Embedding method

Abstract

To provide an embedding method that can simplify equipment and suppress an increase in the number of work steps.SOLUTION: An embedding method includes: a first step S1 of forming an embedding hole in a target location; a second step S2 of placing a cylindrical embedded member and a tension member that is placed inside the embedded member and connected to a longitudinal end of the embedded member, into the embedding hole formed in the target location in the first step S1; a third step S3 of operating the tension member placed in the embedding hole in the second step S2 in a direction going out of the embedding hole to apply a compressive load to the embedded member and cause a part of the embedded member to protrude radially outward; and a fourth step S4 of injecting a hardening material into the embedded member and hardening the hardening material to fix the embedded member to the target location.SELECTED DRAWING: Figure 10

Description

[Technical field]

[0001] The present disclosure relates to an embedding method for embedding an object in a target location. [Background technology]

[0002] An example of an embedding method used to embed objects in a target location is described in Patent Document 1. Patent Document 1 describes ground reinforcement methods such as a ground anchor method, a slope reinforcement method, an underground pile method, a bridge pier reinforcement method, a tunnel face reinforcement method, a pipe roof method, and a chemical injection method.

[0003] The ground reinforcement method described in Patent Document 1 involves rotating a drilling rod with a drilling bit at the tip using a drilling machine to drill holes in the ground (target location). The ground reinforcement method described in Patent Document 1 involves inserting a hole wall retaining casing pipe (rod-shaped buried object) made of a porous pipe with an opening ratio of 20% or more into the hole, and when a hole of a specified depth is formed, the drilling rod is pulled out and recovered from the hole, leaving the casing pipe in the hole. Then, a consolidation material is injected into the hole, causing it to permeate and solidify inside the casing pipe and the surrounding ground. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2002-167746 A Summary of the Invention [Problem to be solved by the invention]

[0005] The present inventors have recognized that the embedding method described in Patent Document 1 has a problem in that the drilling machine is large, making the work cumbersome and complicated.

[0006] An object of the present disclosure is to provide an embedding method that can simplify equipment and suppress an increase in labor hours. [Means for solving the problem]

[0007] The present disclosure relates to an embedding method that includes a first step of forming an embedding hole in a target location by reciprocatingly operating a drilling machine; a second step, which follows the first step, of placing a cylindrical embedding member in the embedding hole and a tension member that is disposed inside the embedding member and connected to a longitudinal end of the embedding member; a third step, which follows the second step, of operating the tension member disposed in the embedding hole in a direction that pulls it out of the embedding hole, thereby applying a compressive load to the embedding member and causing a portion of the embedding member to protrude radially outward; and a fourth step, which follows the third step, of injecting a hardening material into the embedding member and hardening the hardening material to fix the embedded member to the target location. Effect of the Invention

[0008] According to the embedding method of the present disclosure, it is possible to simplify the equipment and suppress an increase in labor hours. [Brief description of the drawings]

[0009] [Figure 1] 1A and 1B are cross-sectional views showing a first step performed in a first specific example of the embedding method. [Diagram 2] 1(A) and 1(B) are cross-sectional views showing the configuration of a steel pipe and a tensile member used in the embedding method. [Diagram 3] 13(A) and 13(B) are cross-sectional views showing a second step performed in the first specific example of the embedding method. [Figure 4] 11 is a cross-sectional view showing a third step performed in the first specific example of the embedding method. FIG. [Diagram 5] FIG. 1A is a cross-sectional view showing a fourth step performed in the first specific example of the embedding method, and FIG. 1B is a cross-sectional view showing a fifth step performed in the first specific example of the embedding method. [Figure 6] 13(A) and 13(B) are cross-sectional views showing an eleventh step performed in a second specific example of the embedding method. [Figure 7] 13(A) and 13(B) are cross-sectional views showing a twelfth step performed in a second specific example of the embedding method. [Figure 8] FIG. 13 is a cross-sectional view showing the 13th step performed in the second specific example of the embedding method. [Figure 9] FIG. 13 is a cross-sectional view showing the 14th step performed in the second specific example of the embedding method. [Figure 10] 1 is a flowchart comprehensively illustrating a first specific example and a second specific example of an embedding method. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] (overview) The embedding method of the present disclosure is carried out to embed an object in a target location. The target location is soil, natural ground, ground, embankment, earth and sand, clayey soil, sandy soil, silt, and backfill soil. The "N value" indicating the strength of the ground, which is an example of the target location, is approximately 5 to 15. Gravel and rocks are excluded from the target location. An embodiment of the embedding method is described based on the drawings. In all the drawings for explaining the embedding method, the same configurations and elements are generally assigned the same symbols.

