JP2011153401A - Injection pipe device and injection method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an injection pipe device and an injection method for injecting as large amount of grouting agent as possible under low pressure injection into as large scope as possible efficiently. <P>SOLUTION: In this injection method, an external injection pipe 8 with a grouting agent discharge port 8a is erected in a drilled hole 1, an internal injection pipe 9 is erected in the external injection pipe 8, a check valve 5 for opening and closing the grouting agent discharge port 8a and a columnar space water conveying member 6 covering a fixed scope L in the direction of pipe axis including the check valve 5, are attached to the external injection pipe 8, and the clearance 3 between the drilled hole 1 and the external injection pipe 8 is filled with seal grout 4. Cement or bentonite is used as the seal grout 4. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an injection pipe device and an injection method, and can inject a large volume of an injection material as uniformly as possible under a low pressure injection.

  Ground improvement by chemical injection is a method of injecting cement-based solidified material, water glass-based chemical solution or air bubble mixed solution into the ground using an injection tube inserted into the drilling hole, and mainly the water-stopping property of the ground. The purpose is to improve, increase the strength, prevent liquefaction, and fill the cavity.

  For example, as shown in FIG. 13, Patent Document 1 includes a plurality of injection material discharge ports 20a and check valves (not shown) that prevent back flow of the injection material at the injection material discharge ports 20a at the tip. When the injection material is injected into the ground through each injection tube 20, the independent injection tubes 20 are inserted into the drilling holes 21 such that the discharge ports 20 a are spaced from each other in the tube axis direction. The description regarding the injection pipe apparatus comprised so that injection material may be discharged in the surrounding ground by the check valve being expanded by injection pressure and the discharge port 20a opening is disclosed.

  Further, in Patent Document 2, as shown in FIGS. 14 (a) and 14 (b), an injection outer tube 22 installed in the bore 21 and an injection inner tube 23 inserted into the injection outer tube 22 are used. A description of an infusion tube device is disclosed.

  The injection outer tube 22 includes a plurality of injection material discharge ports 22a formed at predetermined intervals in the tube axis direction, and an outer tube packer comprising bag bodies attached on both upper and lower sides of each injection material discharge port 22a. 22b, 22b, and each outer tube packer 22b is formed so as to expand to a diameter larger than the inner diameter of the hole 21 by filling the bag body with a cement-based solidifying material or the like (FIG. 14 (a)). reference).

  Further, the outer tube packers 22b and 22b block the gap between the hole wall of the hole 21 and the injection outer tube 22 on both upper and lower sides of the injection material discharge port 22a, so that the hole wall of the hole 21 and the injection outer tube 22 are connected. A columnar permeation source 24 that is continuous for a certain length in the tube axis direction is formed therebetween.

  The injection inner tube 23 is provided with inner tube packers 23b and 23b on both sides of the injection material discharge port 23a and the injection material discharge port 23a at the tip, and the inner tube packer 23b is filled with air or fluid from the ground. The injection material is supplied into the injection material permeation source 24 through the injection inner tube 23 by closing the gap between the injection outer tube 22 and the injection inner tube 23 on both upper and lower sides of the injection material discharge ports 22a and 23a. It is comprised so that it can do (refer FIG.14 (b)).

  Then, in the injection stages A, B, and C, the injection material is supplied from the ground into the columnar infiltration source 24 through the injection inner tube 23, so that the periphery from the hole wall of the drilling hole 21 even if injection is performed at a high discharge speed. Can be infused into the ground at low pressure (infiltration between soil particles) (see FIG. 14B).

  Further, in Patent Document 3, as shown in FIG. 14 (c), in the injection tube device shown in FIGS. 14 (a) and 14 (b), a space formed between the upper and lower outer tube packers 22b and 22b. The description regarding the injection | pouring pipe | tube apparatus which installed the water-permeable hole wall protective member 25 in the columnar penetration | infiltration source 24 which consists of these, and was made to prevent a hole wall collapse is disclosed.

  Patent Document 4 discloses an injection system and an injection method for simultaneously injecting injection materials from a plurality of injection ports as shown in FIG.

Japanese Patent No. 2852721 Japanese Patent No. 3509744 Japanese Patent No. 3889408 Japanese Patent No. 3724644 Patent No. 2700614

  However, the injection pipe devices described in Patent Documents 1 and 4 are devices that inject an injection material at a preset point using a high-pressure pump, a pressure / flow rate management device, and a management system for monitoring and controlling these devices. (FIGS. 13 and 16 (a)), when injected at a high discharge speed, it becomes high-pressure injection and falls into pulse injection, and it is difficult to uniformly inject the injection material over the entire ground. Since low pressure injection is forced by discharge, a lot of injection time is required, and the injection efficiency per one injection tube is poor.

  The injection tube devices described in Patent Document 2 and Patent Document 3 (FIGS. 14 and 17) form a columnar penetration source including a space that is continuous for a certain length in the tube axis direction around the injection tube. This is a device that infuses and injects the injection material into the surrounding ground, but the conventional columnar infiltration source seals the columnar space between the injection tube and the hole wall in the tube axis direction for a certain interval by the outer tube packer. Therefore, the structure of the device is complicated, and there are problems such as an increase in work procedures.In the ground where the soil layers with different water permeability are finely volumed, the optimal injection is made by finely setting the injection stage. It was troublesome to form a columnar penetration source for reasons such as being difficult to perform.

  In addition, the injection material injected into another injection stage or another drilling hole may enter the columnar infiltration space and fill the space, making subsequent columnar injection impossible.

  By the way, since the ground usually has a different water permeability coefficient and porosity, the ground condition is different for each layer. When injecting a chemical solution into this kind of ground, as shown in FIGS. 16A and 16B, the injection pipe 26 is pulled up while being injected alone into the ground, or plural as shown in FIG. The injection material was sequentially inserted through the injection pipes 26 while the injection stage was moved up or down.

  Further, as shown in FIGS. 16C to 16E, after drilling by boring using the casing a, an injection pipe (double packer inner pipe) 26 installed in the seal grout 29 is inserted and rubber is inserted. The injection material was injected by moving up and down the injection stage while breaking through the seal grout 29 through the check valve 26a made of a sleeve.

