JPH11350477A - Ground surface side fixing device for ground anchor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stop water on the inside and outside of a casing more completely by closing the underground side end section of the casing with a sealant made of a swelling rubbery elastic material. SOLUTION: The anchor hole inside end section of a casing 27 is closed with a sealant 31. The sealant 31 is made of a swelling rubbery elastic material swelled when it contains water, and it is penetrated by a sheath 24a having a tentioning material 24. A cap 32 is put on the outside of an anchor head 28, and a rustproof material 33 made of grease is filled in the cap 32 and the casing 27. When underground water intrudes from the cracks generated on the anchor concrete 34 near the casing 27 or via the infiltration into the anchor concrete 34, the sealant 31 first absorbs water and is swelled. The sealing degree is increased by the pressure at the time of expansion, further infiltration of water into the casing 27 is blocked, and water is prevented from reaching a tentioning material anchoring section.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ground anchor for a ground anchor which has been subjected to rustproofing.

[0002]

2. Description of the Related Art Conventionally, there is a ground anchor shown in FIG. In this ground anchor, an anchor tension member 3 inserted into a sheath 2 is inserted into an anchor hole 1 excavated in the ground, and the inside of the anchor hole 1 of the tension member 3 is fixed to an inner fixing body (not shown).
Then, the ground surface side is led out to the opening of the anchor hole 1, the tension member 3 penetrates the supporting plate 4 abutting outside the opening, and is fixed by the fixing device 5.

In order to prevent the fixing portion from rusting, a cylindrical casing 6 is protruded from the support plate 4 and the rear end thereof is sealed with a sealing material 7.
The cap 8 is put on the outside of the support plate 4 and grout 9 is injected into the cap 8 and the casing 6.

[0004] The grout 9 has an anchor tensile material removed,
When re-tension is required, a fluid rust inhibitor such as grease is used, and in other cases, a solidifying agent such as cement milk is used.

[0005]

Such a conventional ground anchor surface fixing device for a ground anchor uses a rust preventive agent which does not solidify when removal of an anchor tensile material or re-tensioning is required. However, in this case, the sealing material 7 includes
Conventionally, a rubber plate or the like is used, but with this sealing method, there is a case where a perfect seal is not permanently made,
There is a problem that the grout 9 is washed away or water enters the casing 8 to impair the rust prevention effect.

The present invention has been made in view of such a conventional problem, and even when a rust preventive having fluidity is used, the sealing is completed completely and the infiltration of the ground anchor on the surface side of the ground anchor is prevented. The purpose is to provide.

[0007]

SUMMARY OF THE INVENTION The features of the present invention for solving the conventional problems as described above and achieving the intended purpose are as follows.
A ground anchor that is fixed in an anchor hole excavated and formed in the ground, and the end of an anchor tensile material that is inserted and led out of a sheath is fixed to a supporting plate at the opening of the anchor hole via an anchor head. In the ground-side fixing device, a rust-preventive agent-containing casing is provided on the back side of the support plate, and the rust-preventive agent is sealed in the casing, and the casing expands by containing the inside of the underground end of the casing. That is, it is closed by a sealing material made of a swellable rubber-like elastic material.

[0008]

In this device, when water enters through the anchor concrete outside the casing and reaches the end of the casing, the sealing material expands with water, and the opening at the end of the casing is firmly closed. When a certain amount of water is contained, no more water is absorbed and water permeation is prevented.

When the rust preventive in the casing is a liquid material such as grease, the seal material expands, thereby preventing leakage of the rust preventive.

[0010]

Next, an embodiment of the present invention will be described with reference to FIGS.

In the figure, 21 is an anchor hole, and 22 is a concrete wall installed on the ground surface. Anchor hole 21
Inside, a hole inner fixing metal 23 is inserted at an interval,
A tension member 24 is wrapped around this, and both ends are anchor holes 21.
Is led out to the opening. The tensile member 23 is movably inserted into the synthetic resin sheath 24a in the longitudinal direction, and is wrapped around the fixing metal 23 inside the hole with the sheath 24a mounted.

Around the opening of the anchor hole 21, a stiffening plate 25 is embedded in the surface of the concrete wall 22, and a supporting plate 26 is joined to the surface side.

A cylindrical casing 27 projects from the back surface of the support plate 26 and is inserted into the anchor hole 21.
An anchor head 28 is joined to the surface side of the support plate 26 via a nut 29, and a tension member 24 penetrates through a fixing hole of the anchor head, and the tension member 24 is fixed in the fixing hole with a wedge 30. Let me. The sheath 24a is peeled off from the tension member 24 near the rear surface of the anchor head 28, and only the bare tension member 24 penetrates the anchor head 28.

The casing 27 has its anchor hole inside end closed with a sealing material 31. The seal material 31 is formed of a swellable rubber-like elastic material that expands when it contains water, and a sheath 24 a containing a tensile material 24 is penetrated therethrough.

On the other hand, a cap 32 is put on the outside of the anchor head 28, and the cap 32 and the casing 27 are filled with a rust preventive 33 made of grease.

In the figure, reference numeral 34 denotes an anchor concrete in which cement milk is poured and solidified.

In the ground anchor, when groundwater enters from a crack generated in the anchor concrete 34 near the casing 27 or penetrates into the anchor concrete 34, first, the sealing material 31 absorbs water and expands. The pressure at the time of this expansion increases the degree of sealing, prevents further inundation of the casing 27, and prevents water from reaching the tensile material fixing section.

[0018]

As described above, in the present invention, the underground end of the casing is closed with a sealing material made of a swellable rubber-like elastic material, so that the water stopping inside and outside the casing becomes more complete, Rust prevention at the ground-side fixing portion of the tensile material is complete. Even if the sheath moves within the sealing material due to the re-tensioning of the tension member, the rust prevention effect is not impaired, and it is naturally possible to relax the tension.

Further, when the rust preventive in the casing is a liquid material such as grease, the seal material expands, thereby preventing leakage of the rust preventive.

Further, even if the sealing material insertion position fluctuates in the radial direction due to the tension of the tensile material, the sealing material expands and deforms following the fluctuation, thereby preventing leakage of the sealing material and intrusion of water. .

[Brief description of the drawings]

FIG. 1 is an enlarged sectional view of a ground-side fixing portion of an example of a ground anchor according to the present invention.

FIG. 2 is a cross-sectional view of an underground fixing portion of an example of the ground anchor according to the present invention.

FIG. 3 is a cross-sectional view of a ground-side fixing portion of a conventional ground anchor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 21 Anchor hole 22 Concrete wall 23 Fixing hardware 24 Tensile material 24a Synthetic resin sheath 25 Stiffening plate 26 Support plate 27 Casing 28 Anchor head 29 Nut 30 Wedge 31 Seal material 32 Cap 33 Rust inhibitor 34 Anchor concrete

Claims (1)

[Claims] 1. An end of an anchor tensile member fixed in an anchor hole excavated and formed in the ground, inserted through a sheath, and fixed to a supporting plate at the opening of the anchor hole via an anchor head. In the ground-side fixing device of the ground anchor, a rust-preventive agent-containing casing is provided on the back side of the support plate, the rust-preventive agent is sealed in the casing, and the inside of the underground end of the casing contains water. A ground-side fixing device for a ground anchor, characterized in that the ground anchor is closed with a sealing material made of a swellable rubber-like elastic material that expands when the ground anchor is closed.