JP4755130B2 - Reinforcing tool and ground reinforcement method - Google Patents

Description

  The present invention relates to a reinforcing tool and a natural ground reinforcing method.

  Conventionally, when tunnels are dug in the ground of urban areas and fragile grounds of mountainous areas, reinforcements of natural ground have been performed using reinforcing materials such as rods and tubes. Reinforcement methods include: (1) Drilling a hole in the ground and inserting a reinforcing material, installing a packer at the drilled mouth, and injecting an injection material into the space between the reinforcing material and the ground, The method of integrating the natural ground was common.

If the ground is fragile and the drilled hole is rough or collapsed, it will be impossible to insert the reinforcing material manually. Drilling the ground reinforcement and inserting the rod-shaped reinforcement, and then pulling out the casing tube from the hole, injecting the injection material into the space between the reinforcement and the ground, and integrating the reinforcement and the ground There was also a way to make it.
Alternatively, (3) there is a method in which the reinforcing material is used as a casing pipe of a double pipe drilling hole, and the reinforcing material and the natural ground are integrated by injecting the injecting material from the inside of the pipe (for example, Patent Document 1). reference).

(4) Drilling using the reinforcing material as a rod, using the reinforcing material itself as an injection pipe, injecting the injected material into the space between the reinforcing material and the natural ground, and integrating the reinforcing material and the natural ground There was also a method (see, for example, Patent Document 2).
As a special method, there was a method of (5) inserting a metallic tube material into a hole, expanding it with an extremely high pressure to expand the natural ground, and making contact with the natural ground (for example, patent document) 3).

Patent Publication No. 2955279 JP 9-184400 A JP 2004-19359 A

  In the natural ground reinforcement method using a reinforcing material, it is advantageous in terms of construction to insert a reinforcing material that is as long as possible at a time, because the seam that becomes a weak part can be reduced and the construction cycle can be accelerated. However, in the method (1), the longer the boring distance is, the more easily the hole is bent, so that it is difficult to insert the reinforcing material later. Moreover, when the natural ground is fragile, hole roughening or hole collapse is likely to occur, and it is difficult to post-insert a long reinforcing material.

  The methods (2) and (3) solve the problem that the reinforcing material cannot be inserted afterward due to bending of the hole, roughing of the hole or collapse of the hole by protecting the hole wall using the casing tube. However, in the method (2), the casing needs to be removed, so that there is a problem that the process loss is large, and the high cost due to the use of a dedicated machine is also a problem. Further, in the methods (2) and (3), a casing pipe having a relatively flat outer peripheral surface is often used in order to make a hole smoothly, but the reinforcing material having a flat outer peripheral surface by the method (3). Is used as a casing tube, there is a problem that the peripheral friction exhibited when the reinforcing material is fixed by injecting the injection material into the gap with the natural ground is reduced.

The method (4) is easy to insert into the hole because the general diameter of the reinforcing material is as small as about φ32 mm. However, since the diameter is small, there is a problem that the tensile strength of the reinforcing material is insufficient and the expected peripheral friction is also small.
In addition, any of (1) to (4) includes a step of injecting an injection material between the natural ground and the reinforcement material after the reinforcement material is inserted into the hole. The increase is inevitable and the influence of the injected material on the surrounding environment cannot be ignored.

  Since the method (5) does not use an injection material, it can solve the problems caused by the step of injecting the injection material between the ground and the reinforcing material. However, the work is very dangerous due to the use of high pressure, and since the reinforcing material is made of metal, workability is greatly deteriorated when excavation of natural ground is necessary after reinforcement. Even if peripheral friction cannot be expected due to the nature of the water in the hole or the natural ground, there is a problem that post-reinforcement with an injecting material is impossible, and it is hardly used in practice.

  The present invention has been made in view of such problems, and the object of the present invention is that it can be easily inserted into a hole excavated in a natural ground, and a large frictional force can be expected between the natural ground and an injection material. It is an object of the present invention to provide a reinforcing tool and a natural ground reinforcing method capable of omitting the step of injecting.

  A first invention for achieving the above-mentioned object has a main body formed of a thermoplastic resin as a base material and reinforced in the axial direction with continuous fibers which are tubular woven fabrics. The main body is heated and heated. The reinforcing tool is characterized in that when it is pressed, it expands to increase the area occupied by the cross section.

  The continuous fiber which is a tubular woven fabric has elongation in the radial direction. If necessary, the reinforcing tool is provided with a restraining portion on a part of the main body before being heated and pressurized, and the main body is uneven when heated and pressurized. The body may have a hole on the side. In addition, there may be a drilling tool at the tip. The main body does not have a joint portion. When the main body is directly heated / pressurized, the side holes are closed until the inside of the main body reaches a predetermined pressure, and are opened when the pressure exceeds the predetermined pressure.

