JP2004156275A - Method and apparatus for treating lightweight soil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable long-distance conveyance using a carrier pipe, and to enable the addition and mixing of a solidifying material and a weight reducing material without the use of a conventional dedicated kneading machine using an agitating blade. <P>SOLUTION: In lightweight soil treatment wherein weight reduction and solidification treatment are performed by mixing the weight reducing material, such as foamed beads or air bubbles, and the solidifying material into adjusted mud (b) wherein a water content is adjusted by adding water to raw material soil (a), a lightweight soil treatment apparatus is constituted in such a manner as to feed the adjusted mud (b) into the carrier pipe 21, inject the solidifying material and the weight reducing material into the adjusted mud (b) through an additive-material injection nozzle 24 opened in the carrier pipe 21, press air for squeeze pumping into the carrier pipe 21 on a downstream side with respect to an injection place, convey the adjusted mud (b), into which the solidifying material and the weight reducing material are injected, to a desired placing site, and uniformly mix the solidifying material and the weight reducing material into the adjusted mud (b) by a mixing action which is caused during the movement of the adjusted mud (b) through the carrier pipe 21. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method and an apparatus for treating a lightweight soil in which a solidifying material and a lightening material are mixed into a raw soil to reduce the weight and at the same time to solidify.
[0002]
[Prior art]
The conventional lightweight soil treatment method is to add a solidifying material such as cement and a lightening material such as foam beads or bubbles to soil and knead them with a kneading machine, so that the density is smaller than that of a general soil material. It manufactures lightweight ground materials, and these lightweight ground materials are used for backfilling quays and seawalls, embankment on soft ground, backfilling underwater, and the like.
[0003]
As a conventional lightweight soil treatment method, for example, a method as shown in FIG. 6 is generally used. In this method, the raw soil a is put into a vibrating sieve 2 with a lifting device such as a backhoe 1 to remove impurities and put into a water content adjustment tank 3. Is added to adjust the water content, and the adjusted mud b after adjustment is fed into the kneader 6 by the pump 5. In the kneader 6, a solidifying material and a lightening material as additives are mixed. A cement material is mainly used as the solidifying material, and a predetermined amount of foam or foam beads is supplied from the solidifying material supply device 8 as the lightening material, and a predetermined amount is supplied from the lightening material supply device 8 as the lightening material. And the mixture is discharged from the discharge port 10. The discharged light-weight treated soil c is transported in the transport pipe 12 to a casting site by using a pumping device using a constant volume pump such as a squeeze pump 11. In the figure, 13 is a density meter for measuring the density of the adjusted mud b, and 14 is a flow meter for measuring the flow rate of the adjusted mud b.
[0004]
[Problems to be solved by the invention]
In the conventional lightweight soil treatment method as described above, since the kneading machine using the stirring blade is used for kneading the adjusted mud with the solidifying material and the lightweighting material, the working efficiency is low and the kneading machine is expensive. Therefore, there were problems in terms of capacity and economy in adapting to large-scale construction, such as high costs.
[0005]
In addition, since a constant volume pump is used to transport and place treated soil, it is difficult to transport the soil over long distances, and it is not possible to transport and place from a fixed position to a wide area. Was.
[0006]
In view of the above-mentioned conventional problems, the present invention enables long-distance transport using a transport pipe, and provides a solidified material and a lightweight material without using a special kneader using a conventional stirring blade. The purpose of the present invention is to provide a lightweight soil treatment method capable of adding and mixing a chemical material.
[0007]
[Means for Solving the Problems]
The feature of the method of the present invention for solving the conventional problems as described above and achieving the intended purpose is that the adjusted mud obtained by adding water to the raw material soil and adjusting the water content ratio has a light weight such as expanded beads or bubbles. In a lightweight soil treatment method for mixing and solidifying a material and performing a lightening and solidifying treatment, an additive injection nozzle in which the adjusted mud is fed into a transport pipe, and the adjusted mud is connected to the adjusted pipe in the transport pipe during the transport. The solidified material and the lightening material are injected through, and air for pressurizing is injected into the conveying pipe downstream from the injection point, and the adjusted mud into which the solidified material and the lightening material have been injected is fed to a desired casting site. The solidified material and the lightweight material are uniformly mixed with the adjusted mud by a kneading action that occurs during the transport and movement in the transport pipe.
[0008]
Further, the features of the lightweight soil treatment apparatus according to the present invention include a water content adjusting means for mixing the raw soil with water and adjusting the water content to a desired water content by adjusting the water content, a conveying pipe for conveying the adjusted mud, Adjusting mud sending-out means for feeding the adjusted mud adjusted for water content by the ratio adjusting means into the transport pipe, one or more additive material injection nozzles opened in the transport pipe, and a lightweight material and a solidified material added to the additive material injection nozzle Lightening material supply means and solidification material supply means for supplying water, control means for controlling the amount of lightening material and solidification material injected from the additive material injection nozzle, and a transport direction from the additive material injection nozzle in the transport pipe And a press-fitting air press-fitting means for press-fitting press-feeding air into the spaced portion.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, embodiments of the present invention will be described with reference to the drawings.
