JP7189648B2 - ground anchor - Google Patents

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JP7189648B2
JP7189648B2 JP2019109345A JP2019109345A JP7189648B2 JP 7189648 B2 JP7189648 B2 JP 7189648B2 JP 2019109345 A JP2019109345 A JP 2019109345A JP 2019109345 A JP2019109345 A JP 2019109345A JP 7189648 B2 JP7189648 B2 JP 7189648B2
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gripping
tension member
ground
hollow
shaft
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登 三上
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Nittoc Constructions Co Ltd
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Description

本発明は，引張材を地盤に定着し，緊張力を与えることにより斜面の安定，基礎の補強等を図るグラウンドアンカーに関する。 The present invention relates to a ground anchor that stabilizes slopes and reinforces foundations by fixing tensile members to the ground and applying tension.

グラウンドアンカー１００では，図１１で示す様に，地上側から延在している引張材１０１の地中側端部側をセメントグラウトＣにより不動地盤ＧＡに定着させ，引張力を付与する。そして地上側の端部（アンカーヘッド側の端部：図１１では左端部）は，アンカープレート１０３を介してナット１０２で固定している。図１１において，符号１０４は上部マンション，符号１０５は下部マンション，符号１０６はキャップ（ケーシング）を示している。
図１１において，グランドアンカー１００は，不動地盤ＧＡ中に延在するアンカー体長部１００Ａ，移動土塊ＧＢから地表近傍の法面工ＧＣに亘って延在する自由長部１００Ｂを有している。 In the ground anchor 100, as shown in FIG. 11, the underground side end side of the tensile member 101 extending from the ground side is fixed to the immovable ground GA by the cement grout C, and tensile force is applied. The end on the ground side (the end on the anchor head side: the left end in FIG. 11) is fixed with a nut 102 via an anchor plate 103 . In FIG. 11, reference numeral 104 denotes an upper apartment, reference numeral 105 denotes a lower apartment, and reference numeral 106 denotes a cap (casing).
In FIG. 11, the ground anchor 100 has an anchor body length portion 100A extending into the immovable ground GA, and a free length portion 100B extending from the moving earth mass GB over the slope work GC near the ground surface.

ここで引張材１０１が錆等により劣化してしまうと，グラウンドアンカー１００により斜面の安定，基礎の補強等を図ることは困難である。そのため，劣化した或いは劣化する恐れがある引張材を新しい引張材に交換することが望ましい。
しかし，従来技術では，引張材よりも早期に劣化する頭部のみを検査して，頭部を交換するのが一般的であった。
引張材を除去可能な除去式アンカー（例えば，特許文献１参照）も存在するが，従来の除去式アンカーでは，古くて劣化した（或いは劣化の恐れがある）引張材に代えて，新しい引張材を配置，施工すること（再配置すること）は出来ない。 Here, if the tensile member 101 deteriorates due to rust or the like, it is difficult to stabilize the slope and reinforce the foundation with the ground anchor 100 . Therefore, it is desirable to replace tension members that have deteriorated or are likely to deteriorate with new tension members.
However, in the prior art, it was common to inspect only the head that deteriorated earlier than the tensile member and replace the head.
There are also removable anchors that can remove the tension material (see, for example, Patent Document 1), but in conventional removable anchors, new tension materials are used instead of old and deteriorated (or likely to deteriorate) tension materials. cannot be placed or constructed (relocated).

特開２００６－２２５８８７号公報JP 2006-225887 A

本発明は上述した従来技術の問題点に鑑みて提案されたものであり，劣化した或いは劣化の恐れがある引張材に代えて，新しい引張材を再配置することが出来るグラウンドアンカーの提供を目的としている。 SUMMARY OF THE INVENTION The present invention has been proposed in view of the above-mentioned problems of the prior art, and it is an object of the present invention to provide a ground anchor that can be replaced with a new tension member in place of the tension member that has deteriorated or is likely to deteriorate. and

本発明のグラウンドアンカー（１０）は，
下部マンション（３）の中空部（３Ａ）に地中側が拡径する下部マンションテーパー部（３Ｂ）が形成されており，
引張材（１）の半径方向内側には中空部（１Ａ）が形成され，当該中空部（１Ａ）には把持部用軸（２）が配置されており，
把持部用軸（２）の地中側先端には地上側に向かって縮径する把持部側テーパー部（２Ｂ）を設けた把持部（２Ａ）が形成されており，
（把持部用軸２が地上側に引っ張られると）把持部（２Ａ）のテーパー部（２Ｂ）が引張材（１）の中空部（１Ａ）に係合して引張材（１）の地中側端部（１Ｂ）が拡径しており，当該拡径した引張材（１）の地中側端部（１Ｂ）が下部マンション（３）の中空部（３Ａ）における下部マンションテーパー部（３Ｂ）と係合していることを特徴としている。 The ground anchor (10) of the present invention is
A lower condominium tapered portion (3B) whose diameter is expanded on the underground side is formed in the hollow portion (3A) of the lower condominium (3),
A hollow portion (1A) is formed inside the tensile member (1) in the radial direction, and a grip portion shaft (2) is arranged in the hollow portion (1A),
A gripping portion (2A) provided with a gripping portion side tapered portion (2B) tapered toward the ground side is formed at the tip of the underground side of the gripping portion shaft (2),
(When the shaft 2 for gripping portion is pulled to the ground side) The tapered portion (2B) of the gripping portion (2A) engages with the hollow portion (1A) of the tensile member (1) to pull the tensile member (1) underground. The side end (1B) is expanded in diameter, and the underground side end (1B) of the expanded tension member (1) is the lower apartment taper portion (3B) in the hollow portion (3A) of the lower apartment (3). ) are engaged.

本発明のグラウンドアンカー（１０）の実施に際して，引張材（１）としては，例えばＰＣ鋼線，鋼棒が好ましく，錆びて劣化する恐れのある引張材に適用されるのが好ましい。ただし，例えばカーボン繊維の様に劣化せず（錆びることがなく），交換の必要性に乏しい引張材であっても，本発明を適用することは可能である。
また，本発明の引張材（１）は，モノストランドタイプの引張材（ナット定着或いはくさび・ナット併用定着する引張材）に適用されるのが好ましい。ただし，マルチストランドタイプの引張材に適用することも考えられる。
さらに本発明の実施に際して，前記把持部用軸（２）は，その一端に作用した押圧力が他端に確実に伝達される程度の剛性を有しているのが好ましい。 When implementing the ground anchor (10) of the present invention, the tensile member (1) is preferably, for example, a PC steel wire or a steel bar, and is preferably applied to a tensile member that may rust and deteriorate. However, it is possible to apply the present invention even to a tension member that does not deteriorate (corrodes) and does not need to be replaced much, such as carbon fiber.
Moreover, the tensile member (1) of the present invention is preferably applied to a mono-strand type tensile member (a tensile member fixed by a nut or a wedge and nut together). However, it is also conceivable to apply it to multi-strand type tensile bars.
Furthermore, in carrying out the present invention, it is preferable that the shaft for gripping portion (2) has such rigidity that the pressing force applied to one end thereof is reliably transmitted to the other end.