  Since these are all based on the point injection shown in FIG. 16A, they have the drawbacks of the point injection as described above.

  However, the biggest problem in the injection method such as chemical solution injection is infiltration into a fine sand layer having a small water permeability coefficient or homogeneous infiltration into the ground composed of different soil layers.

  The water permeability to the fine sand layer is usually k = 10 −3 to 10 −4 cm / second, and in order to inject the chemical solution so as not to cause the destruction of the ground to such a soil layer, It is said that low pressure injection must be performed at a low discharge rate of 1 liter or less to several liters per minute.

  However, in the known infusion method described above, one set of infusion pump is used for each infusion tube. From the economical aspect of shortening the construction period as much as possible, and the performance limit of the pump. From 10 to 20 liters per minute, the injection pressure may increase and the ground may be destroyed. For this reason, the ground may be raised or the fine soil layer may not penetrate and be consolidated. Sometimes it was enough.

  In addition, when injecting into different soil layers, when the soil layer changes, it is practically difficult to change the injection rate in response to the soil layer change or to control the injection amount. In such cases, the injection material spreads in a large amount or only slightly penetrates in a certain layer. In such an injection state, there is a problem that continuity between adjacent solid bodies cannot be obtained. .

  In Patent Document 4, a plurality of injection pipes are arranged in the ground, and a plurality of unit pumps are provided in one plant when the ground improvement material is injected into the ground from the respective discharge ports through the plurality of injection pipes. The improvement material is pumped to each injection pipe by a multi-consecutive pump that simultaneously operates a large number of unit pumps, and is injected into the ground from the discharge port.

  In the above-mentioned known technique, it was necessary to use an injection material having a low clay and a gel time of 10 hours or more in order to obtain a wide range of consolidated diameters with a long injection hole interval (1.5 m to 4.0 m).

  However, once the injection material with a long gel time starts to deviate from the ground surface or the rough layer in the ground, the gelation time cannot be shortened, so the injection must be stopped, and during that time the grout is generated in the injection capillary. There was a problem of inconvenience such as gelation.

  Therefore, there has been a demand for an injection method that can infiltrate between soil particles even when injected from a single injection point with a large discharge amount, and can perform injection at an optimal injection pressure and injection rate for each injection point.

  16 (a) and 16 (b) show the principle of the point injection method. In the figure, the injection material injected into the ground by the injection pipe 26 is uniformly injected from the tip of the injection pipe 26 into the ground. Ideally, it is point injection from the injection material discharge port, so that spherical infiltration occurs. When the discharge amount is increased, high-pressure injection is caused and pulse-like injection is likely to occur.

  FIGS. 16C to 16E show a double pipe double packer method that has been conventionally used. After drilling in the casing a (FIG. 16 (c)), the injection outer pipe 26 whose discharge port 26a is covered with a check valve 26b made of a rubber sleeve is inserted into the casing a (FIG. 16 (d)), While filling the seal grout 29 (FIG. 16E), the casing a is pulled out.

  Then, after the seal grout 29 is solidified, an injection inner tube having a double packer is inserted into the injection outer tube 26 to inject the injection material into the ground (not shown). When the injection material is injected into the injection inner pipe, the check material 26 is opened by the injection pressure, whereby the injection material is injected into the ground. For this reason, the injection is performed by point injection, and there are problems similar to those shown in FIGS. 16 (a) and 16 (b).

  17 (a) and 17 (b) show the principle of the columnar injection method. In the figure, the injected material injected into the ground by the injection tube 26 is between the upper and lower outer tube packers 27, 27. Then, it is discharged into a columnar penetration source 28 formed in a predetermined length, and is injected from the columnar penetration source 28 into the surrounding ground. At this time, the injection material can be uniformly injected into the surrounding ground from the hole wall of the columnar penetration source 28.

  However, there is a possibility that an injection material from another injection stage or an injection material from an adjacent injection stage bypasses the outer tube packer 27 and is injected into the columnar penetration source.

  The present invention has been made in order to solve the above-described problems. An injection tube capable of uniformly injecting an injection material as large as possible under a low-pressure injection into the ground as wide as possible and capable of columnar injection. An object is to provide an apparatus and an injection method.

  In addition, since it can penetrate between soil particles even if the discharge amount is increased, even if the gap between injection holes is increased and the gel time is extremely long (10 to several tens of hours), a gel time of several hours is possible. In addition, there is no need to worry about backflow to the adjacent discharge port even when a long gelling is desired, and even if the target ground is complex, an injection tube device and an injection method that enable reliable injection for each soil layer or for each injection stage are provided. It is intended to do.

  Furthermore, while taking advantage of the multi-point injection pump by low-pressure osmotic injection of the injection material for the wide area ground developed so far, according to the injection situation of each injection pipe while maintaining the infiltration between soil particles by low-pressure injection, It is possible to arbitrarily manage the injection speed, injection pressure, injection stop, restart, gelation time, etc. by each unit pump, and to manage the operation of multiple unit pumps at the same time to grasp and manage the whole injection situation The purpose is to make the injection pipe device and the injection method possible.

  The injection pipe device according to claim 1, wherein the injection pipe device includes an injection pipe provided with an injection material discharge port and a check valve, and a portion having the injection material discharge port and the check valve. A columnar space water guide member attached to the injection pipe so as to cover a certain range of the above, and a seal grout filled in a gap between the hole wall of the drilling hole and the injection pipe. (Fig. 1).

  According to the present invention, a columnar permeation source made of a columnar space water-conducting member is provided outside the check valve that covers the discharge port in a certain length in the tube axis direction of the injection tube, and a seal grout is provided between the hole wall and the injection tube. In this way, a large volume of injection material can be injected into the surrounding ground from a columnar penetration source under low pressure.

