KR20160057844A - Grouting injection apparatus with backflow prevention, and grouting injection method using the same - Google Patents

Abstract

It is an object of the present invention to provide a grouting injection apparatus having a backflow prevention function and a grouting injection construction method using the apparatus and a grouting injection apparatus having a backflow prevention function according to a preferred embodiment of the present invention, And a first grouting agent is injected after excavation is completed; A plug portion disposed inside the outer tube for partially separating the excavated void space from the outer and inner tubings when the first grouting agent is injected, And an inner pipe having a perforated water discharge hole through which the perforated water is introduced and discharged to the outer pipe when the excavation hole is excavated and a second grouting agent is injected after the excavation is completed, And a space between the outer tube and the outer tube; And an upper block provided at an inner side of the inner tube and provided between an upper block block provided at an upper portion of the inner tube and a lower block provided at a lower portion of the inner tube, And a lower portion having a lower diameter than the inner diameter of the inner tube.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grouting injection apparatus having a backflow prevention function and a grouting injection method using the apparatus.

The present invention relates to a grouting injection apparatus and a grouting injection method using the apparatus, and more particularly, to a grouting injection apparatus having a backflow prevention function and a grouting injection method using the apparatus.

The grouting injection device is mainly used for stabilizing the ground, and is a device for performing grouting for the purpose of reinforcing the strength of the ground around the excavation hole or increasing the effect of the order of the ground around the excavation hole.

Various methods such as LW method, JSP method, Space Grouting Rocket System (SGR) method, MSG method, SCW method, and the like can be used as the grouting injection device according to the method. It is a well-known method so that detailed description of each of these methods is omitted.

Among these methods, there is an SGR method, and this SGR method will be described with reference to FIGS. 1 and 2. FIG.

Fig. 1 is a cross-sectional view showing an operation state of a conventional grouting injection apparatus during excavation, and Fig. 2 is a cross-sectional view showing an example of a grouting operation after completion of excavation in a conventional grouting injection apparatus.

Fig. 1 shows a state in which excavation is in progress, and Fig. 2 shows a state in which a normal grouting operation is performed after the excavation is completed.

1, a conventional grouting injection apparatus includes an excavating bit blade 23 attached to a lower end of an outer tube 20 for drilling, in order to form a drilling hole 6 on a ground 2, And the excavating bit 22 having the excavation bit 22 is provided.

The inner tube 10 is further provided inside the outer tube 20 and the inner tube 10 has a plug portion 12 for partially contacting the excavation bit 22 of the outer tube 20 to prevent further movement And the perforated water discharge holes 14-1, 14-2, and 14-3 that are discharged into the outer tube 20 when the drilled holes 6 are excavated.

The perforated water is supplied to the bottom surface 4 of the excavation hole 6 through the perforated water discharge holes 14-1, 14-2 and 14-3 during the excavation of the excavation hole 6, The cooling and lubrication action allows the excavating bit 22 to continuously excavate the excavation hole 6 and the drilling water contributing to the excavation can be transmitted through the bottom surface 4 of the excavation hole 6, 22 and the excavation surface serving as the wall surface of the excavation hole 6, and can be discharged to the outside through the outside of the outer tube 20. [

By repeating the excavation operation as described above, the excavation hole 6 having a predetermined depth can be formed, and the excavation hole 6 having reached the predetermined depth can be subjected to a grouting operation. This will be described with reference to Fig.

2, it can be seen that the outer tube 20 in the excavation hole 6 is in an upwardly raised state and the inner tube 10 is in a relatively lowered state.

At this time, the inner pipe 10 is not intentionally lowered, but rather is moved relative to the outer pipe 20 by raising the outer tube 20 on which the excavating bit 22 is mounted when the depth of the excavation hole 6 reaches a predetermined depth And the like.

It should therefore be noted that the inner tube 20 is located virtually adjacent to the bottom surface 4.

On the other hand, a grouting operation can be performed on the excavation surface of the excavation hole 6 (including the lateral direction and the downward surface in the drawing) in order to reinforce the strength of the surrounding ground or increase the effect of the order of the ground around the excavation hole 6.

A preparation step for carrying out the grouting work is shown in Fig.

At this time, the plug portion 12 formed on the outer side of the inner tube 10 contacts the portion of the excavating bit 22 fixed to the lowermost end of the outer tube 20, 40 and the lower part of the excavation hole 6 are substantially separated from each other. It should be noted that such a separation is useful for allowing the first grouting agent, which will be described later, to flow into the inner space 30 of the inner tube 10 through the through hole 16.

