JPH0573034U - Grout injection pipe structure - Google Patents

Abstract

(57) [Summary] [Purpose] Structurally simple and excellent in operability,
Moreover, it should be possible to prevent damage to the non-return skirt. [Composition] In an injection pipe having an opening through which a grout supplied from a base portion is passed through a wall of an outer pipe 31 and is discharged to a surrounding ground through a flow passage formed inside the outer pipe 31. , Outlets 35a, 35b, 36 connected to the inlets 2A to 2C
a, 38a are provided with flexible and restorative check skirts 41 to 44, the check skirts 41 to 44 having one end fixed to the injection pipe in a portion not covering the outlet.
The other end is not fixed and covers the entire outlet, and the outer surface is fixed so as to be recessed from the outer surface of the outer tube 31 toward the center of the injection tube.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a grout injection pipe structure having a check skirt having a check valve function.

[0002]

[Prior Art]

 Recent grout injection pipes have changed from conventional single pipes to double pipes or multi-passage pipes due to the complicated construction. In addition, a so-called compound injection method is used in which both the permeable grout having a long setting time and the instantaneous setting grout having a short setting time are injected.

On the other hand, in this type of grout injection, injection is performed using a drilling rod having a drilling bit at the tip. In this case, drilling water is often discharged from the tip, and grout is often injected from an injection port formed on the wall of the outer tube.

At that time, slime due to drilling may flow into the injection pipe from the injection port. Therefore, it is known to prevent the reverse flow of slime by providing a check valve biased by a spring, for example, in the vicinity of the inlet.

Further, as described above, in the step of injecting grout in the composite injection method or in the so-called instantaneous injection method, the material is hardened particularly near the injection port and the injection port is blocked. , Subsequent injection may be impossible.

On the other hand, there is a technique in which the inlet portion of the outer surface of the inlet tube is covered with a flexible sleeve to prevent backflow of slime and solidification of the material around the inlet.

[0007]

[Problems to be solved by the device]

 However, as described above, the structure in which the check valve is biased by the spring complicates the internal structure of the injection pipe, and its operation stability is poor.

Further, when the flexible sleeve is provided, the sleeve is exposed to the outer surface of the injection pipe, though the sleeve is functionally excellent, so that the injection pipe also serves as a drilling hole. During drilling, the sleeve will be damaged and will have to be replaced in a short time.

Therefore, an object of the present invention is to provide a structurally simple and excellent operability and to prevent damage to the check skirt.

[0010]

[Means for Solving the Problems]

 The above-mentioned problem is an injection pipe having an opening in which the grout supplied from the base penetrates the wall of the outer pipe and is discharged to the surrounding ground through the flow passage formed inside the outer pipe. A flexible and resilient check skirt is provided to cover the outlet connected to the inlet, and the check skirt has one end fixed to the inlet pipe and the other end not covering the outlet. This can be solved by making the part unfixed and covering the entire outlet, and further fixing the outer surface so that it is deeper on the injection tube center side than the outer surface of the outer tube.

In addition, the inner surface of the outer tube around the injection port forming portion has an inclined surface that inclines outward, and the inclined surface and the outer surface of the check skirt are separated from each other to guide the deformation of the check skirt. It is preferable that it is a surface. Furthermore, when using a two-part curable grout, check skirts are provided above and below the inlet with the non-fixed sides facing each other, and independent outlets of the flow passage are formed corresponding to each skirt. A suitable structure is such that these outlets communicate with the inlet.

[0012]

[Action]

 In the present invention, as shown in FIG. 6, skirt-shaped check valves 41 to 44 are provided inside each of the inlets 2A, 2B and 2C. Therefore, unless the grout liquids are supplied to the outlets 35a, 35b, 36a, 38a, the outlets are closed by the skirt check valves 41 to 44. Therefore, slime accompanying drilling and grout injected from a certain inlet do not flow backward from the outlet. Even if the grout material is solidified at the inlet, if the grout flows out from the corresponding flow channel with pressure, the pressure will cause the squirrel check valve to bend outward. , Put or exclude cracks in the grout material that is solidified at the inlet part. Therefore, the new grout material (liquid) is smoothly discharged as it is from the injection port.