  The injection pipe can be a steel pipe, a hard PVC pipe, or a biodegradable injection pipe, and the columnar space water guide member is a constant in the axial direction of the pipe including the portion having the injection material discharge port on the outer periphery of the injection pipe. It is possible to constitute a column penetration source in the range, and it is desirable that it has a certain thickness, is a net or sponge, and is formed from a material with high water permeability and elasticity into a cylindrical shape or a belt shape. Woven cloth, non-woven fabric, water-permeable synthetic resin material, various drain materials, and further, a net-like body or a basket-like body made of a tube, bag or resin fiber having a plurality of injection material discharge ports and injection material discharge slits, Furthermore, a synthetic resin tape or the like can be used. Moreover, these columnar space water guiding members need only be attached so as to cover a certain range in the tube axis direction of the injection pipe including the injection material discharge port and the check valve for preventing the backflow of the injection material at the injection material discharge port.

  The seal grout is a cement material that is easily cracked by the injection pressure of the injection material discharged from the injection material discharge port and solidifies to a low strength that can be crushed when injecting the injection material into the ground through the injection pipe, Bentonite, bentonite / cement material, lime, gypsum, or the like can be used.

  This seal grout prevents the drilling wall from collapsing, and each injection material discharge port of the injection pipe is closed by a check valve inside the columnar space water conveyance member, so that the discharge from the adjacent injection pipe discharges. There is no fear of the injected material flowing backward from the discharge port into the injection tube.

  Patent Document 5 of the conventional construction method describes a structure in which the spiral tape covers the discharge port of the injection pipe, but this spiral tape itself is used as a check valve, and is injected from the adjacent discharge port. Since the material flows back to the discharge port from the gap of the spiral tape, it does not function effectively as an injection tube.

  The length of the columnar space water conveyance member is usually about 0.1 to 3.0 m, preferably 0.2 to 1.0 m, longer than the diameter of the injection tube, and the length of the soil layer of the target stage. The thickness, soil layer structure, water permeability, discharge rate per minute, injection pressure, material and structure may be determined.

  The injection tube device includes an injection material discharge port and a check valve that prevents back flow of the injection material at the injection material discharge port, and the injection material discharge port is positioned at an interval in the tube axis direction. A plurality of injection pipes installed in the drilling hole, and a columnar space water conveyance member attached to the injection pipe so as to cover a certain range in the pipe axis direction including a portion having the injection material discharge port and a check valve; It is good also as a structure provided with the seal grout with which the clearance gap between the hole wall of the said drilling hole and the said injection tube was filled.

  In this case, the injection pipes may be inserted into the drilling holes individually or in a bundle. Further, the interval between the injection material discharge ports of each injection pipe and the installation length of the columnar space water guiding member can be arbitrarily set according to the properties of the ground.

  The columnar space water guide member may be individually attached in a cylindrical shape so as to cover a certain range of the portion having the injection material discharge port and the check valve, or a certain range of the portion having the injection material discharge port and the check valve. You may attach continuously so that it may cover in the direction of a pipe axis so that it may cover (refer to Drawing 2, 3, and 4).

  The injection tube device according to claim 2, wherein the injection outer tube installed in the drilling hole, the injection inner tube installed in the injection outer tube, the gap between the hole wall of the drilling hole and the injection outer tube And the injection outer pipe includes an injection material discharge port and a check valve, and a columnar space water guide covering a certain range in the tube axis direction including a portion having the injection material discharge port and the check valve And a member (see FIGS. 5 to 8).

  A plurality of injection material discharge ports, check valves, and columnar space water guide members may be provided at predetermined intervals in the tube axis direction of the injection outer pipe.

  According to this embodiment, by using the injection inner pipe shown in FIG. 9A as the injection inner pipe, the injection inner pipe is moved vertically in the injection outer pipe for each injection stage of the columnar space water guiding member. The injection material can be injected, and the injection material can be simultaneously injected into a plurality of injection stages at one injection point by using the injection inner tube shown in FIG. 9B.

  The injection tube device according to claim 3 is characterized in that, in the injection tube device according to claim 1 or 2, a packer is provided on both the upper and lower sides of the columnar space water guide member or on either one side.

  In the present invention, the gap between the hole wall and the injection tube is filled with a seal grout, and the upper and lower sides of each injection material discharge port are closed by a soil packer, thereby transferring the injection material to the other stage. Can be reliably prevented, and the injected material can be surely infused into the formation of a specific injection stage (see FIG. 5B).

  The outer tube packer may be installed at a narrow interval, and a grout with a short gelation time or a suspension type grout may be roughly packed and injected between them.

  The injection tube device according to claim 4 is an injection device using a plurality of injection tube devices according to any one of claims 1 to 3, wherein the injection material storage is connected to each injection tube device via a conduit. A tank, a plurality of unit pumps connected to each conduit and configured to operate with independent driving sources, respectively, for pumping the injection material from the storage tank to each injection pipe device, and to each conduit; A flow rate pressure detector for detecting the flow rate and pressure of the injected material, a valve connected to each conduit for starting and shutting off the pumping of the injected material, a rotational speed anomaly unit of the unit pump connected to each unit pump, and A central pump that controls a unit pump, a flow pressure detector, a valve, and a rotation anomaly machine, and each of the injection pipes of the injection pipe device is formed by a plurality of injection points at predetermined intervals. Signals of flow rate and / or pressure data at each injection point are transmitted from the flow rate pressure detector to the central control device, and the storage tank is monitored by the central control device in a batch while monitoring the injection status at each injection point. To each of the injection pipes at a plurality of injection points, each unit pump is operated to pump at an arbitrary injection speed, injection pressure, and injection volume, and at the same time or selectively injected into a plurality of injection points. It is characterized by.

  According to the present invention, it is possible to simultaneously or selectively inject an injection material into a plurality of formations at a plurality of injection points. Further, as shown in FIGS. 4 and 10 to 12, the injection can be performed simultaneously or arbitrarily from a plurality of injection tubes.

  In addition, an injection tube raising / lowering device for raising and lowering the injection inner tube of each injection tube device and an injection stage management device for managing the injection stage of the injection inner tube can be installed (FIGS. 10 to 12).

  An injection inner tube as shown in FIG. 9 (a) is used as an injection inner tube, and at each injection point, the injection inner tube is moved up and down by an injection tube lifting device, so that each injection can be performed simultaneously at a plurality of injection points. The injection material can be injected into each layer of the point in order.