  According to a second aspect of the present invention, the reinforcing tool of the first aspect of the invention is inserted into a hole formed in a natural ground, and then the main body is heated and pressurized to expand, thereby expanding the occupied area of the cross section. This is a mountain reinforcement method.

3rd invention inserts the reinforcing tool of 1st invention which has a hole in the side part of a main body in the hole formed in the natural ground, and expands the said main body by heating and pressurizing, The step (b) of expanding the occupation area of the cross section, and injecting the injection material from the inside of the main body, the injection material is formed in the natural ground through the hole provided in the side portion of the main body And a step (c) of injecting into the inside of the hole.

  The reinforcing tool may be one in which a restraint portion is provided in a part of the main body before heating and pressurizing, and the surface of the main body becomes uneven when heated and pressed. In the step (c), in some cases, an injection material is also injected into the natural ground around the hole.

In 3rd invention, it is desirable to install a bag body in a reinforcement tool at a process (a) and to heat a main body from the inside of a bag body at a process (b). Further, it is desirable that an elastic member is attached to the outer peripheral portion of the mouth side of the reinforcing tool, and in step (b), the elastic member is pressed against the natural ground as the main body expands.

In the third invention, the main body may be directly heated and pressurized in the step (b). At this time, in the step (b), the hole in the side part of the main body is closed until the inside of the main body reaches a predetermined pressure, and is opened when the pressure exceeds the predetermined pressure.

  According to the present invention, it is easy to insert into a hole excavated in a natural ground, a large frictional force can be expected between the natural ground, and a reinforcing tool and a natural ground reinforcing method capable of omitting the step of injecting an injection material Can provide.

  Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view of the reinforcing tool 1. 1A is a perspective view of the reinforcing tool 1a before heating / pressing, FIG. 1B is a perspective view of the reinforcing tool 1b before heating / pressing, and FIG. 1C. FIG. 1 is a perspective view of the reinforcing tool 1a after heating / pressing, and FIG. 1 (d) is a perspective view of the reinforcing tool 1b after heating / pressing.

As shown in (a) of FIG. 1, the reinforcing member 1a, the body 2a is a tubular member, the cross-section 3a ₁ of the heat-pressurization is C-shaped. Both ends of the reinforcing tool 1a are open surfaces. The reinforcing tool 1a is formed by using a thermoplastic resin as a base material and including continuous fibers that are tubular woven fabrics.

Body 2a of brace 1a is to expand when heated and pressurized, cross section 3a _2, and the substantially the cross-section 3a ₁ shown in (a) of FIG. 1 is shown in (c) diagram of Figure 1 The occupied area, that is, the area surrounded by the dotted line 5a increases. Body 2a of brace 1a is cross-section 3a ₂ of the heating and after pressurization is substantially circular.

As shown in (b) diagram of Figure 1, the brace 1b is a member of the body 2b is tubular, cross-section 3b ₁ of the heat-pressurization is substantially circular. Both ends of the reinforcing tool 1b are open surfaces. The reinforcing tool 1b is formed by using a thermoplastic resin as a base material and including continuous fibers that are tubular woven fabrics.

Body 2b of the brace 1b is to expand when heated and pressurized, cross section 3b _2, and the substantially the cross section 3b ₁ shown in (b) diagram of Figure 1 is shown in (d) of Figure of Figure 1 The occupied area, that is, the area surrounded by the dotted line 5b increases. Body 2b of the brace 1b is cross section 3b ₂ of the heating and after pressurization also becomes substantially circular.

As described above, the reinforcing tool 1 shown in FIG. 1 is formed to include a continuous fiber that is a tubular woven fabric using a thermoplastic resin as a base material. The cylindrical woven fabric is a woven fabric that is formed into a cylindrical shape by vertically crossing an axial warp and a weft in a radial direction, and is woven by an annular loom or the like. In the reinforcing tool 1, the axial rigidity is reinforced by the fibers in the axial direction (the direction indicated by the arrow A in the drawing) of the tubular woven fabric. Further, the radial fibers prevent the continuous fibers in the axial direction from being separated by shearing, thickness unevenness does not occur during expansion, and the resistance to shearing is enhanced. As a result, uniform expansion in the radial direction can be achieved.

In order to produce the reinforcing tool 1a, first, a member formed into a shape as shown in FIG. 1 (c) is produced. Thereafter, the body 2a is softened by heating, as shown in (a) of FIG. 1, is deformed so as to substantially occupied area of the cross section 3a ₁ is reduced.

In order to produce the reinforcing tool 1b, first, a tubular woven fabric is produced using a weft having an elongation that can be deformed into a shape as shown in FIG. Produces molded parts. As shown in FIG. 1B, the substantial occupation area of the cross section 3b ₁ is smaller than the substantial occupation area of the cross section 3b ₂ shown in FIG.

