KR20080089177A - Solidification soil and method 0f solidification - Google Patents

Abstract

A solidification soil, and a method for solidifying the ground are provided to recycle charcoal ash and to allow a surface solidification layer to be formed on the weak ground effectively. A solidification soil comprises charcoal ash and weak soil in a ratio of 40:60 to 75:25 by weight and has a flake phase having a volume density of 8.5 kN/m^3 or less. Preferably the charcoal ash is mixed with the weak soil by hitting the charcoal ash and the weak soil with a rotating body with falling the charcoal ash and the weak soil. Preferably the solidified soil comprises further a solidifier.

Description

Solidified Soil and Solidification Method {SOLIDIFICATION SOIL AND METHOD 0F SOLIDIFICATION}

TECHNICAL FIELD This invention mainly relates to the solidified soil which can be used to form a surface solidified layer on soft ground, such as dredged soils, such as a sea area, a river, a lake, and a swamp.

DESCRIPTION OF RELATED ART Conventionally, the ground improvement method which inserts the strip | belt-shaped drain material into the ground from the surface of the soft ground, and discharges the soil gap water in the soft ground through the drainage material is developed as a soft ground improvement method. In the case of construction of super soft ground by dredged soil, this type of construction usually floats the plotter-type solidification treatment line, thereby improving the ground by inserting drainage material.In recent years, cement milk is applied to soft landfills such as dredged soil. The method of adding and mixing solidified materials, such as this, and forming a landfill ground layer using this solidified landfill soil, thereby forming a surface solidified layer on which land-driven ground-improved heavy machinery can run Is being studied.

Since the method for forming the surface solidified layer is intended to secure the traffic performance of the medium-term, it is relatively difficult for the solidification treatment such as uniaxial compressive strength qu28 = 50 kN / m 2 to 200 kN / m 2 for 28 days of age. It is often done at low intensity. This is because penetration of the mandrel becomes difficult when the strength is higher than this at the time of pouring the drainage material in the subsequent ground improvement work.

Moreover, as a method of mixing additive materials, such as a solidified material, with landfill soils, the method of carrying out air pressurization of the inside of a conveying pipe to the landfill input position in the form of slurry-like or slurry form, and the method of injecting an additive material in the meantime is developed.

In the conventional method of mixing the additives in a pipe, two pressure gauges are provided in which the slurry-like landfill soil is sandwiched between the air portions in the conveying pipe, and a plurality of masses are separated and moved by a plug. The volume and the moving speed of each plug to be moved are measured by using the A and the injection amount of the additive is controlled in correspondence with the passage of the additive injector position of each plug (see Patent Document 1).

In the conventional construction method, it is necessary to pressurize the landfilled soil through the conveying pipe, so that the place where the landfilled soil is injected becomes a specific place set at predetermined intervals, which is problematic in terms of work efficiency.

On the other hand, although it is conceivable to convey the landfill soil on the soft ground by flying the landfill soil with compressed air, the landfill soil and the like cannot fly the air efficiently.

In addition, various methods of effective use of coal ash generated from power generation facilities, etc. have been devised. However, in the past, most of them have been landfilled. However, due to problems with landfill paper, the method of treating landfilled coal ash has been studied. No effective use has emerged.

Patent Document 1: Japanese Patent Application Laid-Open No. 11-229428

SUMMARY OF THE INVENTION The present invention has been made in view of such a conventional problem, and an object of the present invention is to provide an effective solidified soil and a solidified treatment method for forming a surface solidified layer mainly on soft ground such as dredged soil.

The 1st aspect of this invention for solving the said subject is the solidified soil which mixes coal ash and soft soil, and is a solidified soil which is flake shape whose bulk density is 8.5 kN / m <3> or less.

In such a first aspect, by mixing the coal ash and the soft soil to form a flake shape having a bulk density of less than or equal to a predetermined value, the air conveyance property, in particular, the air conveyance property for flying and conveying the air by air pressure is significantly increased, It is possible to obtain a solidified soil having significantly improved workability of forming a surface solidified layer on the ground. Moreover, since it is a solidified soil which mixed coal ash and soft soil into flake form, even coal ash, especially the landfilled coal ash can be utilized effectively.

The second aspect of the present invention is the solidified soil described in the first aspect, wherein the mixing of the coal ash and the soft soil is a crushing mixture by striking the rotary body driven by rotating while dropping the coal ash and the soft soil. It is a solidified processing soil characterized by the above-mentioned.

