JPH0649835A - Filling pipe for grouting - Google Patents

Abstract

PURPOSE:To aim at the uniform solidification of the ground by filling the filling agent into the ground from fill-in ports of plural positions and the tip of the pipe side wall in the axial direction, and thereafter, repeating the work for raising a center runner by a predetermined distance. CONSTITUTION:Hole drilling water is supplied from an outer tube pipeline 2 to the tip passage 9, and a metal crown 13 is rotated for drilling and a filling pipe 1 is set at a predetermined depth. Next, the main agent is supplied from the pipeline 2, and the reaction agent is supplied from an inner tube pipeline 3, and a valve 8 is lowered to close the passage 9, and a plug 14a is removed to open a fill-in port 5a. The main agent under the pressurized condition removes a plug 14 of a fill-in port 5 to open the fill-in port 5. The filling liquid from the fill-in port 5 percolates mainly into a layer A, which has a large permeability in the horizontal direction, and the filling liquid from the fill-in port 5a percolates downward. Furthermore, the center runner 1 is pulled up to form a space C, and the filling liquid is filled to percolate into a layer B, which has a low permeability, between the layers A through the space C. The ground having a layer, which has a low permeability, can be thereby solidified strongly, and the construction is performed quickly and simply.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ground injection pipe having at least two pipe lines and having a plurality of injection ports at different axial positions, and more particularly, to a plurality of injection materials simultaneously in the ground. The present invention relates to a ground injection pipe for injecting and infiltrating it laterally and vertically so as to completely solidify the solidification effect and to solidify the ground extremely quickly and easily.

[0002]

2. Description of the Related Art Generally, a so-called composite pouring method is used as a technique for improving a complicated ground, in which a grout having a short setting time and a grout having a long setting time are poured into the ground.
Conventionally, a double pipe has been used to carry out this type of composite injection method.With this double pipe, a grout with a short setting time is first injected into the ground, and a rough portion, a weak portion, or an injection portion is injected. A method is known in which the space around the pipe is filled, and then grout having a long solidification time is injected between the soil particles and penetrated into the ground.

Further, a confluent liquid of two liquids separately fed from two pipe lines using a triple pipe (injection liquid having a short setting time)
A composite injection method is also known in which grouting is performed from the upper discharge port, and at the same time, grout having a long setting time is injected from the lower discharge port.

[0004]

However, in the former double pipe, since grouts having different setting times are separately injected, it is necessary to switch these grouts during injection, which complicates the operation. It has been impossible to inject quickly and easily. Furthermore, this injection pipe cannot increase the amount of liquid to be sent, resulting in low construction efficiency.

Further, the latter triple pipe allows simultaneous injection of grout having different setting times, but since it is a triple pipe, the diameter of the injection pipe becomes large, the drilling cost becomes high, and the construction efficiency becomes poor. Furthermore, this triple pipe is complicated because it requires adjustment of the composition of the main material, the reaction mixture composition for instant setting and the reaction composition formulation for slow setting.

[0006] Normally, the ground to which the pouring method is applied is soft ground, but in this ground, it is customary that layers having different water permeability are piled up in the horizontal direction in the process of ground formation. Therefore, the hydraulic conductivity in the horizontal direction is larger than in the vertical direction,
For this reason, the injected liquid easily penetrates along the horizontal water-permeable layer, but hardly penetrates into the small water-permeable layer between them.
Therefore, it is very difficult to uniformly consolidate the ground to be injected.

Therefore, an object of the present invention is to allow the injection liquid to permeate horizontally from the side wall injection port of the injection pipe, and at the same time to allow the injection liquid to permeate from the tip injection port into a layer that is difficult to permeate through the lower drilling space. Accordingly, it is an object of the present invention to provide an injection pipe for soil injection in which the soil is uniformly solidified to completely solidify the solidification effect, and the drawbacks existing in the above-mentioned known art are improved.

[0008]

In order to achieve the above object, according to the invention, there is at least two conduits,
And a ground injection pipe for injecting an injection material into the ground, the injection pipe having a plurality of injection ports at different axial positions, wherein at least one of the plurality of injection ports is provided on a side wall of the injection pipe. And, at least one is provided at the tip of the injection pipe, and an injection port communicating with one of the conduits is opened in the injection port, and at least one of these injection ports is connected with the other conduit. It is characterized in that the outlet is opened.