From Fig. 2, a first grouting agent, usually known as A solution, can be injected through the inner side of the inner tube 10 and the inner side of the outer tube 20. At this time, the first grouting agent flows into the inner tube 10 through the through-hole 16 as indicated by the arrow 42 in Fig.

At the same time, a second grouting agent, usually known as B solution, can be injected through the inner space 30 of the inner tube 10.

The first grouting agent and the second grouting agent introduced into the inner space 30 form a mixture liquid in a space immediately below the through hole 16 (not shown), while the grouting agent mixture is excavated along the direction of the arrow 45 And moves to the lower part of the hole (6).

The mixed liquid in which the first grouting agent and the second grouting agent are mixed is discharged into the excavation hole 6 through the plurality of perforated water discharge holes 14-1, 14-2, 14-3 formed in the lower portion of the inner pipe 10 And this flow is indicated by reference numeral 46.

The mixed liquid indicated by the reference numeral 46 is directly injected into the ground 2 through the excavation surface of the excavation hole 6 as shown by a wave pattern arrow shown in parallel to the horizontal plane of the excavation hole 6 in FIG. Respectively. 2, the injection of the grouting agent mixture into the ground 2 outside the excavation hole 6 is performed not only in the horizontal direction but also in the direction perpendicular to the bottom surface 4 of the excavation hole 6 Lt; / RTI >

Problems that may occur in the conventional SGR method as described above will be described in detail with reference to FIG.

Fig. 3 is a cross-sectional view showing a state in which backflow after the grouting operation is completed in the conventional grouting injection apparatus is started. Fig.

When it is judged from the grouting injection state shown in Fig. 2 that the initial grouting is finished, the supply pressure applied to the grouting mixture mixture of the first grouting agent and the second grouting agent injected into the ground 2 outside the excavation hole 6 Whereby the pressure which has been applied to the grouting agent mixture in the meantime acts in the opposite direction so that the direction of the perforated water discharge holes 14-1, 14-2 and 14-3 The flow of the backwash is displayed.

This backward flow (indicated by arrow 47) rises along the inner tube 10, and the upward backwash flow at this time is indicated by arrow 48.

The backwash flow (indicated by arrow 48) continues to rise and leaks into the space 40 between the inner tube 10 and the outer tube 20 through the through-hole 16 and even into the inner tube 10 And rose further along the space 30.

At this time, it is well known that the first grouting agent and the second grouting agent are not cured (or cemented) when they exist separately, and rapidly cure when they form a mixed solution.

Therefore, the grouting agent mixture flowing backward into the spaces 30 and 40 is hardened in these spaces 30 and 40, and there is a risk that these spaces 30 and 40 are blocked as they are.

In this case, if the grouting agent mixture liquid is hardened in the spaces 30 and 40, the first grouting agent and / or the second grouting agent are adversely affected in the process of further injection and subsequent work, The results showed that the effect of increasing the soil strength was not satisfactory, and that the grouting operation speed was too slow when the spaces (30, 40) were occluded frequently and the construction cost was increased. In addition, In some cases.

In order to suppress the clogging due to the backflow of the grouting agent mixture, water was injected through the inner tube and the inner tube during each step to perform cleaning. However, this operation itself was relatively difficult In addition, the groundwater is weakened by the water additionally injected, and the air is increased, resulting in an increase in the construction cost.

On the other hand, the hardening of the grouting solution can not be confirmed visually from the ground, and in order to solve such a problem in the present SGR method, the lower end of the inner tube 10 and / or the outer tube 20 It is a well-known fact that the tip is cut and discarded.

When the tip portion of the grouting apparatus is cut, the reliability of the mixing of the first grouting agent and the second grouting agent is lowered, and the backward flow of the impurities into the space between the inner tube 10 and the outer tube 20 So that the occlusion phenomenon may become more serious.

Therefore, it is possible to effectively prevent the backflow of the grouting agent mixture in the conventional SGR method as described above, and to prevent the backflow of the grouting agent mixture due to the backflow in the inner tube 10 and / or the space 40 between the outer tube 20 and the inner tube 10 It is necessary to avoid the hardening of the mixed solution, further increase the effect of the increase of the soil strength, or the effect of the geotechnical order, and reduce the construction cost by decreasing the air, and the inventors of the present invention have made the present invention after all efforts.

Korean Registered Patent No. 10-0815220 (the name of the invention: " a method of reinforcing the ground by injecting a soil strengthening agent with an injection device "), Mar. 19, 2008

It is an object of the present invention to provide a grouting injection apparatus having a backflow prevention function capable of solving the problem caused by the backflow of the grouting agent mixture in order to ensure the strength increase and the order effect of the ground around the excavation hole, And to provide a grouting injection method using the same.

