstream side of the land X toward the upstream (downstream) side, the service can be started from the midstream side toward the downstream (upstream) side. Good.

DESCRIPTION OF SYMBOLS 1,11 ... Dam 2 ... Water treatment facilities 3, 13, 23, 33 ... Water shielding sheet 4 ... Drain pipes 5, 15, 25, 35 ... Catch pipes 6, 16, 26, 36 ... Protective layers 7, 17, 27, 37 ... Temporary dam A1 ... Valley bottom A2 ... Slope G1, G2, G11, G12 Ground W1, W21 ... Waste Y1, ... Boundary X ... Land (predetermined area)
X1, X11 ... some areas X2, X12 ... other areas

Claims (2)

A waste disposal site construction method for constructing a waste disposal site in a predetermined area,
A first ground improvement step of improving the ground of a part of the predetermined area;
A first water shielding step of providing a water shielding portion on the surface of the ground in the partial area;
A first protective layer forming step of providing a protective layer on the surface of the water shielding portion in the partial area;
A first dam installation step of providing a dam at the boundary of the partial area;
A second ground improvement step of improving the ground of the other region adjacent to the boundary portion of the predetermined region;
A second water shielding step of providing a water shielding portion on the surface of the ground in the other region;
A second protective layer forming step of providing a protective layer on the surface of the water shielding portion in the other region;
And a second dam installation step of providing a dam at a boundary portion different from the partial region side in the other region. A first water collecting pipe installation step of installing a water collecting pipe in the partial area and connecting it to a water treatment facility;
A second water collecting pipe installation step of installing a water collecting pipe in the other area;
A method for constructing a waste disposal site, comprising: a water collecting pipe connecting step for connecting the water collecting pipes in the partial area and the water collecting pipes in the other area.

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