On the other hand, as shown in FIG. 7, the skirt-shaped check valves 41 and 42 can be used as a guide wall for mixing the A liquid and the B liquid, which is preferable.

[0014]

【Example】

 The present invention will be described below with reference to the drawings and embodiments. First, before explaining the detailed structure of the injection pipe, a grout injection method capable of suitably using the injection pipe of the present invention will be described.

FIG. 1 to FIG. 5 are typical conceptual diagrams of the pouring method. First, as shown in FIG. 1, while pouring the inside of the ground by the pouring pipe 1 that also serves as a boring rod, The injection pipe 1 is inserted at a predetermined depth by inserting the injection pipe into a hole drilled by a hollow boring rod or a casing rod.

Next, as shown in FIG. 2, the flashing grout S is injected into the ground through an injection port 2A formed at the tip of the injection tube 1, for example, at the base of the injection tube 1 from the front end. As the instant setting grout, a solution type represented by a water glass system having a setting time of 60 seconds or less, or a cement type or cement bentonite type suspension type is used. By injecting this quick-setting grout, the gap between the drilling wall around the injection pipe 1 is filled, and pulsation is injected into the rough ground gap to prevent the subsequent outflow of grout to the ground side. The packer effect for this purpose and the improvement of strength due to rough packing for large gaps are aimed at.

After that, as shown in FIG. 3, from the injection port 2A, or from the injection port 2B from the tip side thereof, the suspension type having a longer solidification time and a higher homogel strength than the instant setting grout S. Inject reinforced grout R. As the suspension type grout, cement type or cement bentonite type is used. By injecting the reinforcing grout R, a large gap in the ground is roughly filled and the strength is increased.

At this time, since the flashing grout S has already filled the gap between the injection pipe 1 and the drilled wall above the injection port 2B, and the pulse injection has been performed to form the packer. The strengthening grout R does not escape to the ground side and is mainly injected below the improvement zone by the instantaneous setting grout S 1. Further, a part thereof enters the pulse injection portion of the instantaneous setting grout S and pushes it into the ground clearance, or even into the insufficient injection portion to strengthen the ground. Since the reinforcing grout R is a suspension type, there is also an advantage that the material cost can be reduced.

Moreover, since the strengthening grout R is of the suspension type, the effect of improving the strength is large as compared with the case of simply injecting the solution type instantaneous setting grout. A suspension type grout can be used as the instant setting grout. In this case, since it is a flashing grout, it mainly stays only in the vicinity of the injection tube 1 and is solidified, so that it does not penetrate to a certain distance. However, since the strengthening grout R has a setting time that is at least longer than that of the instant setting grout, the strengthening grout R penetrates farther, and there is also an advantage that the improved diameter becomes large.

Subsequently, as shown in FIG. 4, a solution-type permeable grout L having a longer solidification time than the instant grouting is injected from the injection position 2C of the reinforcing grout R or the injection port 2C on the tip side thereof. inject. As the solution type grout, a water glass type can be typically used. The permeable grout L is permeated and injected into a fine gap in the ground due to the fact that the material is a solution type and the setting time is long. Further, it also penetrates into the rough filling strengthening zone formed by the strengthening grout R previously formed, or passes through the strengthening zone or breaks and reaches a further distance to be solidified.

In this way, the unique functions of the quick-setting grout S, the reinforcing grout R, and the permeable grout L are interconnected, and as a whole, extremely ideal ground reinforcement can be achieved.

After that, the injection tube 1 is advanced or preferably stepped up by a predetermined length as shown in FIG. 5, and at that stage, the steps shown in FIGS. Strengthen the whole.

The injection ports of the flash-forming grout S, the reinforcing grout R, and the permeable grout L can be at the same injection position when injecting at least two kinds of grouts, but preferably on the base side. It is preferable that the injection ports for the binding grout S, the reinforcing grout R, and the permeable grout L are formed in order from the top to the tip side.

