JP3774886B2 - Anchor construction method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an anchor construction method suitable for constructing an anchor on a ground where groundwater moves vigorously such that highly pressurized water flows out.
[0002]
[Prior art]
In conventional anchors, unbonded PC steel wires and other materials are used as a tension material, and an curtain rod is inserted into the anchor hole and fixed under the injection and solidification of the grout material. is there.
[0003]
An example of a conventional anchor construction method will be described with reference to FIGS. 8 is a sectional view showing a conventional example of an anchor, and FIG. 9 is a partially enlarged perspective view of FIG.
An anchor body 7 is formed in the anchor hole 6 excavated in the ground and solidified by injecting a grout material such as cement milk. In the anchor body 7, a plurality (three in this example) of load bearing bodies 2a are formed. 2b and 2c are arranged at different depth positions, and the load bearing members 2a, 2b and 2c are anchors in which tension materials 3 such as independent unbonded PC steel wires are wound in a U-turn. The tendon 1 is provided, and the end of the tension member 3 is tensioned and fixed outside the opening of the anchor hole 6.
[0004]
The anchor hole 6 is drilled by using a drilling machine, the grout material is primarily injected into the anchor hole 6, and the rebound tension material 3 processed with tendon 1 is inserted therein, and then the casing is mounted. The secondary injection of the grout material is performed while being pulled out, and after the grout material is solidified, the plurality of tension materials 3 are tensioned and fixed. A drilling rod of a drilling machine is used as it is for the casing.
[0005]
As shown in FIG. 9, the load bearing bodies 2a, 2b, and 2c are formed with U-shaped grooves 9 that are inserted and folded back (U-turned) by inserting the tension material 3 into the tip. The ends of the bodies 2a, 2b and 2c are inserted into the grooves 9 and bent, and are U-turned, and fixed to the load-resistant bodies 2a, 2b and 2c with the metal band 10.
[0006]
The load-bearing bodies 2a, 2b, and 2c are arranged at equal intervals or unequal intervals in the fixing unit at different depth positions. For this reason, since the tension material 3 turned back from the load resistance body 2a on the deep position side passes through the side portions of the load resistance bodies 2b and 2c on the shallow position side, all of these tension materials 3 are also the load resistance bodies 2b and 2c. It is fixed with a metal band 10. That is, the tension member 3 folded back from the load bearing member 2a is also fixed to the load bearing member 2b, and the tension member 3 folded from the load bearing members 2a and 2b is also fixed to the load bearing member 2c (see FIG. 9). . The length of the fixing portion is determined by the diameter of the drilling hole, the nature of the ground soil, or the like corresponding to the design load.
[0007]
The plurality of tension members 3 arranged as described above are tensioned and fixed outside the opening of the anchor hole 6. In FIG. 8, fixing is performed by fixing tools such as a pedestal 11, a support plate 12, and an anchor head 13. Reference numeral 14 denotes a mountain retaining wall, and 15 denotes an erection material.
[0008]
[Problems to be solved by the invention]
However, in the conventional anchor construction method as described above, if the ground is a ground where the groundwater is flowing so that the highly pressurized water flows out, even if the grout material is injected into the anchor hole 6, The grout material is washed by the pressurized water until it hardens, the grout material is diluted, the anchor cannot be formed, the adhesion between the anchor body 7 and the ground is adversely affected, and the predetermined anchor strength cannot be obtained. There are issues such as.
[0009]
The present invention has been proposed to solve such problems of the prior art, and its purpose is optimal for constructing anchors on ground where groundwater moves vigorously such that highly pressurized water flows out. The provision of anchor construction methods.
[0010]
[Means for Solving the Problems]
In order to solve the above problems, the anchor construction method of the present invention is characterized by the following steps.
(1) A step of drilling an anchor hole to a predetermined depth at a predetermined angle using a drilling pipe having a discarded bit at the tip;
(2) Cover the fixing part of the uncurtain dong in advance with a woven cloth bag, and insert the grouting injection hose and the grouting filling hose into the uncured dong. Inserting step,
(3) A step of tapping a discarded bit at the tip of the casing with the inserted an curtain curtain to remove it from the casing;
(4) a step of pulling out the casing so as not to damage the inserted an curtain curtain;
(5) A step of injecting a grout material into the bag by a grout injecting hose,
(6) Checking the filling state of the grout material with a grout filling confirmation hose, and closing the grout filling confirmation hose when a predetermined filling state is reached,
(7) Further, the grout material is pressurized and injected from the hose for injecting the grout, and the outer peripheral surface of the bag body is press-contacted to the hole wall of the anchor hole to improve the adhesion between the ground and the anchor fixing body. Closing the grout injection hose after pressure injection and solidifying the grout material,
(8) A step of stopping the mouth of the anchor hole with a mouth packer,
(9) A step of tensioning and fixing the tension material of the uncurtain don.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 to 5 are schematic sectional views showing the embodiment of the present invention in the order of construction, FIG. 6 is a partial perspective view showing the embodiment of the present invention, and FIG. 7 is a diagram of a load bearing body used in the anchor construction method of the present invention. It is a perspective view, and the same components as those in the conventional example shown in FIGS.