  The injection method according to claim 5 is an injection method in which an injection material is injected into the ground using the injection tube device according to claim 1 or the injection device according to claim 4. A step of inserting a tube, a step of filling a seal grout in a gap between a hole wall of a drilling hole and an injection tube, and a step of injecting an injection material into the ground through the injection tube It is what.

  An injection method according to claim 6 is an injection method in which an injection material is injected into the ground using the injection tube device according to claim 2 or 3, or the injection device according to claim 4. Inserting the injection outer tube into the injection outer tube, inserting the injection inner tube into the injection outer tube, filling the gap between the drilling hole and the injection outer tube with a seal grout, and via the injection inner tube. And a step of injecting an injection material into the ground.

  The injection method according to claim 7 is characterized in that, in the injection method according to claim 5 or 6, an acidic to neutral silica solution is injected as an injection material.

  The present invention has the above-described configuration, and includes a check valve that opens and closes an injection material discharge port provided in the injection pipe in the injection pipe built in the drilling hole, and a constant in the axial direction of the pipe including the check valve. Column-shaped space water-conveying members that cover the area are respectively installed, and a seal grout is filled in a gap between the hole wall and the injection pipe, and in particular, a seal grout between the hole wall and the injection pipe Even if a large volume of injection material is injected into the surrounding ground from the hole wall of the drilling hole, a columnar seepage source consisting of a columnar space water conveyance member covered with is formed in a certain range in the tube axis direction. The material can be injected at a low pressure by columnar injection by breaking the seal grout from a range of a certain length covered with the columnar space water conveyance member. Also, the columnar penetration source can be easily formed in the seal grout by the columnar space water guiding member.

  In addition, the seal grout is destroyed for a certain length by the injection pressure of the injection material from each columnar space water conveyance member (columnar penetration source), and optimal injection is performed on a predetermined injection stage independently of each columnar space water conveyance member. .

  Further, in each injection stage, the check grout, the columnar space water guide member, and the check valve that covers the injection material discharge port of the injection pipe, the injection material from the other injection stage or the other injection pipe flows back into the injection pipe, Since the non-injected columnar space and the injection material discharge port are not blocked by the presence of the seal grout without blocking the discharge port, injection as planned or repeated injection is easy.

An embodiment of an injection tube device is shown, (a) is a front view of the injection tube, and (b), (c) are enlarged cross-sectional views of the main part thereof. It is a schematic diagram which shows the example of arrangement | positioning of the injection tube apparatus shown in FIG. (A)-(c) is sectional drawing which shows the procedure which installs an injection pipe in a drilling hole. An embodiment of an injection tube device is shown, (a) is a front view when a plurality of injection tubes are bound and installed, and (b) and (c) are enlarged sectional views of the main part thereof. An embodiment of an injection tube apparatus is shown, (a), (b) is a front view of an injection tube. The principal part of the injection tube apparatus shown in FIG. 5 is shown, (a), (b) are principal part expanded sectional views. 1 shows an embodiment of an injection tube device having a columnar space water conveyance member having a slit, (a) and (b) are front views of the injection tube, and (c) are cross-sectional views in (a) and (b). . 1 shows an embodiment of an injection tube device, wherein (a) is a cross-sectional view of a columnar space water-conveying member in which a water-permeable mat or net is formed into a cylindrical or basket shape and covers the injection tube, and (b) is a water-permeable mat used as an injection tube. Sectional drawing of the columnar space water-conveying member wound spirally around, (c) is a transverse sectional view in (a), (b). (A), (b) is a partially broken front view which shows an example of an injection | pouring inner tube | pipe. It is an outline figure of an injection tube device which shows one embodiment of an injection tube device, and was constituted so that injection material could be injected into the ground of a plurality of points simultaneously or selectively. 1 is a schematic diagram of an injection tube apparatus configured to be able to simultaneously or selectively inject an injection material into the ground of a plurality of injection stages at a plurality of points, showing an embodiment of an injection tube apparatus. It is an outline figure of an injection tube device which shows one embodiment of an injection tube device and was configured so that injection material could be injected into the ground of a plurality of injection stages simultaneously or selectively. It is sectional drawing which shows an example of the conventional injection tube apparatus. (A), (b), (c) is sectional drawing which shows an example of the conventional injection tube apparatus. It is sectional drawing which shows an example of the conventional injection tube apparatus. It is explanatory drawing which shows the principle of an injection method. It is explanatory drawing which shows the principle of an injection method.

  1 (a), (b) and (c) show an embodiment of the present invention. In the figure, an injection pipe 2 is built in a drilling hole 1. FIG. The injection tube 2 is formed of a steel tube, a hard PVC tube, a synthetic resin tube, or a biodegradable tube.

  In the gap 3 between the hole wall of the hole 1 and the injection tube 2, a seal grout 4 is filled over the entire length of the hole 1 or partially in the injection region of the injection material.

  The seal grout 4 is solidified in the drilling hole 1 to fix the injection tube 2 in the drilling hole 1, prevents the hole wall from collapsing in the drilling hole 1, and the injected material injected into the drilling hole 1 is a hole. It has a function of preventing escape in the gap 3 between the wall and the injection tube 2 in the direction of the tube axis of the injection tube 2, and is low enough to be easily crushed by the discharge pressure of the injection material even when solidified. Strong cement mortar, bentonite, low alkaline cement, lime, gypsum and the like are used.

  The tip of the injection tube 2 is closed, and one or a plurality of injection material discharge ports 2a are formed in the side portion of the tip so as to open laterally. The injection material discharge port 2a is expanded by an injection pressure of a rubber sleeve or the like, and is closed by a check valve 5 made of an elastic tube or bag that closes if not pressurized.

  The check valve 5 is mounted so that the discharge port 2a is opened by being expanded by the discharge pressure when the injection material injected from the ground via the injection pipe 2 is discharged into the ground from the discharge port 2a. .

  A columnar space water guiding member 6 is attached to the tip of the injection tube 2. The columnar space water guiding member 6 is attached so that the outer periphery of the tip of the injection tube 2 including the portion having the injection material discharge port 2 a of the injection tube 2 covers the certain section L in the tube axis direction of the injection tube 2.