Furthermore, it is also possible to produce a tubular woven fabric having the features described in [0025] and [0026]. In that case, the occupation area is further increased than the reinforcing tools 1a and 1b by heating and pressing. Can do.

  FIG. 2 is a cross-sectional view of the natural ground 9 reinforced with the reinforcing tool 1. In the first embodiment, as shown in FIG. 2, the natural ground 9 in front of the face 13 of the tunnel 11 being excavated is replaced by the reinforcing tool 1 (either the reinforcing tool 1a or the reinforcing tool 1b shown in FIG. 1). Reinforce with

FIG. 3 is a cross-sectional view of the reinforcing tool 1 in the axial direction, and FIG. 4 is a diagram showing each process when reinforcing the natural ground 9 using the reinforcing tool 1. FIG. 4A is a diagram showing a process of drilling holes 15 in the natural ground 9. In the first embodiment, first, as shown in FIG. 4A, a hole 15 is drilled in the natural ground 9 from the face 13 of the tunnel 11 toward the front. Drilling is carried out by a conventional method using a rock drill or the like.

As shown in FIG. 3, the reinforcing tool 1 has a bag 33 disposed in the inside 7. The bag 33 is disposed in the inner part 7a in the reinforcing tool 1a shown in FIG. 1 (a) and in the inner part 7b in the reinforcing tool 1b shown in FIG. 1 (b). The bag body 33 is closed at the distal end 17 side of the reinforcing tool 1 and opened at the mouth 29 side of the reinforcing tool 1. The bag 33 is arranged so that the end portion 35 protrudes from the mouth 29 side of the reinforcing tool 1.

FIG. 4B is a diagram illustrating a process of inserting the reinforcing tool 1 into the hole 15. After drilling the hole 15 in the ground 9, the reinforcing tool 1 is inserted into the hole 15 as shown in FIG. The reinforcing tool 1 is inserted manually so that the mouth 29 is located near the entrance of the hole 15. The end portion 35 of the bag body 33 is disposed behind the face 13.

  FIG. 4C is a diagram illustrating a process of mounting the pressurizing socket 37. After inserting the reinforcing tool 1 into the hole 15, a pressurizing socket 37 is attached to the end portion 35 of the bag 33 as shown in FIG.

  FIG. 4D is a diagram showing a step of expanding the reinforcing tool 1. After mounting the pressurizing socket 37, the reinforcing tool 1 is heated and pressurized from the inside of the bag 33 using the pressurizing socket 37 as shown in FIG. 4 (d). The reinforcing tool 1 expands when heated and pressurized, and the occupied area of the cross section 3 (FIG. 1 (c)) increases. The expanded reinforcing tool 1 has a substantially occupied area of the cross section 3 substantially equal to the cross sectional area of the hole 15. At this time, due to the expansion of the reinforcing tool 1, the diameter of the hole 15 may be larger than that during drilling.

In the reinforcing tool 1, the diameter of the resin in the radial direction of the tubular fabric increases as the thermoplastic resin that is the base material expands. Moreover, the reinforcing tool 1 using a thermoplastic resin can be deformed into a shape different from the shape initially formed when the reinforcing tool 1 is manufactured by increasing the pressure. Therefore, the diameter of the hole 15 is deformed to a larger diameter than the initially formed diameter, the inner surface of the hole 15 is pressed by the effect, and the diameter of the hole 15 is further increased. Is possible. In the first embodiment, as shown in FIG. 4D, the reinforcing tool 1 is deformed following the unevenness of the wall surface of the hole 15.

The reinforcing tool 1 is softened when heated and has a shape and a state left to its own weight. In the step shown in FIG. 4D, the reinforcing tool 1 is heated and pressurized to expand to a predetermined shape, and then cooled and cured while maintaining the pressure and shape of the inside 7. During cooling, cooling water or cooling air is injected into the bag 33. The thermoplastic resin can retain its shape even after normal curing after curing.

FIG. 4E is a diagram illustrating a process of removing the bag 33. After the reinforcing tool 1 is cured in the expanded state, the bag 33 in the reinforcing tool 1 is removed as shown in FIG.
The reinforcing tool 1 can be directly heated and pressurized from the inside by directly attaching a pressurizing socket to the mouth 29. In this case, cooling after expansion is performed by directly injecting cooling water or the like into the inside.

  As described above, in the first embodiment, the reinforcing tool 1 is inserted into the hole 15 in a state where the occupied area of the cross section is small as shown in FIG. A hole longer than various conventional reinforcing materials can be inserted into the hole. Further, the reinforcing tool 1 using a thermoplastic resin can be easily cut when the tunnel 11 is further excavated from the state shown in FIG.

