JP4165813B2 - Check valve for casing removal work and casing removal method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a check valve for casing removal work that can prevent the backflow of the grout material in the casing at the time of casing removal work, and a casing removal method using the check valve. About.
[0002]
[Prior art]
In the so-called casing removal work, in which the casing, which is installed in the anchor hole by the drilling work, is pulled out by one unit length as a straight composition tube body, and the exposed single body is removed by sequentially separating it from the casing. Since the volume in the anchor hole fluctuates (increases) by the amount that the casing is pulled out, additional injection of grout material that also serves as a supplement for this increase, so-called secondary injection, is parallel to the casing pulling process from the anchor hole. Done.
[0003]
However, when this anchor construction site is a groundwater discharge ground or the like, there is a possibility that the grout material pressurized and injected by this secondary injection operation will flow backward in the casing under the back pressure due to the groundwater pressure or the like. Such a backflow of the grout material hinders the operation of pulling out and separating the casing. Therefore, preventing the backflow of the grout material at the time of the secondary injection is one problem in the casing removal operation.
[0004]
Here, as an example of a configuration that can prevent the backflow of such a grout material, for example, a configuration using a casing packer as disclosed in Japanese Patent Application Laid-Open No. 7-259091 can be cited.
[0005]
This casing packer has a cylindrical elastic packer portion that is fixed at one end with respect to the tension member inserted and arranged in the anchor hole, and capable of expanding and contracting in the axial direction, and is slidably arranged with respect to the tension member. It is formed as a combination of a provided cylindrical sliding member serving as the movable portion and a cylindrical elastic packer portion that is urged together with the cylindrical sliding member in the contracting direction. And by the expansion against the urging force of the urging means by the pressure injection of a part of the grouting material into the inside of the cylindrical elastic packer part, the injection flow of the grouting material through the outer peripheral part of this casing packer is guaranteed. And by closing the inside of the casing with a convex annular portion of the cylindrical elastic packer portion that protrudes outward from the peripheral surface under contraction due to the biasing force of the biasing means after blocking the internal injection. The casing packer is configured to prevent the backflow of the grout material in the casing.
[0006]
[Problems to be solved by the invention]
Here, since the known casing packer disclosed in Japanese Patent Laid-Open No. 7-259091 is required to expand and contract in the axial direction of the tension material, the functionality of the casing packer is a cylindrical elastic packer. It depends on each operation performance of these movable members, such as the expansion / contraction performance of the part, the sliding performance of the cylindrical sliding member with respect to the tension material, and the expansion / contraction performance of the urging means.
[0007]
However, these movable members are all located in contact with the grout material, and adhesion of the grout material to these movable members is unavoidable. In order to fully draw out the performance, it is necessary to disassemble and clean and replace parts every time it is used.
[0008]
In other words, in the known casing packer, complicated maintenance is unavoidable and it is inferior in terms of ease of use.
[0009]
And since the convex annular part which obstruct | occludes the inside of a casing in this casing packer repeats that big expansion / contraction, the deterioration is comparatively easy to advance. In other words, this casing packer is not preferable in terms of maintenance cost because there is a possibility that many parts are required to be replaced.
[0010]
Further, since the sliding of the cylindrical sliding member with respect to the tension material is required, a clearance for ensuring the sliding is provided between the tension material and the cylindrical sliding member. However, if a foreign material such as grout material enters the clearance, the expansion / contraction of the casing packer itself may be hindered. Therefore, the possibility of a decrease in the function itself is also denied in this known casing packer. Can not.
[0011]
An object of the present invention is to provide a check valve for casing removal work that does not require complicated maintenance and can easily ensure its high functionality, and a casing removing method using the check valve.