本発明のグラウンドアンカー工法では，
下部マンション（３）の中空部（３Ａ）に地中側が拡径する下部マンションテーパー部（３Ｂ）が形成されており，
引張材（１）の半径方向内側には中空部（１Ａ）が形成され，当該中空部（１Ａ）には把持部用軸（２）が配置されており，
把持部用軸（２）の地中側先端には地上側に向かって縮径する把持部側テーパー部（２Ｂ）を設けた把持部（２Ａ）が形成されており，
把持部用軸（２）が地上側に引っ張られると把持部（２Ａ）のテーパー部（２Ｂ）が引張材（１）の中空部（１Ａ）に係合して引張材（１）の地中側端部（１Ｂ）が拡径し，当該拡径した引張材（１）の地中側端部（１Ｂ）が下部マンション（３）の中空部（３Ａ）における下部マンションテーパー部（３Ｂ）と係合するグラウンドアンカー（１０）における引張材（１）を除去するに際して，
把持部用軸（２）を地中側に押圧して，引張材（１）の中空部（１Ａ）に対して把持部（２Ａ）のテーパー部（２Ｂ）を係合解除せしめる工程と，
把持部（２Ａ）のテーパー部（２Ｂ）が引張材（１）の中空部（１Ａ）に対して係合解除した状態で，把持部用軸（２）と引張材（１）を同時に地上側に引っ張る工程を備えている。
ここで，把持部（２Ａ）と係合解除した状態の引張材（１）と把持部用軸（２）は，シース材（４）の内側を介して地上側まで移動するのが好ましい。 In the ground anchor construction method of the present invention,
A lower condominium tapered portion (3B) whose diameter is expanded on the underground side is formed in the hollow portion (3A) of the lower condominium (3),
A hollow portion (1A) is formed inside the tensile member (1) in the radial direction, and a grip portion shaft (2) is arranged in the hollow portion (1A),
A gripping portion (2A) provided with a gripping portion side tapered portion (2B) tapered toward the ground side is formed at the tip of the underground side of the gripping portion shaft (2),
When the shaft for gripping portion (2) is pulled to the ground side, the tapered portion (2B) of the gripping portion (2A) engages with the hollow portion (1A) of the tensile member (1) to push the tensile member (1) underground. The side end portion (1B) is expanded in diameter, and the underground side end portion (1B) of the expanded tension member (1) forms the lower apartment taper portion (3B) in the hollow portion (3A) of the lower apartment (3). In removing the tension member (1) on the engaging ground anchor (10),
a step of disengaging the tapered portion (2B) of the gripping portion (2A) from the hollow portion (1A) of the tensile member (1) by pressing the gripping portion shaft (2) toward the ground;
With the taper part (2B) of the grip part (2A) disengaged from the hollow part (1A) of the tension member (1), the grip part shaft (2) and the tension member (1) are simultaneously pulled toward the ground. It is equipped with a process of pulling to
Here, it is preferable that the tension member (1) disengaged from the gripping portion (2A) and the gripping portion shaft (2) move to the ground side through the inside of the sheath member (4).

また本発明のグラウンドアンカー工法では，
下部マンション（３）の中空部（３Ａ）に地中側が拡径する下部マンションテーパー部（３Ｂ）が形成されており，
引張材（１）の半径方向内側には中空部（１Ａ）が形成され，当該中空部（１Ａ）には把持部用軸（２）が配置されており，
把持部用軸（２）の地中側先端には地上側に向かって縮径する把持部側テーパー部（２Ｂ）を設けた把持部（２Ａ）が形成されており，
把持部用軸（２）が地上側に引っ張られると把持部（２Ａ）のテーパー部（２Ｂ）が引張材（１）の中空部（１Ａ）に係合して引張材（１）の地中側端部（１Ｂ）が拡径し，当該拡径した引張材（１）の地中側端部（１Ｂ）が下部マンション（３）の中空部（３Ａ）における下部マンションテーパー部（３Ｂ）と係合するグラウンドアンカー（１０）における引張材（１）を再配置するに際して，
把持部用軸（２）を引張材（１）中央に配置し且つ把持部（２Ａ）のテーパー部（２Ｂ）が引張材（１）の中空部（１Ａ）に対して係合していない状態で，把持部用軸（２）と引張材（１）をシース材（４）の内部に挿入する工程と，
引張材（１）先端が下部マンションテーパー部（３Ｂ）に到達し且つ把持部（２Ａ）が下部マンションテーパー部（３Ｂ）よりも地中側に位置したならば把持部用軸（２）を地上側に引張り，把持部（２Ａ）のテーパー部（２Ｂ）を引張材（１）の中空部（１Ａ）に係合させて引張材（１）の地中側端部（１Ｂ）を拡径し，当該拡径した引張材（１）の地中側端部（１Ｂ）が下部マンション（３）の中空部（３Ａ）における下部マンションテーパー部（３Ｂ）と係合することを特徴としている。 In addition, in the ground anchor construction method of the present invention,
A lower condominium tapered portion (3B) whose diameter is expanded on the underground side is formed in the hollow portion (3A) of the lower condominium (3),
A hollow portion (1A) is formed inside the tensile member (1) in the radial direction, and a grip portion shaft (2) is arranged in the hollow portion (1A),
A gripping portion (2A) provided with a gripping portion side tapered portion (2B) tapered toward the ground side is formed at the tip of the underground side of the gripping portion shaft (2),
When the shaft for gripping portion (2) is pulled to the ground side, the tapered portion (2B) of the gripping portion (2A) engages with the hollow portion (1A) of the tensile member (1) to push the tensile member (1) underground. The side end portion (1B) is expanded in diameter, and the underground side end portion (1B) of the expanded tension member (1) forms the lower apartment taper portion (3B) in the hollow portion (3A) of the lower apartment (3). In repositioning the tension member (1) on the mating ground anchor (10),
A state in which the gripping shaft (2) is placed in the center of the tension member (1) and the tapered portion (2B) of the gripping portion (2A) is not engaged with the hollow portion (1A) of the tension member (1). a step of inserting the grip portion shaft (2) and the tension member (1) into the sheath member (4);
When the tip of the tensile member (1) reaches the lower apartment taper portion (3B) and the grip portion (2A) is located on the underground side of the lower apartment taper portion (3B), the grip portion shaft (2) is placed on the ground. Pull it to the side, engage the tapered part (2B) of the grip part (2A) with the hollow part (1A) of the tension member (1), and expand the diameter of the underground side end (1B) of the tension member (1). , The underground side end (1B) of the expanded tensile member (1) engages with the lower apartment taper portion (3B) in the hollow portion (3A) of the lower apartment (3).

上述の構成を具備する本発明によれば，下部マンション（３）の中空部（３Ａ）に地中側が拡径する下部マンションテーパー部（３Ｂ）が形成されており，把持部用軸（２）が地上側に引っ張られると把持部（２Ａ）のテーパー部（２Ｂ）が引張材（１）の中空部（１Ａ）に係合して引張材（１）の地中側端部（１Ｂ）が拡径され，当該拡径した引張材（１）の地中側端部（１Ｂ）が下部マンション（３）の中空部（３Ａ）における下部マンションテーパー部（３Ｂ）と係合するため，把持部（２Ａ）のテーパー部（２Ｂ）のくさび作用により引張材（１）の地中側先端（１Ｂ）が拡径して下部マンション（３）のテーパー部（３Ｂ）と強固に係合する（いわゆる「グリップ」した状態になる）。
そのため，引張材（１）に緊張力を付加しても，下部マンション（３）から引張材（１）が外れることは防止される。 According to the present invention having the above configuration, the lower apartment taper portion (3B) is formed in the hollow portion (3A) of the lower apartment (3) so that the diameter of the lower apartment (3) increases on the underground side. is pulled to the ground side, the taper part (2B) of the grip part (2A) engages with the hollow part (1A) of the tensile member (1), and the underground side end (1B) of the tensile member (1) is Since the diameter-expanded underground end (1B) of the expanded tensile member (1) engages with the lower apartment taper (3B) in the hollow (3A) of the lower apartment (3), the gripping portion Due to the wedge action of the tapered portion (2B) of (2A), the underground side tip (1B) of the tensile member (1) expands in diameter and firmly engages with the tapered portion (3B) of the lower apartment (3) (so-called "grip").
Therefore, even if tension is applied to the tension member (1), the tension member (1) is prevented from coming off from the lower condominium (3).