In the first embodiment, by deforming the reinforcing tool 1 following the unevenness of the wall surface of the hole 15, the reinforcing tool 1 bites into the fine unevenness of the natural ground 9 and becomes difficult to slip, and the axial load is rapidly increased. Is transmitted to natural ground 9. Moreover, the process which inject | pours an injection material between the reinforcement tool 1 and the natural ground 9 can be skipped by sticking the reinforcing material 1 to the natural ground 9. Furthermore, since the reinforcing tool 1 can be deformed into a shape different from the shape first formed, the reinforcing tool 1 can be securely brought into close contact with the natural ground 9.

  Since the thermoplastic resin that is the base material of the reinforcing tool 1 can be expanded or deformed with a relatively small force when softened by heating, a machine that applies high pressure is not required. Therefore, the reinforcing tool 1 can be safely expanded as compared with the conventional method of expanding a metal pipe using high pressure.

  Next, a second embodiment will be described. FIG. 5 is a perspective view of the reinforcing tool 1c. 5A is a perspective view of the reinforcing tool 1c before heating / pressing, and FIG. 5B is a perspective view of the reinforcing tool 1c after heating / pressing.

As shown in (a) of FIG. 5, the brace 1c is a member of the body 2c has a tubular cross section 3c ₁ of heating and pressurization is substantially circular. Both ends of the reinforcing tool 1c are open surfaces. The reinforcing tool 1c is formed by using a thermoplastic resin as a base material and including continuous fibers that are tubular woven fabrics. The reinforcing tool 1c has a hole 21 in a side portion of the main body 2c.

In addition, when using the reinforcing tool 1c for natural ground reinforcement, the seal 31 (FIG. 6) is attached to the outer periphery on the mouth 29 side. The seal 31 (FIG. 6) is an elastic member such as rubber, for example.

Body 2c of the reinforcing member 1c is to expand when heated and pressed, transverse section 3c _2, and the substantially the cross-section 3c ₁ shown in (a) of FIG. 5 is shown in (b) diagram of Figure 5 Occupied area increases. Body 2c of the reinforcing member 1c is cross section 3c ₂ of the heating and after pressurization also becomes substantially circular.

As in the reinforcing tool 1 shown in FIG. 1, the reinforcing tool 1 c has axial rigidity enhanced by axial fibers in the tubular fabric. Further, the radial fibers prevent the continuous fibers in the axial direction from being separated by shearing, and the resistance to shearing is enhanced. The tubular fabric has an elongation in the radial direction. In the reinforcing tool 1c, the diameter of the fiber in the radial direction of the tubular fabric increases as the thermoplastic resin as the base material expands.

In order to produce the reinforcing tool 1c, first, a member molded into a shape as shown in FIG. 5B is produced. Thereafter, the main body 2c is softened by heating, as shown in (a) of FIG. 5, is deformed so as to substantially occupied area of the cross section 3c ₁ is reduced. Alternatively, a tubular woven fabric is produced using a weft having an expandable elongation in a shape as shown in FIG. 5B, and a member molded using the substantially tubular woven fabric is produced.

Furthermore, it is also possible to produce a tubular woven fabric having the features described in [0045]. In this case, the occupation area can be further increased by heating and pressurization than the reinforcing tool 1c.

FIG. 6 is a diagram showing each step when reinforcing the natural ground 9 using the reinforcing tool 1c. In 2nd Embodiment, as shown in FIG. 6, the natural ground 9 ahead of the face 13 of the tunnel 11 under excavation is reinforced using the reinforcement tool 1c.

FIG. 6A is a diagram showing a process of drilling the hole 15 in the natural ground 9 and inserting the reinforcing tool 1c. In the second embodiment, first, a hole 15 is drilled in the natural ground 9 from the face 13 of the tunnel 11 toward the front. Drilling is carried out by a conventional method using a rock drill or the like.

After drilling the hole 15 in the ground 9, the reinforcing tool 1 c is inserted into the hole 15, and the seal 31 is attached to the mouth 29. The reinforcing tool 1c is manually inserted so that the mouth 29 is located near the entrance of the hole 15. In addition, the bag body 33 (not shown) is arrange | positioned like the reinforcement tool 1 shown in FIG. 3 at the inside 7c of the reinforcement tool 1c. After inserting the reinforcing tool 1 into the hole 15, a pressurizing socket 37 (not shown) is attached to the end portion 35 of the bag body 33 as in the step shown in FIG.

