JPH1110105A - Seepage liner layer structure of final waste disposal facility or the like and its execution method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a safe sure seepage liner layer structure by a method wherein a final waste disposal facility or the like is built in a multi-seepage control liners structure of the seepage liner layer in which clay of bentonite or the like is mixed, the seepage liner layer with soil cement, and the seepage liner layer with a sheet in the order from the mostlower part. SOLUTION: In the case where a waste disposal facility is built, a multi-seepage control layers structure of a seepage liner layer 11 in which clay of bentonite or the like is mixed, the seepage liner layer 6 with soil cement, and the seepage liner layer 12 with a sheet in the order from the mostlower part. Then, when the seepage liner layer 11 in which clay is mixed is formed, at first a ground is excavated in a specific shape with a backhoe or the like to form an underground water drainage facility, good quality soil stocked preliminarily in a site is transported thereafter, which is laid evenly in about 20 cm thickness, then the bentonite is scattered with the backhoe, and evely laid in a uniform thickness by human power. Thereafter the good quality soil and the bentonite are mixed and stirred with a stabilizer. After mixing by stirring, the flat forming is executed with a bulldozer, and rolling is executed with a roller.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-blocking structure such as a final disposal site for waste and an artificial pond such as a reservoir, and a method of constructing the same.

[0002]

2. Description of the Related Art Garbage is an inevitable phenomenon in human life, and the amount of waste is increasing year by year due to the improvement of living standards and expansion of business activities.

[0003] Waste materials that become unnecessary due to household or business activities are collected and transported as waste by municipalities or licensed companies, and after volume reduction such as incineration, crushing, and compression are performed, and then disposed of. It is transported to the site and disposed of by landfill. In this way, the waste disposal site is a facility for the final disposal of waste generated by human activities without causing environmental problems, and safely returns the waste to the earth by landfill. It is a facility.

However, if the waste is landfilled as it is, there is a concern that harmful substances and the like contained in the waste will diffuse into the soil and cause environmental destruction. Every year, the technical standards are improved and strengthened by laws and regulations, and measures are taken to prevent environmental destruction.

[0005] As a measure for preventing such harmful substances from diffusing into the soil, a method of preventing water leakage by laying a water-repellent sheet has been adopted. Particularly, in a final waste disposal site, as shown in FIG. It has also been attempted to improve safety by laying a double water-shielding sheet 1 such as a sheet or a vinyl chloride sheet. In FIG. 6, reference numeral 2 denotes the original ground, 3 denotes a non-woven fabric superimposed on the water-shielding sheet 1, 4 denotes a drainage layer laid between the first water-shielding sheet 1 and the second water-shielding sheet 1 at the bottom, and 5 denotes a second layer. This is a protective soil on the no-water sheet 1.

[0006] In the example shown in the figure, a nonwoven fabric 3 is further laid on the second water-shielding sheet 1 at the slope portion. In addition,
The protective soil 5 is formed by compacting the normal soil that has been scattered to protect the first and second water-shielding sheets 1 by rolling or the like. Since it is difficult in some cases, it is provided around the bottom surface.

[0007]

The double water-blocking structure of such a final disposal site is a water-blocking structure in which a water-blocking sheet 1 made of synthetic rubber, vinyl chloride, or the like is double laid, and sharp waste is generated. It is also conceivable that the two impervious layers may be damaged simultaneously due to the same factor, such as chemicals contained in wastewater and waste, and there is a possibility that water containing harmful substances may diffuse into the environment.

[0008] In particular, if the air bleeding sheet 1 made of synthetic rubber is not properly evacuated from the sheet side, the water permeable sheet 1 may be swollen after construction. If a vinyl chloride sheet is used, the synthetic rubber sheet 1
It is inexpensive and excellent in economic efficiency, but is inferior in long-term stability in terms of material.

An object of the present invention is to eliminate the disadvantages of the prior art and to provide a safe and reliable water-blocking structure by forming a multiple water-blocking structure using a variety of different water-blocking materials. A water-blocking layer containing clay such as bentonite is formed first, and a water-blocking layer with soil cement is applied on top of it. This allows heavy equipment to enter safely, and harmful substances caused by bentonite It is an object of the present invention to provide a water-blocking structure such as a final waste disposal site that can also effectively use a removing function and a method of constructing the same.