[0011] (First concrete example) The first specific example of the embedding method is carried out for the purpose of stabilizing a slope provided on the surface of the natural ground and protecting a structure. The stabilization of the slope includes preventing the natural ground from collapsing and preventing the natural ground from falling down. The first specific example of the embedding method embeds anchors as buried objects into a target location in order to fix a protective layer to the target location. A worker sequentially carries out the first step S1 to the fifth step S5 shown in the flow chart of FIG. 10.

[0012] <1st process> The first step S1 includes a step of drilling a hole in the natural ground. FIG. 1(A) shows a self-propelled underground drilling machine 10 used by an operator in the first step. The underground drilling machine 10 is, for example, a Grundmat. The underground drilling machine 10 is connected to a compressor 12 via an air hose 11. The underground drilling machine 10 has a piston operably provided inside and a head 13 provided at the tip. The piston is driven by compressed air supplied from the compressor to strike the head 13.

[0013] The surface of the natural ground 14 shown in FIG. 1(A), that is, the slope 14B, is inclined with respect to the vertical line A1. The vertical line A1 is an imaginary line showing the direction of gravity. A protective layer 15 is provided to cover the slope 14B. The protective layer 15 includes those applied by the mortar spraying method, the vegetation base material spraying method, the spraying frame method, etc. The mortar spraying method is a method of spraying mortar concrete onto the target location. The vegetation base material spraying method is a method of mixing seeds, fertilizer, base material, bonding material, etc., and spraying it onto the target location. The spraying frame method is a method of assembling a freely deformable wire mesh formwork and reinforcing bars on the slope, and spraying mortar or concrete to create the structure.

[0014] The protective layer 15 is applied with a substantially constant thickness. The operator strikes and scrapes the protective layer 15 and the natural ground 14 with the head 13 of the underground drilling machine 10, and advances the underground drilling machine 10 along the center line B1. Thus, as shown in FIG. 1(B), the insertion hole 15A of the protective layer 15 and the embedding hole 14A of the natural ground 14 are formed. The center lines B1 of the insertion hole 15A of the protective layer 15 and the embedding hole 14A of the natural ground 14 are inclined with respect to the vertical line A1 and the horizontal imaginary line A2. In addition, in the height direction along the vertical line A1, the bottom of the embedding hole 14A is located below the insertion hole 15A. After the embedding hole 14A and the insertion hole 15A are formed, the operator retreats the underground drilling machine 10 along the center line B1. That is, the underground drilling machine 10 is reciprocated along the center line B1. The worker pulls out the underground drilling machine 10 from the embedding hole 14A and the insertion hole 15A, and ends the first step S1. Following the first step S1, the worker performs the second step S2.

[0015] <Second process> The second step S2 includes a step of placing the steel pipe 16 shown in Figs. 2(A) and (B) in the embedding hole 14A of the natural ground 14 and the insertion hole 15A of the protective layer 15. The steel pipe 16 is an anchor to be embedded in the natural ground 14, and is made of metal, for example, iron or aluminum. The steel pipe 16 is a cylindrical member centered on the center line B2. The steel pipe 16 has a length L2 in the direction along the center line B2 and an inner diameter φ1. The steel pipe 16 is provided with a male thread 17 and an expandable portion 18 at different positions in the direction along the center line B2. The male thread 17 is provided on the outer circumferential surface of the first end of the steel pipe 16 in the direction along the center line B2. The expandable portion 18 is provided over a predetermined length L1 from the second end of the steel pipe 16 in the direction along the center line B2. The length L1 is less than the length L2. The diameter-expandable portion 18 is configured to deform so as to protrude radially outward when it receives a compressive load in a direction along the center line B2. In other words, the diameter-expandable portion 18 is configured to be able to expand its diameter. The radial direction is the radial direction of the steel pipe 16, that is, the radial direction of a virtual circle centered on the center line B2.