[0010]
1 and 2 show a first embodiment of the present invention using air bubbles as a lightening material. The same parts as those in the above-described conventional example are denoted by the same reference numerals, and description thereof will be omitted.
[0011]
In this example, the steps from the step of putting the raw material soil a into the water content ratio adjusting tank 3 constituting the water content ratio adjusting means and forming the adjusted mud soil b having the adjusted water content ratio are the same as the above-described conventional example. The adjusted mud b is sent into the transport pipe 21 by the pressurizing pump 20 which is an adjusted mud sending means. The transfer pipe 21 is for transferring the lightened treated soil c obtained by adding the solidifying material and the lightening material to the adjusted mud b to the casting site to the casting site.
[0012]
An additive injection nozzle 24 is connected to the start end of the transfer pipe 21. The nozzle 24 has a structure in which a plurality of discharge holes are formed in an injection pipe penetrating the transfer pipe 21 in the diameter direction. In addition, in addition to the above, the additive material injection nozzle may have a discharge hole opened in the inner wall surface of the transfer pipe 21.
[0013]
Bubbles are supplied to the injection pipe 25 communicating with the nozzle 24 by the lightening material supply means 30, and solidified material is supplied by the solidified material supply means 40.
[0014]
The lightening material supply means 30 has a foaming machine 31 that mixes air with a foaming agent to form air bubbles. The foaming machine 31 supplies a foaming agent contained in a foaming agent tank 32 to a pump with a flow rate control. By 33, it is sent through the flow meter 34. At the same time, the compressed air is sent from the compressor 35 to the foaming machine 31 through the flow control valve 36 and the flow meter 37 to form bubbles and to be sent to the injection pipe 25.
[0015]
The solidifying material supply means 40 is configured to weigh the solidifying material from a silo 41 containing a solidifying material such as cement into a mixer 42, add water, and knead the mixture to form a slurry. Thus, the liquid is fed into the injection pipe 25 through the flow meter 44.
[0016]
The injection amount of the air bubbles and the solidified material slurry from the nozzle 24 into the transport pipe is automatically controlled by control means using a computer (not shown).
[0017]
In this computer, according to the measured values of the density meter 13 for measuring the density of the adjusted mud b and the flow meter 14 for measuring the flow rate, the additive material including the air bubbles and the solidified material is sent out at a constant addition rate. Controlling.
[0018]
A portion of the conveying pipe 21 which is spaced from the insertion point of the additive injection nozzle 24 in the conveying direction from the insertion point, that is, downstream of the additive injection point in the conveying pipe 21, is provided by a pressurizing air injection means 22 comprising a compressor. The air for pumping is sent in. By this, the air for pumping is combined with the adjusted mud b into which the additive is injected, and the adjusted mud b is divided into plugs e sandwiched by the air layers d to be in a plug flow state, and can be transported in the transport pipe 21 for a long distance. Like that.
[0019]
Each plug e into which the additive is injected is moved while being stirred while moving in the transport pipe due to a difference in resistance between a portion in contact with the pipe wall and a central portion. The lightening treated soil c in which the additive is uniformly dispersed in the mud b is discharged as the soil, and is poured into a casting site.
[0020]
As the lightening material, foamed beads can be used in addition to the above-mentioned air bubbles. In this case, the lightening material supply means 50 shown in FIG. 3 is used instead of the lightening material supply means 30 in the first embodiment. . This is because the expanded beads stored in the storage tank 53 are thrown into the hopper 52 provided on the feeding side of the feeding screw conveyor 51 through the discharging screw conveyor 54, and the rotation of the feeding screw conveyor 51 is controlled to supply the beads. To adjust.
[0021]
In the above-described embodiment, an example in which a slurry type is used as the solidifying material supply means has been described. However, a powder type may be used. In that case, the solidifying material supply means in the above-described embodiment may be used. Instead of the means 40, a solidifying material supply means 60 shown in FIG. 4 is used. This is because the solidifying material is introduced into a powder feeder 61 from a silo 41 containing a solidifying material such as cement, and the powder feeding air is supplied from a dry compressor 62 while controlling the solidifying material addition amount with the powder feeder 61. To feed into the injection tube 25.
[0022]
Further, in the above-described embodiment, the lightening material and the solidified material are simultaneously injected using one additive material injection nozzle, but the lightening material and the solidified material are injected from separate nozzles. May be.
[0023]
Next, a description will be given of an experiment conducted on the effect of mixing the lightweight soil with the difference in the bubble addition position.
[0024]
Experimental method of mixing effect Pumping volume: 7.5 m ³ / h
Solidification material addition amount: 160 kg / m ³
Bubble addition amount: 140 to 160 l / min
In the treatment of the lightweight soil under the above conditions, the density of the lightened soil was measured in the case where air bubbles were added to the adjusted mud after air pumping and in the case where air blowing was performed after air bubbles were added to the adjusted mud.