It is to be understood that the subject matter of the present invention is not limited to the above-mentioned subject (s), and those skilled in the art will understand clearly the other subject (s) not mentioned in the following description It will be possible.

In order to solve the above problems, a grouting injection device having a backflow prevention function according to a preferred embodiment of the present invention is characterized in that the grouting injection device having the backflow prevention function has a drilling bit at the lowermost end, An outer surface to which the first grouting agent is injected; A plug portion disposed inside the outer tube for partially separating the excavated void space from the outer and inner tubings when the first grouting agent is injected, And an inner pipe having a perforated water discharge hole through which the perforated water is introduced and discharged to the outer pipe when the excavation hole is excavated and a second grouting agent is injected after the excavation is completed, And a space between the outer tube and the outer tube; And an upper block provided at an inner side of the inner tube and provided between an upper block block provided at an upper portion of the inner tube and a lower block provided at a lower portion of the inner tube, And a lower portion having a lower diameter than the inner diameter of the inner tube.

According to a preferred embodiment of the present invention, it is preferable that the upper portion of the piston and the lower portion of the piston have different diameters from each other.

The plurality of trough portions are separated from each other by a plurality of trough columns, and the plurality of trough portions and the plurality of trough columns are formed in the outer periphery of the lower portion of the piston, And extends along the entire height of the lower portion of the piston.

It is further preferable that mixing of the first grouting agent and the second grouting agent is performed in the vicinity of the upper portion of the piston.

Preferably, the width of the trough portion formed in the lower portion of the piston is shorter than the inner circumferential length of the lower blocking block formed along the inner circumference of the inner tube.

In addition, one or more recesses may be formed on the upper portion of the piston or the lower portion of the piston.

According to a preferred embodiment of the present invention, there is provided a grouting injection construction method using a grouting injection apparatus having a backflow prevention function of the above-described structure.

The details of other embodiments are included in the detailed description and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and / or features of the present invention and the manner of achieving them will be apparent from and elucidated with reference to the embodiments described hereinafter in conjunction with the accompanying drawings. However, it is to be understood that the invention is not limited to the disclosed embodiments, but may be embodied in many different forms and should not be construed as limited to the exemplary embodiments set forth herein. It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

It is to be understood that the same reference numerals refer to the same components throughout the specification and that the size, position, coupling relationship, etc. of each component constituting the invention may be exaggerated for clarity of description. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

According to the grouting apparatus having the backflow prevention function according to the present invention, it is possible to prevent the backflow of the grouting agent mixture liquid during the grouting operation, thereby preventing the grouting agent mixture liquid from hardening in the inner tube and / The working speed is increased, the construction cost is lowered, and the effect of the grounding order effect and the increase of the ground strength can be increased.

1 is a cross-sectional view showing an operating state during excavation of a conventional grouting injection apparatus.
2 is a cross-sectional view showing an example of a grouting operation after excavation is completed in a conventional grouting injection apparatus.
Fig. 3 is a cross-sectional view showing a state in which backflow after the grouting operation is completed in the conventional grouting injection apparatus is started. Fig.
FIG. 4 is a sectional view showing an example of a grouting operation after excavation is completed, showing a grouting injection apparatus having a backflow prevention function according to a preferred embodiment of the present invention. FIG.
FIG. 5 is a cross-sectional view illustrating a mechanism for preventing reverse flow after the grouting operation is completed, according to a preferred embodiment of the present invention.
6 is a cross-sectional view showing an AA section of a grouting injection apparatus having a backflow prevention function according to a preferred embodiment of the present invention shown in FIG.
FIG. 7 is a cross-sectional view showing a cross-sectional view of a BB of a grouting injection apparatus having a backflow prevention function according to a preferred embodiment of the present invention shown in FIG.
8A and 8B are cross-sectional views for explaining another embodiment of the structure of a piston constituting a grouting injection apparatus having a backflow prevention function according to a preferred embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

First, a grouting injection apparatus having a backflow prevention function according to a preferred embodiment of the present invention will be described with reference to FIG. 4, which is a sectional view showing an example of a grouting operation after excavation is completed.

FIG. 4 is a view similar to FIG. 1 to FIG. 3 for explaining the SGR method of the prior art. In FIGS. 4 to 8, It is to be understood that reference numerals and explanations for the respective reference numerals may be omitted.