  When the seal grout 4 is filled in the gap 3 between the hole wall in the drilling hole 1 and the injection pipe 2, the inside of the fixed section L in the vertical direction including the portion having the injection material discharge port 2a of the injection pipe 2 is included. Further, a columnar penetration source 7 covered with the seal grout 4 is configured.

  The columnar space water guide member 6 has a certain thickness and is formed in a cylindrical shape from a net-like body having water permeability. As shown in FIGS. 1A and 1B, the columnar space water guide member 6 has an outer periphery of the tip of the injection tube 2 including the portion having the injection material discharge port 2 a at the tip of the injection tube 2. It is attached so as to cover the fixed section L in the tube axis direction.

  In addition, the columnar space water conveyance member 6 may be a tubular covering the outer periphery of the injection tube 2 from a woven fabric, a non-woven fabric, a synthetic resin film material having a slit, a strip-shaped synthetic resin material, a cage, various drain materials, or the like, or FIG. ) Is formed in a continuous spiral shape along the outer periphery of the injection tube 2 as shown in FIG.

  In any case, the columnar space water guide member 6 is formed so as to have water permeability by having gaps or slits even if the material itself is water-permeable or the material itself is water-impermeable.

  The injection material injected into the injection pipe 2 is expanded into the columnar space water guiding member 6 as the columnar infiltration source 7 by pushing the check valve 5 from the injection material discharge port 2a and is discharged by the discharge pressure of the injection material. It is pushed out to the outside of the columnar space water guide member 6, and the seal grout 4 is broken and injected into the surrounding ground.

  Since the injection material discharge port 2a is covered by the check valve 5, the injection material discharged to the other injection stage from the fracture of the seal grout 4 once broken, or the other injection material discharge port is discharged. The injected material does not flow back into the injection tube 2. Moreover, it can inject | pour repeatedly from the same injection material discharge outlet 2a.

  Further, the mesh of the columnar space water conveyance member 6 is formed in a mesh shape so that the seal grout 4 does not enter, and since the seal grout 4 is highly viscous, the injection material is a mesh or slit of the columnar infiltration water conveyance member 6, or Since the flow does not flow back into the injection tube 2 from the spiral gap, the function of the columnar penetration source 7 can be maintained.

  In such a configuration, the injection material injected through the injection pipe 2 spreads the check valve 5 by the injection pressure of the injection material, and enters the columnar space water guiding member 6 from the injection material discharge port 2a or the columnar space. It is discharged between the water guide member 6 and the injection pipe to form the columnar permeation source 7.

  The injection material is pushed out from the column penetration source 7 to break the seal grout 4 by the discharge pressure, and is injected into the surrounding ground from the hole wall of the drilling hole 1 (infiltration between soil particles).

  At that time, the gap 3 between the hole wall of the drilling hole 1 and the injection pipe 2 is filled with the seal grout 4 over the entire length or a range of a predetermined injection depth, so that the injected material is displaced in the pipe axis direction. Never sent. Further, the injection material does not flow into the columnar permeation source 7 adjacent to the injection tube 2 in the tube axis direction or into another adjacent injection tube.

  FIG. 2 shows an installation example of the injection pipe device shown in FIGS. 1 (a), (b), and (c). As shown in FIG. 2, a plurality of injection pipes 2 have injection depths in the ground. It is installed at regular intervals.

  By performing the injection in such an arrangement, a large solid body corresponding to the length L can be efficiently formed on the ground, and the ground can be improved rapidly.

  In the present invention, by increasing the length L of the columnar penetration source 7, the injection hole interval D can be increased if injection can be performed at a low pressure even if the discharge amount is increased. It is suitable for liquefaction countermeasures because it can form a knot and can effectively and economically improve the ground.

  In particular, in the performance design of the recent liquefaction method, it is possible to obtain economics by leaving an unconsolidated portion as shown in FIG. 2 without completely consolidating a layer that is liable to be liquefied. For this purpose, it is desirable to inject a silica solution in a weakly alkaline, neutral or acidic region (pH 1 to 10) having a long gel time and excellent durability.

  Such a grout can be a silica sol grout obtained by neutralizing an alkali of water glass with an acid, a silica grout obtained by treating water glass with an ion exchange resin or an ion exchange membrane, or a mixture thereof.

  FIGS. 3A to 3C show a method of installing the injection pipe 2 in the ground. First, the hole 1 is formed using the casing a and the excavator b. Next, the injection pipe 2 having the discharge port 2 a at the tip and attached with the check valve 5 and the columnar space water guide member 6 is built in the casing a of the hole 1.

Then, the casing a is gradually pulled out while the seal grout 4 is filled in the casing a of the drilling hole 1. The injection tube 2 can be built into the hole 1 by the above procedure.
FIGS. 4A to 4C show another embodiment of the present invention, in which a plurality of injection pipes 2 are built in the hole 1.

  The tip of each injection tube 2 is configured in the same manner as the tip of the injection tube 1 described with reference to FIGS. That is, the tip of the injection tube 2 is closed, the injection material discharge port 2a is formed at the side of the tip, and the check valve 5 and the columnar space water guide member 6 are respectively attached. The columnar space water guiding member 6 is formed in a tubular or spiral shape (FIGS. 2B and 2C).

  Furthermore, the tip of each injection tube 2 configured in this way is arranged so as to be positioned at a predetermined interval in the depth direction of the drilling hole 1. A seal grout 4 is filled in the gap 3 between the hole wall of the hole 1 and each injection pipe 2 over the entire length of the hole 1.

  With such a configuration, in the gap 3 between the drilling hole 1 and the injection tube 2, a plurality of columnar permeation sources 7 that are continuous in a certain section L in the tube axis direction are formed at predetermined intervals in the tube axis direction. Then, by injecting the injection material into the plurality of injection tubes 2 at the same time, the injection material can be injected into the plurality of injection stages A, B, C, and D simultaneously.

  5 (a), 5 (b), FIG. 6, and FIG. 7 also show another embodiment of the present invention, in which an injection outer tube 8 is built in the drilling hole 1, and each injection outer tube 8 is built. An injection inner tube 9 is installed.

