JP3194575B2 - Impermeable structures at waste disposal sites - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-impervious structure at a waste storage site in a waste disposal site, and more particularly to a water-impervious structure suitable for an extremely large and heavy industrial waste disposal site. .

[0002]

2. Description of the Related Art At present, both general and industrial wastes tend to increase, and their disposal is a major social problem. There is a concern about the influence on the surrounding environment over the treatment method and the installation location of the treatment facility, and improvement is demanded.

Generally, an industrial waste disposal site is provided with a place where a large amount of collected industrial waste is temporarily or long-term accumulated. For example, a large hole serving as a storage space was excavated in the ground, and after reinforcing the wall surface, waste was put into the hole and accumulated. Usually, industrial wastes having various shapes and weights to be put one after another will be randomly deposited in the holes. The size of such a hole has, for example, a depth and a diameter of 20 to 30 m.

[0004] As has become a problem these days, undesired substances can leach out of the surroundings from long-term deposited waste. In particular, there is a risk that extremely harmful substances may leak out of industrial wastes.Therefore, at the waste storage sites of the above-mentioned waste disposal sites, the walls that are the boundary with the surrounding ground shall be impermeable structures. Measures have been taken to prevent liquid substances from leaking into the surroundings. Therefore, a conventional general water-blocking structure has a layer structure composed of a plurality of layers such as a base layer for reinforcement, a water-blocking material layer for water-blocking, and a protective material layer for cushioning impact. . The underlayer has a function of securing the strength of the accommodation space. Since the load applied to the wall surface is considerably large due to the weight of the waste accumulated in the storage space, sufficient strength is required. The water-blocking material layer is made of, for example, a water-blocking sheet made of synthetic resin, and prevents the permeation of a substance from the accommodation space to the surrounding ground. The protective material layer is made of, for example, a rubber mat and serves to reduce the impact on the wall surface due to the input waste. The number and arrangement order of each layer are variously designed as necessary. For example, a base layer is provided as the outermost layer, and a protective material layer is provided as the innermost layer. As the underlayer,
Spraying concrete or mortar, litter, or
Ground improvement by the replacement method is generally used.

[0005]

However, in the conventional water-impervious structure, the underlayer for securing the strength is made of a rigid material, so that it has almost no viscoelasticity.
For this reason, there is no strength against impact and deformation. There has been a problem that local destruction or unevenness occurs in a high underlayer. If local destruction or unevenness occurs in the base layer that maintains the strength, local load concentration or elongation occurs in the water impermeable sheet layer, and the water impermeable sheet layer is often broken. As a result, the leachate from the waste will flow out to the surrounding ground. Once
If the underlayer or the impermeable sheet layer is destroyed, it is extremely difficult to repair and impermeable the leachate.

The present invention has been made in view of the above-mentioned problems, and in order to prevent leakage of leachate due to breakage or destruction of a seepage control structure at a waste disposal site, the present invention provides impact resistance, deformation resistance, and earthquake resistance. An object of the present invention is to provide a water impermeable structure having excellent properties.

[0007]

The object of the present invention is achieved by the following constitution. A first aspect of the impermeable structure in a waste treatment plant according to the present invention is a waste treatment plant having a storage space for installing and depositing waste on a ground, wherein the ground and the storage space are connected to each other. A water-blocking structure interposed therebetween, comprising a base layer made of a material including rubber fragments and a binding material in which the rubber fragments are dispersed.

[0008] A second aspect of the impermeable structure in the waste treatment plant according to the present invention is that the ground and the storage in a waste treatment plant which is installed on the ground and has a storage space for charging and depositing waste. A water-impervious structure provided interposed between the space, an underlayer made of a material including rubber fragments and a binding material in which the rubber fragments are dispersed, and a water-impervious material layer having water-impermeability, A protective material layer having an impact relaxation property.

[0009] A third aspect of the impermeable structure in a waste disposal plant according to the present invention is the above-described first and second aspects, wherein the rubber crushed pieces are cut into a fiber shape.
There is a feature.

[0010]

By using a material in which rubber fragments are dispersed in a binding material as a base layer of a water-blocking structure, the base layer has high viscoelastic properties. This absorbs and mitigates impacts, uneven loads, uneven settlement of the ground, or local distortions. Also, recoverability against deformation is increased,
Avoid breakage and destruction.

As described above, the underlayer has high viscoelastic properties, and the durability against impact and uneven load is improved. As a result, breakage or destruction of the underlayer can be avoided. The breakage and destruction of the can be prevented.