In such a second aspect, the mixture of coal ash and soft soil is subjected to the rotation mixing method in which the mixture is crushed and mixed by striking the rotary body driven by rotation while dropping both, so that the flake-like solidification treatment having a bulk density of less than or equal to a predetermined value and excellent in air transportability You can get the Sat.

A third aspect of the present invention is the solidified soil described in the first or second aspect, wherein the mixing ratio of the coal ash and the soft soil is in the range of 40:60 to 75:25 by weight. .

In such a 3rd aspect, when the mixing ratio of coal ash and soft soils is 40:60-75:25 by weight ratio, it can be set as the solidified soil which has especially small bulk density and high air-feedability.

The 4th aspect of this invention is the solidification process soil which further contains a solidification material in the solidification process soil in any one of 1st aspect-3rd aspect.

In such a 4th aspect, it can be set as the solidification process soil which can form a more solid surface solidification layer by further containing solidification materials, such as cement and a lime solidification material.

A fifth aspect of the present invention is a solidification treatment method characterized by mixing coal ash and soft soil to form a flake-like solidified soil having a bulk density of 8.5 kN / m 3 or less, and air-feeding it onto the soft ground.

In such a fifth aspect, since the coal ash and the soft soil are mixed to form a flake shape having a bulk density of less than or equal to a predetermined value, the air conveyance property, in particular, the air conveyance property for flying and conveying the air by air pressure is significantly increased, By carrying out air conveyance, especially in the air and conveying this, a surface solidification layer can be formed on a soft ground efficiently, and workability can be improved remarkably. Moreover, since coal solidification soil which mixed coal ash and soft soil was used as flake form is used, even coal ash, especially the landfilled coal ash can be utilized effectively.

According to a sixth aspect of the present invention, in the solidification treatment method according to the fifth aspect, the mixing of the coal ash and the soft soil is performed by crushing mixing by striking the rotary body driven by rotating while dropping the coal ash and the soft soil. It is the solidification processing method characterized by the above-mentioned.

In this sixth aspect, the mixing of the coal ash and the soft soil is performed by the rotary mixing method in which the mixture is crushed and mixed by striking the rotary body driven by rotation while dropping both of them. A treated soil can be obtained and efficient solidification can be performed.

According to a seventh aspect of the present invention, in the solidification treatment method according to the fifth or sixth aspect, the mixing ratio of the coal ash and the soft soil is in the range of 40:60 to 75:25 by weight ratio. .

In this seventh aspect, the mixing ratio of the coal ash and the soft soil is in the range of 40:60 to 75:25 by weight ratio, so that the solidified soil can be made into a solidified soil having a low bulk density and a high air-pressability, in particular, so that the solidification treatment operation can be carried out more efficiently. I can do it.

An eighth aspect of the present invention is the solidification treatment method according to any one of the fifth to seventh aspects, wherein the solidification treatment soil further contains a solidifying material.

In such an eighth aspect, a more solid surface solidified layer can be formed by further containing solidified materials such as cement and lime-based solidified materials.

According to the present invention, when the surface solidified layer is formed on soft ground such as dredged soil, it is possible to effectively use coal ash, particularly landfilled coal ash, by using flake solidified soil having a predetermined bulk density using soft soil and coal ash. In addition, it is possible to provide a solidified soil having excellent air pressure-transporting properties, and to form a surface solidified layer on the soft ground with high functionality and efficiently.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described, referring drawings.

1 schematically shows an example of an apparatus for practicing the present invention. As shown in the figure, a sand pump 11 for loam is provided on a towing vessel 10 for transporting soft soil such as dredged soil of high concentration, and a loam pipe 12 is connected to the sand pump 11. The loam pipe 12 is introduced into the rotary crushing mixing device 30. The rotary crushing mixing apparatus 30 will be described later with reference to FIGS. 2 and 3. The rotary crushing mixing device 30 is provided with a hopper 14 for inputting coal ash, etc. together with the soft soil, and the solidified treated soil crushed and mixed with the rotary crushing mixing device 30 has a temporary storage tank ( 15) to be temporarily stored. In addition, the lower end of the temporary storage tank 15 is connected to the start end of the conveying pipe 16 to pneumatically pump the solidified soil.