  Both the outer injection tube 8 and the inner injection tube 9 are formed of a steel pipe, a hard PVC pipe, a biodegradable injection pipe, or the like. Further, a seal grout 4 is filled in the gap 3 between the hole wall of the hole 1 and the injection outer tube 8 over the entire length of the hole 1 or the ground improvement region.

  The distal end of the outer injection tube 8 is closed, and a plurality of injection material discharge ports 8a are formed at a predetermined interval in the tube axis direction of the outer injection tube 8 on the side thereof. Further, a check valve 5 is attached to each discharge port 8a, and a tubular shape (Fig. 6 (a)) or a spiral shape (Fig. 6 (b)) or a tube shape (Fig. ), (B)) columnar space water conveyance member 6 is attached.

  As shown in FIGS. 6 (a) and 6 (b) and FIGS. 7 (a) and 7 (b), the columnar space penetrating member 6 is connected to the outer periphery of the outer injection tube 8 including the discharge ports 8a. A plurality are attached at predetermined intervals in the tube axis direction of the outer injection tube 8 so as to cover the fixed section L in the axial direction.

  Moreover, the columnar space water guide member 6 may be spirally attached to the outer periphery of the injection outer tube 8 so as to cover the discharge port 8 a and the check valve 5.

  With this configuration, in the embodiment of FIG. 6 (a), a plurality of columnar penetration sources 7 that are continuous in a certain section L in the tube axis direction within the gap 3 between the hole wall and the outer injection tube 8 are provided. It is formed at regular intervals in the tube axis direction.

  In the embodiment of FIG. 6B, a plurality of column permeation sources 7 that spirally continue in the tube axis direction in the gap 3 between the hole wall and the injection outer tube 8 in each section L are provided in the tube axis direction. Are formed at regular intervals.

  In particular, in the embodiment shown in FIG. 5 (b), an outer tube packer 8 b made of a bag body, a rubber tube or the like is attached between the columnar space water guiding members 6, 6 of the injection outer tube 8. These outer tube packers 8b are formed so as to expand to a diameter larger than the inner diameter of the hole 1 by filling a bag made of a bag, a rubber tube or the like with a cement-based solidifying material or a chemical solution from the ground. .

  Then, the outer wall packer expands and closes the gap between the hole wall of the hole 1 and the injection outer pipe 8 on both upper and lower sides of each columnar space water guide member 6, so that the hole wall of the hole 1 and the injection outer pipe 8 A plurality of gaps 3 can be partitioned in the tube axis direction.

  In addition, the outer tube packer 8b is formed in two stages, and then a quick-setting grout or a suspension type grout is injected between them, and then a rough soil layer or a soft injecting material is sequentially injected into a soil layer where it is easy to escape. Osmotic grout may be injected from the water guiding member.

  According to the present invention, the gap between the hole wall and the outer injection tube 8 is filled with the seal grout 4, and the upper and lower sides of each injection material discharge port 8a are closed by the outer tube packers 8b and 8b. The material can be reliably prevented from being transferred to other stages, and the injected material can be reliably infiltrated into the formation of the specific injection stage.

  FIGS. 7 (a), (b), and (c) show another embodiment of the present invention. In particular, the columnar space water guide member 6 is made of a water-permeable woven fabric, a synthetic resin film material having a slit, or the like. The injection tube apparatus formed in the bag shape or tube shape which continues in the direction is shown.

  Among them, the injection tube device illustrated in FIG. 7A is formed to have a fixed length that covers a certain length in the tube axis direction including the portion where the columnar space water guide member 6 has the injection material discharge port 2a of the injection tube 2. It is individually attached so as to cover the portion having each injection material discharge port 2 a, and its upper and lower ends are fixed in close contact with the injection tube 2.

  7 (b), the columnar space water guide member 6 is continuously formed in the tube axis direction of the injection tube 1 so as to cover the plurality of injection material discharge ports 2a. The upper and lower side portions 6a and 6a of the portion having the respective injection material discharge ports 2a that are continuously attached in the tube axis direction are firmly fixed to the injection tube 1 by an adhesive or the like. FIG. 7C is a cross-sectional view in FIGS. 7A and 7B.

  8 (a), (b), and (c) show another embodiment of the present invention, and in particular, the columnar space water guide member 6 is a tubular or continuous tube from the water permeable net material in the tube axis direction of the injection tube 2. An injection tube device formed in a spiral shape that is continuous in the tube axis direction of the injection tube 2 is shown.

  8 (a), the columnar space water guide member 6 is formed in a tubular shape covering a certain length in the tube axis direction including the portion having the injection material discharge port 2a of the injection tube 2, and each injection It is individually attached so as to cover the portion having the material discharge port 2a, and its upper and lower end portions 6a, 6a are fixed to the injection tube 2 in an intimate contact state with an adhesive or the like.

  In addition, the injection tube device shown in FIG. 8B is formed by continuously forming a columnar space water guiding member 6 in a spiral shape in the tube axis direction of the injection tube 1 so as to cover a plurality of injection material discharge ports 2a. The tube 1 is continuously attached in the tube axis direction. FIG. 8 (c) is a cross-sectional view in FIGS. 8 (a) and 8 (b).

  9 (a) and 9 (b) particularly show an injection inner tube, the tip of the injection inner tube 9 is closed, an injection material discharge port 9a is formed on the side of the tip, and the upper and lower sides sandwiching the discharge port 9a. A pair of packers 9b, 9b are attached to both sides. The packer 9b is configured to expand by injecting air or fluid in the gap between the outer injection tube 8 and the inner injection tube 9, and to seal the upper and lower sides of the discharge port 8a.

  In such a configuration, the injection inner tube 9 is set in the injection outer tube 8 and the packer 9b is expanded so that the discharge port 9a of the injection inner tube 9 and the discharge hole 8a of the injection outer tube 8 are located at the same level. As a result, an injection material flow path that communicates from the injection inner tube 9 to the columnar penetration source 7 is formed in the gap between the injection outer tube 8 and the injection inner tube 9.

  Then, when the injection material is injected into the ground through the injection inner tube 9, the injection material opens the check valve 5 by the injection pressure and is discharged into the columnar infiltration source 7 from the discharge port 8a. Then, the seal grout 4 can be broken from the columnar infiltration source 7 and can be injected into the surrounding ground from the hole wall of the digging hole 1.