[0016] The expandable portion 18 has a plurality of constituent pieces 19 and slits 20 provided between the plurality of constituent pieces 19. The slits 20 extend in a direction along the center line B2, and are formed by breaking the expandable portion 18 in a radial direction. The plurality of constituent pieces 19 and the plurality of slits 20 are alternately arranged in the circumferential direction of the expandable portion 18. The plurality of constituent pieces 19 each extend in a direction along the center line B2. As shown in FIG. 2(B), the plurality of constituent pieces 19 each have a slit 47 provided at a midpoint in the direction along the center line B2. Therefore, when the expandable portion 18 receives a compressive load, it deforms so as to protrude outward in the radial direction of the steel pipe 16.

[0017] Furthermore, a nut 21 is fixed to a second end in the longitudinal direction of the steel pipe 16. The nut 21 is made of metal, for example, steel or aluminum. The nut 21 has an internally threaded hole 22. The internally threaded hole 22 is disposed about a center line B2. The nut 21 has a thickness L4.

[0018] Furthermore, a tension member 23 is provided. The tension member 23 is an element for applying a compressive load to the steel pipe 16 in a direction along the center line B2. The tension member 23 is, for example, a rod member, and the diameter φ2 of the tension member 23 is less than the inner diameter Φ1 of the steel pipe 16. The tension member 23 has a length L3 in the direction along the center line B2. A male thread is provided on the outer circumferential surface of the tension member 23. The male thread is provided over the entire area of ​​the tension member 23 in the direction along the center line B2.

[0019] 2(A) and (B) is provided. The positioning plate 24 is an element that positions the tension member 23 relative to the nut 21. The diameter φ4 of the positioning plate 24 exceeds the diameter φ3 of the steel pipe 16. The positioning plate 24 has an insertion hole 24A, and the inner diameter of the insertion hole 24A exceeds the diameter φ2 of the tension member 23. The positioning plate 24 has a thickness L5. The length L2 exceeds the length L1. In the direction of the center line B2, the length L3 exceeds the total length L6 which is the sum of the length L2 and the thicknesses L4 and L5.

[0020] In the second step S2, before placing the steel pipe 16 across the embedding hole 14A in the natural ground 14 and the insertion hole 15A in the protective layer 15, the worker brings the positioning plate 24 into contact with the first end of the steel pipe 16, and places the positioning plate 24 and the steel pipe 16 coaxially around the center line B2. The worker then inserts the tension member 23 into the insertion hole 24A, and moves the tension member 23 in a direction along the center line B2 to advance the tension member 23 into the interior 16A of the steel pipe 16. The worker inserts the tip of the tension member 23 into the female thread hole 22 of the nut 21, and then rotates the tension member 23 around the center to screw the tension member 23 and the nut 21 together. Furthermore, the worker moves the connected steel pipe 16 and pulling member 23 in a direction along the center line B2, and inserts the steel pipe 16 and the pulling member 23 into the insertion hole 15A in the protective layer 15 and the embedding hole 14A in the natural ground 14. The worker then stops the steel pipe 16 and the pulling member 23 as shown in Fig. 3(A), completing the second step. In this embodiment, when the steel pipe 16 and the pulling member 23 are stopped, the center line B1 and the center line B2 are arranged coaxially.

[0021] With the nut 21 positioned at the tip in the insertion direction, the worker inserts the steel pipe 16 and the pulling member 23 into the insertion hole 15A and the embedding hole 14A. When the worker stops the steel pipe 16 and the pulling member 23, the male thread 17 is positioned outside C1 of the natural ground 14 and the protective layer 15. Following the second step S2, the worker performs the third step S3.

[0022] <3rd process> The third step S3 includes a step of expanding the diameter of the diameter-expandable portion 18 of the steel pipe 16. In the third step S3, a hydraulic jack 25 shown in FIG. 3(B) is used. The hydraulic jack 25 has a hydraulic cylinder 26, a tension bar 27, a coupler 28, a ram chair 29, a plate 30, etc. In addition, in the third step, a hydraulic pump 31, an auxiliary plate 32, etc. are used. The hydraulic pump 31 has a pressure gauge 33, and the hydraulic pump 31 is driven by a drive source. The discharge pressure of the hydraulic pump 31 is transmitted to the hydraulic jack 25 via a hydraulic hose 34.

[0023] The hydraulic cylinder 26 of the hydraulic jack 25 is actuated in a direction along the center line B2 in response to changes in hydraulic pressure. The tension bar 27 is actuated in a direction along the center line B2 together with the hydraulic cylinder 26. An actuation amount indicator 46 is provided that displays the actuation amount of the hydraulic cylinder 26. An operator can check the actuation amount of the hydraulic cylinder 26 by visually checking the actuation amount indicator 46. The actuation amount of the hydraulic cylinder 26 corresponds to the movement amount by which the pulling member 23 is pulled along the center line B1 of the steel pipe 16.