引張材（１）の地中側端部（１Ｂ）が下部マンション（３）の中空部（３Ａ）における下部マンションテーパー部（３Ｂ）と係合した状態において，引張部材（１）に作用する緊張力を解除した後，把持部用軸（２）を地中側に押圧すれば，把持部用軸（２）の剛性により当該押し込み力が地中側先端まで伝達され，把持部（２Ａ）のテーパー部（２Ｂ）が引張材（１）の地中側先端（１Ｂ）における中空部分（１Ａ）から外れ，引張材（１）の弾性反撥力により引張材（１）の地中側端部（１Ｂ）は拡径されていない状態に復帰し，把持部（２Ａ）と係合解除した状態の引張材（１）と把持部用軸（２）の径寸法はシース材（４）の内径寸法よりも小さくなる。その状態で把持部用軸（２）と引張材（１）を同時に地上側に引っ張れば，シース材（４）の内側を介して地上側まで移動することが出来る。 The tension acting on the tensile member (1) with the underground end (1B) of the tensile member (1) engaged with the lower apartment taper (3B) in the hollow (3A) of the lower apartment (3). After the force is released, if the gripping shaft (2) is pushed toward the ground, the pushing force is transmitted to the tip of the gripping portion (2A) due to the rigidity of the gripping shaft (2). The taper part (2B) is separated from the hollow part (1A) at the tip (1B) of the tensile member (1) on the underground side, and the elastic repulsive force of the tensile member (1) causes the end (1) on the underground side of the tensile member (1) 1B) returns to a non-expanded state, and the diameter dimension of the tensile member (1) and gripping shaft (2) in a state of disengagement from the gripping portion (2A) is the inner diameter dimension of the sheath material (4). be smaller than In this state, if the gripping shaft (2) and tension member (1) are simultaneously pulled to the ground side, they can be moved to the ground side through the inside of the sheath member (4).

ここで，引張材（１）を地上側に引き抜いた際に，引張材（１）のシース材（４）は地中に残存している。
新しい引張材（１）の中央に把持部用軸（２）を配置して，把持部（２Ａ）のテーパー部（２Ｂ）が引張材（１）の中空部（１Ａ）に対して係合していない状態であれば，引張材（１）と把持部用軸（２）の径寸法はシース材（４）の内径寸法よりも小さいため，把持部用軸（２）と引張材（１）をシース材（４）の内部に挿入することが出来る。
把持部用軸（２）と引張材（１）をシース材（４）の内部に挿入し，引張材先端（地中側端部１Ｂ）が下部マンションテーパー部（３Ｂ）に到達し且つ把持部（２Ａ）が下部マンションテーパー部（３Ｂ）よりも地中側に位置した際に，把持部用軸（２）を地上側に引っ張れば，把持部（２Ａ）のテーパー部（２Ｂ）が引張材（１）の中空部（１Ａ）に係合して引張材（１）の地中側端部（１Ｂ）を拡径する。当該拡径した引張材（１）の地中側端部（１Ｂ）は下部マンション（３）の中空部（３Ａ）における下部マンションテーパー部（３Ｂ）と係合し，把持部（２Ａ）のテーパー部（２Ｂ）のくさび作用により引張材（１）の地中側端部（１Ｂ）が拡径して，下部マンション（３）のテーパー部（３Ｂ）と強固に係合する（いわゆる「グリップ」した状態になる）。
係る状態であれば，引張材（１）に緊張力を付加しても下部マンション（３）から引張材（１）が外れることは防止される。 Here, when the tension member (1) is pulled out to the ground side, the sheath material (4) of the tension member (1) remains in the ground.
Place the shaft (2) for the gripping part in the center of the new tension member (1) so that the tapered part (2B) of the gripping part (2A) engages the hollow part (1A) of the tension member (1). If not, the diameter of the tension member (1) and the gripping shaft (2) is smaller than the inner diameter of the sheath (4), so the gripping shaft (2) and the tension member (1) can be inserted inside the sheath (4).
The gripping shaft (2) and the tension member (1) are inserted into the sheath material (4), and the tip of the tension member (ground side end 1B) reaches the lower apartment taper portion (3B) and the gripping portion When (2A) is located on the underground side of the lower condominium taper part (3B), if the grip part shaft (2) is pulled to the ground side, the taper part (2B) of the grip part (2A) is a tensile member. The diameter of the underground side end (1B) of the tension member (1) is expanded by engaging with the hollow portion (1A) of (1). The underground side end (1B) of the expanded tensile member (1) engages with the lower apartment taper portion (3B) in the hollow portion (3A) of the lower apartment (3), and the taper of the grip portion (2A). Due to the wedge action of the portion (2B), the underground side end portion (1B) of the tensile member (1) expands in diameter and firmly engages with the tapered portion (3B) of the lower apartment (3) (so-called "grip"). state).
In such a state, even if tension is applied to the tension member (1), the tension member (1) is prevented from coming off from the lower condominium (3).

本発明の実施形態に係るグラウンドアンカーのアンカー体長部を示す拡大断面図である。Fig. 4 is an enlarged cross-sectional view showing the anchor body length portion of the ground anchor according to the embodiment of the present invention; 実施形態における引張材と把持部用ロッドの配置を示す断面斜視図である。It is a cross-sectional perspective view which shows arrangement|positioning of the tension member and the rod for holding parts in embodiment. 実施形態に係るグラウンドアンカーの頭部近傍を示す拡大断面図である。It is an expanded sectional view which shows the vicinity of the head of the ground anchor which concerns on embodiment. 引張材を地上側に抜き取る工程を示す工程図である。It is process drawing which shows the process which pulls out a tension member to the ground side. 図４に続く工程を示す工程図である。FIG. 5 is a process chart showing a process following FIG. 4; 図５に続く工程を示す工程図である。FIG. 6 is a process drawing showing a process following FIG. 5 ; 図６に続く工程を示す工程図である。FIG. 7 is a process chart showing a process following FIG. 6; 再配置するべき引張材を下部マンションに係合させる一工程を示す工程図である。FIG. 10 is a process diagram showing one step of engaging the tension member to be repositioned to the lower apartment. 引張材を地上側に抜き取る手順を示すフローチャートである。It is a flowchart which shows the procedure which extracts a tension member to the ground side. 新しい引張材を下部マンションに係合させる手順を示すフローチャートである。Fig. 10 is a flow chart showing a procedure for engaging a new tension member to the lower condominium; グラウンドアンカーの概要を示す説明図である。It is an explanatory view showing an outline of a ground anchor.

以下，添付図面を参照して，本発明の実施形態について説明する。
図１において，図示の実施形態に係るグラウンドアンカー１０は，シース材４の内側空間を地上側（図１で右側）から地中側（図１で左側）に延在する引張材１と，引張材１の半径方向内側に形成された中空部１Ａ内に配置される把持部用軸２（把持部用ロッド）と，アンカー体長部１０Ａ（拘束長さ部）の地中側端部に配置される下部マンション３を有しており，図示しない固化材（セメントグラウト等）により不動地盤ＧＡ（図１１参照：図１では図示せず）に定着されている。引張材１は，シース材４に内包されており，且つ，防錆剤（グリース）が塗布されている。
下部マンション３には中空部３Ａが形成されており，中空部３Ａには引張材１及び把持部用ロッド２（把持部用軸）の地中側端部（図１では左端部）が収容されている。さらに中空部３Ａには，地中側が拡径する下部マンションテーパー部３Ｂが形成されている。 Embodiments of the present invention will be described below with reference to the accompanying drawings.
In FIG. 1, the ground anchor 10 according to the illustrated embodiment includes a tension member 1 extending from the ground side (right side in FIG. 1) to the ground side (left side in FIG. 1) in the inner space of the sheath member 4, and a tension member 1 The shaft 2 (rod for the gripping portion) arranged in the hollow portion 1A formed radially inside the material 1 and the anchor body long portion 10A (restraint length portion) arranged at the underground side end portion. It has a lower condominium 3, which is fixed to the immovable ground GA (see FIG. 11: not shown in FIG. 1) by a solidifying material (cement grout, etc.) not shown. The tensile member 1 is enclosed in a sheath member 4 and coated with a rust inhibitor (grease).
A hollow portion 3A is formed in the lower condominium 3. The hollow portion 3A accommodates the underground side end portion (the left end portion in FIG. 1) of the tensile member 1 and the rod 2 for the grip portion (shaft for the grip portion). ing. Further, the hollow portion 3A is formed with a lower apartment taper portion 3B whose diameter is increased on the underground side.