[0012]
[Means for Solving the Problems]
In order to achieve this object, in the check valve for casing removal work according to the first aspect of the present invention, the check valve is formed from an impermeable elastic material in a substantially vessel shape with one end opened. The valve body capable of elastic deformation in the radial direction of the casing and the member body that can be fixed to the tension material head inserted and arranged in the casing are integrally fixed to the bottom of the valve body with respect to the member body. It is formed as a combination. And this check valve is arranged in the casing under the fixation to the tension material head with the arrangement of the valve body opening end in the casing drilling tip direction, the casing from the casing opening end. For the pressure injection of the grout material into the inside, under the reduced diameter elastic deformation by receiving the injection pressure of this grout material from the back side at the outer peripheral surface of the valve body, It is possible to guarantee the injection flow, and against the backflow of the grout material in the casing from the front end of the casing drilling hole, due to the expansion elastic deformation by receiving this backflow pressure inside the valve body. The check valve for casing removal work according to the present invention is configured so that the inside of the casing is blocked by the pressure contact of the valve body against the inner surface of the casing and the backflow is prevented.
[0013]
According to a second aspect of the present invention, the member main body is formed as a bottomed cylindrical body, and an opening end portion thereof is defined as a fixing portion for the tension material and has a predetermined fixing means, and is substantially The vessel-shaped valve body is embodied as a member that is at least partially covered from the bottom side with respect to the member body and fixed to the member body under the bottom overlap.
[0014]
Further, in claim 3 of the present invention, the bottom rear surface of the valve body is embodied as being fixedly covered by a support plate which is a rigid body.
[0015]
In claim 4 of the present invention, the support plate is embodied as an integral part of a flange that partially hangs on the outer peripheral surface of the valve body.
[0016]
Further, according to claim 5 of the present invention, the valve body is formed into a substantially lantern type in which an opening end and an intermediate portion thereof swell from the bottom portion, and the outer shape of the opening end of the valve body is the minimum diameter of the casing. It is embodied as one having a smaller diameter than the inner diameter of the part.
[0017]
Further, according to claim 6 of the present invention, the through pipe line penetrating the entire length in the direction along the axis of the tendon is embodied as being integrally fixed to the member main body.
[0018]
Further, in the casing removing method of the present invention as set forth in claim 7, a valve body which is molded from a non-permeable elastic material in a substantially vessel shape with one end opened, and capable of expanding and contracting in the casing radial direction, and the casing A member main body with respect to the tension material head with the arrangement of the valve body opening end in the direction of the casing drilling hole as a combination with a member main body which can be fixed to the tension material head inserted and arranged inside Are disposed in a casing as a linear composition tube. Then, in the state in which the valve body is in close contact with the inner surface of the casing in association with the pressure injection of the grout material from the opening end of the casing into the casing as the secondary injection at the time of removing the casing, the casing is at least from the anchor hole. The length of the single piece is pulled out, and the exposed single piece corresponding to the drawn out portion is sequentially removed from the casing and removed after the secondary injection of the grout material is interrupted.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0020]
The check valve for casing removal work according to the present invention can prevent the backflow of the grout material in the casing at the time of removing the casing from the anchor hole. As shown in FIG. The check valve 10 for removing the casing according to the present invention is configured to prevent the backflow of the grout material in the casing by the elastic expansion of the valve body 12 in the radial direction of the casing.
[0021]
As can be seen from FIGS. 2 and 3, the check valve 10 includes a substantially vessel-shaped valve body 12 made of an impermeable elastic material capable of expanding and contracting in the radial direction of the casing 13, and the inside of the casing. It is formed as a combination with a member main body 16 that can be fixed to the head portion 14a of the tension member 14 that is inserted and arranged in the head.
[0022]
The valve body 12 is formed in a substantially vessel shape having one end opened from an elastic material such as synthetic rubber, which mainly prevents fluid such as grout material and groundwater from passing therethrough. Specifically, for example, a substantially lantern type in which an intermediate portion of the opening end 12 a and the bottom portion 12 b swells can be exemplified as a substantially vessel shape of the valve body 12.
[0023]
And this valve body 12 is being fixed to the member main body under the bottom part overlap as a form which covers the member main body 16 at least partially from the bottom part 16a side, for example.