[0009]

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described below with reference to the accompanying drawings. FIG. 1 is a cross-sectional view of a specific example of an injection pipe according to the present invention, in which (a) is a state of sending drilling water (drilling water),
(b) shows the injection state. The injection pipe 1 is the outer pipe line 2
And the inner pipe line 3 and two side walls 4
At least one, and in the example of FIG. 1, three inlets 5 are provided laterally at different axial positions.

Further, these inlets 5, 5, ... 5 are provided with one or a plurality of injection ports 6, 6 ,. The injection ports 7, 7, ... 7 communicating with the pipe line 2 are opened respectively.

At least one injection port 5a is also provided at the tip of the injection pipe 1. For example, as shown in FIG. 1, the injection port 5a is provided downward and the injection port 5a
The injection port 7a communicating with the outer pipe line 2 and the injection port 6a communicating with the inner pipe line 3 are provided in a by inserting a valve 8 into the tip of the inner pipe line 3 respectively. Reference numeral 9 is a tip passage, and 10 is a valve. Normally, the tip passage 9 is closed from below by the bias of a spring 11. Reference numeral 12 is a holding base for the valve 10.

At the time of excavation, first, as shown in FIG. 1 (a), drilling water is fed in the direction of the arrow through the outer pipe line 2. The drilling water is sent to the tip passage 9, and the spring 11 of the valve 10 is pushed down to open the tip passage 9. The drilled water is discharged into the ground through the opened tip passage 9 to form a metal crown.
Helps 13 rotary drilling. In this way, the injection pipe 1 is set to a predetermined depth in the ground. At this time, each injection port 5,
Since 5 ... 5 or 5a are plugged with metal or synthetic resin stoppers 14 and 14a, respectively, perforation water will not leak from the stoppers.

Next, as shown in FIG. 1 (b), when the main material mixture liquid is fed from the outer pipe line 2 and the reactant mixture liquid is fed from the inner pipe line 3, respectively, the reaction is first carried out. The agent-mixed liquid slides down the valve 8 inserted in the tip of the inner pipe line 3 to close the tip passage 9 and, as shown in FIG.
The stopper 14a shown in (1) is skipped and removed, and the injection port 5a is opened. At the same time, the main material mixed liquid is pressurized in the outer pipe line 2 due to the blockage of the tip passage 9, blows off the plugs 14 of the inlets 5, and opens the respective inlets 5, 5 ,.

Of these plurality of inlets 5, 5, ... 5,
At least two, for example, at least one inlet 5 of the side wall 4 and the inlet 5a provided at the tip are respectively provided with one conduit, for example, the outer conduit 2
Is formed so that the ratio of the discharge amount from the other pipe line, for example, the discharge amount from the inner pipe line 3 is different. Specifically, as shown in FIGS. 5 (a), 5 (b), and 5 (c), the ratio of the number of injection ports 6 in one pipeline to the number of injection ports 7 in the other pipeline is different. Or as shown in FIGS. 6 (a) and 6 (b), the diameter of the injection port 6 of one pipe and the injection port 7 of the other pipe
Are formed such that the ratios of the diameters of the two are different from each other. Figure 1
Is an example in which the ratio of the caliber is different.

FIG. 2 is a cross-sectional view of another embodiment of the injection pipe according to the present invention, in which (a) shows a state of sending drilling water (drilling water) and (b) shows an injection state. In FIG. 2, the valve 8 is externally inserted at the tip of the inner pipe line 3, and the ratio of the number of injection ports of the outer pipe line 2 to the number of injection ports of the inner pipe line 3 at the injection port is equal to the side wall. 1 except that the injection port 5 of No. 4 and the injection port 5a at the tip of the injection pipe 1 are formed differently.
Is the same as.

3A and 3B are cross-sectional views of still another embodiment of the injection pipe according to the present invention, wherein FIG. 3A shows a state of sending drilling water (drilling water) and FIG. 3B shows an injection state. In the valve 8 of FIG. 3,
As in FIG. 1, the injection port 5a is provided downward, but the injection port that communicates with this injection port 5a is only the injection port 6a that communicates with the inner pipe line 3 and the outer pipe line 2 as shown in FIG. There is no injection port 7a communicating with.

In the injection pipe 1 of FIG. 3 described above, the gelling accelerator is fed from the outer pipe line 2 and the injection liquid having a long gelation time is fed from the inner pipe line 3. Therefore, the injection liquid having a long gelation time and the gelation accelerator are mixed at each injection port 5 of the side wall 4 to form an injection liquid having a short gelation time, and the injection liquid is injected into the ground. An injection liquid having a long gelation time is injected from the injection port 5a at the tip of the injection pipe 1.