4 shows that the second grouting agent is injected through the space 30 in the inner pipe 10 and the space 40 between the inner pipe 10 and the outer pipe 20 ), The manner in which the first grouting agent is injected is substantially the same as in the case of Fig. At this time, the flow of the second grouting agent is indicated by reference numeral 42.

4, the second grouting agent injected into the inside of the outer tube 20 and the outside of the inner tube 10 is injected into the inner tube 10 through the through hole 16 (see Figs. 1 and 2) At the instant of passing through the through-hole 16, with the first grouting agent being injected into the inner space 30 of the inner tube 10, at a position near the top of the piston, for example, It can be seen that the first and second grouting agents are mixed.

The first grouting agent and the second grouting agent mixture thus mixed are transported from the space 35 of the inner tube 10 to the lower portion of the drawing along the inner tube 10 at this time, So that it meets a piston (60).

An upper block block 50 provided on the upper side of the inner pipe 10 and a lower block block 55 provided on the lower side of the inner pipe 10 with the piston 60 therebetween.

The upper blocking block 50 will be described first.

It is preferable that the upper block 51 is set at the same height as the height of the upper surface 51 in the horizontal direction of the through hole 16. [

The upper blocking block 50 is configured to block the piston 60 from moving upward in the inner tube 10 and substantially preventing the piston 60 from rising past the through hole 16. [ Similarly, the lower blocking block 55 is configured to block the piston 60 from moving excessively in the downward direction within the inner tube 10. As shown in Fig.

The lower block 66 of the piston 60 can be easily passed though the upper block block 50 so that the upper portion 64 of the piston 60 can easily pass therethrough and move in the upper direction of the inner tube 10. [ It is desirable to have an inner diameter that is as low as possible.

To this end, the diameter of the upper portion 64 of the piston 60 is formed to be smaller than the inner diameter of the upper blocking block 50 while the lower portion 66 of the piston 60 passes through the upper blocking block 50, A lower inclined surface 52 is formed at the lower end of the upper block 50 so as not to pass through the upper portion of the upper block 10.

The inclined bottom inclined surface 52 is formed at an angle substantially equal to the angle of the upper inclined surface 62 connecting the upper portion 64 and the lower portion 66 of the piston 60.

These inclined lower inclined surface 52 and upper inclined surface 62 form a substantially shoulder portion (to be described later).

At this time, the inclination angles of the inclined lower end slope 52 and the upper slope 62 are not set to a specific angle because they can be formed at different angles when the first grouting agent and the second grouting agent are different.

For example, if the moving resistance of the mixed fluid of the first and second grouting agents is large, for example, the angle of the lower end slope 52 may be set to about 30 degrees.

It is also to be understood that the angle of the upper slope 62 may be set to 60 degrees if the movement resistance of the mixture of the first and second grouting agents is small.

The configurations of the inclined lower end slope 52 and the upper slope 62 will be described later in more detail.

The piston 60 is divided into an upper portion 64 and a lower portion 66 and is formed between the upper portion 64 and the lower portion 66 at an angle And an upper sloping surface 62 having a sloping surface 62a.

The upper portion 64 of the piston 60 is preferably formed to be smaller than the diameter of the lower portion 66 of the piston 60.

The upper portion 64 of the piston 60 is formed to be smaller in diameter than the inner diameter of the upper block 50 so that the upper portion 64 of the piston 60 is formed to pass through the upper block 50 and move to the upper portion of the inner pipe 10. [ do.

The lower end of the lower portion 66 of the piston 60 is caught by the lower blocking block 55 protruding from the inner side of the inner tube 10 toward the center of the inner tube 10 so that the lower end of the inner tube 10, As shown in FIG.

The lower blocking block 55 of the piston 60 is preferably formed to extend sufficiently long to the inside of the outer periphery of the lower end of the lower portion 66 of the piston 60, At least one, and preferably two or more, of them may be formed.

The lower blocking block 55 of the piston 60 does not need to have a particular geometric shape unlike the upper blocking block 50 of the piston 60 and the lower block 66 of the piston 60 is not limited to the inner tube 10 may be of a shape that can block the movement in the downward direction.

In other words, the piston 60 is arranged between the upper block block 50 and the lower block block 55, by the injection of the grouting agent mixture along the inner tube 10, to the lower portion, to the backflow pressure of the grouting agent mixture, So that it is configured to move upward.

4, the lower portion 66 of the piston 60 is in contact with the upper surface of the lower blocking block 55. As shown in FIG.