[0024]
The member body 16 is formed, for example, as a bottomed cylindrical body, and has, for example, an insertion hole 18 through which a tension material is inserted, and a bolt 20 that can project into the insertion hole under its screwing as fixing means. The opening end portion 16b is defined and formed as a fixing portion for the tendon material 14.
[0025]
As can be seen from FIG. 3, the bottom portion 12 b of the valve body is fixed to the bottom portion 16 a of the member body by, for example, three bolts 22.
[0026]
In this embodiment, the back surface of the bottom 12b of the valve body is covered with a support plate 24 that is a rigid body. The support plate 24 is integrally fixed together with the bottom portion 12b of the valve body to the bottom portion 16a of the member main body with the bolts 22 tightened together.
[0027]
As shown in FIGS. 2 and 3, such a check valve 10 is formed by inserting the tension member 14 into the insertion hole 18 and tightening the bolt 20 against the tension member, for example. That is, under the insertion arrangement of the tension material into the casing 13 which is fixed in advance to the rear end of the insertion and used as a drilling hole for the anchor hole, as shown in FIG. The valve body is disposed in the casing in a state in which the opening end 12a of the valve body faces the anchor hole bottom side, that is, the drilling hole front end side (left side in the figure).
[0028]
Reference numeral 26 in the drawing is a notch provided in the member main body 16 for preventing interference when the tension member 14 is inserted through the insertion hole 18 of the member main body.
[0029]
And after arrangement | positioning of the non-return valve 10 in the casing 13 as shown in this FIG. 3, the removal operation | work of this casing is performed in the following procedures roughly.
[0030]
In addition, working steps such as drilling of an anchor hole by the casing 13 as a linear composition tube, injection and filling of the grout material into the casing, and insertion and placement of the tension material 14 through the casing are the conventional processes. Since these are the same as those performed by the anchor method, and each of these work steps itself is not the gist of the present invention, detailed description thereof will be omitted here.
[0031]
In the casing removing operation, as shown in FIG. 4, first, the casing is subjected to secondary injection (pressurized injection) 28 of the grout material from the open end 13a of the casing 13 as a linear composition tube. It is pulled out for an appropriate length in the opening end direction, that is, in the pulling direction from the anchor hole (right side in the figure).
[0032]
At the time of this secondary injection 28 of the grout material, the valve body 12 receives the injection pressure of the grout material from the back thereof at the outer peripheral surface thereof, so that the diameter of the valve body is reduced by the injection pressure as shown in FIG. Under elastic deformation, the flow of grout injection between the valve body and the inner surface of the casing is guaranteed. Then, the release of the casing 13 without the valve body can be easily ensured by releasing the close contact of the valve body with the inner surface of the casing accompanying the elastic deformation of the valve body 12 with a reduced diameter.
[0033]
The drawing amount of the casing 13 at this time is at least one single length of the casing, and after this single length is drawn, the drawing and the secondary injection 28 of the grout material are temporarily interrupted.
[0034]
When such secondary injection of the grout material is temporarily interrupted, a backflow of the grout material in the casing occurs under the groundwater pressure due to the groundwater discharge or the like. However, as shown in FIG. 1, in the check valve 10 of the present invention, the valve body 12 disposed with the open end 12a facing the anchor hole bottom side receives the backflow pressure of the grout material 28 therein, Under this backflow pressure, the valve body is elastically deformed in the radial direction of the casing. Therefore, the backflow of the grout material is reliably prevented by the blockage in the casing accompanying the pressure contact of the valve body with the inner surface of the casing.
[0035]
If the exposed single body 13-1 exposed by pulling out the casing 13 is cut off in a state in which the grout material is prevented from flowing back by the check valve 10, the casing is cut off in a state that is not hindered by the backflow of the grout material. Removal is easily possible.
[0036]
As described above, the check valve 10 for casing removal work according to the present invention is intended to prevent secondary injection of grout material in the casing and its backflow prevention by expansion and contraction of the valve body 12 in the casing radial direction. Securing the slidability of the movable member in the axial direction with respect to the tension material 14 is not necessary.