[0024] The coupler 28 is a device that connects the tension bar 27 and the pulling member 23. The ram chair 29 is a frame that protrudes from the hydraulic jack 25. The ram chair 29 is made of metal. The auxiliary plate 32 is made of metal and is annular. The diameter of the plate 30 exceeds the inner diameter of the insertion hole 15A of the protective layer 15. The plate 30 is provided at the tip of the ram chair 29. The auxiliary plate 32 is made of metal and is annular. The auxiliary plate 32 has a female threaded hole.

[0025] The worker inserts the male thread 17 of the steel pipe 16 into the female threaded hole of the auxiliary plate 32, and rotates the auxiliary plate 32 to tighten and fix it. The worker moves the hydraulic jack 25 in a direction along the center line B2, bringing it closer to the steel pipe 16. The worker inserts the tip of the steel pipe 16 into the plate 30, and after the plate 30 comes into contact with the auxiliary plate 32, the worker stops the hydraulic jack 25. The worker connects the coupler 28 and the pulling member 23.

[0026] With the plate 30 in contact with the surface of the protective layer 15, the worker drives the hydraulic pump 31 to increase the hydraulic pressure acting on the hydraulic jack 25. Then, the hydraulic cylinder 26 and the tension bar 27 operate a predetermined amount along the center line B2 in a direction away from the protective layer 15, and then stop. The reaction force generated in the process of operating the hydraulic cylinder 26 and the tension bar 27 is transmitted to the natural ground 14 via the ram chair 29, the plate 30, and the protective layer 15. Therefore, the pulling member 23 operates in a direction to be pulled out of the embedding hole 14A of the natural ground 14, and then stops.

[0027] When the tension member 23 is operated, the nut 21 is moved along the center line B2 in a direction approaching the protective layer 15, and then stopped. As a result, the diameter-expandable portion 18 is subjected to a compressive load in a direction along the center line B2. Then, the multiple component pieces 19 are deformed outward in the radial direction of the steel pipe 16, and a part of the diameter-expandable portion 18 becomes a diameter φ5 as shown in FIG. 3(B). The diameter φ5 exceeds the diameter φ3.

[0028] The worker can check the pulling pressure of the hydraulic jack 25 by visually checking the pressure gauge 33. The worker can also check the operation amount of the hydraulic cylinder 26 by visually checking the operation amount indicator 46. The diameter φ5 is determined based on the operation amount of the hydraulic cylinder 26, the pulling pressure of the hydraulic jack 25, the length L8 from the slit 47 of the expandable portion 18 to the end 49, and the like. The worker has acquired correlation information that defines the relationship between the diameter φ5 and the operation amount of the hydraulic cylinder 26, the pulling pressure of the hydraulic jack 25, the length L8 from the slit 47 of the expandable portion 18 to the end 49, and the like. The correlation information is created based on experiments and simulations. The worker adjusts the operation amount of the hydraulic cylinder 26 and the pulling pressure of the hydraulic jack 25 based on the correlation information so as to obtain the target diameter φ5.

[0029] After the expandable portion 18 is protruded outward, the worker stops the hydraulic pump 31 and removes the coupler 28 from the pulling member 23. The worker further moves the hydraulic jack 25 from the vicinity of the natural ground 14 and removes the auxiliary plate 32 from the male screw 17, as shown in Figure 4, to complete the third step S3. Following the third step S3, the worker performs the fourth step S4.

[0030] <4th process> The fourth step S4 includes a step of injecting cement milk into the hole A in the natural ground 14 and hardening the cement milk. In the fourth step S4, a mixing tank 35, a mixer 36, and a grout pump (mortar pump) 37 shown in FIG. 4 are used. The suction port of the grout pump 37 is connected to the mixing tank 35, and the discharge port of the grout pump 37 is connected to a first end of a grout hose 38. The second end of the grout hose 38 is inserted into the interior 16A of the steel pipe 16.

[0031] In the fourth step S4, the worker supplies cement 39 and water into the mixing tank 35. Next, the worker drives the agitator 36 to agitate the cement 39 and water to generate cement milk (mortar) 40. Furthermore, the worker drives the grout pump 37 to pump the cement milk 40 in the mixing tank 35 to the interior 16A of the steel pipe 16 via the grout hose 38. The cement milk 40 fills the interior 16A of the steel pipe 16 and the internal space of the diameter-expandable portion 18. A portion of the cement milk 40 passes through the slit 20 of the diameter-expandable portion 18 and fills the space between the steel pipe 16 and the inner surface of the embedding hole 14A without leaving any gaps.