  FIG. 6B is a diagram showing a process of inflating the reinforcing tool 1c and injecting the injection material 19. In the step shown in FIG. 6 (b), the reinforcing tool 1c is heated and pressurized from the inside of the bag 33 (not shown) using a pressurizing socket 37 (not shown), and FIG. 5 (b). Expand to the state shown in the figure. The expanded reinforcing tool 1 c has a substantially occupied area in the cross section substantially equal to the cross-sectional area of the hole 15. At this time, the diameter of the hole 15 may become larger than that at the time of drilling due to the expansion of the reinforcing tool 1c. The seal 31 attached to the mouth 29 of the reinforcing member 1 c increases in diameter as the main body 2 c of the reinforcing member 1 c expands and is pressed against the wall surface of the hole 15. However, regarding the seal 31 between the reinforcing tool 1c and the natural ground 9 at the mouth 29, it is not necessary to use an elastic member, and a seal with urethane may be used as in the related art.

In the second embodiment, it is not necessary for the reinforcing member 1c to follow the unevenness of the wall surface of the hole 15. In the step shown in FIG. 6B, after the reinforcing tool 1c is expanded to a predetermined shape, it is cooled and cured while maintaining the pressure and shape of the interior 7c.

  After the reinforcing tool 1c is cured, the bag body 33 (FIG. 4D) in the reinforcing tool 1c is removed. Then, an injection tube and a packer (not shown) are installed on the mouth 29 side of the inside 7c of the reinforcing tool 1c, and the injection material 19 is injected. The seal 31 prevents the injection material 19 from leaking into the tunnel 11. The injection material 19 is filled into the hole 15 through the hole 21.

  As described above, in the second embodiment, the reinforcing tool 1c is inserted into the hole 15 with a small cross-sectional area as shown in FIG. A hole longer than various conventional reinforcing materials can be inserted into the hole. Further, the reinforcing tool 1c using a thermoplastic resin can be easily cut when the tunnel 11 is further excavated from the state shown in FIG. 6 (b).

  The thermoplastic resin that is the base material of the reinforcing tool 1c can be expanded or deformed with a relatively small force when softened by heating, and therefore does not require a machine that applies high pressure. Therefore, the reinforcing tool 1c can be safely expanded as compared with the conventional method of expanding a metal pipe using high pressure.

In the second embodiment, by injecting the injection material 19 into the hole 15, circumferential friction due to adhesion between the unevenness of the ground 9 and the injection material 19 can be expected.

  Next, a third embodiment will be described. FIG. 7 shows a perspective view of the reinforcing tool 1d. 7A is a perspective view of the reinforcing tool 1d before heating / pressing, and FIG. 7B is a perspective view of the reinforcing tool 1d after heating / pressing.

As shown in (a) of FIG. 7, brace 1d is a member of the body 2d is tubular, cross-section 3d ₁ of heating and pressurization is substantially circular. Both ends of the reinforcing tool 1d are open surfaces. The reinforcing tool 1d is formed by using a thermoplastic resin as a base material and including continuous fibers that are tubular woven fabrics. The reinforcing tool 1d has a hole 21 in a side portion of the main body 2d.

When the reinforcing tool 1d is used for natural ground reinforcement, a seal 31 (FIG. 8) is attached to the outer periphery on the mouth 29 side. The seal 31 (FIG. 8) is an elastic member such as rubber. Furthermore, a radial restraint 25 (FIG. 8) is provided on a part of the main body 2d. The restraining part 25 (FIG. 8) is provided avoiding the position of the hole 21.

As shown in FIG. 7B, when the body 2d of the reinforcing tool 1d is heated and pressurized, the main body 2d expands to have different diameters in the portion restrained by the restraining portion 25 and the portion not restrained. Unevenness occurs on the surface. Body 2d of brace 1d, when heated, the portion not constrained cross section 3d ₂ next to cross-section 3d ₁ shown in (a) of FIG. 7 is shown in (b) diagram of Figure 7, substantially Occupies a large area. Cross section 3d ₂ heating and after pressing of the body 2d of brace 1d becomes substantially circular.

Similar to the reinforcing tool 1 shown in FIG. 1, the reinforcing tool 1 d has axial rigidity enhanced by axial fibers in the tubular fabric. Further, the radial fibers prevent the continuous fibers in the axial direction from being separated by shearing, and the resistance to shearing is enhanced. The tubular fabric has an elongation in the radial direction.

In order to produce the reinforcing tool 1d, first, a member formed into a shape as shown in FIG. 7B is produced. Thereafter, the main body 2d is softened by heating, as shown in (a) of FIG. 7, is deformed so as to substantially occupied area of the cross section 3d ₁ decreases. Alternatively, a tubular woven fabric is produced using a weft having an expandable elongation in a shape as shown in FIG. 7B, and a member molded using the substantially tubular woven fabric is produced. The restraining portion 25 (FIG. 8) and the seal 31 (FIG. 8) are desirably installed after the production of the tubular fabric.

Furthermore, it is also possible to produce a tubular woven fabric having the features described in [0061]. In that case, the occupation area can be further increased than the reinforcing tool 1d by heating and pressing.