The lower portion 66 of the piston 60 may be provided with a plurality of groove portions 69 (see FIG. 6), which form a bypass through which the grouting mixture liquid passes along the outer side of the body.

It is to be understood that the mixed liquid of the first grouting agent and the second grouting agent mixed in the inner space 35 in the inner pipe 10 can be fed to the lower portion of the inner pipe 10 along the groove portion 69. [

It can be seen that the flow of the grouting liquid mixture at this time is shown as moving along the groove portion 69 formed on the outer peripheral surface of the lower portion 66 of the piston 60 as indicated by reference numeral 45-1 .

The grouting agent mixture pumped to the lower portion of the inner pipe 10 may be injected into the ground 2 or the like along the flow 46 as described with reference to Fig.

The configuration of the groove portion 69 formed in the piston 60 will be described with reference to Fig. 6 showing the cross section XX shown in Fig. 4. In addition, a part of the piston 60 described above The shape according to the embodiment will be described later with reference to Fig.

The situation at the time of injecting the grouting agent mixture corresponding to FIG. 2 has been described with reference to FIG. 4. Hereinafter, the situation at the time when the backflow of the grouting agent mixture starts corresponding to FIG. 3 5 will be described in more detail.

FIG. 5 is a cross-sectional view illustrating a mechanism for preventing reverse flow after the grouting operation is completed, according to a preferred embodiment of the present invention.

It can be seen from Fig. 5 that the piston 60 is moved in the upward direction inside the inner tube 10 by receiving the backward flow of the grouting agent mixture (indicated by the arrow 48).

When the grouting agent mixture flows backward, the piston 60 moves to the upper portion of the inner tube 10 and comes into contact with the sloping lower end inclined surface 52 of the upper blocking block 50. 5, the lower portion 66 of the piston 60 is separated from the lower blocking block 55 formed in the inner tube 10. As shown in Fig.

At this time, it should be noted that the most inclined surface of the upper inclined surface 62 of the piston 60 is in contact with the inclined lower inclined surface 52.

The specific mechanism of the abutment of the inclined upper surface 62 of the piston 60 and the inclined lower inclined surface 52 formed on the upper blocking block 50 will be described with reference to Fig. 7 showing the section YY of Fig. 5 Will be described later.

5, the upper portion 64 of the piston 60 passes through the inner diameter of the upper blocking block 50 and rises to the upper portion of the inner tube 10, The inclined surface of the upper inclined surface 62 of the piston 60 is inclined to the lower inclined surface 52 of the inclined surface 62 even when there is a flow 48 flowing backward because the inclined surface of the upper inclined surface 62 abuts the inclined lower inclined surface 52 The backflow to the upper portion of the inner tube 10 is effectively prevented.

The backward flow of the first grouting agent and the second grouting agent due to the abutment of the inclined lower surface 52 of the slope of the upper slope 62 of the piston 60 is blocked, 7 will be described later.

Next, with respect to the mechanism in which the mixed solution of the first grouting agent and the second grouting agent is injected into the lower portion of the inner tube 10, a sectional view (XX) of FIG. 4 showing a preferred embodiment of the present invention 6 will be described.

6 is a cross-sectional view showing an A-A cross-section of a grouting injection apparatus having a backflow prevention function according to a preferred embodiment of the present invention shown in FIG.

6, the piston 60 is caught by the lower block block 55 (indicated by a dotted line) inside the inner tube 10, and further movement of the piston 60 to the lower portion of the inner tube 10 is suppressed.

The upper part of the piston 60 passes through the inner diameter of the upper blocking block 50 formed in the inner tube 10 and is moved upward from the upper blocking block 50. [ It is preferable that the diameter is smaller than the diameter of the upper blocking block 50, preferably, the diameter of the upper blocking block 50 is substantially the same.

The height of the upper blocking block 50 may be appropriately longer than the height of the upper blocking block 50. The height of the upper blocking block 50 may be set to be less than the height of the lower blocking slope 52 formed at the lower end of the upper blocking block 50 It is preferable that the height is such that it does not collide with the surface of the substrate.

The upper portion 64 of the piston 60 and the lower portion 66 of the piston 60 are connected to an upper slope surface (of the piston 60) corresponding to the slope of the inclined lower slope surface 52 of the upper block 50 described above (Not shown).

The inclined angle of the inclined lower end inclined face 52 and the upper inclined face 62 need not be strictly defined but these groined faces abut against each other and flow backward through the upper portion 64 of the piston 60, The surface should be smoothly finished so that it does not flow past the upper blocking block 50 of the frame 10.