把持部用ロッド２の地中側先端には把持部２Ａが形成されており，把持部２Ａには地上側に向かって縮径する（或いは，地中側に向かって拡径する）把持部側テーパー部２Ｂが形成されている。
図１で示す様に，引張材１の地中側端部１Ｂが下部マンションテーパー部３Ｂの位置にある状態で，把持部用ロッド２が地上側（矢印Ｚ方向）に引っ張られると，把持部２Ａのテーパー部２Ｂが引張材１の中空部１Ａに係合して引張材１の地中側端部１Ｂをテーパー２Ｂと同様なテーパー状に拡径する。そして，当該テーパー状に拡径した引張材１の地中側端部１Ｂは，下部マンション３の中空部３Ａにおける下部マンションテーパー部３Ｂと係合する。
テーパー状に拡径した引張材１の地中側端部１Ｂが下部マンションテーパー部３Ｂと係合した状態では，くさび作用により，テーパー状に拡径した地中側先端１Ｂが下部マンション３のテーパー部３Ｂと強固に係合して，いわゆる「グリップ」した状態になる。係る「グリップ」した状態において，引張材１に地上側方向Ｚへの引張力を付加しても，下部マンション３から引張材１が外れることは防止される。 A gripping portion 2A is formed at the tip of the gripping portion rod 2 on the underground side, and the gripping portion side of the gripping portion 2A decreases in diameter toward the ground side (or expands in diameter toward the ground side). A tapered portion 2B is formed.
As shown in FIG. 1, with the underground side end 1B of the tensile member 1 located at the lower apartment taper portion 3B, when the rod 2 for the gripping portion is pulled to the ground side (in the direction of arrow Z), the gripping portion The tapered portion 2B of 2A is engaged with the hollow portion 1A of the tensile member 1 to expand the underground side end portion 1B of the tensile member 1 into a tapered shape similar to the taper 2B. The underground side end portion 1B of the tensile member 1 having a tapered diameter is engaged with the lower condominium tapered portion 3B in the hollow portion 3A of the lower condominium 3 .
In a state where the underground side end portion 1B of the tapered tension member 1 is engaged with the lower condominium taper portion 3B, the tapered underground side tip 1B tapers the lower condominium 3 due to the wedge action. It firmly engages with the portion 3B and is in a so-called "gripped" state. In such a "gripped" state, even if a tensile force is applied to the tension member 1 in the direction Z on the ground side, the tension member 1 is prevented from coming off the lower condominium 3.

図１におけるグラウンドアンカー１０の引張材１と把持部用ロッド２は，例えば図２で示す様に，引張材１を一般的なＰＣ鋼より線１－１とした場合に（複数のＰＣ鋼より線：図２では中央を除く６本がＰＣ鋼より線１－１），捻られず且つ螺旋形に撚られることなく，直線的に配置される中央の１本を，従来のＰＣ鋼線に代えて，剛性の高い把持部材用ロッド２に置換して構成されている。すなわち，図示の実施形態における引張材１と把持部用ロッド２では，図２において，通常の７本のＰＣ鋼より線１－１における中央の１本（中空部１ＡにおけるＰＣ鋼線）を，把持部用ロッド２に置換している。係る引張材１及び把持部用ロッド２は，シース材４により包囲されている。
ここで，図示の実施形態における引張材１は，例えばＰＣ鋼線，鋼棒の様に，錆びて劣化する恐れのある引張材で構成されている。しかし，例えばカーボン繊維の様に劣化せず（錆びることがなく），交換する必要性に乏しい引張材であっても本発明を適用することは可能である。 The tension member 1 and the rod 2 for the grip part of the ground anchor 10 in FIG. Wires: In Fig. 2, six wires except the center are PC steel wires 1-1), and the central one, which is arranged linearly without being twisted and helically twisted, is a conventional PC steel wire. Instead, it is configured by replacing with a gripping member rod 2 having high rigidity. That is, in the tension member 1 and the rod 2 for the grip part in the illustrated embodiment, in FIG. It is replaced with the rod 2 for the grip portion. The tension member 1 and the gripping rod 2 are surrounded by a sheath member 4 .
Here, the tensile member 1 in the illustrated embodiment is composed of a tensile member that may rust and deteriorate, such as PC steel wire or steel bar. However, it is possible to apply the present invention to a tensile material that does not deteriorate (corrodes) and that does not need to be replaced much, such as carbon fiber.

図３で示す図示の実施形態に係るグラウンドアンカー１０の頭部では，上部マンション５の外側部に雄ネジ部５Ａが形成されている。そして雄ネジ部５Ａは，グランドアンカー１０の地上側（図３で右側）端部において，図示しないアンカーヘッド（例えば図１１で示すナット１０２）の雌ネジ部と螺合し，以て，上部マンション５はグラウンドアンカー１０の地上側頭部に固定される。そしてアンカーヘッドを締め付けることにより，上部マンション５及び上部マンション５等に固定される把持部用ロッド２を地上側に引っ張り，引張材１に緊張力を付与している。
上部マンション５の半径方向内側に中空部５Ｂが形成され，中空部５Ｂよりも地上側（図３で右側）の領域には雌ネジ部５Ｃが形成されている。 In the head of the ground anchor 10 according to the illustrated embodiment shown in FIG. The male threaded portion 5A is screwed with the female threaded portion of an anchor head (not shown) (for example, the nut 102 shown in FIG. 11) at the ground side (right side in FIG. 3) end of the ground anchor 10. 5 is fixed to the side head of the ground anchor 10 on the ground. By tightening the anchor head, the upper condominium 5 and the gripping rod 2 fixed to the upper condominium 5 or the like are pulled to the ground side, and tension is applied to the tension member 1 .
A hollow portion 5B is formed inside the upper condominium 5 in the radial direction, and a female screw portion 5C is formed in a region on the ground side (right side in FIG. 3) of the hollow portion 5B.