[0032] After filling the interior 16A of the steel pipe 16 with the cement milk 40 and filling the embedding hole 14A, the worker stops the grout pump 37 and removes the grout hose 38 from the interior 16A of the steel pipe 16. The worker confirms that the cement milk 40 filled in the interior 16A of the steel pipe 16 and the embedding hole 14A has hardened, and ends the fourth step S4. Following the fourth step S4, the worker performs a fifth step S5.

[0033] <5th process> The fifth step S5 includes a step of fixing the steel pipe 16 to the natural ground 14. In the fifth step S5, the hydraulic jack 25, the hydraulic pump 31, and the like shown in FIG. 5(A) are used as in the third step S3. In the fifth step, the pressure plate 41, the fixing nut 42, the protective nuts 43 and 44, and the like shown in FIG. 5(B) are further used. The pressure plate 41 is annular and is made of, for example, steel, synthetic resin, or concrete. The diameter of the pressure plate 41 exceeds the diameter φ3 of the steel pipe 16. The worker attaches the pressure plate 41 to a portion of the steel pipe 16 exposed to the outside C1 as shown in FIG. 5(A). The worker also attaches the fixing nut 42 and the protective nut 43 to the male thread 17 of the steel pipe 16.

[0034] Furthermore, the worker brings the ram chair 29 of the hydraulic jack 25 into contact with the pressure plate 41 and connects the coupler 28 to the pulling member 23. Then, the worker drives the hydraulic pump 31 to increase the hydraulic pressure of the hydraulic jack 25 and pulls the pulling member 23 toward the outside C1. The reaction force generated in the process of pulling the pulling member 23 is transmitted to the ground 14 via the pressure plate 41 and the protective layer 15. The worker tightens the fixing nut 42 and the protective nut 43 while pulling the pulling member 23 with the hydraulic jack 25. The pressure of the hydraulic jack 25 used by the worker in the fifth step is adjusted according to the design strength of the pulling member 23, the amount of penetration of the expandable portion 18 into the ground 14, the amount of sinking of the plate 30, and the like.

[0035] After tightening the fixing nut 42 and the protective nut 43, the worker stops the hydraulic pump 31 and removes the coupler 28 from the pulling member 23. As shown in FIG. 5(B), the worker moves the hydraulic jack 25 from the vicinity of the protective layer 15, and then attaches and tightens the protective nut 44 to the male thread 17 of the pulling member 23. The worker further attaches the head cap 45 to the pressure plate 41 to cover the protective nuts 43, 44 and the fixing nut 42, and the fifth step is completed. The head cap 45 is filled with anti-rust oil (grease). When the fifth step is performed, the protective layer 15 is sandwiched between the natural ground 14 and the pressure plate 41, and the protective layer 15 is fixed to the slope 14B.

[0036] (Effects of the first concrete example of the embedding method) A self-propelled underground drilling machine 10 is used to compact the soil of the natural ground 14 and to advance while crushing gravel and the like, forming the burial hole 14A. As the underground drilling machine 10 advances, the surrounding soil and sand are compacted, and the walls (inner surface) of the burial hole 14A are strongly constructed. Furthermore, since the underground drilling machine 10 is used for compaction penetration, there is no need to remove soil, and no need to treat the surplus soil. Furthermore, water is not supplied in the process of forming the burial hole 14A. Therefore, no drainage process or drainage treatment facility is required.

[0037] In addition, there is no need for scaffolding, cranes, plant yards, etc. used by workers. The underground tunneling machine 10 is lightweight, so construction can be performed by human power. Since a self-propelled underground tunneling machine 10 is used, even if the acute angle between the slope 14B and the virtual line A2 shown in FIG. 1(B) is 70 degrees or more, a strong wall of the embedment hole 14A is constructed by consolidation penetration. Therefore, there is no risk of the wall of the embedment hole 14A collapsing. Therefore, the process of inserting the steel pipe 16 into the embedment hole 14A can be performed smoothly.