[0037]
In other words, since the check valve 10 that does not depend on the sliding performance of the movable member can be easily ensured according to this, a decrease in operability due to contact with the grout material can be reliably ensured by this check valve. To be prevented.
[0038]
In the check valve 10 of the present invention, it is sufficient to dispose the substantially vessel-shaped valve body 12 opened at one end in the casing under the arrangement of the open end 12a on the anchor hole bottom side. Therefore, the simplification of the configuration can be sufficiently achieved.
[0039]
Therefore, according to the present invention, the highly functional check valve 10 can be easily secured without complicating the configuration.
[0040]
Further, in the check valve 10 having no movable member, it is sufficient to perform simple cleaning after the use so as to remove the attached grout material. Since both the valve body 12 and the member main body 16 have a simple shape, the cleaning itself is not complicated.
[0041]
Therefore, maintenance is not required, and the usability is surely improved.
[0042]
Furthermore, the valve body 12 in the check valve 10 is different from a known configuration that greatly expands and contracts at a specific location, and is not configured to intensively expand and contract at a specific location, so that the valve body 12 can be repeatedly expanded and contracted. However, deterioration due to the expansion and contraction is reliably suppressed. Therefore, frequent parts replacement or the like is not necessary, and also in this respect, the maintenance can be easily simplified.
[0043]
Here, as can be seen from FIG. 2 and FIG. 3, in the above-described embodiment of the present invention, the back surface (right side in the drawing) of the bottom 12b of the valve body is fixed by the support plate 24 made of a rigid body. However, since it is sufficient that the bottom portion of the valve body is fixed to the bottom portion 16a of the member main body, this support plate can be omitted.
[0044]
However, by covering the bottom rear surface of the valve body 12 with the support plate 24, excessive deformation of the valve body bottom 12a at the time of the diameter expansion elastic deformation due to the backflow pressure is surely prevented. The pressure contact accuracy to the inner surface of the casing is reliably improved. Therefore, according to the configuration in which the bottom rear surface of the valve body 12 is covered with the support plate 24, the certainty of closing in the casing due to the backflow pressure of the grout material is improved.
[0045]
If this support plate 24 is provided with a flange 24a that partially hangs on the outer peripheral surface of the valve body 12, it is possible to prevent the valve body from being excessively deformed. Certainty is further improved.
[0046]
Further, in this embodiment, the valve body 12 is embodied as, for example, a substantially lantern type in which an intermediate portion thereof swells from the opening end 12a and the bottom portion 12b, but has a substantially bowl shape having an opening at one end. Since it is sufficient, it is not necessarily limited to this.
[0047]
However, as shown in FIG. 3, if the outer diameter L1 of the opening end 12a of the valve body is a substantially lantern type that is smaller than the inner diameter of the smallest diameter portion of the casing 13, for example, the inner diameter L2 of the joint portion, Since the check valve 10 can be smoothly passed through the small-diameter portion, it is possible to reliably prevent the workability from being deteriorated when being disposed in the casing or when the casing is pulled out. And if it is the substantially lantern type which the opening part 12a and the intermediate part swelled from the bottom part 12b, even if an opening end is made into a small diameter, since the contact of the valve body surrounding surface with respect to a casing inner surface can be ensured, its diameter expansion elastic deformation The certainty of pressure contact at the time is not impaired.
[0048]
Further, the member main body 16 has a shape that can be fixed to the tendon head 14a, and a shape that allows the substantially valve-shaped valve body 12 to be fixedly supported is sufficient. The shape is not limited, and other shapes are also possible. However, if the member main body 16 is a bottomed cylindrical body and the valve body 12 can be fixed under the bottom overlap, the complication of the shape is surely prevented. This simplifies the configuration.
[0049]
And if it is the non-return valve 10 which consists of a combination of the valve body 12 of such a form, and the member main body 16, the direction along the axis line of the tension material 14 as shown in FIG.2, FIG.3 and FIG.5. Thus, it is possible to integrally fix the through-pipe line 30 penetrating between the entire lengths to the member main body.