Here, in the rotary crushing mixing apparatus 30, as shown in FIG. 2 which schematically shows a longitudinal section, and FIG. 3 which shows the cross section of a principal part, the support stand 32 is provided inside the casing 31, and the support stand 32 is shown in FIG. A plurality of support rollers 34 rotatably provided in a circumferential direction are provided on the horizontal axis penetrating the standing wall 33 in the horizontal direction, and on the support roller 34 a cylindrical shape having both upper and lower sides opened. The processing vessel 35 is rotatably mounted about its central axis. That is, the flange-shaped rail 36 and the gearwheel 37 are fixed to the outer peripheral surface of the vertical processing container 35, and the vertical processing container 35 is rotated by the support roller 34 via the rail 36. Possibly supported. In addition, a plurality of electric motors 38 are provided above the support 32 provided inside the casing 31, and the pinion 39 meshing with the gears 37 of the vertical processing container 35 is provided on the rotating shaft thereof. Attached.

The upper part of the casing 31 is covered with the upper cover 40 so that the rotating shaft 42 rotatably supported by the bearing 41 provided in the substantially center portion of the upper cover 40 penetrates the vertical processing container 35. It is prepared. The outer circumferential surface of the rotary shaft 42 is provided with plural places in the circumferential direction, four in the embodiment, plural in the axial direction, and three places in the embodiment, and each ring 43 has a plurality of rings. The rotating member 44 which connected this to the chain form is attached. On the other hand, the upper end of the rotating shaft 42 is provided with a pulley 45, the pulley 45 is connected to the pulley 47 and the drive belt 48 provided on the rotating shaft of the electric motor 46.

In addition, a scraper 50 is provided on the upper cover 40. The scraper 50 has a deodorizing member 51 disposed close to the inner circumferential surface of the vertical processing container 35, and the deodorizing member 51 has a crank shaft 52 and an electric motor 53 connected to the upper portion thereof. It reciprocates in the up-down direction by the crank mechanism which consists of the crank board 54 provided in the.

On the other hand, between the upper end of the vertical processing container 35 and the upper cover 40, a cylindrical upper chute 55 is fixed to the lower surface of the upper cover 40, and the opening of the upper chute 55 is the upper cover. It is connected to the inlet which is not shown in figure 40 for inject | pouring the material to mix-process. On the other hand, a lower chute 56 for discharging the solidified soil, which has an inverted cone shape and is formed by being crushed and mixed, is provided below the vertical processing container 35.

In order to mix the soft soil and coal ash by the rotary crushing mixing device 30, the vertical processing container 35 is rotated via the pinion 39 and the gearwheel 37 by first driving the electric motor 38. In addition, by driving the electric motor 46, the rotating shaft 42 is rotated at high speed through the above-described drive transmission system, and the plurality of rotating members 44 laid down by their own weight are horizontally supported to rotate at high speed. . In this state, when the soft soil and coal ash and cement are further added at a predetermined rate from an inlet not shown in the figure, the injected material drops from the upper chute 55 into the vertical processing container 35 and rotates at high speed while falling. It is crushed and mixed while being hit by the rotating member 44 which is the driven rotating body, and the flake-like solidified soil is discharged from the lower chute 56. On the other hand, at this time, the deodorizing member 51 of the scraper 50 reciprocated in the vertical direction by the electric motor 53, although the material during the crushing mixing or the crushed mixed material is going to be accumulated and grown on the inner circumferential surface of the vertical processing container 35. The vertical processing container 35 which rotates and cooperates to prevent deposition growth.

Thus, the solidified soil formed by crushing mixing by the rotary crushing mixing apparatus 30 is a flake shape with a bulk density of 8.5 kN / m <3> or less, and air conveyance property is remarkably improved. That is, such solidified soil is formed by being crushed and mixed by being hit by a rotating body that is rotated while dropping the soft soil and coal ash.

Here, 'soft weak soil' means that the water content exceeds the liquid limit in the vicinity of the liquid limit, for example, the water content is 80% to 400%. In addition, "coal ash" is a clinker ash or a fly ash, preferably a clinker ash. On the other hand, what was already landfilled as coal material may be used, and even if such coal material is used, it can be set as the flake shape which has a predetermined bulk density.

In addition, although the preferable mixing ratio of coal ash and soft soil changes with each water content ratio etc., when it is 40:60-75:25 by weight ratio, it will become a flake shape with a bulk density of 8.5 kN / m <3> or less.