[0038] In the embedding method of this embodiment, the pulling member 23 pulls the nut 21 to apply a compressive load to the steel pipe 16, thereby expanding the diameter of the expandable portion 18. The diameter φ5 of the expanded protruding portion of the expandable portion 18 exceeds the diameter φ3 of the steel pipe 16 other than the expandable portion 18. The pulling member 23 is inserted into the inside of the steel pipe 16 and the inside of the expandable portion 18, and the cement milk 40 is filled into the inside of the steel pipe 16, the inside of the expandable portion 18, and the embedding hole 14A, and the cement milk 40 is hardened (solidified).

[0039] Therefore, when an external force is applied in a direction along the center line B2 to pull the steel pipe 16 out of the embedment hole 14A, the pressure-receiving area is expanded by the expandable portion 18, and the resistance to the force that tries to pull the steel pipe 16 out of the natural ground 14 increases. The resistance increases relatively as the diameter φ5 of the expandable portion 18 becomes larger. Therefore, the steel pipe 16 as an anchor maintains the function of firmly fixing the protective layer 15 to the slope 14B of the natural ground 14.

[0040] In the first specific example, the tension member 23 is disposed throughout the interior 16A of the steel pipe 16 and the interior of the expandable portion 18, and the tension member 23 is fixed to the nut 21. The interior 16A of the steel pipe 16, the interior of the expandable portion 18, and the interior of the embedding hole 14A are filled with cement milk 40, and the cement milk 40 is hardened. Therefore, even if an external force is applied in a direction along the center line B2 to pull the steel pipe 16 out of the embedding hole 14A, and an external force is generated that tries to reduce the diameter of the expandable portion 18, the tension member 23 prevents the diameter of the expandable portion 18 from being reduced. In other words, the tension member 23 functions as an element that prevents the diameter of the expandable portion 18 from being reduced. Therefore, the function of the steel pipe 16 as an anchor to fix the protective layer 15 to the slope 14B of the natural ground 14 can be suppressed from being reduced.

[0041] Furthermore, the tension member 23 has both the function of applying a compressive load to the steel pipe 16 to expand the diameter of the diameter expandable portion 18, and the function of preventing the diameter of the diameter expandable portion 18 from decreasing after the cement milk hardens. Therefore, the equipment used in the embedding method can be simplified, and an increase in the number of work steps can be suppressed.

[0042] In this embodiment, the position where the protrusion is formed in the expandable portion 18 can be changed by changing the position where the slit 47 is provided in the expandable portion 18 in the direction along the center line B2. When the length L7 is longer than the length L8, the expandable portion 18 expands into a top shape. When the length L7 and the length L8 are substantially the same, the expandable portion 18 expands into a diamond shape. The diameter of the expandable portion 18 when expanded into a top shape exceeds the diameter of the expandable portion 18 when expanded into a diamond shape. The length L7 is the distance from the slit 47 to the end 48 of the expandable portion 18 that is closer to the nut 21. The length L8 is the distance from the slit 47 to the end 49 opposite the nut 21.

[0043] If the ground 14 is of relatively hard and strong soil quality (loam layer, etc.), it is more suitable for the expandable portion 18 to be expanded into a diamond shape. If the ground 14 is of relatively soft and weak soil quality (fill soil, silt), it is more suitable for the expandable portion 18 to be expanded into a top shape. In this way, by selecting the shape in which the expandable portion 18 is expanded, the resistance to the ground is increased.

[0044] Furthermore, in the height direction along the vertical line A1, the bottom of the embedding hole 14A is located lower than the insertion hole 15A. Therefore, in the process of injecting the cement milk 40 into the inside 16A of the steel pipe 16, the inside of the diameter-expandable portion 18, and the embedding hole 14A, the cement milk 40 does not flow out of the insertion hole 15A to the outside C1 by its own weight before hardening.

[0045] (Second concrete example) The second specific example of the embedding method is an example in which a pile, which plays a role in transmitting the load of a structure from the foundation to the ground (supporting ground), is embedded into the ground 14 shown in FIG. 6(A). A worker performs the eleventh step S11 to the fourteenth step S14 shown in FIG. 10 in order. The second specific example of the embedding method may refer to the figures used in the first specific example of the embedding method. In the figures explaining the second specific example of the embedding method, the same symbols as those in the first specific example of the embedding method are used.