FIG. 4 is a cross-sectional view of still another embodiment according to the present invention, in which (a) is a state of sending drilling water (drilling water),
(b) shows the injection state. In the injection pipe 1 of FIG. 4, the valve 8
3 is the same as that of FIG. 3, but is different from FIG. 3 in that there is only one injection port 5 of the side wall 4.

In the injection pipe 1 of FIG. 4 described above, as in the case of FIG. 3, the gelling accelerator is fed from the outer pipe line 2 and the injection liquid having a long gelation time is fed from the inner pipe line 3. It Therefore,
An injection liquid having a short gel time is injected from the injection port 5 of the side wall 4, and an injection liquid having a long gel time is injected from the injection port 5a at the tip. Also in this case, the ratio of the discharge amount from the injection ports 6 and 7 opened to the injection port 5 of the side wall 4 and the discharge amount from the injection port 6a opened to the injection port 5a at the tip of the injection pipe 1 is different. Is regarded as In this example, the injection port 7
May be a discharge port.

An example of an injection method using the injection pipe of the present invention having the above-mentioned structure will be described with reference to the schematic views of FIGS. First, as shown in FIG. 7, after setting the injection pipe 1 according to the present invention to a predetermined depth in the ground X, the injection liquid is injected simultaneously from the injection port 5 of the side wall 4 and the injection port 5a of the tip. The injection liquid from the injection port 5 of the side wall 4 mainly penetrates into a large horizontal water-permeable layer to form a permeation region indicated by A, and the injection liquid from the injection port 5a at the tip penetrates downward. B
To form a permeation region.

Then, as shown in FIG.
7 is pulled up by one stage to form a space C in the lower part of the injection pipe 1, and the injection liquid is injected at the same time as in FIG. 7, the injection liquid from the injection port 5 of the side wall 4 is in the permeation region A as in FIG. The liquid injected from the injection port 5a at the tip forms the permeation region B through the space C.

FIG. 9 shows a state in which the injection pipe 1 is further pulled up and the above injection is repeated. As a result, the ground is uniformly consolidated and the consolidation effect is perfect.

In the above-mentioned injection pipe of the present invention, the injection port 6,
Each of 7 or 6a and 7a is formed by narrowing the diameter. The squeezing of this caliber is due to
It is performed to such an extent that the injection material from a and 7, 7a produces a pressure with respect to the flow rate in the injection pipe, that is, to an extent that it is injected at a certain speed. This injection pressure is 1 kgf / cm ² or more, preferably 10 kgf / cm ² , and more preferably 15 kgf / cm 2.
^{Is 2} .

The main material used in the present invention is water glass or an injectable material which can be solidified by itself, and examples thereof include a mixed solution of water glass and a reactant, non-alkaline water glass grout, cement grout, and the like. , The reaction agent is various caking agents or caking accelerators, salt, alkali such as lime, non-alkaline water glass compounded solution, carbon dioxide gas, carbonated water, etc. for a mixed solution of water glass and a reaction agent, Examples of the non-alkaline water glass grout include water glass, cement, various salts of alkali, water glass grout and the like, and water glass, various salts of the cement grout, non-alkaline water glass compounding liquid and the like. Although not shown in the figure instead of the injection port 5 described above, a groove may be formed in the circumferential direction of the injection pipe. In this case, a rubber ring is fitted in the groove instead of the plug 14 of FIG.

In FIG. 12, a plurality of the injection pipes 1 of the present invention are installed on a predetermined ground X to be injected, and the liquids A and B are simultaneously added to these injection pipes 1.
This is an example in which the liquid is sent via the pumps P1 and P2 to inject and solidify the ground X. In this case, the construction efficiency is immeasurably improved.

[0026]

In the above-mentioned injection pipe of the present invention, at least one of the injection ports is provided on the side wall and at least one is provided on the tip end, so that the injection liquid from the side wall injection port has a large horizontal permeability. The layer is permeated and the infusate from the tip inlet is permeated downwards. That is, in the injection pipe of the present invention, the injection liquid can permeate in the horizontal direction and the vertical direction, so that the consolidation is performed uniformly and completely.