FIG. 8 is a cross-sectional view of the natural ground 9 reinforced with the reinforcing tool 1d. In 3rd Embodiment, as shown in FIG. 8, the natural ground 9 ahead of the face 13 of the tunnel 11 under excavation is reinforced using the reinforcement tool 1d.

In 3rd Embodiment, after drilling the hole 15 in the natural ground 9 by the existing construction method toward the front from the face 13, the reinforcing tool 1d is inserted into the hole 15. The reinforcing tool 1d is manually inserted so that the mouth 29 is located near the entrance of the hole 15. Then, a seal 31 is attached to the mouth 29 of the reinforcing tool 1d. Further, the restraining portion 25 is installed on the side portion of the main body 2d while avoiding the hole 21.

Next, a pressure socket 37 (not shown) is attached to the bag body 33 (not shown) disposed in the interior 7d of the reinforcing tool 1d, and the reinforcing tool 1d is heated and pressurized from the inside of the bag body 33 to expand. Let When heated and pressurized, the main body 2d is restrained from expanding by the restraining portion 25, and the surface is uneven. The expanded reinforcing tool 1 d has a substantially occupied area in the cross section substantially equal to the cross-sectional area of the hole 15. The seal 31 is pressed against the wall surface of the hole 15 as the reinforcing tool 1d expands.

However, regarding the seal 31 between the reinforcing tool 1c and the natural ground 9 at the mouth 29, it is not necessary to use an elastic member, and a seal with urethane may be used as in the related art. In the third embodiment, it is not necessary for the reinforcing material 1d to follow the unevenness of the wall surface of the hole 15.

  After the reinforcing tool 1d is expanded to a predetermined shape, it is cooled and cured while maintaining the pressure and shape of the interior 7d, and the bag 33 (not shown) in the reinforcing tool 1d is removed. Then, an injection tube and a packer (not shown) are installed on the mouth 29 side of the inside 7d of the reinforcing tool 1d, and the injection material 19 is injected. The seal 31 prevents the injection material 19 from leaking into the tunnel 11. The injection material 19 is filled into the hole 15 through the hole 21.

  As described above, in the third embodiment, the reinforcing tool 1d is inserted into the hole 15 with a small cross-sectional area as shown in FIG. A hole longer than various conventional reinforcing materials can be inserted into the hole. Further, the reinforcing tool 1d using the thermoplastic resin can be easily cut when the tunnel 11 is further excavated from the state shown in FIG.

  Since the thermoplastic resin that is the base material of the reinforcing tool 1d can be expanded or deformed with a relatively small force in a state of being softened by heating, a machine that applies high pressure is not required. Therefore, the reinforcing tool 1d can be safely expanded as compared with the conventional method of expanding a metal pipe using high pressure.

In the third embodiment, by injecting the injection material 19 into the hole 15, circumferential friction due to adhesion between the unevenness of the ground 9 and the injection material 19 can be expected. In addition, since the unevenness is formed on the surface of the reinforcing tool 1d after heating and pressurizing, a larger circumference is obtained as compared with the case where the reinforcing tool 1c having a flat surface is reinforced (second embodiment). Surface friction can be exhibited.

  Next, a fourth embodiment will be described. In the fourth embodiment, the configuration is almost the same as that of the reinforcing tool 1d shown in FIG. 7, but the reinforcing tool 1e having no hole 21 and seal 31 is used.

FIG. 9 is a cross-sectional view of the natural ground 9 reinforced with the reinforcing tool 1e. In 4th Embodiment, as shown in FIG. 9, the natural ground 9 ahead of the face 13 of the tunnel 11 under excavation is reinforced using the reinforcement tool 1e.

In the fourth embodiment, the hole 15 is drilled in the natural ground 9 by the existing method from the face 13 toward the front, and then the reinforcing tool 1e is inserted into the hole 15. The reinforcing tool 1e is manually inserted so that the mouth 29 is located near the entrance of the hole 15. And the restraint part 25 is installed in the side part of the main body 2e of the reinforcement tool 1e, avoiding the hole 21. FIG.

Then, a pressurizing socket 37 (not shown) is attached to the bag 33 (not shown) disposed in the interior 7d of the reinforcing tool 1e, and the reinforcing tool 1e is heated and pressurized from the inside of the bag 33 to expand. . When heated and pressurized, the main body 2e is restrained from being expanded by the restraining portion 25, and the surface is uneven. The expanded reinforcing tool 1e pushes and spreads the natural ground 9 in the non-restraining portion, and the restraining portion 25 is generally equal to or smaller than the drilling diameter of the hole 15 depending on the flexibility of the restraining portion 25. .