[0046] <Step 11> In the eleventh step S11, as shown in Figs. 6(A) and (B), the worker uses the underground drilling machine 10 to form an embedment hole 14A in the natural ground 14. The underground drilling machine 10 advances (descends) and retreats (rises) in a direction along a vertical line A1. The center line B1 of the embedment hole 14A and the vertical line A1 are coaxially positioned. The embedment hole 14A is opened in the surface 14C of the natural ground 14. Here, it is assumed that the surface 14C is approximately horizontal. After forming the embedment hole 14A, the worker retreats the underground drilling machine 10 and removes it from the embedment hole 14A, thus completing the eleventh step S11. Following the eleventh step S11, the worker performs a twelfth step S12.

[0047] <12th process> The twelfth step S12 includes inserting the steel pipe 16 and the tension member 23 shown in Figs. 2(A) and (B) into the embedding hole 14A of the natural ground 14. In the second specific example of the embedding method, the steel pipe 16 is embedded into the natural ground 14 as a pile. Here, for convenience, an example in which the male thread 17 of the steel pipe 16 is not provided will be described. The worker positions the steel pipe 16 with the nut 21 facing downward relative to the embedding hole 14A, and lowers the steel pipe 16 and the tension member 23 to insert the steel pipe 16 and the tension member 23 into the embedding hole 14A as shown in Fig. 7(A). The upper end of the steel pipe 16 is located outside C1 of the natural ground 14. When the worker inserts the steel pipe 16 and the tension member 23 into the embedding hole 14A, the twelfth step S12 is completed. Following the twelfth step S12, the worker performs the thirteenth step S13.

[0048] <13th process> The thirteenth step S13 includes a step of expanding the diameter of the expandable portion 18 of the steel pipe 16. In the thirteenth step S13, the worker uses the hydraulic jack 25 and the hydraulic pump 31 shown in FIG. 7(B). After connecting the pulling member 23 and the coupler 28, the worker drives the hydraulic pump 31 with the plate 30 in contact with the surface 14C. Then, the pulling member 23 is pulled toward the outside C1, as in the third step. The reaction force generated in the process of operating the hydraulic cylinder 26 and the tension bar 27 is transmitted to the natural ground 14 via the ram chair 29 and the plate 30. Then, when the hydraulic pump 31 is stopped, the pulling member 23 is stopped.

[0049] In the process from when the pulling member 23 moves toward the outside C1 until it stops, a compressive load is applied to the expandable portion 18 in the same principle as in the third step. Therefore, the expandable portion 18 expands outward and increases in diameter to φ5. The worker can adjust the diameter φ5 of the expandable portion 18 in the same manner as in the third step. After the expandable portion 18 is protruded outward, the worker stops the hydraulic pump 31 and removes the coupler 28 from the pulling member 23. The worker moves the hydraulic jack 25 from the vicinity of the natural ground 14. The worker removes the pulling member 23 from the nut 21 and takes out the pulling member 23 from the embedding hole 14A, completing the thirteenth step S13. Following the thirteenth step S13, the worker performs a fourteenth step S14.

[0050] <14th process> The fourteenth step S14 includes a step of injecting cement milk into the hole A in the natural ground 14 and hardening the cement milk. In the fourteenth step S14, a mixing tank 35, a stirrer 36, and a grout pump 37 shown in FIG. 8 are used. The discharge port of the grout pump 37 is connected to a first end of a grout hose 38. The second end of the grout hose 38 is inserted into the interior 16A of the steel pipe 16.

[0051] The fourteenth step S14 performed by the worker is substantially the same as the fourth step S4. The worker drives the grouth pump 37 to pump the cement milk 40 in the mixing tank 35 to the inside 16A of the steel pipe 16 through the grouth hose 38. The cement milk 40 fills the inside 16A of the steel pipe 16 and the internal space of the diameter-expandable portion 18. A part of the cement milk 40 passes through the slit 20 of the diameter-expandable portion 18 and fills the space between the steel pipe 16 and the inner surface of the embedding hole 14A without leaving any gaps.

[0052] The worker then stops the grout pump 37 and removes the grout hose 38 from the inside 16A of the steel pipe 16. The worker confirms that the cement milk 40 filled in the inside 16A of the steel pipe 16 and the embedding hole 14A has hardened, and then places a cap on the steel pipe 16, completing the 14th step S14. In the second specific example, the 5th step is not performed. The second specific example can obtain the same effect as the first specific example.

[0053] In addition, in the thirteenth step S13 of the second specific example, the worker may leave the tension member 23 inside the interior 16A of the steel pipe 16, similar to the third step of the first specific example. Then, in the fourteenth step S14, the worker fills the interior 16A of the steel pipe 16 with the cement milk 40 and hardens the cement milk 40 with the tension member 23 disposed inside the interior 16A of the steel pipe 16, similar to the fourth step.