Further, in the injection pipe of the present invention, the injection port communicating with one of the conduits is opened in each injection port, and the discharge port communicating with the other conduit is opened in at least one of the injection ports. By sending the main material or the reactant simultaneously to one or the other of the conduits, the mixed injection liquid of the main material and the reactant and the injection liquid of only the main material can be injected simultaneously and at different positions in the axial direction. Can be injected from. For this reason, the injection pipe of the present invention not only completes the solidification effect, but also does not need to switch the injection liquid as in the conventional case, so that it can be solidified in the ground extremely quickly and easily. further,
In the present invention, if the ratio of the injection port diameter of the injection port is changed for each injection port and the main material is sent from the inner pipe line and the reactant is sent from the outer pipe line, the setting time of the solidification time from the upper discharge port is increased. The short grout fills the rough and fine parts of the upper layer, at the same time the grout with a longer gelation time is discharged from the middle discharge port, and the grout with a longer setting time is superposed and injected from the lowest discharge port. I will go.

Further, in the injection pipe of the present invention, at least two of the plurality of injection ports have a ratio of the discharge amount from one pipe line opened to these injection ports to the discharge amount from the other pipe line. Since they can be formed differently, at least two injection ports can inject injection liquids with different mixing ratios at the same time, for example, by simultaneously injecting an instantaneous injection liquid and a slow injection liquid. From this point as well, the injection pipe of the present invention can complete the solidification effect and form a homogeneous ground quickly and easily.

As described above, in the above-mentioned injection pipe of the present invention, the injection port having a small hole diameter is opened as the ejection port in the plurality of injection ports. In such an injection pipe, even if there is a difference in the permeation resistance of the ground around the injection pipe, or even if there is a difference in the permeation resistance of the ground near each injection port due to the progress of gelation during the injection, If at least the pressure in the pipe through which the main material mixture liquid passes is increased and injected from the injection port, the injection liquid is injected into the ground at a predetermined discharge speed from the injection port, and therefore multiple injection liquids are simultaneously injected into the ground. Injected.

Here, the injection function by injection in the present invention will be described with reference to FIG. 10 and FIG. When pumping water to a pipe with an inner diameter of 4 cm, almost no pump pressure is generated. An example of the result of measuring the injection pressure (pump pressure) and the discharge amount by mounting the tip portion having the injection port at the end of this pipe is shown in FIGS. 10 and 11.
Shown in. For comparison, the tip of the tube having 3 discharge ports each having a diameter of 1 cm was attached to the end of the tube and the number of the tip was set to 1 to 20.
Although water was fed at a rate of 1 / m, almost no discharge pressure was observed.

FIG. 10 shows a nozzle having a 1.0 mm nozzle diameter, and FIG. 11 has a 1.5 mm discharge port attached to a pipe. The pump pressure is changed variously and water is sent so that the pump pressure maintains a predetermined pressure. Moreover, the downstream side of the injection port is also connected by a pipeline, and a resistance pressure is applied by a valve in the pipeline to generate a pressure corresponding to the resistance pressure of the ground, and the flow rate discharged from the injection port in that case (1 / Min) and resistance pressure (kgf / cm ² ) were measured, and the results are shown in the graph. As is clear from FIGS. 10 and 11, for example, using a pump pressure of 80 kgf / cm ² , even if the resistance pressure (kgf / cm ² ) in the ground changes,
The flow rate from the nozzle is constant up to a resistance pressure of 50 kgf / cm ² .

That is, there is a region where a constant discharge amount can be obtained despite the change in the ground resistance pressure.
And it can be seen from FIG. Further, according to the experiment, for example, when injecting at a pump pressure of 30 kgf / cm ² , the injection amount on the ground (when the ground resistance pressure is zero) is approximately 3 l / min at a nozzle diameter of Φ 1.0 mm, and the nozzle diameter Φ 1 At 0.5 mm it is almost 6 l / min. This means that if the number of injection ports is adjusted to double the injection amount, the nozzle diameter Φ1.0 mm should be increased to two. To adjust the size of the nozzle diameter, the nozzle diameter Φ1 .0
Increase mm by 0.5 mm.

Therefore, even if the injection materials having different setting times are discharged from the respective injection ports, a constant discharge amount can be obtained even if the water permeability of the ground is different, and the ground is reliably solidified. You can In other words, the injection material with a short setting time is faster to set than the injection material with a long setting time, so the injection resistance of the surrounding ground is large, but nevertheless a constant flow rate corresponding to the nozzle diameter is secured. . In addition, the soil has different water permeability in each of the upper and lower layers, and therefore has different injection resistance, but nevertheless a constant flow rate is secured. Further, although the ground pressure (resistance pressure) changes in the ground due to various causes, a constant flow rate is always ensured nevertheless. Therefore, according to the injection pipe of the present invention, the pump pressure can be selected to a desired value. As a result, a constant discharge flow is secured, and the ground is reliably solidified.