Alternatively, the piston 60 rises to the upper portion of the inner tube 10 by the reverse flow pressure generated by the reverse flow of the grouting agent mixture by forming concave and convex portions on the mutually abutting surfaces of the sloping lower end slope 52 and the upper slope 62 The lower inclined surface 52 and the upper inclined surface 62 may be formed to be engaged with each other, for example, as a gear engagement. It should be noted that the shape such as the gear engagement at this time includes meshing with each other by irregularities formed in a wavy shape in addition to the letter gear meshing. In other words, it should be understood that the combination of the inclined lower end inclined surface 52 and the upper inclined surface 62 includes engagement by irregularities formed separately from the engagement by these smooth inclined surfaces 52/62, even if it is any type of unevenness do.

Alternatively, a sealing ring or a rubber packing for sealing may be further provided on at least one side of the mutually abutting surfaces of the inclined lower end inclined surface 52 and the upper inclined surface 62.

These sealing rings and the rubber packing for sealing are preferably exchanged at appropriate intervals in consideration of wear.

6, a plurality of groove portions 69 may be formed in the lower portion 66 of the piston 60 along the outer periphery thereof.

At this time, the plurality of groove portions 69 each have a trough depth d, which is preferably formed on the inner side of the inner tube 10, and the lower portion of the piston 60, Is preferably formed to be deeper than the projecting height of the blocking block 55, but the groove depth d is not limited to this.

When a plurality of the groove portions 69 are formed on the outer periphery of the piston 60, a plurality of the groove portions 69 formed in the outer circumferential distance between the lower block block 55 and the lower block block 55 and the other groove portions 69 This is because the vertical posture of the piston 60 can be maintained only if the gutter column 68 is seated on at least one of the lower blocking blocks 55.

Therefore, it will be appreciated that the groove depth d can be appropriately formed by those having ordinary skill in the art.

However, the width of each of the groove portions 69 formed along the outer circumferential direction of the lower portion 66 of the piston 60 is set to be smaller than the width of each of the groove portions 69 of the lower block portion 66, It is preferable that the width of the piston 60 is smaller than the width of the lower blocking block 55 so that the piston 60 can be brought into contact with at least one of the upper block 55 and the lower block 55.

That is, the width of the trough formed at the lower portion of the piston, that is, the width of the trough formed along the outside of the lower portion of the piston is preferably shorter than the inner circumferential length of the lower blocking block formed along the inner circumference of the inner tube.

In Fig. 6, reference numeral 67 denotes the bottom of the groove portion 69, and as described above, it is sufficient that the groove bottom portion 67 is formed of a bottom having an appropriate groove depth d.

Here, the piston 60 may be formed of metal or plastic, and may have the same specific gravity as the specific gravity of the first grouting agent and / or the second grouting agent, or the grouting agent mixture in which the first grouting agent and the second grouting agent are mixed, or It is preferable to be formed of at least one material having a lower specific gravity, for example, aluminum, plastic, or ceramic.

Alternatively, the specific gravity of the piston 60 itself may be lowered by forming a hollow in the upper portion 64 and / or the lower portion 66 of the piston 60, which will be further described with reference to FIG.

In other words, the piston 60 is quickly moved to the lower portion of the pipe 10 by the injection flow of the first grouting agent and / or the second grouting agent or the grouting agent mixture, So as to have a specific gravity capable of moving to the upper portion of the inner tube 10.

The material of the trough column 68 formed in the lower portion 66 of the piston 60 may be formed of a material different from the material of the lower portion 66 of the piston 60. [ For example, when the lower portion 66 of the piston 60 is made of aluminum, the material of the trough column 68 can be formed of a synthetic resin including engineering plastics.

In this case, the maximum height of the trough column 68 is set to be the same as the height of the upper inclined surface 62 in consideration of the contact impact with the inclined lower end inclined surface 52 of the upper block block 52 while being the uppermost end of the trough column 68. [ May be formed lower than the height.

At this time, as the material forming the lower portion 66 of the piston 60, it is possible to repel the first grouting agent and / or the second grouting agent or the grouting agent mixture, that is, the grouting agent and / It is preferable that the piston 60 is formed of a material which does not stick to the surface of the lower portion 66 of the piston 60, for example, a material having properties similar to those of materials having hydrophobic properties to water.

In the case of such a hydrophobic material, since the grouting agent mixture is repelled from the surface of the material, it is very advantageous in terms of maintenance.