上部マンション５より地中側（図３で左側）の領域には引張材１が接続しており，ここで引張材１はシース材４に包囲されている。図１で示す様に，引張材１の地中側端部は下部マンション３（図１）に接続されている。そして図１で示す様に，引張材１の半径方向内側には中空部１Ａが形成されており，中空部１Ａ内を把持部用ロッド２が延在している。
図３で示す様に把持部用ロッド２の地上側端部には雄ネジ部２Ｂが形成されており，雄ネジ部２Ｂが上部マンション５の雌ネジ部５Ｃと螺合することにより，把持部用ロッド２の地上側端部は上部マンション５に一体的に固定される。把持部用ロッド２は，上部マンション５の中空部５Ｂ及び引張材１の中空部１Ａの内部に延在している。把持部用ロッド２の地中側端部は，図１で示す状態では下部マンション３（図１参照）に固定されている。
なお，把持部用ロッド２の地上側端部が上部マンション５の雌ネジ部５Ｃに螺合することに代えて，把持部用ロッド２の地上側端部を，グラウンドアンカー１０における上部マンション５以外の地上側の部材（例えばアンカーヘッド等）に一体的に固定することも可能である。
図示の実施形態では，モノストランドタイプの引張材が対象であり，ナットによりアンカー頭部に定着されるタイプ，或いは，くさびとナットを併用してアンカー頭部に定着される引張材が対象となる。ただし，くさびによりアンカー頭部に定着されるマルチストランドタイプの引張材であっても，図示の実施形態或いは本発明を適用することも考えられる。 A tension member 1 is connected to an area on the underground side (left side in FIG. 3) of the upper condominium 5, and the tension member 1 is surrounded by a sheath member 4 here. As shown in FIG. 1, the underground side end of the tension member 1 is connected to the lower condominium 3 (FIG. 1). As shown in FIG. 1, a hollow portion 1A is formed inside the tensile member 1 in the radial direction, and a gripping rod 2 extends in the hollow portion 1A.
As shown in FIG. 3, a male threaded portion 2B is formed on the ground side end of the rod 2 for the grip portion. The ground-side end portion of the housing rod 2 is integrally fixed to the upper condominium 5 . The gripping rod 2 extends inside the hollow portion 5B of the upper apartment 5 and the hollow portion 1A of the tensile member 1 . In the state shown in FIG. 1, the underground side end of the gripping rod 2 is fixed to the lower condominium 3 (see FIG. 1).
Instead of screwing the ground-side end of the gripping rod 2 into the female threaded portion 5C of the upper apartment 5, the ground-side end of the gripping rod 2 is attached to the ground anchor 10 other than the upper apartment 5. It is also possible to integrally fix it to a member on the ground side (for example, an anchor head, etc.).
In the illustrated embodiment, the target is a mono-strand type tension member, and the target is a type that is fixed to the anchor head by a nut, or a tension member that is fixed to the anchor head using a wedge and a nut. . However, it is also conceivable to apply the illustrated embodiment or the present invention to a multi-strand type tension member fixed to the anchor head by a wedge.

次に，図４～図７及び図９を参照して，図示の実施形態において，グランドアンカー１０から劣化した或いは劣化の恐れのある引張材１を除去する態様を説明する。
図４～図７に示す工程を実行するに際して，グランドアンカー１０は，図１で示す様に，把持部用ロッド２が地上側（図１の矢印Ｚ方向）に引っ張られ，把持部２Ａのテーパー部２Ｂが引張材１の中空部１Ａに係合して引張材１の地中側端部１Ｂがテーパー状に拡径し，テーパー状に拡径した引張材１の地中側端部１Ｂが中空部３Ａにおける下部マンションテーパー部３Ｂと強固に係合して，いわゆる「グリップ」した状態になっており，引張材１に地上側方向の緊張力が付加されている。 Next, with reference to FIGS. 4 to 7 and 9, a manner of removing the tensile member 1 that has deteriorated or is likely to deteriorate from the ground anchor 10 in the illustrated embodiment will be described.
4 to 7, the ground anchor 10 is pulled, as shown in FIG. The portion 2B engages with the hollow portion 1A of the tensile member 1, the underground side end portion 1B of the tensile member 1 is tapered, and the underground side end portion 1B of the tapered tensile member 1 is expanded. The hollow portion 3A is firmly engaged with the lower mansion tapered portion 3B, and is in a so-called "gripped" state, and tension force is applied to the tensile member 1 in the ground direction.

引張材１を地上側に抜き取るに際して，図４で示す工程では，引張部材１に作用する緊張力は解除されている。そして実線の矢印Ａで示す様に，把持部用ロッド２を地中側（図４で左側）に押圧している。
把持部用ロッド２は高い剛性を有しているので，前記地中側に押圧される力は把持部用ロッド２の地中側先端まで伝達され，把持部用ロッド２は図４で示す状態よりも地中側（図４では左側）に移動する。すなわち，中空部３Ａにおける下部マンションテーパー部３Ｂに対して把持部２Ａのテーパー部２Ｂが地中側に移動し，引張材１の地中側先端１Ｂと把持部２Ａのテーパー部２Ｂの係合が解除される。 When pulling out the tension member 1 to the ground side, the tension acting on the tension member 1 is released in the process shown in FIG. Then, as indicated by a solid arrow A, the rod 2 for the grasping portion is pressed toward the ground (to the left in FIG. 4).
Since the gripping rod 2 has high rigidity, the force pressed toward the ground is transmitted to the tip of the gripping rod 2 on the ground side, and the gripping rod 2 is in the state shown in FIG. It moves to the underground side (left side in FIG. 4). That is, the tapered portion 2B of the gripping portion 2A moves toward the underground side with respect to the lower condominium tapered portion 3B in the hollow portion 3A, and the engagement between the underground side tip 1B of the tensile member 1 and the tapered portion 2B of the gripping portion 2A is disengaged. be released.

引張材１の地中側先端１Ｂから把持部２Ａの係合が解除される際に，図４で示す状態ではテーパー状に拡径していた引張材１の地中側端部１Ｂは，図５の実線の矢印Ｂで示す様に，引張材１の弾性反撥力により拡径されていない状態に復帰する。そして，引張材１の地中側端部１Ｂがテーパー状に拡径していない状態に復帰すれば，地中側端部１Ｂと下部マンションテーパー部３Ｂとの係合も解除される。
地中側端部１Ｂと下部マンションテーパー部３Ｂとの係合が解除されて引張材１の地中側端部１Ｂが拡径されていない状態に復帰すると，図６で示す様に，引張材１と把持部用ロッド２（把持部２Ａを含む）の径寸法は，図６の右端におけるシース材４の内径寸法（下部マンション３よりも地上側の領域におけるシース材４の内径寸法）よりも小さくなる。引張材１の地中側端部１Ｂが拡径されていない状態に復帰した状態（図６参照）で把持部用ロッド２と引張材１を同時に地上側に引っ張れば（実線矢印Ｃ），シース材４の内側を介して地上側まで移動することが出来る様になる。 When the gripping portion 2A is disengaged from the underground tip 1B of the tensile member 1, the underground-side end 1B of the tensile member 1, which has expanded in a tapered shape in the state shown in FIG. As indicated by the solid arrow B in 5, the elastic repulsive force of the tensile member 1 returns to the non-expanded state. When the underground side end portion 1B of the tensile member 1 returns to a state in which the tapered shape is not expanded, the engagement between the underground side end portion 1B and the lower condominium tapered portion 3B is also released.
When the engagement between the underground side end portion 1B and the lower mansion taper portion 3B is released and the underground side end portion 1B of the tension member 1 returns to a state in which the diameter is not expanded, the tension member 1B is restored as shown in FIG. 1 and the gripping rod 2 (including the gripping portion 2A) are larger than the inner diameter of the sheath material 4 at the right end of FIG. become smaller. If the gripping rod 2 and the tension member 1 are simultaneously pulled to the ground side (solid arrow C) in a state where the underground side end portion 1B of the tension member 1 has returned to the state where the diameter is not expanded (see FIG. 6), the sheath Through the inside of the material 4, it becomes possible to move to the ground side.

図６の工程では，把持部２Ａのテーパー部２Ｂが引張材１の中空部１Ａ（の地中側端部１Ｂ）に対して係合解除した状態で，把持部用ロッド２と引張材１を同時に地上側に引っ張っている。
引張材１と把持部用ロッド２を同時に地上側に引っ張ることで，引張材１と把持部用ロッド２の相対位置を一定にして，引張材１と把持部用ロッド２と把持部２Ａの径寸法がシース材４の内径寸法よりも小さい状態を維持して，地上側への移動を妨げることが防止される。 In the process of FIG. 6, the rod 2 for the gripping portion and the tensioning member 1 are separated in a state in which the tapered portion 2B of the gripping portion 2A is disengaged from the hollow portion 1A (the end portion 1B on the underground side) of the tensioning member 1. At the same time, it pulls toward the ground.
By simultaneously pulling the tension member 1 and the grip rod 2 to the ground side, the relative positions of the tension member 1 and the grip rod 2 are kept constant, and the diameters of the tension member 1, the grip rod 2, and the grip portion 2A are adjusted. The dimension is kept smaller than the inner diameter dimension of the sheath material 4 to prevent hindrance to movement to the ground side.