  In the fourth embodiment, the reinforcing member 1e is caused to follow the unevenness of the wall surface of the hole 15, and in some cases, the hole 15 is expanded so as to be expanded at a portion not restrained by the restraining portion 25. After the reinforcing tool 1e is expanded to a predetermined shape, it is cooled and cured while maintaining the pressure and shape of the inner part 7e, and the bag 33 (not shown) in the reinforcing tool 1e is removed.

As described above, in the fourth embodiment, since the reinforcing tool 1e is inserted into the hole 15 in a state in which the area occupied by the cross section is small, a rough hole or a bent hole can be used instead of various conventional reinforcing materials. Can also insert long ones. Further, the reinforcing tool 1e using a thermoplastic resin can be easily cut when the tunnel 11 is further excavated from the state shown in FIG.

In the fourth embodiment, by deforming the reinforcing tool 1e so as to follow the unevenness of the wall surface of the hole 15, the reinforcing tool 1e bites into the fine unevenness of the natural ground 9, making it difficult to slip, and the axial load is quickly increased. Is transmitted to natural ground 9. Moreover, the process which inject | pours an injection material between the reinforcing tool 1e and the natural ground 9 can be skipped by sticking the reinforcing material 1e to the natural ground 9. Furthermore, since unevenness is formed on the surface of the reinforcing tool 1e after heating, compared with the case where the reinforcing tool 1a and the reinforcing tool 1b having flat surfaces are used (first embodiment), Large circumferential friction can be exerted on the boundary. Since the reinforcing tool 1e can be deformed into a shape different from the shape formed first, the reinforcing tool 1e can be tightly and reliably brought into close contact with the natural ground 9.

  The thermoplastic resin, which is the base material of the reinforcing tool 1e, can be expanded or deformed with a relatively small force when softened by heating, and therefore does not require a machine that applies high pressure. Therefore, the reinforcing tool 1e can be safely expanded as compared with the conventional method of expanding a metal pipe using high pressure.

  In the first to fourth embodiments, the reinforcing tool 1 having a C-shaped or substantially circular cross section before heating and a substantially circular cross section after heating is used. However, the reinforcing tool before and after heating is used. The shape of the cross section is not limited to these. There may be an opening in a part of the cross section, or the cross section may be an ellipse or the like. The reinforcing tool may be rod-shaped instead of tubular. In the reinforcing tool 1 according to the third and fourth embodiments, the restraining portion 25 in the transverse direction is arranged at a predetermined interval in the axial direction. However, the restraining portion 25 may be provided in at least one place of the main body. .

In the first to fourth embodiments, it is also possible to obtain a reinforcing tool that exhibits expandability only in the intended direction by devising the material and weaving method of the continuous fibers.

Furthermore, in the first to fourth embodiments, the bag body 33 is disposed inside the reinforcing tool 1 with both end surfaces open, and the reinforcing tool 1 is heated and pressurized from the inside of the bag body 33 to be expanded. However, the method of expanding the reinforcing tool is not limited to this.

FIG. 10 shows a cross-sectional view of the natural ground 9 reinforced with the reinforcing tool 1f. FIG. 10A is a diagram showing a process of drilling the hole 15 in the natural ground 9 and inserting the reinforcing tool 1f, and FIG. 10B is a diagram illustrating the expanding of the reinforcing tool 1f and the injection material 19. It is a figure which shows the process of inject | pouring. As shown in FIG. 10, a reinforcing tool 1f having an end face on the tip end 17 side closed and an end face on the mouth 29 side opened, the mouth 29 of the reinforcing tool 1f is connected to a heating / pressurizing device, and the reinforcing tool 1f is attached. You may expand by direct heating and pressurization.

When the injection material is injected after heating and pressurizing, it is necessary to provide a simple valve (seal) 23 that opens the hole 21 when a certain pressure is reached in the hole 21 provided in the reinforcing tool 1f. By doing so, the valve (seal) 23 can be closed during heating and pressurization to expand the reinforcing tool 1f, and the valve (seal) 23 can be opened during injection to inject the injection material 19. .

  In the first and fourth embodiments, the reinforcing tool 1 that does not have the hole 21 in the side portion is used, but the reinforcement that has the hole 21 in the side portion as used in the second and third embodiments. Tool 1 may be used. In that case, when the expected peripheral friction cannot be obtained after expanding the reinforcing tool 1 in the hole 15, it is injected between the natural ground 9 and the reinforcing tool 1 through the hole 21 on the side of the main body 2. The material 19 can be post-injected.

  In the second and third embodiments, the injection material 19 is filled between the hole 15 and the reinforcing tool 1, but if necessary, the injection material 19 is placed inside or around the reinforcing material 1. It may be filled.

