JP3138646B2 - Wellhead packing - Google Patents
Wellhead packingInfo
- Publication number
- JP3138646B2 JP3138646B2 JP08286940A JP28694096A JP3138646B2 JP 3138646 B2 JP3138646 B2 JP 3138646B2 JP 08286940 A JP08286940 A JP 08286940A JP 28694096 A JP28694096 A JP 28694096A JP 3138646 B2 JP3138646 B2 JP 3138646B2
- Authority
- JP
- Japan
- Prior art keywords
- seal member
- wellhead
- packing
- diameter
- cover cylinder
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Landscapes
- Excavating Of Shafts Or Tunnels (AREA)
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、先導体が形成した
坑道に推進管を押し込む地中推進工法において使用され
る坑口パッキングに関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wellhead packing used in an underground propulsion method in which a propulsion pipe is pushed into a tunnel formed by a leading conductor.
【０００２】[0002]
【従来の技術】ケーブル等を延線するための推進管を地
中に埋設する地中推進工法のうち、崩壊性地盤や玉石混
じり地盤を含む広範囲な土質に対応できるものとして、
掘削・排土方式と呼ばれているものが知られている。図
１４に示すように、この地中推進工法は、まず推進計画
線Ｌのレベル以下に発進立坑１及び到達立坑２を掘り下
げた後、元押装置３を発進立坑１に据え付けると共に、
カッタヘッド４を備えた先導体５を推進計画線Ｌに合わ
せてセットする（ａ）。そしてカッタヘッド４を回転駆
動させることで地山を掘削し、これに追随させて元押装
置３で推進管６を押し込む（ｂ）。先導体５により掘削
された土砂は、泥土として先導体後部の泥土取り込み口
７から取り入れ、推進管６の内方に設けた排土管（図示
せず）を通して発進立坑１まで圧送し、脱水処理等を施
した後、車両などにて搬出するようになっている。この
先導体５による掘削と推進管６の押し込みにより、推進
管一本分の長さだけ推進したなら、元押装置３の側から
新たな推進管６ａを接続する（ｃ）。この推進管６の接
続を繰り返して、先導体５が到達立坑２まで到達したな
ら、到達立坑２から先導体５を回収する（ｄ）。2. Description of the Related Art Among the underground propulsion methods of burying a propulsion pipe for extending a cable or the like in the ground, as a method capable of coping with a wide range of soil properties including collapsible ground and ground mixed with cobblestone,
A so-called excavation / discharge method is known. As shown in FIG. 14, this underground propulsion method first digs down the starting shaft 1 and the reaching shaft 2 below the level of the propulsion planning line L, then installs the main pushing device 3 in the starting shaft 1,
The leading conductor 5 provided with the cutter head 4 is set in accordance with the propulsion planning line L (a). Then, the cutter head 4 is rotationally driven to excavate the ground, and the propulsion pipe 6 is pushed by the original pushing device 3 in accordance with the excavation (b). The earth and sand excavated by the leading conductor 5 is taken in as mud from a mud intake 7 at the rear of the leading conductor, and is pumped to the starting shaft 1 through a discharging pipe (not shown) provided inside the propulsion pipe 6 to perform dehydration processing and the like. And then carry it out with a vehicle. When the excavation by the leading conductor 5 and the pushing of the propulsion pipe 6 have caused propulsion by the length of one propulsion pipe, a new propulsion pipe 6a is connected from the side of the original pushing device 3 (c). When the connection of the propulsion pipe 6 is repeated and the leading conductor 5 reaches the reaching shaft 2, the leading conductor 5 is recovered from the reaching shaft 2 (d).
【０００３】また発進立坑１は、親杭横矢板又はシート
パイルなどで土留めされており、その推進計画線Ｌの位
置には坑口８を保護するためのケーシング及びパッキン
グ（図示せず）が設けられている。パッキングには推進
管６よりも若干小さい穴が形成され、この穴が推進管６
の外周に倣うように変形して、推進管６の周囲の泥土が
発進立坑１に入ってくるのを防止するようになってい
る。The starting shaft 1 is earthed by a parent pile horizontal sheet pile or a sheet pile, and a casing and packing (not shown) for protecting the wellhead 8 are provided at the position of the propulsion planning line L. Have been. The packing is formed with a slightly smaller hole than the propulsion tube 6.
To prevent the mud around the propulsion pipe 6 from entering the starting shaft 1.