[0010]

According to the present invention, in order to achieve the above-mentioned object, as a water-blocking layer structure of a waste disposal site or the like, a water-blocking layer mixed with clay such as bentonite and a soil cement are sequentially arranged from the bottom. The main point is that a multi-layer water-sealing layer structure consisting of a water-sealing layer with a sheet and a water-sealing layer with a sheet, and that the protective layer provided on the sheet-water-sealing layer be formed as a soil layer stabilized with soil cement. Is what you do.

[0011] As a method of constructing a water-blocking structure at a final waste disposal site or the like, an excavator is excavated into a predetermined shape, and bentonite is scattered and spread to a uniform thickness. Perform mixed stirring of bentonite, perform irregular shaping,
Rolling and forming a water blocking layer by bentonite, spread the locally generated soil on it to a predetermined thickness, spread it, and evenly spread a solidified material such as cement using a chemical sprayer, After spraying the solidified material, mix it using a mixer and spread it uniformly to a predetermined thickness and spread it.
Rolling is performed, and after rolling is completed, the surface is finished to form a soil-cemented water-blocking layer, and a nonwoven fabric and water-blocking sheet are laid on it to form a water-blocking layer with a sheet, and then a stable treatment is performed on it. The main point is to provide a soil layer.

According to the first and third aspects of the present invention, the water-blocking layer is formed of a water-blocking sheet made of synthetic rubber, soil cement, and bentonite. By adopting a multiple water-blocking structure using materials, the possibility that the water-blocking layer is simultaneously damaged by the same factor is extremely reduced, and a safer and more reliable water-blocking layer can be formed.

In particular, since a soil cement blocking layer and a blocking layer mixed with clay such as bentonite are arranged on the base portion, these can be used as a base of the blocking sheet to provide a stable ground without uneven settlement. In addition, most of the excavated soil can be used as soil mixed with clay such as soil cement aquifer or bentonite, so the amount of residual soil disposal can be reduced, which is economical and environmentally friendly. Can be reduced.

[0014] Further, by forming the water blocking layer by soil cement, it is possible to form the ground having a supporting force enough to withstand the load of landfill waste, landfill work heavy equipment and the like. In addition, montmorillonite contained in bentonite swells when it comes in contact with water to stop water. Therefore, in terms of quality, even if it is repeatedly subjected to the dry and wet action due to the fluctuation of the water level, the swelling action is repeated each time and the stability is maintained for a long period of time, and it is possible to follow the deformation due to the uneven settlement of the ground.

According to the second aspect of the present invention, in addition to the above-mentioned effects, since the soil-cement-stabilized soil layer has a certain level of strength, it is possible to prevent heavy machinery from damaging the water-repellent sheet during landfill work. Can be prevented. In addition, the soil cement stabilization soil layer mitigates the weather factors and reduces the influence on the water-shielding sheet, preventing deterioration of the water-shielding sheet due to heat, light, ozone, etc. The expansion and contraction of the water shielding sheet can be reduced. Furthermore, since the soil cement stabilization treatment layer plays a role of weight, it is possible to omit the fixing work of the moisturizing sheet at the small step of the slope, and protect the entire moisturizing sheet with the stabilized soil at the time of constructing the disposal site. Therefore, there is no need to apply protective soil to the damping sheet on the slope at the time of landfill.

[0016]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a vertical side view of a final waste disposal site having a water blocking structure according to the present invention, FIG. 2 is a vertical side view of a bottom portion of the same, and FIG. 3 is a vertical side view of a slope portion. A water-blocking layer 11 containing clay such as bentonite, a water-blocking layer 6 made of soil cement, and a water-blocking layer 12 made of sheet were formed in order from the bottom.

Of these, the shaking layer 11 containing clay is
It is formed as follows. First, as an excavation and shaping process, in order to form a recess as a waste disposal site, a backhoe or other excavator is used to excavate the ground into a predetermined shape, and a groundwater collecting and draining facility 8 is formed. The high-quality soil (top soil) was transported and spread evenly to a thickness of 30 cm with a bulldozer. (At this time, for the area around the groundwater collection and drainage facility 8, do not spread the high-quality soil and stock it aside. After that, it is to be spread after mixing and stirring with bentonite to be described later.) Spray the bentonite with a backhoe and spread it to a uniform thickness with human power.

Next, the high-quality soil and bentonite are mixed and stirred by a stabilizer. In addition, a place where mixing and stirring by the stabilizer is difficult is performed with a backhoe. Stirring is performed twice in principle, primary stirring and secondary stirring, and the degree of mixing is checked visually. Then, when the mixing and stirring by the stabilizer is completed, irregular shaping is performed with a bulldozer, and the roll is pressed with a roller.