図７は，把持部用ロッド２と引張材１を同時に，地上側（実線矢印Ｃ方向）に引っ張る工程を示しており，把持部用ロッド２と引張材１がシース材４の内側を移動している態様を示している。
図示はされていないが，交換するべき引張材１は把持部用ロッド２と共に地上側に引き出され，その際にシース材４を地中に残存させたままである。地上側に引き出された引張材は新しい引張材１と交換される。その際に，把持部用ロッド２も交換することが出来る。或いは，再利用することも可能である。 FIG. 7 shows the process of simultaneously pulling the gripping rod 2 and the tension member 1 toward the ground (in the direction of the solid arrow C). It shows an aspect that
Although not shown, the tension member 1 to be replaced is pulled out to the ground side together with the rod 2 for the grip portion, and the sheath member 4 remains in the ground at that time. The tension member pulled out to the ground side is replaced with a new tension member 1. At that time, the grip portion rod 2 can also be replaced. Alternatively, it can be reused.

図４～図７を参照して説明した引張材１の除去について，主として図９のフローチャートを参照して説明する。
図９において，ステップＳ１は図４，図５で説明した工程に対応しており，引張部材１の緊張力を解除した後，把持部用ロッド２を地中側に押圧する（図４の実線矢印Ａ）。
把持部用ロッド２を地中側に押圧すれば，把持部２Ａが引張材１の地中側先端１Ｂにおける中空部分１Ａから外れ，把持部２Ａのテーパー部２Ｂと引張材１の中空部１Ａのテーパー状に拡径した領域との係合が解除され，引張材１の地中側端部１Ｂはテーパー状に拡径されていない状態に復帰する。
引張材１の地中側端部１Ｂが拡径されていない状態に復帰すると，（図５の実線矢印Ｂで示す様に）引張材１はシース材４の内部を移動出来る程度まで縮径する。そのため，ステップＳ２では，把持部用ロッド２と引張材１を同時に地上側に引っ張り，下部マンション３の中空部３Ａ，シース材４の内側を介して，地上側まで移動する。 The removal of the tensile member 1 described with reference to FIGS. 4 to 7 will be described mainly with reference to the flow chart of FIG.
In FIG. 9, step S1 corresponds to the process explained in FIGS. 4 and 5, and after releasing the tension force of the tension member 1, the rod 2 for the gripping portion is pressed toward the ground (solid line in FIG. 4). Arrow A).
When the gripping rod 2 is pressed toward the ground, the gripping portion 2A is disengaged from the hollow portion 1A at the tip 1B of the tensile member 1 on the underground side, and the taper portion 2B of the gripping portion 2A and the hollow portion 1A of the tensile member 1 are separated. The engagement with the tapered expanded region is released, and the underground side end portion 1B of the tensile member 1 returns to a state where it is not tapered.
When the underground side end portion 1B of the tension member 1 returns to a state where the diameter is not expanded, the diameter of the tension member 1 is reduced to the extent that it can move inside the sheath member 4 (as indicated by the solid line arrow B in FIG. 5). . Therefore, in step S2, the gripping rod 2 and the tension member 1 are simultaneously pulled to the ground side and moved to the ground side via the hollow portion 3A of the lower apartment 3 and the inner side of the sheath member 4. FIG.

ステップＳ１において，引張材１の地中側端部１Ｂが拡径されていない状態に完全に復帰できていなくても，ステップＳ２で把持部用ロッド２と引張材１を地上側に引き込む際に，引張材１の地中側端部１Ｂは下部マンションテーパー部３Ｂと当接することにより縮径し，シース材４の内側を移動可能になる。
次のステップＳ３では，図６，図７に示す様に，把持部用ロッド２と引張材１はシース材４の内側（内部空間）を通過して地上側に移動する。そしてステップＳ４では，把持部用ロッド２及び引張材１は地上側に引き出され，劣化した引張材１或いは劣化の恐れのある引張材１を除去することが出来る。ここで，把持部用ロッド２について劣化或いは劣化の恐れがあれば，引張材１と共に除去する。 Even if the underground side end portion 1B of the tension member 1 has not completely returned to the non-expanded state in step S1, when the rod 2 for the gripping portion and the tension member 1 are pulled to the ground side in step S2, , the underground side end portion 1B of the tensile member 1 is contracted in diameter by coming into contact with the lower apartment taper portion 3B, and becomes movable inside the sheath member 4. As shown in FIG.
In the next step S3, as shown in FIGS. 6 and 7, the gripping rod 2 and the tension member 1 pass through the inside (internal space) of the sheath member 4 and move to the ground side. Then, in step S4, the gripping portion rod 2 and the tension member 1 are pulled out to the ground side, and the tension member 1 that has deteriorated or is likely to deteriorate can be removed. Here, if the rod 2 for the grip portion is deteriorated or is likely to be deteriorated, it is removed together with the tensile member 1 .

次に，劣化或いは劣化の恐れのある引張材１を（劣化或いは劣化の恐れがある把持部用ロッド２も同様に）グランドアンカー１０から除去した後，新しい引張材１を（把持部用ロッド２も除去した場合は新しい把持用ロッド２と共に）再配置して，下部マンションに係合する必要がある。係る係合する態様について，図１０のフローチャートを主として参照し，図７，図６，図８，図４をも参照して説明する。
図１０のステップＳ１１では，把持部用ロッド２を引張材１の中空部１Ａに配置する。そして，把持部２Ａのテーパー部２Ｂが引張材１の中空部１Ａに係合していない状態，すなわち把持部２Ａの分だけ把持部用ロッド２を引張材１よりも地中側に先行させた状態で，把持部用ロッド２と引張材１をシース材４の内部に挿入し，地中側に移動させる（図７，図６の破線矢印Ｄ参照）。 Next, after removing the tension member 1 that is likely to be deteriorated or deteriorated (as well as the rod 2 for the gripping portion that is likely to be deteriorated or deteriorated) from the ground anchor 10, a new tension member 1 (the rod for the gripping portion 2 (with a new gripping rod 2) to engage the lower apartment. This engagement mode will be described mainly with reference to the flowchart of FIG. 10, and also with reference to FIGS. 7, 6, 8 and 4.
In step S11 of FIG. 10, the rod 2 for gripping portion is placed in the hollow portion 1A of the tensile member 1. As shown in FIG. Then, the tapered portion 2B of the gripping portion 2A is not engaged with the hollow portion 1A of the tensile member 1, that is, the gripping portion rod 2 is advanced to the underground side of the tensile member 1 by the amount of the gripping portion 2A. In this state, the gripping rod 2 and tension member 1 are inserted into the sheath member 4 and moved to the underground side (see dashed arrow D in FIGS. 7 and 6).

把持部用ロッド２と引張材１をシース材４の内部を地中側に移動する工程は，図８で示す様に，引張材１の地中側端部１Ｂが下部マンション３のテーパー部３Ｂに到達し，把持部用ロッド２の把持部２Ａが下部マンションテーパー部３Ｂよりも地中側に位置するまで行われる。
図１０のステップＳ１２では，引張材１の地中側端部１Ｂ及び把持部２Ａが図８で示す状態となっている。 In the step of moving the gripping rod 2 and the tension member 1 to the underground side inside the sheath member 4, as shown in FIG. , and the gripping portion 2A of the rod for gripping portion 2 is positioned on the underground side of the lower apartment taper portion 3B.
In step S12 of FIG. 10, the underground side end portion 1B of the tensile member 1 and the grip portion 2A are in the state shown in FIG.