[0012]
In the anchor construction method of the present invention, a woven cloth bag body 8 is covered in a range corresponding to the fixing portion of the an curtain curtain 1, and a grout injection pipe 16 is inserted into the bag body 8 as a grout injection hose. After sealing the opening 17 and inserting the uncurtain don 1 including the grout injection pipe 16 covered with the bag body 8 into the anchor hole 6, the grout material is pressurized and injected through the grout injection pipe 16. Pressure filling is performed until the outer peripheral surface of the body 8 is pressed and adhered to the hole wall of the anchor hole 6.
[0013]
As shown in FIG. 6, the uncurtain dong 1 has a plurality of load-bearing bodies 2 and 2 arranged on the same axis, and each load-bearing body 2 and 2 is made to turn a tension material 3 such as a PC stranded wire independently. The grout injection pipe 16 is also fixedly disposed on the load-bearing bodies 2 and 2 and is incorporated so as to be a part of the uncurtain don 1, and the fixing portion of the uncurtain don 1 including the grout injection pipe 16 A woven cloth bag body 8 is covered in a range corresponding to the above, and the opening is sealed 17 and inserted into the anchor hole 6, and then the grout material is pressurized and injected through the grout injection pipe 16. Pressure filling is performed until the outer peripheral surface of 8 is in pressure contact with the hole wall of the anchor hole 6.
[0014]
More specifically, referring to FIG. 1 to FIG. 5, first, as shown in FIG. 1, a drilling pipe (this is a single-pipe pipe) 20 having a discarded bit 21 at its tip using an excavator (not shown). Then, the anchor hole 6 is drilled. This is done at a predetermined angle to a predetermined depth. After drilling to a predetermined depth, the drilling is stopped, the excavator is removed from the excavation pipe 20, and the excavation pipe 20 is used as a casing.
[0015]
On the other hand, a woven cloth bag 8 is covered in advance in a range corresponding to the fixing portion of the uncurtain don 1, and a grout injection hose 22 (grouting pipe 16) and a grout filling confirmation hose (hereinafter referred to as return). An uncurtain dong 1 into which a hose) 23 is inserted is prepared, and the uncurtain dong 1 is inserted into the excavation pipe 20 as a casing as shown in FIG. Reference numeral 17 denotes a sealing portion of the opening of the bag body 8.
[0016]
Preferably, as shown in FIG. 6, a plurality of load bearing bodies 2, 2 are arranged on the same axis, and each of the load bearing bodies 2, 2 is configured to turn independent tension members 3, and the grout injection pipe 16 is also configured as described above. The uncurtain dong 1 is fixed and arranged on the load-bearing bodies 2 and 2 and covered with a bag 8 made of woven cloth in a range corresponding to the fixing portion including the grout injection pipe 16 and the opening thereof is sealed. . As shown in FIG. 7, the load-bearing body 2 includes a groove 9 for inserting the tension material 3 to make a U-turn and a groove 19 for inserting the grout injection pipe 16. The tension material 3 is a groove. The grout injection pipe 16 is inserted into the concave groove 19 and piped, and both are fastened and fixed by the metal band 10. The uncurtain dong 1 configured as described above is inserted into the casing 20. In this example, the grouting pipe 16 serves as the grouting hose 22.
[0017]
Next, as shown in FIG. 2, with the uncurtain don 1 inserted into the casing 20, the discard bit 21 at the tip of the casing 20 is tapped and removed (separated) from the casing 20. Here, the reason why the discard bit 21 is removed from the casing 20 is to pull out the casing 20 while leaving the uncurtain dong 1 in the anchor hole 6 in the next step. This is because the presence of the discard bit 21 is an obstacle, and the uncurtain don 1 cannot be pulled out while remaining in the anchor hole 6. The discard bit 21 has a structure that can be removed by tapping with the uncurtain dong 1, and conventionally known means are employed.
[0018]
Next, as shown in FIG. 3, the casing 20 is pulled out so as not to damage the inserted uncurtain dong 1. Then, the uncurtain dong 1 is placed in the anchor hole 6 and the discard bit 21 is left at the bottom of the anchor hole 6.
[0019]
Next, as shown in FIG. 4, a grout material such as cement milk is pressurized and injected into the bag body 8 from the grout injection hose 22 or the grout injection pipe 16. Confirmation of the filling state by pressure injection of the grout material is confirmed by a return hose 23 for grout filling confirmation. When the grout material flowing out from the return hose 23 has the same density as the grout material injected from the grout injection hose 22 or the grout injection pipe 16, it is determined as a predetermined filling state. When the return hose 23 confirms the predetermined filling state, the return hose 23 is closed. At this time, the inside of the bag body 8 is filled with the grout material.