The soil cement damping layer 6 is made by laying out the locally generated soil with a bulldozer to a predetermined thickness. After spreading, using a chemical sprayer such as a lime spreader, the solidified material such as cement was evenly sprayed, and after the solidified material was sprayed, the mixture was mixed twice using a mixer such as a stabilizer and uniformly mixed. Spread things to a predetermined thickness with a bulldozer.

After the spread is completed, rolling is performed by a bulldozer and a vibrating roller. After rolling is completed, the surface is finished with a vibro plate, hand guide roller, etc. In the slope section, after leveling is completed, shaping is performed by a bulldozer also serving as rolling pressure, and the slope of the slope is blown and shaped by a backhoe with a slope bucket. After the shaping is completed, rolling is performed by a vibrating roller with a slope winch.

After confirming that predetermined compaction has been achieved by RI measurement, a curing mat or the like is arranged on the surface, and water curing is performed for about 3 days.

The water-sealing layer 12 made of a sheet is obtained by disposing the nonwoven fabric 3 above and below the water-sealing sheet 1. 3 and the water-absorbing sheet 1 and the nonwoven fabric 3 are laid and formed, and a stabilization treated soil layer 7 is provided thereon. Also,
At the edge of the waste disposal site, as shown in FIG. 5, a sheet fixing concrete 10 is buried to fix the ends of the water shielding sheet 1 and the nonwoven fabric 3.

A protective layer is formed on the water-blocking layer 12 made of a sheet. The protective layer is a stabilized soil layer 7 made of soil cement. The stabilization treatment soil layer 7 formed by soil cement in this way takes substantially the same construction procedure as that of the soil cement damping layer 6, but in this case, it is necessary to have the same permeability as the soil cement damping layer 6. There is no.

In the above embodiment, an example of a final waste disposal site has been described. However, the present invention can be similarly applied to a water blocking structure such as an artificial pond such as a reservoir.

[0025]

As described above, the water-blocking layer structure of the waste disposal site of the present invention and the construction method thereof are made safe by using a multi-layer water-blocking structure using a variety of different water-blocking materials. In addition to forming a reliable water-blocking structure at the bottom and forming a water-blocking layer mixed with clay such as bentonite at the bottom, heavy equipment can safely ride on it, and harmful substances due to bentonite The removing action can also be used effectively.

[Brief description of the drawings]

FIG. 1 is a longitudinal side view of a final waste disposal site having a water blocking structure according to the present invention.

FIG. 2 is a vertical sectional side view of a bottom surface portion of a final waste disposal site having a water blocking structure according to the present invention.

FIG. 3 is a vertical side view of a slope of a final waste disposal site having a water blocking structure according to the present invention.

FIG. 4 is a vertical sectional side view of an arrangement portion of a leachate collection and drainage facility of a final waste disposal site having a barrier layer structure of the present invention.

FIG. 5 is a vertical sectional side view of a sheet fixing portion of the final waste disposal site having a water blocking structure according to the present invention.

FIG. 6 is a vertical sectional side view showing a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Shading sheet 2 ... Original ground 3 ... Nonwoven fabric 4 ... Drainage layer 5 ... Protective soil 6 ... Soil cement shading layer 7 ... Stabilized treatment soil layer 8 ... Groundwater collecting and draining facility 9 ... Leachate collecting and draining facility 10 ... Sheet fixing Concrete 11: Water blocking layer mixed with clay 12 ... Water blocking layer by sheet

Claims (3)

[Claims] 1. A waste disposal site characterized by a multi-layer water-blocking structure comprising a water-blocking layer containing clay such as bentonite in order from the bottom, a water-blocking layer made of soil cement, and a water-blocking layer made of sheets. And so on. 2. The water blocking layer structure of a waste disposal site or the like according to claim 1, wherein the protective layer provided on the sheet water blocking layer is formed as a soil layer stabilized by soil cement. 3. Excavating into a predetermined shape with an excavator, spraying bentonite to spread it to a uniform thickness, then mixing and mixing good-quality soil and bentonite, performing irregular shaping, and compacting. To form a water-blocking layer by bentonite, spread the locally generated soil on it to a specified thickness, spread it evenly, and then evenly spread a solidifying material such as cement using a chemical sprayer. After spraying, use a mixer to mix and spread the uniformly mixed product to a predetermined thickness, spread it and perform rolling after completing spreading, and after rolling is completed, finish the surface and remove soil cement. A non-woven fabric and a water-sealing sheet are laid on it to form a water-sealing layer with a sheet, and a stabilization soil layer is further provided on the water-sealing layer. Construction method of layer structure.