When injecting the instantaneous setting grout S, the strengthening grout R, and the permeable grout L, a main material and a reaction material are combined and mixed by a Y-shaped tube provided before entering the injection tube 1 or at the mouth of the injection tube 1. In addition to the above-mentioned aspect, preferably, in order to prevent the clogging of the flow channel due to the solidification in the flow channel of the injection tube 1, the mixture is merged and mixed in the injection tube 1, particularly in the tube at the tip thereof. .. In particular, when injecting the instant setting grout S, it is desirable that the flow paths of the main material and the reaction material are independent up to the confluent mixing portion.

As a solution to such a request, the injection tube 1 shown in FIGS. 6 to 8 in which only the tip portion is illustrated is preferably proposed.

In the injection pipe 1, three parallel first conduits 32, second conduits 33, and third conduits 34 extend from the base side in the outer pipe 31, and the first guide member 35 of the outer pipe 30 is provided. Is linked to.

The insides of the first conduit 32, the second conduit 33, and the third conduit 34, and the gaps between them and the outer pipe 31, respectively, are flow paths, and a total of four flow paths are formed. A second guide body 36 is provided below the inner body 35 of the first proposal at a distance, and a fourth conduit 37 is connected between the two guide bodies 36. A third guide body 38 is installed below the second guide body 36 with a space therebetween.

The first conduit 32 communicates with a first flow path 35A formed in the first guide body 35, and the first flow path 35A finally connects with a ring-shaped (annular) outlet 35a. There is. The second conduit 33 communicates with a second flow passage 35B formed in the first guide body 35, and the second flow passage 35B finally communicates with the ring-shaped outlet 35b. On the other hand, at the portions where the outlets 35a and 35b are formed, the outer pipe 31 is disconnected and connected by the first guide body 35, and the lower end of the upper outer pipe 31 and the upper end of the lower outer pipe 31 are connected to the first outer pipe 31. Between the outer circumference of the guide body 35 and skirt-like check valves 41, 42 made of a flexible material such as rubber that can be restored are provided with their bases fixed. It covers the outlet 35a and the outlet 35b.

Further, as shown in the figure, the inner surfaces of the lower end of the upper outer pipe 31 and the upper end of the lower outer pipe 31 are chamfered with an inclination, and as shown in FIG. The stop valves 41 and 42 are allowed to deform.

Thus, for example, when the main material A of the instantaneous setting grout S is supplied into the first conduit 32 and the reaction material B is supplied to the second conduit 33, they are respectively discharged from the outflow port 35a and the outflow port 35b. When flowing out, the check valves 41 and 42 are bent by the supply pressure as shown in FIG. At the same time, the main material A and the reaction material B are mixed and mixed in a small space surrounded by the check valves 41 and 42 to form a flash-forming grout S from the annular injection port 2A between the outer pipes 31 and 31. It is injected into the surrounding ground.

In the third conduit 34, for example, the above-mentioned reinforcing grout R is supplied. The reinforcing grout R escapes from the third flow passage 35C of the first guide body 35 into the fourth conduit 37, and flows out from the fifth flow passage 36A and the outlet 36a formed in the second guide body 36.

At this time, as in the case of the above-described structure example, the skirt-shaped check valve 43 is bent while being injected from the second injection port 2B.

The permeable grout L is supplied to the gap between the outer pipe 31 and the first conduit 32, the second conduit 33, the third conduit 34, and passes through the sixth flow path 35 D formed in the first guide body 35. However, it passes through the seventh flow path 36B of the second guide body 36, reaches the eighth flow path 38A of the third guide body 38, and flows out from the outflow port 38a. At this time, as in the case of the above-described structure example, the skirt-shaped check valve 44 is bent while being injected into the ground through the third injection port 2C.

When the injection pipe 1 is also used as a drilling rod, the outer pipe 31 that connects the second guide body 36 and the third guide body 38 is provided with a drilling bit 40 as shown in FIG. The outer tube 31 'at the lower end can be replaced. In this case, the drilling water W or the permeable grout L is poured out from the opening 31'a at the lower end of the outer tube 31 '.