[0020]
Next, when the return hose 23 is closed, the grout material is further pressurized and injected from the grout injection hose 22 or the grout injection pipe 16, and the outer peripheral surface of the bag body 8 is pressed and adhered to the hole wall of the anchor hole 6. The adhesiveness between the ground and the anchor body (anchor fixing body) 7 is improved, and after sufficiently pressurized injection, the grout injection hose 23 or the grout injection pipe 16 is closed to solidify the grout material. The bag body 8 is made of woven fabric. At this time, the grout material oozes out from the outer peripheral surface of the bag body 8 to improve the adhesion with the hole wall (ground) of the anchor hole 6 and integrate it, thereby increasing the proof stress. Because.
[0021]
Next, as shown in FIG. 5, the mouth of the anchor hole 6 is stopped by the mouth packer 24. The mouth packer 24 is set at the mouth of the water blocking wall portion 18 through the uncurtain don 1, and a grout material such as cement milk is injected and filled into the mouth packer 24 from the hose 25, and the filling is stopped after confirming that the flowing water stops. . Further, a grout material is injected into the cavity of the anchor hole 6 inside the mouth packer 24 using the hose 26.
[0022]
Finally, the tension material 3 of the uncurtain don 1 is tensioned and fixed. Conventionally known means are employed as the tension and fixing means.
[0023]
The uncurtain dong 1 is inserted into the anchor hole 6 with the bag body 8 covering the portion corresponding to the fixing portion, and the grout material is injected into the bag body 8 under pressure to construct the anchor. Even if the ground is a ground where the groundwater is intensively flowing out of high pressure water, it is not washed or diluted before the grout material is solidified.
The above embodiment is for explaining the present invention, and is not intended to limit the present invention. Modifications, modifications, etc. are allowed within the technical scope of the present invention.
[0024]
【The invention's effect】
As explained in detail above, the anchor construction method of the present invention covers a woven cloth bag in a range corresponding to the fixing portion of the uncurtain don, and inserts a grout injection hose (grouting pipe) into the bag, After sealing the opening of the bag body and inserting an uncurtain don including a grout injection hose (grouting pipe) covered with the bag body into the anchor hole, the grout from the grout injecting hose (grouting pipe) Since the material is pressurized and filled until the outer peripheral surface of the bag body is in pressure contact with the hole wall of the anchor hole, the ground is a ground where the groundwater moves rapidly so that highly pressurized water flows out. However, the filled grout material is not washed or diluted before solidifying, the anchor cannot be formed, the adhesion between the anchor body and the ground is adversely affected, and the predetermined anchor strength is obtained. Non, such problem is solved all.
[0025]
According to the anchor construction method of the present invention, not only can the construction of an anchor having a predetermined anchor strength be possible, even in the ground where the ground is moving rapidly such that the ground flows out of highly pressurized water, Anchors can also be easily constructed.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view shown in the order of construction according to an embodiment of the present invention.
FIG. 2 is a schematic explanatory diagram showing the next construction order of the embodiment of the present invention.
FIG. 3 is a schematic explanatory view showing the next construction order of the embodiment of the present invention.
FIG. 4 is a schematic explanatory view showing the next construction order of the embodiment of the present invention.
FIG. 5 is a schematic explanatory diagram showing still another construction order according to the embodiment of the present invention.
FIG. 6 is a partial perspective view of the uncurtain don according to the embodiment of the present invention.
FIG. 7 is a perspective view of the load-bearing body according to the embodiment of the present invention.
FIG. 8 is a cross-sectional view showing a conventional anchor construction method.
FIG. 9 is a partial perspective view of an uncurtain dong according to a conventional anchor construction method.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Uncurtain Don 2 Load-bearing body 3 Tensile material 6 Anchor hole 7 Anchor body 8 Bag body 16 Grout injection pipe 17 Sealing part 20 of bag body Opening pipe (casing)
21 Discard bit 22 Hose for grout injection 23 Hose for confirmation of grout filling (return hose)
24 Mouth Packer

Claims (1)

An anchor construction method comprising the following steps.
(1) A step of drilling an anchor hole to a predetermined depth at a predetermined angle using a drilling pipe having a discarded bit at the tip;
(2) Cover the fixing part of the uncurtain dong in advance with a woven cloth bag body, and insert the grout injection hose and the grout filling confirmation hose into the uncurtain dong, using the excavation pipe as a casing. Inserting step,
(3) A step of hitting a discarded bit at the tip of the casing with the inserted an curtainless detachment from the casing,
(4) a step of pulling out the casing so as not to damage the inserted an curtain curtain;
(5) A step of injecting a grout material into the bag by a grout injecting hose,
(6) a step of confirming a filling state of the grout material with a grout filling confirmation hose and closing the grout filling confirmation hose when a predetermined filling state is reached;
(7) Further, the grout material is pressurized and injected from the hose for injecting the grout, and the outer peripheral surface of the bag body is press-contacted to the hole wall of the anchor hole to improve the adhesion between the ground and the anchor fixing body. Closing the grout injection hose after pressure injection and solidifying the grout material,
(8) A step of stopping the mouth of the anchor hole with a mouth packer,
(9) A step of tensioning and fixing the tension material of the uncurtain don.

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