  The injection inner tube may have a single tube or a plurality of tubes, may have a packer channel for forming an inner tube packer, or a fluid of the injection material that passes through the inner tube channel The packer may be activated by pressure.

  In addition, by moving the injection inner tube 9 in the tube axis direction within the injection outer tube 8, the injection material can be infiltrated and injected sequentially into the ground of each of the injection stages A, B, C, and D.

  In addition, the length of the columnar space water conveyance member 6 can be adjusted according to the ground condition. For example, for a layer with low water permeability, if the length of the columnar space water guiding member 6 is increased, a large amount of injecting material can be injected even under low pressure, and if a large consolidated diameter is desired, What is necessary is just to lengthen the length of the columnar space water conveyance member 6 and to enlarge the space | interval of the hole 1.

  The injection inner tube 9 shown in FIG. 9 (b) is provided with a plurality of sets of inner tube packers 9b, 9b on the upper and lower sides across the injection material discharge port 9a and the injection material discharge port 9a. By using this injection inner tube, the injection material can be injected simultaneously into the ground of a plurality of injection stages.

  FIGS. 10-12 shows the injection tube apparatus comprised so that injection material could be simultaneously injected into the multiple points of a target ground.

  In FIG. 10, drill holes 1 are formed at predetermined intervals at a plurality of points on the target ground, and the injection pipes 2 of the injection pipe device shown in FIGS. It is included.

  An injection material storage tank 10 in which an injection material is stored is connected to each injection tube 2 via a conduit 11, and each conduit 11 is used to pump the injection material from the injection material storage tank 10 to each injection tube 2. A unit pump 12, a flow rate pressure detector 13 for detecting the flow rate and pressure of the injected material at each injection point, and a valve 14 for starting and blocking the pumping of the injected material are connected to each other.

  Each unit pump 12 includes a rotation speed transmission 15 such as an inverter, and is configured to be individually operated by an independent drive source 16 such as a motor. Further, each unit pump 12, the rotational speed transmission 15, the flow rate pressure detector 13 and the valve 14 are respectively connected to a centralized management device 17, and all are individually controlled by the centralized management device 17.

  In such a configuration, when a flow rate / and / or pressure data signal from the flow rate pressure detector 13 is transmitted to the central control device 17, injection is performed from the storage tank 10 to each injection pipe 2 by the operation of each unit pump 12. The material is pumped at any injection rate, injection pressure and injection volume.

  At a plurality of injection points, the injection material is simultaneously or selectively discharged from the injection material discharge port 2a of each injection pipe 2 to the injection material penetration source 7, and further penetrates simultaneously from the injection material penetration source 7 into the surrounding ground. Injected.

  FIG. 11 shows an injection tube device configured to simultaneously inject injection materials into a plurality of injection stages A, B, C, and D at a plurality of injection points in the embodiment of FIG.

  In the figure, an injection tube 2 of the injection tube device shown in FIG. 4 is built in each drilling hole 1 formed at each of a plurality of injection points, and the tip of each injection tube 2 is the injection described in FIG. It is the same as the tip of the tube 2.

  That is, the tip of the injection tube 2 is closed, the injection material discharge port 2a is formed at the side of the tip, and the check valve 5 and the columnar space water guide member 6 are respectively attached. Furthermore, the tip of each injection tube 2 configured in this way is arranged so as to be positioned at a predetermined interval in the depth direction of the drilling hole 1. A seal grout 4 is filled in a gap 3 between the hole wall of the hole 1 and each injection tube 2 over a predetermined length. With such a configuration, in the gap 3 between the drilling hole 1 and the injection tube 2, a plurality of columnar permeation sources 7 that are continuous in a certain section L in the tube axis direction are formed at predetermined intervals in the tube axis direction.

  Further, other configurations such as an injection material storage tank 10, a conduit 11, a unit pump 12, a flow rate pressure detector 13, and the like are the same as those of the embodiment shown in FIG.

  Then, by simultaneously or selectively injecting the injection material into the injection tube 2 at each injection point, the injection material is simultaneously injected into the ground of the plurality of injection stages A, B, C, D at the plurality of injection points. Can do.

  FIG. 12 is an injection tube apparatus configured to inject injection materials sequentially or simultaneously into the ground of the injection stages A, B, C, D at a plurality of injection points in the embodiment of FIGS. Is shown.

  In the figure, an injection outer tube 8 of the injection tube device shown in FIGS. 5 and 6 is built in each drilling hole 1 formed at each of a plurality of injection points, and an injection inner tube 9 is inserted in each injection outer tube 8. Is built.

  Also, an injection inner tube lifting device 18 for changing the injection stage by raising and lowering the injection inner tube 9 and an injection stage management device 19 for managing the injection stage of the injection inner tube 9 are respectively attached.

  In other configurations, that is, the distal end of each injection outer tube 8 is closed, a plurality of injection material discharge ports 8a are formed on the sides thereof, and a check valve 5 is attached to each discharge port 8a. The point that the columnar space water guide members 6 are respectively attached is the same as that of the embodiment shown in FIGS.

  Further, the columnar space permeation member 6 has a predetermined outer circumference of the injection outer tube 8 including each discharge port 8 a so as to cover a certain section L in the tube axis direction of the injection outer tube 8 and in the tube axis direction of the injection outer tube 8. By being attached at intervals, a plurality of column-shaped permeation sources 7 continuous in a certain section L in the seal grout in the seal axial direction in the gap 3 between the hole wall of the drilling hole 1 and the injection outer pipe 8 are provided in the pipe axis direction. Further, they are formed in the same manner as the embodiment shown in FIGS.

  Further, the tip of the injection inner tube 9 is closed, an injection material discharge port 9a is formed at the side of the tip, and a pair of packers 9b and 9b are attached on both upper and lower sides of the discharge port 9a. In addition, the packer 9b is configured to expand by injecting air or fluid in the gap between the injection outer tube 8 and the injection inner tube 9, and to seal both the upper and lower sides of the discharge port 8a. This is also the same as the embodiment shown in FIGS.