【０００４】[0004]
【発明が解決しようとする課題】ところで先導体５の外
周には、掘削土砂を泥土取り込み口７へと円滑に送るた
めの泥土通路（図示せず）が設けられ、この部分がカッ
タヘッド４による掘削外径（坑道径）よりも小さくなっ
ている。このため発進立坑１において掘削を開始すると
きは、パッキングと先導体５の凹部である泥土通路との
間に隙間ができてしまい、特に水位が高い場所を掘削す
る場合は、坑口８から作泥材や土砂、及び地下水が発進
立坑内に流出してしまう。従来はこの発進時の土砂流出
を防ぐため、先導体５の略全長に相当する長さに亘っ
て、発進立坑１の周囲に地盤改良（薬液注入等）を行っ
ていた。しかしながらこのような本工事以外の補助工事
を行うことは、工事費の増大及び工程の長期化を招くと
いう問題があった。By the way, a mud passage (not shown) for smoothly sending excavated earth and sand to the mud intake 7 is provided on the outer periphery of the leading conductor 5, and this portion is formed by the cutter head 4. It is smaller than the excavation diameter (hole diameter). For this reason, when starting excavation in the starting shaft 1, a gap is formed between the packing and the mud passage that is the concave portion of the leading conductor 5. Lumber, earth and sand, and groundwater flow into the starting shaft. Conventionally, ground improvement (chemical injection, etc.) has been performed around the start shaft 1 over a length corresponding to substantially the entire length of the leading conductor 5 in order to prevent the outflow of earth and sand during the start. However, there is a problem that performing such auxiliary works other than the main work increases the construction cost and prolongs the process.
【０００５】[0005]
【課題を解決するための手段】前記課題を解決すべく本
発明は、発進立坑の坑口より先導体を発進させて地中を
掘進すると共に、発進立坑内で、その先導体の後方に推
進管を順次接続し、かつ、坑口と推進管間をパッキング
材でシールしながら先導体を押し込む地中推進工法にお
ける先導体の発進時の坑口と先導体間をシールするため
の坑口パッキングにおいて、上記先導体の側面に形成さ
れた掘削泥土の通路となる凹部と凸部との外形に相応し
た小径部分と大径部分を形成した形状の穴を有したシー
ル部材を、上記パッキング材の後方に配置し、そのシー
ル部材を、スポンジ等の可撓性及び遮水性を有する材料
で形成し、かつ、そのシール部材の小径部分と大径部分
を、対応する先導体の凹部と凸部に密に接するように保
持部材で、上記パッキング材の後方に着脱自在に取り付
けたものである。保持部材は、シール部材の外周に接す
るカバー筒体と、そのカバー筒体の後端部に設けられた
押え板と、その押え板をパッキング材側に移動してシー
ル部材を押圧する付勢手段とからなり、その押え板とシ
ール部材間に、シール部材の穴形状と略同じ形状の穴を
有するゴムシートが設けられ、付勢手段で、上記押え板
を介してシール部材を押圧することで、上記シール部材
を径方向内方に適宜変形させてシール部材の小径部分と
大径部分を、対応する先導体の凹部と凸部に押し付ける
ようにすることが好ましい。SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides an underground by starting a leading conductor from a starting shaft of a starting shaft.
While digging, push behind the conductor in the starting shaft.
Connect pipes sequentially, and packing between wellhead and propulsion pipe
You in the ground jacking method to push the lead body while sealed with wood
To seal between the wellhead and the conductor at the start of the conductor
In wellhead packing, it is formed on the side surface of the leading body
A sealing member having a hole having a shape formed with a small diameter portion and a large diameter portion corresponding to the outer shape of the concave portion and the convex portion serving as the passage of the excavated mud, is disposed behind the packing material, and the sealing member is provided. A flexible and water-blocking material such as a sponge
And a small diameter portion and a large diameter portion of the sealing member.
Is detachably attached to the back of the packing material by a holding member so as to be in close contact with the corresponding concave and convex portions of the corresponding leading conductor .
It is a digit . The holding member contacts the outer periphery of the sealing member.
And a cover cylinder provided at the rear end of the cover cylinder.
Move the presser plate and the presser plate to the packing material side to
And a biasing means for pressing the holding member.
Between the seal member and the hole shape of the seal member.
A rubber sheet having the pressing plate
By pressing the seal member through, the seal member is appropriately deformed radially inward, and the small diameter portion of the seal member
Press the large diameter part against the concave and convex parts of the corresponding tip conductor
As you Rukoto is preferable.
【０００６】[0006]
【発明の実施の形態】以下、本発明の実施の形態を添付
図面に従って説明する。Embodiments of the present invention will be described below with reference to the accompanying drawings.