図８で示す状態となった後，ステップＳ１３で，把持部用ロッド２を地上側に引っ張る（図８の破線矢印Ｅ）。そして，把持部２Ａのテーパー部２Ｂを引張材１の中空部１Ａに係合させて引張材１の地中側端部１Ｂをテーパー状に拡径させ，テーパー状に拡径した地中側端部１Ｂを下部マンション３の下部マンションテーパー部３Ｂと係合せしめる。
把持部用ロッド２を地上側に引っ張って地中側端部１Ｂをテーパー状に拡径し，下部マンションテーパー部３Ｂと係合させた状態は，図４に示されている。
図４で示す状態において，図１０のステップＳ１４で，引張材１（及び把持部用ロッド２）に緊張力を付加する。
これにより，グランドアンカー１０における引張力１（及び把持部用ロッド２）の再配置が終了する。 After the state shown in FIG. 8 is reached, in step S13, the rod 2 for the grip portion is pulled toward the ground (broken line arrow E in FIG. 8). Then, the tapered portion 2B of the grip portion 2A is engaged with the hollow portion 1A of the tensile member 1 to expand the underground side end portion 1B of the tensile member 1 in a tapered shape, and the tapered underground side end portion is expanded in diameter. The portion 1B is engaged with the lower apartment taper portion 3B of the lower apartment 3.
FIG. 4 shows a state in which the rod 2 for the grip portion is pulled to the ground to expand the diameter of the underground side end portion 1B into a tapered shape and engage with the lower apartment taper portion 3B.
In the state shown in FIG. 4, in step S14 of FIG. 10, tension is applied to the tension member 1 (and the rod 2 for gripping portion).
This completes the rearrangement of the tensile force 1 (and the gripping rod 2) in the ground anchor 10. FIG.

図示の実施形態によれば，下部マンション３の中空部３Ａに地中側が拡径する下部マンションテーパー部３Ｂが形成されており，把持部用ロッド２が地上側に引っ張られると把持部２Ａのテーパー部２Ｂが引張材１の中空部１Ａに係合し，地中側端部１Ｂがテーパー状に拡径され，テーパー状に拡径した地中側端部１Ｂが下部マンションテーパー部３Ｂと係合する（いわゆる「グリップ」した状態になる）。
把持部２Ａのテーパー部２Ｂのくさび作用により拡径した引張材１の地中側先端１Ｂが下部マンションテーパー部３Ｂと強固に係合するので，引張材１に緊張力を付加しても，下部マンション３から引張材１が外れることは防止される。 According to the illustrated embodiment, the hollow portion 3A of the lower condominium 3 is formed with a lower condominium tapered portion 3B that expands in diameter on the underground side. The part 2B is engaged with the hollow part 1A of the tensile member 1, the underground side end part 1B is tapered and the tapered underground side end part 1B is engaged with the lower apartment taper part 3B. (becomes a so-called "grip" state).
The underground side tip 1B of the tensile member 1, which is expanded in diameter by the wedge action of the tapered portion 2B of the grip portion 2A, firmly engages with the lower apartment taper portion 3B. The tension member 1 is prevented from coming off from the apartment 3.

劣化或いは劣化の恐れのある引張材１を地上に抜き取って除去する際は，いわゆる「グリップ」した状態において，引張部材１に作用する緊張力を解除した後，把持部用ロッド２を地中側に押圧する。把持部用ロッド２の剛性により，当該押し込み力は地中側先端まで伝達され，把持部２Ａのテーパー部２Ｂが引張材１の地中側先端１Ｂにおける中空部分１Ａから外れる。テーパー部２Ｂが中空部分１Ａから外れると，引張材１の弾性反撥力により引張材１の地中側端部１Ｂは拡径されていない状態に復帰し，把持部２Ａと係合解除した状態の引張材１と把持部用ロッド２の径寸法は，下部マンション３の中空部３Ａの地上側端部近傍の内径寸法及びシース材４の内径寸法よりも小さくなる。
引張材１と把持部用ロッド２の径寸法が縮径した状態で把持部用ロッド２と引張材１を同時に地上側に引っ張れば，シース材４の内側を介して地上側まで移動し，地中側の領域から除去する（抜き取る）ことが出来る。 When pulling out the tension member 1 which is deteriorated or may be deteriorated to the ground and removes it, after releasing the tension acting on the tension member 1 in a so-called "grip" state, the rod 2 for the grip part is pushed to the ground side. press to. Due to the rigidity of the grip rod 2, the pushing force is transmitted to the underground tip, and the tapered part 2B of the grip 2A is disengaged from the hollow part 1A at the underground tip 1B of the tensile member 1. When the tapered portion 2B is separated from the hollow portion 1A, the elastic repulsive force of the tensile member 1 restores the ground side end portion 1B of the tensile member 1 to a state in which the diameter is not expanded, and the state of disengagement from the grip portion 2A. The diameters of the tensile member 1 and the gripping rod 2 are smaller than the inner diameter of the hollow portion 3A of the lower apartment 3 near the ground side end and the inner diameter of the sheath member 4 .
If the tension member 1 and the tension member 1 are pulled toward the ground at the same time while the diameters of the tension member 1 and the rod 2 for the grip are reduced, they move to the ground side through the inner side of the sheath member 4 and reach the ground. It can be removed (extracted) from the middle region.

新しい引張材１を再配置する際は，新しい引張材１の中央に把持部用ロッド２（把持部用軸）を配置する。この状態では，把持部２Ａのテーパー部２Ｂは引張材１の中空部１Ａに対して係合しておらず，引張材１の端部をテーパー状に拡径してはいないため，引張材１と把持部用ロッド２の径寸法はシース材４の内径寸法よりも小さく，シース材４の内部に挿入することが出来る。
把持部用ロッド２と引張材１をシース材４の内部に挿入し，引張材先端（地中側端部１Ｂ）が下部マンションテーパー部３Ｂに到達し且つ把持部２Ａが下部マンションテーパー部３Ｂよりも地中側に位置したならば，把持部用ロッド２を地上側に引っ張ることにより，把持部２Ａのテーパー部２Ｂが引張材１の中空部１Ａに係合して引張材１の地中側端部１Ｂをテーパー状に拡径させることが出来る。当該拡径した地中側端部１Ｂは下部マンション３の中空部３Ａにおける下部マンションテーパー部３Ｂと係合し，いわゆる「グリップ」した状態になる。そのため，引張材１の地中側端部１Ｂと下部マンション３のテーパー部３Ｂとは強固に係合する。
係る状態であれば，引張材１に緊張力を付加しても下部マンション３から引張材１が外れることは防止される。 When the new tension member 1 is repositioned, the grasping rod 2 (grasping portion shaft) is arranged in the center of the new tension member 1 . In this state, the tapered portion 2B of the grip portion 2A is not engaged with the hollow portion 1A of the tensile member 1, and the end portion of the tensile member 1 is not tapered. The diameter of the gripping rod 2 is smaller than the inner diameter of the sheath member 4 and can be inserted into the sheath member 4 .
The gripping portion rod 2 and the tension member 1 are inserted into the sheath member 4, the tip of the tensioning member (the underground side end portion 1B) reaches the lower apartment taper portion 3B, and the grip portion 2A extends from the lower apartment taper portion 3B. is located on the ground side, the tapered portion 2B of the gripping portion 2A is engaged with the hollow portion 1A of the tension member 1 by pulling the rod 2 for the gripping portion to the ground side, and the tension member 1 is pulled on the ground side. The diameter of the end portion 1B can be expanded in a tapered shape. The diameter-expanded underground side end portion 1B engages with the lower apartment tapered portion 3B in the hollow portion 3A of the lower apartment 3, and is in a so-called "grip" state. Therefore, the underground side end portion 1B of the tensile member 1 and the tapered portion 3B of the lower condominium 3 are firmly engaged.
In such a state, the tension member 1 is prevented from coming off from the lower condominium 3 even if tension is applied to the tension member 1 .