[0050]
By providing this through pipe line 30, various fluid injection into the casing, for example, injection of a plurality of materials such as instantaneous grouting and admixture, becomes possible through this through pipe line. This check valve 10 can sufficiently cope with special grouting.
[0051]
In addition, in the case of closing the through pipe 30, as shown in FIG. 5, it can be dealt with by providing a plug 32 at the opening of the through pipe, and when this through pipe is not required at all. As shown in FIG. 6, the through-pipe is removed, and thereby, the member body bottom portion 16b, the valve body bottom portion 12a, and the continuous insertion hole 34 left in the support plate 24 are arranged on the back side of the support plate. By closing with the closed plate 36, the functionality of the check valve 10 is reliably prevented from being lowered.
[0052]
The above-described embodiments are for explaining the present invention, and do not limit the present invention. All modifications, alterations, and the like within the technical scope of the present invention are included in the present invention. It goes without saying that it is done.
[0053]
【The invention's effect】
As described above, according to the check valve for casing removal work of the present invention, the expansion and contraction of the valve body in the radial direction of the casing merely measures the secondary injection of the grout material in the casing, and the backflow prevention thereof, Since it is not necessary to secure the slidability of the movable member in the axial direction with respect to the tension material, it is possible to reliably prevent a decrease in operability due to contact with the grout material.
[0054]
In the check valve of the present invention, it is sufficient to dispose the substantially vessel-shaped valve body opened at one end in the casing under the arrangement of the open end on the bottom side of the anchor hole. The simplification of the configuration is sufficient.
[0055]
Therefore, according to the present invention, a highly functional check valve can be easily secured without complicating the configuration.
[0056]
Further, in this check valve having no movable member, it is sufficient to perform simple cleaning after use so as to remove the attached grout material. Since both the valve body and the member main body have a simple shape, the cleaning itself is not complicated.
[0057]
Therefore, maintenance is not required, and the usability is surely improved.
[0058]
Further, since the valve body in this check valve is unlikely to undergo intensive expansion and contraction at a specific location, the valve body can be repeatedly expanded and contracted, but deterioration due to the expansion and contraction is reliably suppressed. . Therefore, frequent parts replacement or the like is not necessary, and also in this respect, the maintenance can be easily simplified.
[0059]
According to the configuration of claim 2 of the present invention, the member main body is formed as a bottomed cylindrical body, and the substantially valve-shaped valve body is fixed to the member main body with its bottom overlapped. In this respect, since the complication of the shape is surely prevented, the overall configuration can be sufficiently simplified.
[0060]
Furthermore, according to the configuration of the third aspect of the present invention in which the bottom rear surface of the valve body is fixedly covered by a support plate that is a rigid body, excessive deformation of the bottom of the valve body during diameter expansion elastic deformation due to backflow pressure is prevented. Since it is reliably prevented, the accuracy of the pressure contact with the inner surface of the casing due to the elastic expansion of the diameter is reliably improved, and therefore the reliability of the blockage in the casing due to the backflow pressure of the grout material is improved.
[0061]
According to the configuration of claim 4 of the present invention, in which the support plate is provided with a flange that partially hangs on the outer peripheral surface of the valve body, the entire excessive deformation of the valve body can be prevented. The certainty of blockage in the casing due to the backflow pressure is further improved.
[0062]
In addition, according to the fifth aspect of the present invention, the outer diameter of the opening end of the valve body is formed to be smaller than the inner diameter of the minimum diameter portion of the casing, so that the check valve can smoothly pass through the small diameter portion of the casing. Therefore, it is possible to reliably prevent the workability from being deteriorated when being disposed in the casing or when the casing is pulled out.
[0063]
Furthermore, according to the configuration of claim 6 of the present invention, a plurality of penetrating pipes penetrating between the entire lengths in the direction along the axis of the tendon are integrally fixed to the member main body. Therefore, the check valve can sufficiently cope with special grouting that requires these materials.