In the present invention, as described above, the skirt check valves 41 to 44 are provided inside each of the inlets 2A, 2B and 2C. Therefore, unless the grout liquids are supplied to the outlets 35a, 35b, 36a, 38a, the outlets are closed by the skate check valves 41 to 44. Therefore, slime caused by drilling and grout injected from a certain inlet will not flow back from the outlet. Even if the grout material is solidified at the inlet, if the grout is caused to flow out from the corresponding flow passage with pressure, when the skirt check valve bends outward due to the pressure, The grout material solidified at the inlet part will crack or be eliminated. Therefore, the new grout material (liquid) is smoothly discharged as it is from the injection port.

On the other hand, as shown in FIG. 7, the skirt check valves 41 and 42 are suitable because they can be used as a guide wall for mixing the liquids A and B.

By the way, although the inlet is ring-shaped in the above example, the inlet may be formed by dividing the inlet in one or more parts in the circumferential direction, and therefore the skirt check valve also extends all around. It does not have to be in the form of a strip, and may be divided into a plurality of pieces covering the injection port in the circumferential direction. Further, the outflow port may not have a ring shape but may be formed with one or a plurality of openings in the guide body.

[0038]

[Effect of the device]

 As described above, according to the present invention, there is an advantage that the non-return means for slime or grout is structurally simple and excellent in operability, and the non-return skirt can be prevented from being damaged.

[Brief description of drawings]

FIG. 1 is a first process diagram for conceptually explaining an example of an injection method in which an injection pipe of the present invention is applied.

FIG. 2 is a second process drawing.

FIG. 3 is a third process diagram.

FIG. 4 is a fourth process drawing.

FIG. 5 is a fifth process drawing.

FIG. 6 is a vertical cross-sectional view of a structural example of a tip device for an injection tube according to the present invention.

FIG. 7 is a vertical cross-sectional view of an essential part of a state in which an instant setting grout is injected.

FIG. 8 is a view on arrow 8-8.

FIG. 9 is a vertical cross-sectional view of a main part of an alternative example of a distal outer tube.

[Explanation of symbols]

1 ... injection pipe, 2A, 2B, 2C ... injection port, 35a, 35b,
36a, 38a ... Outflow port, 41-44 ... Skirt check valve, S ...
Instant setting grout, R ... Reinforcing grout, L ... Penetrating grout.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Shohei Senda, 3-5-10 Matsuba, Ryugasaki-shi, Ibaraki Prefecture (72) Creator Naoki Yamamoto 2-2-11 Minamisuna, Koto-ku, Tokyo (72) Creator Yasuo Miyazaki Osaka 2-16-6 Minami Oimazato, Higashinari-ku, Osaka-shi, Japan (72) Inventor Yasunori Sato 8-11 Saitain-cho, Tennoji-ku, Osaka-shi, Osaka-shi

Claims (3)

[Scope of utility model registration request] 1. An injection pipe having an opening through which a grout supplied from a base portion is passed through a wall of the outer pipe and is discharged to the surrounding ground through a flow passage formed inside the outer pipe. A flexible and restoring check skirt is provided to cover the outlet connected to the inlet, and the check skirt has one end fixed to the inlet pipe at a portion not covering the outlet, A grout injection pipe structure, characterized in that the end portion is not fixed and covers the entire outlet, and further the outer surface is fixed so as to be recessed from the outer surface of the outer pipe to the center side of the injection pipe. 2. An inner surface of the outer tube around the injection port forming portion has an inclined surface inclined outward, and the inclined surface and the outer surface of the check skirt are spaced apart from each other, and the deformation guide surface of the check skirt is formed. The grout injection pipe structure according to claim 1. 3. Non-fixed skirts are provided above and below the inlet, and non-fixed skirts are provided, and independent outlets of the flow passage are formed corresponding to the respective skirts, and these outlets are the inlets. The grout injection pipe structure according to claim 2, which is in communication with the grout.