[0025]
The experimental results are as shown in FIG.
Here, the theoretical density is a value calculated by calculating the theoretical density of the lightened soil when the additive is added and completely kneaded. The closer it is, that is, the closer the measured density is to the theoretical line, the higher the mixing effect.
[0026]
A comparison between the case where air pressure is added after air bubbles are added to the adjusted mud and the case where air bubbles are added to the adjusted mud after the air pumping is compared with the case where air pressure is added after the air bubbles are added to the adjusted mud as in the present invention. The density is closer to a theoretical line than the case where air bubbles are added to the adjusted mud after air pumping, and it can be seen that the mixing effect is higher when the air pumping is performed after air bubbles are added to the adjusted mud.
[0027]
【The invention's effect】
As described above, in the lightweight soil treatment method and the apparatus thereof according to the present invention, the adjusted soil obtained by adding water to the raw soil to adjust the water content ratio, the lightening material such as expanded beads or bubbles and the solidifying material. When performing the weight reduction and solidification treatment by mixing the above, the adjusted mud is fed into a transport pipe, and during the transport, the solidified material and the lightweight material are injected into the adjusted mud through an additive injection nozzle connected to the transport pipe. Then, pressurized air is injected into the transfer pipe downstream from the injection point, and the adjusted mud into which the solidified material and the weight-reducing material have been injected is transferred to a desired casting site, and during movement in the transfer pipe. By allowing the solidified material and the lightening material to be evenly mixed with the adjusted mud by the resulting kneading action, long-distance transportation of several hundred meters of lightened treated soil that could not be performed by the conventional method can be performed, Extensively It is possible to use a conventional kneading machine because the mud to which the weight-reducing material and the solidifying material have been added can be automatically kneaded in a uniform state during the movement simply by moving it in the transport pipe. This eliminates the need to do so, and the economic efficiency has been significantly improved.
[Brief description of the drawings]
FIG. 1 is an explanatory view schematically showing an apparatus according to the present invention.
FIG. 2 is an explanatory view showing details of a lightening material supply means in the apparatus shown in FIG. 1;
FIG. 3 is an explanatory view showing details of another example of the lightening material supply means in the apparatus shown in FIG. 1;
FIG. 4 is an explanatory view showing another example of a solidifying material supply unit in the apparatus shown in FIG.
FIG. 5 is a graph showing the results of a mixing effect experiment of the lightened soil.
FIG. 6 is an explanatory view schematically showing a conventional apparatus.
[Explanation of symbols]
a Raw soil b Adjusted mud c Lightweight treated soil d Air layer e Plug 1 Backhoe 2 Vibrating sieve 3 Water content adjustment tank 4 Pump 20 Pressurizing pump 21 Conveying pipe 22 Pressurizing air injection means 24 Additive material injection nozzle 25 Injection pipe Reference Signs List 30 Lightening material supply means 31 Foaming machine 32 Foaming agent tank 33 Pump with flow control 34 Flow meter 35 Compressor 36 Flow control valve 37 Flow meter 40 Solidification material supply means 41 Silo 42 Mixer 43 Pump with flow control device 44 Flow meter 50 Lightening material supply means 51 Screw conveyor 52 Hopper 53 Storage tank 54 Screw conveyor 60 for discharge Solidification material supply means 61 Powder supply machine 62 Dry compressor

Claims (2)

In a light soil treatment method of mixing a lightening material and a solidifying material such as foamed beads or air bubbles with an adjusted mud by adding water to the raw soil to adjust the water content, and performing a lightening and solidifying treatment,
The adjusted mud is fed into a transport pipe, and during the transport, a solidified material and a weight-reducing material are injected into the adjusted mud through an additive material injection nozzle connected to the transport pipe, and inside the transport pipe downstream of the injection point. And pressurized air is injected into the pipe, and the adjusted mud in which the solidified material and the lightening material are injected is transported to a desired casting site, and the solidified material and the lightened material are adjusted by the kneading action generated during the movement in the transport pipe. A lightweight soil treatment method that mixes evenly with mud. Water is mixed with the raw material soil, the water content ratio adjusting means for adjusting the water content to a desired water content ratio, a transport pipe for transporting the adjusted mud, and the adjusted mud water content adjusted by the water content ratio adjusting means into the transport pipe. Adjusting mud feeding means for feeding, one or a plurality of additive material injection nozzles opened in the transport pipe, lightening material supply means and solidifying material supply means for supplying the lightweight material and the solidifying material to the additive material injection nozzle Control means for controlling the amount of lightening material and solidified material injected from the additive material injection nozzle, and pressure feeding for press-fitting air for pressurization into a portion of the transport pipe separated from the additive material injection nozzle in the transport direction. Lightweight soil treatment device comprising air press-fitting means.

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