Next, referring to Fig. 7 (and also at the same time in Fig. 5), when the piston 60 rises upward from the inside of the inner tube 10 by the reverse flow of the grouting agent mixture and the reverse flow at this time, A mechanism for effectively preventing backflow of the grouting agent mixture by abutting the upper inclined surface 62 and the inclined lower inclined surface 52 of the upper blocking block 50 will be described.

FIG. 7 is a cross-sectional view showing a B-B cross section of a grouting injection apparatus having a backflow prevention function according to a preferred embodiment of the present invention shown in FIG.

7, the piston 60 rises to the upper portion of the inner tube 10 by the back flow (pressure) of the grouting agent mixture, whereby the upper portion 64 of the piston 60 is moved upward to the upper block 50, As shown in Fig. It should be noted that in Fig. 7, the configurations of the upper block 50 shown in Figs. 3 and 4 and the plurality of troughs 69 and / or trough columns 68 shown in Fig. 6 are not shown .

The upper portion 64 of the piston 60 protrudes upward into the space 35 and at the same time the upper inclined surface 62 of the piston 60 and the inclined lower end of the upper blocking block 50 The inclined surfaces 52 are in contact with each other to form contact lines 52/62. It will be appreciated that the contact line 52/62 at this time is centered along the upper sloping surface 62 of the piston 60.

In FIG. 7, reference numeral 62 'denotes a shoulder in which the upper inclined surface 62 of the piston 60 and the inclined lower end inclined surface 52 of the upper blocking block 50 are in contact with each other. The upper shoulder portion 62 'of the piston 60 is formed by abutting against the upper inclined surface 62 of the piston 60 and the inclined lower end inclined surface 52 of the upper blocking block 50. As described above, It is desirable to understand that the grouting agent mixture for preventing the backflow or leaking of the grouting agent mixture further flows.

The shoulder 62 'preferably extends from the outer periphery of the lower portion 66 of the piston 60 to the lower neck of the upper portion 64 of the piston 60, as shown. At this time, when the shoulder portion 62 'is formed in close contact with the neck bottom of the upper portion 64 of the piston 60, the upper portion 64 of the piston 60 maintains a vertical state in the upper blocking block 50 There is a possibility that the upper sloping face 62 of the piston 60 and the sloping lower end sloping face 52 of the upper blocking block 50 are not effectively brought into contact with each other. Extending from the outer periphery of the lower portion 66 of the piston 60 to just before the neck bottom of the upper portion 64 of the piston 60.

In the figure, the shoulder portion 62 'is shown extending from the outer periphery of the lower portion 66 of the piston 60, but as described above, the plurality of groove portions 69 and / It is to be understood that the case of extending from the outer periphery of the lower portion 66 of the piston 60 shows a portion where the trough column 68 is formed.

If the shoulder portion 62 'starts from the plurality of groove portions 69, the extension length of the shoulder portion 62' will be shortened. In this case, even if the shoulder portion 62 'is shortened, as shown in Fig. 4, the groove depth d (see Fig. 6) of the groove portion 69 is not longer than the extension length of the shoulder portion 62' It is preferable to form the grouting mixture mixture rising due to the back flow so as not to flow back or leak to the upper portion of the inner tube 10 through the shoulder portion 62 ', specifically, the groove portion 69 .

Another embodiment of the piston 60 will be described with reference to Fig.

8 (a) and 8 (b) are cross-sectional views for explaining another embodiment of the configuration of a piston constituting a grouting injection apparatus having a backflow prevention function according to a preferred embodiment of the present invention.

8 (a), a concave portion 61 is formed in the upper portion 64 of the piston 60. As shown in Fig.

When the grouting mixture mixed with the first grouting agent and / or the second grouting agent, preferably the first grouting agent and the second grouting agent is fed to the lower portion of the inner tube 10, So that the piston 60 can be received in the lower blocking block 55 more quickly. For this purpose, it is also possible to form a plurality of perforations (not shown) on the outer circumference of the concave portion 61 in order to prevent the grouting agent mixture from staying in the concave portion 61. In this case, the depth of the concave portion 61 formed in the upper portion 64 of the piston 60 need not be deep. The shape of the concave portion 61 is not limited to a quadrangle, Or the like.

8 (b), the concave portion 61 may be formed on the upper portion of the piston 60, and another concave portion 63 may be formed on the lower portion 66 of the piston 60.

In the case of the concave portion 63, it is preferable to form the concave portion 63 in consideration of the groove depth d of the groove portion 69 when the lower portion 66 of the piston 60 is integrally formed would. It will be appreciated that the recess 63 is configured to quickly receive the backflow pressure when the grouting agent mixture flows backward and to rapidly move the piston 60 to the upper portion of the inner tube 10. [

At this time, as described above, the outer surface of the piston 60 may be made of a material capable of bouncing or at least not reacting with the first grouting agent and / or the second grouting agent and / or the grouting agent mixture .