In the material of the underlayer, by making the rubber fragments dispersed into a fiber shape, the contact area with the binding material is increased as compared with the case of a granular shape, and the adhesion and the integrity with the binding material are improved. In addition, rubber elasticity is effectively exhibited as a whole material.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic cross-sectional configuration diagram showing an embodiment of a water shielding structure of a waste disposal site according to the present invention. The waste disposal site is configured by excavating a mortar-shaped hole that serves as a storage space with respect to the ground 60, and installing a water-blocking structure 10 interposed between the hole and the surrounding ground 60. The depth of the hole in the illustrated example is about 30 m. The waste 50 is put into this hole and deposited. Impermeable structure 10
Has a layer structure, and is arranged from the outside in the order of the underlayer 20, the water-blocking material layer 30, and the protective material layer 40.

The underlayer 20 secures strength for supporting the entire water-blocking structure 10. In the present invention, the base layer 20 is made of a material including rubber fragments and a binding material in which the rubber fragments are dispersed. The material of the underlayer 20 is a fluid at the time of construction and can be sent out by an appropriate liquid transfer device. Then, after the application, the underlayer 20 is formed by solidifying the binding material. Specifically, it is based on mechanical pumping by a pump car, blowing by compressed air, or pouring. The characteristics of the underlayer 20 will be described in detail with reference to FIG.

The water-impervious material layer 30 prevents the leachate from the waste 50 from flowing into the surrounding ground 60, and is made of, for example, a water-impervious sheet made of synthetic resin. Impermeable sheet layer 3
0 is provided so as to cover the entire underlayer 20. The protective material layer 40 absorbs and mitigates the impact at the time of dropping the waste 50 when dropped, and also prevents the waste 50 from directly colliding with the impermeable sheet layer 30 and being damaged. The protective material layer 40 is made of, for example, a rubber mat and is provided so as to cover the entire water-impervious sheet layer 30. Wastes 50 are stacked on the protective sheet layer 40.

FIG. 2 is a schematic partial enlarged view of the underlayer 20 of the water-blocking structure 10 shown in FIG. The underlayer 20
The rubber crushed piece 21 includes a binding material 22 in which the rubber crushed piece 21 is dispersed. By dispersing such an elastic material in the binding material, it is possible to impart high viscoelasticity to the underlayer 20. The rubber fragments 21 are preferably obtained by finely cutting waste rubber materials such as old tires. Specific materials include natural rubber (NR), styrene-butadiene rubber (SBR), and butadiene rubber (B
R), and in general, in the case of pulverized vulcanized rubber, NR,
SBR, BR, ethylene / propylene rubber (EPDM)
Is included. All of these rubber materials are suitable for the present invention. In addition, it is very economical because it can use waste materials such as automobiles. Moreover, since it is used in a relatively large facility such as a waste disposal site, such waste materials are consumed in large quantities, and the recycling of waste material resources Can be used. The binding material 22 is a solidifying material such as cement that disperses and hardens the rubber fragments 21.

As shown in the figure, the rubber crushed piece 21 is preferably cut into a substantially rod shape having a longitudinal direction, that is, a fiber shape. Of course, not all pieces of rubber need be cut into a fixed shape. The ratio of the average length in the longitudinal direction to the average length in the width direction of the fiber shape is 10 to 10
It only has to be in the range of 0. The fiber-shaped rubber crush pieces contain less air than rubber flakes having a substantially spherical or irregular shape, and have good adhesion to the binding material 22.
By increasing the adhesion area between each rubber fragment and the binding material such as cement, the elastic properties of the rubber itself can be exhibited more efficiently. Thus, the viscoelasticity and tensile strength of the material are improved. The underlayer 20 formed from such a material maintains the strength of the conventional solid underlayer,
It can also have effective viscoelastic properties. The mixing ratio of the rubber fragments 21 to the binding material 22 is appropriately adjusted according to the required degree of viscoelasticity.

When the underlayer is applied by spraying,
Due to the effect of the underlayer material being beaten to the construction surface by the injection energy, the fiber-shaped rubber fragments tend to be oriented substantially parallel to the surface of the underlayer as shown in FIG. This imparts lateral tensile elasticity to the underlayer, thereby improving the shape recovery of the underlayer that has been stretched and deformed in the lateral direction due to an impact on the surface of the underlayer. Further, since the material density is increased by spraying, there is an advantage that the strength of the construction surface is increased and the water permeability is reduced. On the other hand, in the case of pouring, the fiber-shaped rubber fragments are dispersed in a three-dimensionally random orientation, but in this case, exhibit the same good viscoelasticity even when subjected to an impact from any direction.