In the first to fourth embodiments, when double pipe drilling is performed by a conventional basic drilling method without using a construction method that is disadvantageous in terms of cost and process of double pipe drilling. However, the hole drilling method is not limited to this. In general, as called a self-drilling bolt, there is a case in which the reinforcing tool 1 is used instead of a rod and a drilling tool is provided at the tip 17 and the hole 15 is drilled by the reinforcing tool 1. In some cases, the reinforcing tool 1 is manually inserted into the casing tube after drilling, and then the casing tube is pulled out. In addition, a double pipe drilling hole may be employed, and the reinforcing tool 1 may be used as a casing pipe for drilling. At this time, the outer peripheral surface of the casing tube may be provided with a groove for expecting frictional force to the extent that there is no obstacle to the drilling hole, but if the reinforcing tool 1d or the reinforcing tool 1e is used, a hole with a flat wall surface is formed. The conflicting problems can be solved by smoothly drilling holes and making the surface of the reinforcing tool uneven by exerting a frictional force in the subsequent process.

  As mentioned above, although preferred embodiment of the reinforcing tool concerning this invention and the natural ground reinforcement construction method was described referring an accompanying drawing, this invention is not limited to this example. It is obvious for those skilled in the art that various modifications or modifications can be conceived within the scope of the technical idea described in the claims, and these are naturally within the technical scope of the present invention. It is understood that it belongs.

Perspective view of the reinforcing tool 1 Sectional view of ground 9 reinforced with reinforcing tool 1 A sectional view of the reinforcing tool 1 in the axial direction The figure which shows each process at the time of reinforcing the natural ground 9 using the reinforcement tool 1 Perspective view of the reinforcing tool 1c The figure which shows each process at the time of reinforcing the natural ground 9 using the reinforcement tool 1c. Perspective view of the reinforcing tool 1d Sectional drawing of the natural ground 9 reinforced with the reinforcing tool 1d Sectional drawing of the natural ground 9 reinforced with the reinforcing tool 1e Sectional drawing of the natural ground 9 reinforced with the reinforcing tool 1f

Explanation of symbols

1,1a, 1b, 1c, 1d, 1e, 1f ......... brace 2,2a, 2b, 2c, 2d, 2e ......... body _{3,3a 1, 3a 2, 3b 1} , 3b 2, 3c 1, 3c ₂ , 3d ₁ , 3d ₂ ......... cross-section 7, 7a, 7b, 7c, 7d, 7e .... Inside 9 ... ... natural ground 15 ... ... hole 17 ... ... tip 19 ... ... injection material 21 ……… Hole 23 ……… Valve (seal)
25 ......... Restraining part 29 ......... Mouth 31 ......... Seal 33 ......... Bag body

Claims (13)

It has a main body formed of a thermoplastic resin as a base material and reinforced in the axial direction with continuous fibers that are tubular woven fabrics, and the main body expands when heated and pressurized to increase the occupied area of the cross section A reinforcing tool characterized by that.   The reinforcing tool according to claim 1, wherein the tubular fabric has an elongation in a radial direction.   The reinforcing tool according to claim 1, wherein a constraining portion is provided on a part of the main body before heating, and the main body is uneven when heated and pressurized.   The reinforcing tool according to claim 1, wherein a hole is formed in a side portion of the main body.   The reinforcing tool according to claim 1, wherein a drilling tool is provided at the tip.   The said main body does not have a joint part, The reinforcement tool of Claim 1 characterized by the above-mentioned.   The reinforcing tool according to claim 4, wherein the hole is closed until the inside of the main body reaches a predetermined pressure, and is opened when the pressure exceeds the predetermined pressure.   A natural ground reinforcement construction method, wherein the reinforcing tool according to claim 1 is inserted into a hole formed in a natural ground, and then the main body is heated and pressurized to expand to expand an occupied area of a cross section. (A) inserting the reinforcing tool according to claim 4 into a hole formed in the natural ground;
Heating and expanding the body to increase the cross-sectional area occupied (b);
Injecting an injection material from the inside of the main body, and injecting the injection material into the hole formed in the natural ground through the hole provided in the side portion of the main body;
A natural ground reinforcement method characterized by comprising:   10. The natural ground reinforcement method according to claim 9, wherein in the step (c), the injection material is injected into a natural ground around the hole. In the step (a), a bag is installed in the reinforcing tool,
The ground reinforcement method according to claim 9, wherein in the step (b), the main body is heated and pressurized from within the bag body. An elastic member is attached to the mouth side outer periphery of the reinforcing tool,
10. The natural ground reinforcement method according to claim 9, wherein, in the step (b), the elastic member is pressed against the natural ground as the main body expands.   10. The natural ground reinforcement method according to claim 9, wherein in the step (b), the hole is closed until the inside of the main body reaches a predetermined pressure, and is opened when the pressure exceeds the predetermined pressure.

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