【０００７】図１乃至図３は、本発明にかかわる坑口パ
ッキングを、掘削・排土方式の地中推進工法に適用した
場合において示したものである。この坑口パッキング１
１は、先導体の外形に相応した形状の穴１２を有したシ
ール部材１３と、シール部材１３を推進計画線Ｌの所定
位置に保持するための保持部材１４とにより主として構
成されている。保持部材１４には、シール部材１３を径
方向内方に適宜変形させるための付勢手段１５が備えら
れている。FIGS. 1 to 3 show a case where a wellhead packing according to the present invention is applied to an excavation / discharge type underground propulsion method. This wellhead packing 1
Reference numeral 1 mainly includes a sealing member 13 having a hole 12 having a shape corresponding to the outer shape of the leading conductor, and a holding member 14 for holding the sealing member 13 at a predetermined position on the propulsion planning line L. The holding member 14 is provided with a biasing means 15 for appropriately deforming the seal member 13 inward in the radial direction.
【０００８】シール部材１３は、図６にも示したよう
に、所定の厚さ（例えば100mm 程度）を有したスポンジ
で成り、適度な硬さ（例えば15倍連泡）にて円板状に形
成されている。シール部材１３の材質としてはスポンジ
に限らず、適度な可撓性、遮水性などを有したものであ
ればよい。穴１２は、先導体５の断面形状に略等しい
か、或いは僅かに縮小した形状でシール部材１３の中央
に形成され、掘削孔（坑道）１６の半径よりも充分大き
い半径の円弧で成る大径部分１２ａと、掘削径よりも若
干小さい小径部分１２ｂとが、略60度ごとに交互に、三
箇所づつ設けられている。この実施の形態は、掘削径が
350mm の地中推進工法に適用するもので、例えば小径部
分１２ｂの円弧を連続させた仮想円１２ｃの径ｄ1 は29
0mm 、大径部分１２ａの仮想円１２ｅの径ｄ2 は410mm
とする。またシール部材１３の外径Ｄ1 は、例えば690m
m 程度とする。なお大径部分１２ａの一箇所には、穴１
２から外周まで半径方向に延びたスリット１７が形成さ
れている。As shown in FIG. 6, the sealing member 13 is made of a sponge having a predetermined thickness (for example, about 100 mm), and is formed in a disk shape with an appropriate hardness (for example, a 15-fold open cell). Is formed. The material of the sealing member 13 is not limited to a sponge, but may be any material having appropriate flexibility, water shielding, and the like. The hole 12 is formed at the center of the seal member 13 in a shape substantially equal to or slightly reduced in cross-sectional shape of the leading conductor 5, and has a large diameter formed by an arc having a radius sufficiently larger than the radius of the excavation hole (tunnel) 16. The portions 12a and the small-diameter portions 12b slightly smaller than the excavation diameter are provided alternately at approximately 60 degrees in three places. In this embodiment, the excavation diameter is
Intended to apply to the ground jacking method of 350 mm, for example, the diameter d 1 of the virtual circle 12c which is continuous arc of the small-diameter portion 12b is 29
0 mm, the diameter d 2 of the virtual circle 12 e of the large diameter portion 12 a is 410 mm
And The outer diameter D 1 of the seal member 13, for example, 690m
m. In one place of the large diameter portion 12a, a hole 1 is provided.
A slit 17 extending in the radial direction from 2 to the outer periphery is formed.
【０００９】このシール部材１３の押え或いは補強とし
て、ＣＲ（クロロプレン）製のゴムシート１８が設けら
れる。その厚さは例えば10mm程度の薄いものとし、比較
的硬いもの（例えば硬度90°）を使用する。ゴムシート
１８は、シール部材１３よりも僅かに小さい外径（例え
ばＤ2 ＝680mm ）の円板状を呈し、中央にシール部材１
３の穴１２と似た形状の穴１９が形成されている。その
大きさは図１に示したように、シール部材１３の穴１２
よりも一回り大きいものであり、小径部分１９ｂの仮想
円１９ｃの径ｄ3 は掘削径よりも僅かに大きく（例えば
ｄ3 ＝354mm ）、大径部分１９ａの仮想円１９ｅの径ｄ
4 はシール部材１３の大径部分１２ａの仮想円１２ｅの
径ｄ2 よりも適宜大きく（例えばｄ4 ＝470mm ）形成さ
れている。すなわちシール部材１３とゴムシート１８と
を同軸に重ね合わせた状態で、ゴムシート１８側からみ
てシール部材１３の穴１２の周囲部分が露出するように
なっている。なおゴムシート１８にもシール部材１３の
ものと同様なスリットを形成するようにしてもよい。A rubber sheet 18 made of CR (chloroprene) is provided to hold or reinforce the seal member 13. Its thickness is, for example, as thin as about 10 mm, and a relatively hard one (for example, hardness of 90 °) is used. The rubber sheet 18 has a disk shape having an outer diameter slightly smaller than that of the seal member 13 (for example, D 2 = 680 mm).