[0054] (Other explanations) An example of the technical meaning of the matters disclosed in this embodiment is as follows. The underground tunneling machine 10 is an example of a tunneling machine. The natural ground 14 is an example of a target location. The buried hole 14A is an example of a buried hole. The first step S1 and the eleventh step S11 are an example of a first step. The second step S2 and the twelfth step S12 are an example of a second step. The third step S3 and the thirteenth step S13 are an example of a third step. The fourth step S4 and the fourteenth step S14 are an example of a fourth step. The fifth step S5 is an example of a fifth step. The steel pipe 16 is an example of an buried member. The tension member 23 is an example of a tension member.

[0055] The cement milk 40 is an example of a hardening material. The hydraulic jack 25 and the hydraulic pump 31 are an example of a traction device. The hydraulic pressure of the hydraulic jack 25 is an example of the operating force of the traction device. The expandable portion 18 is an example of a "part of the embedded member". The diameter φ5 is an example of a diameter. The fixing nut 42 and the protective nuts 43, 44 are an example of a fixing element. The slope 14B is an example of a surface of the target location. The protective layer 15 is an example of a protective layer. The insertion hole 15A is an example of an insertion hole. The center line B1 is an example of a center line of an embedded hole. The vertical line A1 is an example of a vertical line.

[0056] This embodiment is not limited to those disclosed using the drawings, and various modifications are possible without departing from the gist of the present invention. For example, the length (total length) of the steel pipe and the length (total length) of the tension member are determined according to the depth of the embedded hole to be formed in the target location. Also, multiple steel pipes can be used by extending (connecting) them in the direction along the center line. Furthermore, the traction device may be an air jack or an electric motor type actuator. The operating force of the air jack is air pressure. The operating force of the electric motor type actuator is the rotational force of the electric motor. [Industrial Applicability]

[0057] The embedding method of the present embodiment can be used when forming an embedding hole in a target location and embedding an embedding member in the embedding hole. [Explanation of symbols]

[0058] 10...underground drilling machine, 14...natural ground, 14A...embedding hole, 14B...slope, 15...protective layer, 15A...insertion hole, 16...steel pipe, 18...expandable portion, 23...pulling member, 25...hydraulic jack, 31...hydraulic pump, 40...cement milk, 42...anchoring nut, 43, 44...protective nut, A1...vertical line, B1...center line, φ5...diameter

Claims

1. A first step of forming an embedding hole in a target location by reciprocating a drilling machine; a second step, which is performed following the first step, of disposing a cylindrical embedding member in the embedding hole and a tension member disposed inside the embedding member and connected to an end of the embedding member in a longitudinal direction; a third step, which is carried out following the second step, of applying a compressive load to the embedded member by operating the tension member disposed in the embedded hole in a direction in which the tension member is pulled out of the embedded hole, thereby causing a portion of the embedded member to protrude outward in a radial direction; a fourth step, which is carried out following the third step, of injecting a hardening material into the interior of the embedding member and hardening the hardening material to fix the embedding member to the target location; An embedding method.

2. The embedding method according to claim 1, The third step is to operate the pulling member in a direction to pull out of the embedding hole by an operating force of a traction device, The third step is an embedding method in which the diameter of a portion of the embedded member protruding radially outward is adjusted based on the operating force of the traction device and the operating amount of the pulling member in the direction of coming out of the embedding hole.

3. The embedding method according to claim 1 or 2, The first step includes forming an insertion hole in a protective layer covering a surface of the target location and forming the embedding hole in the target location by reciprocating the piercing machine; The fourth step is an embedding method in which the hardening material is injected into the inside of the embedding member while the tension member is placed in the insertion hole and the embedding hole.

4. The embedding method according to claim 3, The embedding method further comprises a fifth step of pulling the tension member in a direction away from the embedding hole following the fourth step, and attaching a fixing element to the tension member, thereby fixing the protective layer to the surface of the target location.

5. The embedding method according to claim 3, The first step forms the embedment hole in a slope that constitutes a part of the target location, The first step is an embedding method in which a center line of the embedding hole is inclined with respect to a vertical line.

6. The embedding method according to claim 1 or 2, The first step includes arranging the center line of the embedding hole along a vertical line, The fourth step is an embedding method, in which the hardening material is injected into the inside of the embedding member with the tension member removed from the embedding hole.

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