FIG. 3 is a graph showing the results of a compressive strength test of the material forming the underlayer of the water-blocking structure of the present invention. The vertical axis indicates the uniaxial compressive strength, and the horizontal axis indicates the amount of displacement of the material. Arrow A indicates the process of increasing the load, and arrow B indicates the process of decreasing the load. The underlayer material of the water-blocking structure of the present invention can follow a displacement of about 20%, and can restore its shape after the load is removed. Conventional materials are typically broken in the middle of the arrow A process. Thus, it can be seen that the underlayer of the water-blocking structure according to the present invention exhibits good durability and shape recovery properties against a compressive load.

In the embodiment shown in FIGS. 1 to 3, the water-blocking structure of the waste disposal site is composed of three layers, which are laminated in this order: a base layer, a water-blocking sheet layer, and a protective sheet layer. Although a simple example has been described, the layer configuration is not limited to this. For example, the order of each layer may be different, or each layer may be plural. Further, the shape of the impermeable structure forming the waste storage space is not limited to the illustrated example.

Further, the impermeable structure of the waste treatment plant according to the present invention can be applied to both general waste and industrial waste. In addition, not only for the small storage space of about several tens of meters shown in the example, but also for the large landfill where new land is formed by landfilling waste. Can be used as a stratum.

[0022]

As described above, the waterproof structure of a waste disposal site according to the present invention is a multilayer structure including a base layer made of a material in which rubber fragments are dispersed in a binding material, a waterproof material layer, and a protective material layer. Since it is formed by the structure, it can absorb the impact force at the time of waste input, and can prevent the occurrence of unevenness of the underlayer and the damage of the water barrier material layer and the protective material layer. Furthermore, it is possible to follow the uneven load caused by the variation in the weight of the input material or the deformation caused by the uneven settlement of the ground or local distortion, and it is possible to prevent the water-impervious structure from being damaged. Furthermore, the impact during an earthquake can be effectively absorbed by the underlayer having high viscoelastic properties. Further, when the underlayer is constructed by spraying, further strength and low water permeability can be ensured.

As a result, the impermeable structure of the waste disposal site according to the present invention realizes impact resistance, follow-up and restoration to deformation, seismic resistance, and low water permeability, and harmful substances leached from waste. Substances can be reliably prevented from leaking to the surrounding ground. Furthermore, resources can be effectively reused by using waste materials as materials of rubber fragments dispersed in the underlayer. Therefore, the present invention greatly contributes to safe disposal of waste and environmental protection.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional configuration view of an embodiment of a water shielding structure of a waste disposal site according to the present invention.

FIG. 2 is a partially enlarged view of a base layer of the water-blocking structure according to the present invention of FIG.

FIG. 3 is a graph showing the results of a uniaxial compressive strength test of a material used for an underlayer of a water-blocking structure according to the present invention.

[Description of sign]

 DESCRIPTION OF SYMBOLS 10 Water-blocking structure of a waste disposal site 20 Underlayer 21 Rubber crushed piece 22 Bind material 30 Water-blocking material layer 40 Protective material layer 50 Waste 60 Ground

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Akio Sasaki 5-11-3 Shimbashi, Minato-ku, Tokyo Toko Construction Co., Ltd. (56) References JP-A-7-60218 (JP, A) (58) Survey Field (Int.Cl. ⁷ , DB name) B09B 1/00 E02B 3/12

Claims (3)

(57) [Claims] 1. A water-impervious structure provided between a ground and the storage space in a waste treatment plant which is installed on the ground and has a storage space for charging and depositing waste. A water-impervious structure in a waste disposal plant, characterized by having an underlayer made of a material containing rubber fragments and a binding material in which the rubber fragments are dispersed. 2. A water-impervious structure provided between a ground and the storage space in a waste treatment plant that is installed on the ground and has a storage space for charging and depositing waste. A disposal comprising: an underlayer made of a material containing rubber fragments and a binding material in which the rubber fragments are dispersed; a water-blocking material layer having a water-blocking property; and a protective material layer having a shock-absorbing property. Impermeable structures in material processing plants. 3. The rubber crushed piece is cut into a fiber shape.
Water-impervious structure in waste treatment plant according to claim 1 or 2, characterized in that the those.