It will also be appreciated that the recesses 61 and / or recesses 63 may also control the specific gravity of the piston 60, as described above.

That is, by forming at least one of the concave portion 61 and / or the concave portion 63, the specific gravity can be greatly reduced or not formed, and a specific gravity similar to the specific gravity of the grouting or grouting mixture can be formed You may.

Finally, the upper blocking block 50, the lower blocking block 55, and the plug portion 12 provided in the inner tube 10 are easily attached to the inner tube 10 by screwing (not shown) And it is determined that the forming position and the forming method of the screw coupling portion can be easily formed by those having ordinary skill in the art, The description will be omitted.

Hereinafter, a construction method of a grouting injection apparatus having a backflow prevention function according to a preferred embodiment of the present invention will be briefly described.

The first grouting agent injected through the inner tube 10 and the outer tube 20 and / or the second grouting agent injected through the inner tube 10 are mixed in the space 35 near the upper block 50, As shown in FIG. 4, the piston 60 moves to the lower portion of the inner tube 10 and is caught by the lower blocking block 55 by the injection pressure at this time.

At this time, the grouting agent mixture is continuously fed to the lower portion of the piston 60 through the plurality of groove portions 69 formed along the outer surface of the lower portion 66 of the piston 60.

5, the piston 60 is caused to rise toward the upper portion of the inner tube 10 by the backflow pressure, and the upward movement of the piston 60 is transmitted to the upper inclined surface (the upper surface) of the piston 60 62 are abutted against the sloping lower end inclined surface 52 formed at the lower portion of the upper blocking block 50 and blocked.

As a result of this blockage, leakage of the grouting agent mixture in the reverse flow can be effectively prevented.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, You will know well. Accordingly, the spirit of the present invention should not be construed as being limited to the embodiments included in the above description, but should be determined only by the claims of the following claims, and all modifications equivalent or equivalent to the claims of the claims .

2: Ground
4: bottom surface
6: Excavation Balls
10: Inner pipe
12: Plug section
14-1: Perforated drain hole
14-2: Perforated drain hole
14-3: Perforated drain hole
16: Through hole
18:
20: Appearance
22: Drill bit
23: Drill bit blade
30: Space
40: Space
50: upper blocking block
52: inclined bottom slope
55: Lower block
60: Piston
61:
62: Upper slope
62 ': Shoulder portion
63:
64: upper (of piston)
66: Lower (of piston)
68: Lead column
69:
d: Depth of recess

Claims (7)

An outer pipe having a drilling bit at the lowermost end and a first grouting agent being injected after the excavation is completed;
A plug portion disposed inside the outer tube for partially separating the excavated void space from the outer and inner tubings when the first grouting agent is injected, And an inner pipe having a perforated water discharge hole through which the perforated water is introduced and discharged to the outer pipe when the excavation hole is excavated and a second grouting agent is injected after the excavation is completed, And a space between the outer tube and the outer tube; And
An upper block having an inner diameter smaller than an inner diameter of the upper block, and a lower block disposed between the upper block and the lower block, the upper block having an inner diameter smaller than the inner diameter of the upper block, And a lower portion having a lower diameter than an inner diameter of the inner pipe.
A grouting injection device having a backflow prevention function.
The method according to claim 1,
Characterized in that the upper part of the piston and the lower part of the piston are different in diameter from each other,
A grouting injection device having a backflow prevention function.
3. The method of claim 2,
Wherein a plurality of trough portions are formed by a plurality of trough columns separately, and the plurality of trough portions and the plurality of trough columns are formed in a circumferential direction of the piston And extends along the entire height of the lower portion.
A grouting injection device having a backflow prevention function.
The method according to claim 1,
Wherein the mixing of the first grouting agent and the second grouting agent is performed in the vicinity of the upper portion of the piston.
A grouting injection device having a backflow prevention function.
The method according to claim 1,
Wherein a width of the trough portion formed in the lower portion of the piston is shorter than an inner circumferential length of the lower blocking block formed along the inner circumference of the inner tube.
A grouting injection device having a backflow prevention function.
The method according to claim 1,
Characterized in that one or more recesses are formed in the upper part of the piston or in the lower part of the piston.
A grouting injection device having a backflow prevention function.
A grouting injection method using a grouting injection device having a backflow prevention function according to any one of claims 1 to 6.

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