  Moreover, the point which is equipped with the injection material storage tank 10, the conduit | pipe 11, the unit pump 12, the flow volume pressure detector 13, etc. is comprised similarly to embodiment shown in FIG.

  In such a configuration, when the flow rate and / or pressure data signal from the flow rate pressure detector 13 is transmitted to the central control device 17, the injection material in the storage tank 10 is arbitrarily set by the operation of each unit pump 12. It is pumped to each injection inner tube 9 at the injection speed, injection pressure and injection amount.

  Then, at a plurality of injection points, the injection material is discharged from the plurality of injection material discharge ports 8a of the respective injection outer tubes 8 into the plurality of columnar penetration sources 7, respectively, and further at the respective injection points from the columnar penetration source 7 to the surrounding ground. It is simultaneously injected into the inside.

  At that time, the injection inner tube 8 at each injection point is operated by the injection inner tube lifting / lowering device 18 in response to an instruction from the central control device 17, so that the injection inner tube 9 rises in the injection outer tube 8. The injection material can be sequentially injected into the ground of each of the injection stages A, B, C, and D at a plurality of injection points.

  In particular, by using the injection inner tube 9 shown in FIG. 9 (b), the injection material can be simultaneously injected into the ground of a plurality of injection stages A, B, C, D at a plurality of injection points. .

  In the embodiment shown in FIGS. 10 to 12, the unit pumps 12 usually constitute 5 to 100 units as a multi-injection device, and these unit pumps 12 are arranged horizontally, vertically or three-dimensionally in one set. Can be arranged as

  Each unit pump 12 can be operated by a drive source 16 such as a motor. Further, each drive source 16 can be operated by a rotational speed transmission 15 such as an inverter controlled by a centralized management device 17.

  Therefore, according to this embodiment, it is possible to configure as a single united infusion device which is composed of a large number of unit pumps 12 and has a small capacity as a whole and is compact.

  For this reason, when a plunger pump is used as the unit pump 12 in a set of multiple connecting devices, the discharge rate is 1 to 30 liters / min at 50 Hz, for example, when 10 units are used, the inverter is instructed by the central control device 17 Thus, while maintaining the optimal injection speed and injection pressure at a predetermined injection point, the entire injection amount from a large number of discharge ports (for example, 50 discharge ports) is controlled by the centralized management device 17 so that the total discharge amount is (1 to 1). 30) × 10 = 5 to 300 liters / minute is collectively managed, enabling low-pressure, low particle discharge and interparticle penetration, and shortening the construction period by rapid construction.

  In the present invention, a columnar infiltration source is individually formed on a plurality of injection stages at a plurality of injection points, and an injection material can be sequentially or simultaneously injected into the ground from each columnar infiltration source. An injection pipe device suitable for liquefaction prevention injection works that can infiltrate between soil particles at a low pressure even at an injection speed, can obtain a larger consolidated diameter, and requires economical ground improvement of large-capacity soil. provide.

DESCRIPTION OF SYMBOLS 1 Drilling hole 2 Injection pipe 3 Gap 4 Seal grout 5 Check valve 6 Columnar space water guide member 7 Columnar penetration source 8 Injection outer pipe 9 Injection inner pipe 10 Injection material storage tank 11 Conduit 12 Unit pump 13 Flow pressure detector 14 Check Valve 15 Rotational speed transmission 16 Drive source 17 Centralized control device 18 Injection inner tube lifting device 19 Injection stage management device 20 Outer tube packer

Claims (7)

  An injection pipe provided with an injection material discharge port and a check valve installed in the drilling hole, and the injection pipe so as to cover a certain range in the tube axis direction including a portion having the injection material discharge port and the check valve An injection pipe device comprising: a columnar space water-conveying member attached to the pipe; and a seal grout filled in a gap between the hole wall of the drilling hole and the injection pipe.   An injection outer tube installed in the drilling hole, an injection inner tube installed in the injection outer tube, and a seal grout filled in a gap between the hole wall of the drilling hole and the injection outer tube, The outer injection pipe includes an injection material discharge port and a check valve, and a columnar space water guide member that covers a certain range in the tube axis direction including a portion having the injection material discharge port and the check valve. Infusion tube device.   The injection tube device according to claim 1 or 2, wherein packers are provided on both the upper and lower sides or any one side of the columnar space water guide member.   An injection device using a plurality of injection tube devices according to any one of claims 1 to 3, wherein the injection material storage tank is connected to each injection tube device via a conduit, is connected to each conduit, and A plurality of unit pumps configured to be operated by independent driving sources and pumping the injection material from the storage tank to each injection pipe device, and a flow rate connected to each conduit to detect the flow rate and pressure of the injection material A pressure detector, a valve connected to each conduit for starting and shutting off the pumping of the injection material, a unit pump rotation speed anomaly connected to each unit pump, the unit pump, the flow pressure detector, the valve and A central control device for controlling the rotation irregularity machine, and the injection pipes of the injection pipe device are respectively inserted into drill holes formed at predetermined intervals at a plurality of injection points, and at each injection point The flow rate and / or pressure data signals are transmitted from the flow rate pressure detector to the central control device, and the injection status of each injection point is collectively monitored by the central control device, and the injection pipes at the plurality of injection points from the storage tank. An injection device characterized in that each unit pump is operated to pump at an arbitrary injection speed, injection pressure, and injection amount and inject simultaneously or selectively into a plurality of injection points.   A method of inserting an injection tube into a drilling hole in an injection method for injecting an injection material into the ground using the injection tube device according to claim 1 or the injection device according to claim 4; An injection method characterized by comprising a step of filling a seal grout in the gap between the hole wall and the injection tube and a step of injecting an injection material into the ground through the injection tube.   The injection tube device according to claim 2 or 3, or an injection method for injecting an injection material into the ground using the injection device according to claim 4, wherein the injection outer tube is inserted into the drilling hole. A step of respectively inserting an injection inner tube into the tube, a step of filling a seal grout in a gap between the drilling hole and the outer injection tube, and a step of injecting an injection material into the ground via the injection inner tube An injection method characterized by comprising:   The injection method according to claim 5 or 6, wherein a silica solution in an acidic to neutral region is injected as an injection material.

Images