図示の実施形態はあくまでも例示であり，本発明の技術的範囲を限定する趣旨の記述ではないことを付記する。
例えば，引張材としては，ＰＣ鋼より線に限定されず，他のＰＣ鋼線，鋼棒を使用することもＰ可能である。 It should be noted that the illustrated embodiment is merely an example and is not intended to limit the technical scope of the present invention.
For example, tension members are not limited to PC steel stranded wires, and other PC steel wires and steel bars can also be used.

１・・・引張材
１Ａ・・・引張材の中空部
１Ｂ・・・引張材の地中側端部
２・・・把持部用ロッド（把持部用軸）
２Ａ・・・把持部
２Ｂ・・・把持部のテーパー部
３・・・下部マンション
３Ａ・・・下部マンションの中空部
３Ｂ・・・下部マンションテーパー部
４・・・シース材
１０・・・グラウンドアンカー Reference Signs List 1 Tension member 1A Hollow portion of tension member 1B Underground side end portion of tension member 2 Grasping portion rod (grasping portion shaft)
2A Grasping portion 2B Tapered portion of gripping portion 3 Lower apartment 3A Hollow portion of lower apartment 3B Lower apartment tapered portion 4 Sheath material 10 Ground anchor

Claims (3)

下部マンションの中空部に地中側が拡径する下部マンションテーパー部が形成されており，
引張材の半径方向内側には中空部が形成され，当該中空部には把持部用軸が配置されており，
把持部用軸の地中側先端には地上側に向かって縮径する把持部側テーパー部を設けた把持部が形成されており，
把持部のテーパー部が引張材の中空部に係合して引張材の地中側端部が拡径しており，当該拡径した引張材の地中側端部が下部マンションの中空部における下部マンションテーパー部と係合していることを特徴とするグラウンドアンカー。 A tapered portion of the lower condominium is formed in the hollow part of the lower condominium, where the underground side expands in diameter.
A hollow portion is formed inside the tensile member in the radial direction, and a shaft for the gripping portion is arranged in the hollow portion,
A gripping portion provided with a gripping portion side tapered portion whose diameter decreases toward the ground side is formed at the tip of the gripping portion shaft on the underground side.
The tapered part of the gripping part is engaged with the hollow part of the tension member, and the diameter of the underground side end of the tension member is expanded. A ground anchor in engagement with a lower mansion taper. 下部マンションの中空部に地中側が拡径する下部マンションテーパー部が形成されており，
引張材の半径方向内側には中空部が形成され，当該中空部には把持部用軸が配置されており，
把持部用軸の地中側先端には地上側に向かって縮径する把持部側テーパー部を設けた把持部が形成されており，
把持部用軸が地上側に引っ張られると把持部のテーパー部が引張材の中空部に係合して引張材の地中側端部が拡径し，当該拡径した引張材の地中側端部が下部マンションの中空部における下部マンションテーパー部と係合するグラウンドアンカーにおける引張材を除去するに際して，
把持部用軸を地中側に押圧して，引張材の中空部に対して把持部のテーパー部を係合解除せしめる工程と，
把持部のテーパー部が引張材の中空部に対して係合解除した状態で，把持部用軸と引張材を同時に地上側に引っ張る工程を備えていることを特徴とするグラウンドアンカー工法。 A tapered portion of the lower condominium is formed in the hollow part of the lower condominium, where the underground side expands in diameter.
A hollow portion is formed inside the tensile member in the radial direction, and a shaft for the gripping portion is arranged in the hollow portion,
A gripping portion provided with a gripping portion side tapered portion whose diameter decreases toward the ground side is formed at the tip of the gripping portion shaft on the underground side.
When the shaft for the gripping part is pulled to the ground side, the tapered part of the gripping part engages with the hollow part of the tension member, and the underground side end of the tension member expands in diameter, and the diameter of the expanded tension member expands to the underground side. In removing the tension member in the ground anchor whose end engages the lower apartment taper in the hollow of the lower apartment:
pressing the gripper shaft toward the ground to disengage the tapered portion of the gripper from the hollow portion of the tensile member;
A ground anchor construction method characterized by including a step of simultaneously pulling the shaft for the gripping portion and the tensioning member to the ground side in a state where the tapered portion of the gripping portion is disengaged from the hollow portion of the tensioning member. 下部マンションの中空部に地中側が拡径する下部マンションテーパー部が形成されており，
引張材の半径方向内側には中空部が形成され，当該中空部には把持部用軸が配置されており，
把持部用軸の地中側先端には地上側に向かって縮径する把持部側テーパー部を設けた把持部が形成されており，
把持部用軸が地上側に引っ張られると把持部のテーパー部が引張材の中空部に係合して引張材の地中側端部が拡径し，当該拡径した引張材の地中側端部が下部マンションの中空部における下部マンションテーパー部と係合するグラウンドアンカーにおける引張材を再配置するに際して，
把持部用軸を引張材中央に配置し且つ把持部のテーパー部が引張材の中空部に対して係合していない状態で，把持部用軸と引張材をシース材の内部に挿入する工程と，
引張材先端が下部マンションテーパー部に到達し且つ把持部が下部マンションテーパー部よりも地中側に位置したならば把持部用軸を地上側に引張り，把持部のテーパー部を引張材の中空部に係合させて引張材の地中側端部を拡径し，当該拡径した引張材の地中側端部が下部マンションの中空部における下部マンションテーパー部と係合することを特徴とするグラウンドアンカー工法。 A tapered portion of the lower condominium is formed in the hollow part of the lower condominium, where the underground side expands in diameter.
A hollow portion is formed inside the tensile member in the radial direction, and a shaft for the gripping portion is arranged in the hollow portion,
A gripping portion provided with a gripping portion side tapered portion whose diameter decreases toward the ground side is formed at the tip of the gripping portion shaft on the underground side.
When the shaft for the gripping part is pulled to the ground side, the tapered part of the gripping part engages with the hollow part of the tension member, and the underground side end of the tension member expands in diameter, and the diameter of the expanded tension member expands to the underground side. In repositioning the tension member in the ground anchor whose end engages the lower apartment taper in the hollow of the lower apartment:
A step of inserting the gripping shaft and the tensioning member into the sheath material in a state in which the gripping shaft is placed in the center of the tensioning member and the tapered portion of the gripping portion is not engaged with the hollow portion of the tensioning member. When,
When the tip of the tension member reaches the taper portion of the lower mansion and the grip portion is located on the underground side of the taper portion of the lower mansion, the shaft for the grip portion is pulled to the ground side, and the taper portion of the grip portion is pulled into the hollow portion of the tension member. The diameter of the underground side end of the tension member is expanded by engaging with the lower apartment, and the diameter of the expanded diameter of the underground side of the tension member is engaged with the lower apartment taper part in the hollow part of the lower apartment. ground anchor method.
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Citations (2)

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JP2005351028A (en) 2004-06-14 2005-12-22 Nittoc Constr Co Ltd Removal anchor method and its anchor tendon
JP2006225887A (en) 2005-02-15 2006-08-31 In-Kwi Lee Anchoring device for removal type anchor

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5523998B2 (en) * 1972-06-28 1980-06-26
JPS6049759B2 (en) * 1979-04-24 1985-11-05 鹿島建設株式会社 PC cable insertion device
JPH1121887A (en) * 1997-07-02 1999-01-26 Geo Front:Kk Ground anchor
JP2936476B1 (en) * 1998-04-10 1999-08-23 ブイ・エス・エル・ジャパン株式会社 Removal anchor

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005351028A (en) 2004-06-14 2005-12-22 Nittoc Constr Co Ltd Removal anchor method and its anchor tendon
JP2006225887A (en) 2005-02-15 2006-08-31 In-Kwi Lee Anchoring device for removal type anchor

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