[0034]

[Example] As an injection pipe, an inner diameter of 4 cm and an inner diameter of 2 c
m, inner wall thickness of 1 mm, two side wall inlets, and Fig. 5 (b)
Structure, the tip inlet is the structure of Fig. 5 (a), the inlet spacing is 50
The test construction was carried out on the injection ground in Tokyo using the type shown in FIG. The injection stage was raised every 1 m and injection was performed for a length of 4 m.

[Compounding] Liquid A: 35 liters of water glass per 100 liters, 7 liters of 75%, remaining water.
(PH about 1.7) Solution B: 3 liters of water glass per 100 liters, remaining water. When liquids A and B are combined at 0.5: 1.0 (volume ratio), gelation occurs in 8 seconds, when combined at 10: 1.0 (volume ratio) gels in 20 minutes, and when combined at 1.0: 0.5 gelation occurs in 60 minutes. To do. Liquid A was ejected from the inner pipe, and liquid B was ejected from the outer pipe. After excavation, it was confirmed that permeation and solidification of the injection liquid from each injection port was ensured, and a column-shaped homogeneously solidified body with a diameter of approximately 1.0 m and a length of approximately 4.5 m was formed. Was done. The injection procedure was quick and easy.

[0036]

As described above, according to the injection pipe of the present invention,
A plurality of injection materials are injected into the ground at the same time to allow them to penetrate in the horizontal and vertical directions, and even out the consolidation effect completely.
The ground can be consolidated very quickly and easily.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a specific example of an injection pipe according to the present invention, in which (a) shows a liquid supply state of drilling water and (b) shows an injection state.

2A and 2B are cross-sectional views of another specific example of the injection pipe according to the present invention, in which FIG.

3A and 3B are cross-sectional views of still another specific example of the injection pipe according to the present invention, in which FIG. 3A shows a state of sending drilling water and FIG. 3B shows an injection state.

4A and 4B are cross-sectional views of still another specific example of the injection pipe according to the present invention, in which FIG. 4A shows a state of sending drilling water, and FIG. 4B shows an injection state.

5 (a), (b) and (c) are all sectional views showing an example of an injection port in the injection port of the injection pipe of the present invention.

6 (a) and 6 (b) are cross-sectional views showing another example of the injection port in the injection port of the injection pipe of the present invention.

FIG. 7 is an explanatory view of a specific example of an injection method using the injection pipe of the present invention.

8 is an explanatory view showing a state where the injection pipe is pulled up one step by the injection method of FIG.

FIG. 9 is an explanatory view showing a state where the injection pipe of the present invention is repeatedly pulled up step by step.

FIG. 10 is a graph showing a relationship between a resistance pressure due to a change in pump pressure and a flow rate from a nozzle when the nozzle diameter is Φ 1.0 mm.

FIG. 11 is a graph showing the relationship between the resistance pressure and the flow rate from the nozzle due to a change in pump pressure for a nozzle diameter Φ 1.5 mm.

FIG. 12 is an explanatory diagram of an injection method using a plurality of injection tubes of the present invention.

[Explanation of symbols]

 1 injection pipe 2 outer pipe line 3 inner pipe line 4 side wall 5 injection port 5a injection port 6 injection port 6a injection port 7 injection port 7a injection port 8 valve

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[Procedure amendment]

[Submission date] March 8, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0023

[Correction method] Change

[Correction content]

In the above-mentioned injection pipe of the present invention, each of the injection ports 6, 7 or 6a, 7a is formed with a reduced diameter. The squeezing of the caliber is performed to the extent that the injection material from the injection ports 6, 6a and 7, 7a in the above-ground portion produces a pressure with respect to the flow rate in the injection pipe, that is, to such an extent that the injection material is injected at a certain speed. This injection pressure is 1 kgf /
cm ² or more, preferably 10 kgf / cm ² or more , more preferably 15 kgf / cm ² or more .

Claims (3)

[Claims] 1. An injection pipe for ground injection for injecting an injection material into the ground, the injection pipe having at least two pipe lines and having a plurality of injection ports at different positions in the axial direction. At least one of them is provided on the side wall of the injection pipe, and at least one of them is provided at the tip of the injection pipe, and an injection port communicating with one of the conduits is opened at the injection port. An injection pipe for ground injection, in which at least one of them has a discharge port that communicates with the other pipe line. 2. At least two of the plurality of inlets are formed so that the ratio of the discharge amount from one of the conduits opened to each of the inlets and the discharge amount from the other conduit is different. The injection tube according to claim 1, wherein 3. The injection pipe according to claim 1, wherein the discharge port communicating with the other pipe line of claim 1 is an injection port.