[0064]
And, according to the casing removal method of the present invention shown in claim 7, since the secondary injection of the grout material in the casing and the backflow prevention thereof can be obtained without the sliding of the movable member with respect to the tension material, The casing can be pulled out and detached easily under the proper and smooth flow regulation of the grout material in the casing.
[Brief description of the drawings]
FIG. 1 is a schematic longitudinal sectional view of a check valve for casing removal work according to the present invention at the time of preventing backflow of a grout material.
FIG. 2 is a schematic perspective view of a check valve for casing removal work.
FIG. 3 is a schematic longitudinal sectional view of a check valve for casing removal work before secondary injection of grout material.
FIG. 4 is a schematic longitudinal sectional view of a check valve for casing removal work at the time of secondary injection of grout material.
FIG. 5 is a schematic longitudinal sectional view of a check valve for casing removal work, showing a closed state of a through-tube body.
FIG. 6 is a schematic vertical sectional view of a check valve for casing removal work when the through-pipe body is excluded.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Check valve 12 for casing removal work Valve body 13 Casing 14 Tension material 16 Member main body 24 Support plate 30 Through pipe body

Claims (7)

It is a check valve for casing removal work that makes it possible to guarantee the pressure injection of the grout material into the casing and to prevent the backflow of the grout material in the casing under the blockage in the casing,
A valve body that is formed from a non-permeable elastic material in a substantially container shape with one end open, and capable of elastically deforming elastically in the casing radial direction; fixable to a tension material head inserted and disposed in the casing And a member main body; are combined under the integral fixation of the bottom of the valve body to the member main body, and are fixed to the tension material head with the arrangement of the valve body opening end toward the tip of the casing drilling hole. In the casing,
For pressure injection of grout material into the casing from the opening end of the casing, the valve is subjected to the elastic deformation of the diameter by receiving the injection pressure of the grout material from behind the valve body outer peripheral surface. It is possible to guarantee the injection flow between the body and the inner surface of the casing,
For the backflow of the grout material in the casing from the front end side of the casing drilling hole, by receiving this backflow pressure inside the valve body, the pressure contact of the valve body against the inner surface of the casing under its expanded elastic deformation A check valve for casing removal work that closes the inside of the casing and prevents backflow. The member main body is formed as a bottomed cylindrical body, and the opening end portion thereof is defined as having a predetermined fixing means as a fixing portion for the tendon material,
The check for casing removal work according to claim 1, wherein the substantially valve-shaped valve body is fixed to the member main body under the overlap of the bottom portion so as to at least partially cover the member main body from the bottom side. valve. The check valve for casing removal work according to claim 2, wherein the bottom rear surface of the valve body is fixedly covered by a support plate made of a rigid body. The check valve for casing removal work according to claim 3, wherein the support plate is integrally formed with a flange partially hanging on the outer peripheral surface of the valve body. The valve body is formed into a substantially lantern mold in which an opening end and a middle portion of the valve body are swollen, and the outer diameter of the opening end of the valve body is smaller than the inner diameter of the minimum diameter portion of the casing. Item 5. A check valve for casing removal work according to any one of Items 1 to 4. The check valve for casing removal work according to any one of claims 1 to 5, wherein a through pipe passage penetrating the entire length in a direction along the axis of the tendon is integrally fixed to the member main body. A valve body that is formed from a non-permeable elastic material in a substantially container shape having an opening at one end; and a valve body that can be expanded and contracted in the radial direction of the casing; and a member body that can be fixed to a tension material head that is inserted into the casing. And a check valve that is a combination of and; a casing formed as a linear composition tube body with the member body fixed to the tension material head with the arrangement of the valve body opening end toward the casing drilling hole front end. In the state of close contact of the valve body with the casing inner surface in association with pressure injection from the opening end of the casing into the casing as a secondary injection at the time of removing the casing, the casing is disposed in the casing. Pull out at least the length of the single unit from the anchor hole, and remove the exposed single unit from the casing in order from the casing after the secondary injection of grout material is interrupted. Casing removal method for removing disconnected.

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