Since the flake-like solidified soil having a bulk density obtained in this manner is excellent in air conveyance, the inside of the conveying pipe 16 is compressed by air and blown out of the conveying pipe 16 outlet to fly in the air. It can deposit by air-pressure over, and can deposit on the surface of the soft landfill ground 21 in layer form with very good workability, and can form the surface solidified ground 22. As shown in FIG.

Here, when the strength of the surface solidified ground 22 is insufficient, cement may be further mixed with the soft soil and coal ash as a solidifying material to obtain a solidifying treatment material having a predetermined bulk density. In addition, you may mix other additives, such as a slug slag and a soil, within the range which does not impair the objective of this invention.

In the present invention, the crushed solidification treatment material having a predetermined bulk density is obtained by rotating crushing mixing the soft soil and coal ash in this way, so that the solidification treatment material excellent in air transportability can be obtained. By flying and depositing, a surface solidified layer can be formed with very good workability.

(Example 1 and Example 2)

Next, an example is obtained in which a clinker ash is added to a soft soil made of dredged soil having a high water content ratio at a predetermined ratio, and crushed using the rotary crushing mixing device 30 described above to obtain a flake-like solidified material.

As soft soil, clay (loam, water content of 130%) and clinker ash were mixed at a wet weight ratio of 1: 1 and 3: 1 to prepare a solidified material. In the following, clinker ash is denoted by C and rom as R.

(Comparative Example)

As a soft soil, viscous soil (Rom, water content 130%) and clinker ash were mixed in a wet weight ratio of 1: 3 to prepare a solidified material.

(Test example)

According to the bulk density of the manufactured solidification material and the weight ratio distribution for each conveyance distance by air, the air transportability of the produced solidification material was evaluated. Table 1 shows the weight ratio of the air pumped distance.

C: R Compounding cost 1: 3 1: 1 3: 1 Bulk density (kN / ㎥) 8.96 8.33 6.96 Distance (cm) Weight ratio by distance (%) 45 93 36 6 90 7 45 38 135 0 15 35 180 0 4 14 225 0 0 5 270 0 0 2

As shown in Fig. 4, the bulk density of the mixed material was remarkably tended to decrease as the mixing ratio of the clinker ash became large. Therefore, by mixing clinker ash, the solidified soil becomes light and flake-shaped, and the conveyability by air can be improved.

In addition, from the result of the weight-by-distance weight ratio according to the conveyance by air shown in FIG. 5, when the mixing ratio of clinker ash and soft soil becomes a mixing ratio of clinker ash about 1: 1 and a bulk density becomes 8.5 kN / m <3> or less, conveyance distance You can see that the center of gravity is larger. Therefore, it can be seen that the air-feedability of the solidified material is preferably blended at least 40% by weight, preferably at least 50%, of the clinker ash.

1 is a view schematically showing an example of an apparatus for practicing the present invention.

FIG. 2 is a view schematically showing the longitudinal section of FIG. 1.

3 is a diagram schematically showing a cross section of the main part of FIG.

4 is a view showing the bulk density of the mixed material.

5 is a view showing the results of the weight ratio by distance according to the conveyance by air.

[Description of the code]

10... Tounsun

11... Sand pump

12... Loam pipe

14... Hopper

15... Temporary storage

16... A return pipe

17... Air pump

21... Soft landfill ground

22... Surface solidification ground

28... Jaeryong

30... Rotary Shredding Mixers

Claims (8)

A solidified soil comprising a mixture of coal ash and soft soil, wherein the solidified soil is flaky with a bulk density of 8.5 kN / m 3 or less. The method of claim 1, Mixing of the coal ash and the soft soil is crushed mixed soil by striking the rotary material being driven to rotate while dropping the coal ash and the soft soil. The method of claim 1, Mixing ratio of the coal ash and the soft soil is solidified soil, characterized in that the range of 40:60 ~ 75:25 by weight. The method according to any one of claims 1 to 3, A solidified treated soil further comprising a solid fire. A solidification treatment method comprising mixing coal ash and soft soil to form a flake-like solidified soil having a bulk density of 8.5 kN / m 3 or less, and air-feeding it onto the soft ground. The method of claim 5, Mixing of the coal ash and the soft soil is performed by crushing mixing by striking the rotary material being driven to rotate while dropping the coal ash and the soft soil. The method of claim 5, Mixing ratio of the coal ash and the soft soil is characterized in that the weight ratio ranges from 40:60 to 75:25. The method according to any one of claims 5 to 7, The solidification treatment method further comprises a solidified material.

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