A hole 19 having a shape similar to that of the third hole 12 is formed. Its size is as shown in FIG.
The diameter d 3 of the imaginary circle 19c of the small-diameter portion 19b is slightly larger than the excavation diameter (for example, d 3 = 354 mm), and the diameter d of the imaginary circle 19e of the large-diameter portion 19a is larger.
4 is formed to be appropriately larger (for example, d 4 = 470 mm) than the diameter d 2 of the virtual circle 12e of the large diameter portion 12a of the seal member 13. That is, in a state where the seal member 13 and the rubber sheet 18 are coaxially overlapped, the peripheral portion of the hole 12 of the seal member 13 is exposed when viewed from the rubber sheet 18 side. Note that a slit similar to that of the seal member 13 may be formed in the rubber sheet 18.
【００１０】次に保持部材１４は、シール部材１３及び
ゴムシート１８の外周に被さる大きさの短円柱状のカバ
ー筒体２０と、カバー筒体２０の内径側に設けられる円
環状の押え板２１とで成る。この実施の形態では、カバ
ー筒体２０が坑口のエントランスボックス２２に取り付
けられることで、全体がエントランスボックス２２に着
脱自在に保持されるようになっている。エントランスボ
ックス２２は、図８にも示したように正面視で略正方形
の外形を有したフレーム板で成り、その前面２２ａに掘
削径よりも充分大きい径の穴２３が形成されている。そ
して後端側２２ｂが、発進立坑１の周壁１ａに設けられ
た図示しない土留め材（矢板、Ｈ鋼、シートパイル等）
に支持されて、推進計画線Ｌの坑口位置に保持されてい
る。ボックス前面２２ａにはその穴２３と同径の穴を有
した取付板２４が備えられ、穴２３の外周に配置された
多数（図示例では12個）のボルト２５及びワッシャー２
６によって、パッキング材２７が取り付けられている。
パッキング材２７の中央には掘削径よりも僅かに小さい
径の穴２８が形成され、推進管６が挿通されると、図２
中二点鎖線にて示したように、穴２８の縁部２８ａが捲
れるように変形して，その周囲をシールするようになっ
ている。Next, the holding member 14 includes a short cylindrical cover cylinder 20 having a size to cover the outer periphery of the seal member 13 and the rubber sheet 18, and an annular pressing plate 21 provided on the inner diameter side of the cover cylinder 20. And In this embodiment, the cover cylinder 20 is attached to the entrance box 22 at the wellhead so that the entire body is detachably held by the entrance box 22. As shown in FIG. 8, the entrance box 22 is formed of a frame plate having a substantially square outer shape when viewed from the front, and a hole 23 having a diameter sufficiently larger than the excavation diameter is formed on the front surface 22a. And the rear end side 22b is an unillustrated earth retaining material (sheet pile, H steel, sheet pile, etc.) provided on the peripheral wall 1a of the starting shaft 1.
And held at the wellhead position of the propulsion planning line L. The box front surface 22a is provided with a mounting plate 24 having a hole having the same diameter as the hole 23, and a large number (12 in the illustrated example) of bolts 25 and washers 2 arranged around the hole 23.
6, a packing material 27 is attached.
In the center of the packing material 27, a hole 28 having a diameter slightly smaller than the excavation diameter is formed, and when the propulsion pipe 6 is inserted, FIG.
As shown by the two-dot chain line, the edge 28a of the hole 28 is deformed so as to be turned up, and the periphery thereof is sealed.
【００１１】カバー筒体２０は、図４にも示すように、
縦に半割りされた構造の鋼板で成り、その分割端に形成
されたフランジ２９同士がボルト・ナット３０にて接合
されるようになっている。カバー筒体２０の一方の軸端
内周には、取付用の穴３１を有したブラケット３２が設
けられ、エントランスボックス２２のパッキング取付穴
を利用して、カバー筒体２０が共締めにてパッキング材
２７及び取付板２４に重ね合わされるようになっている
（図８参照）。この実施の形態では、ブラケット３２は
周方向に等間隔で六個設けられ、12個のパッキング取付
穴を一つ置きに利用して固定するようになっている。押
え板２１は、外径Ｄ3 がカバー筒体２０の内径ｄ5 より
も僅かに小さく（例えばＤ3 ＝680mm ＜ｄ5 ＝690mm
）、内径ｄ6 はゴムシート１８の大径部分仮想円１９
ａの径ｄ4 よりも充分大きいものとなっている（例えば
ｄ6 ＝530mm ＞ｄ4 ＝470mm ）。As shown in FIG. 4, the cover cylinder 20 is
It is made of a steel plate having a vertically divided structure, and flanges 29 formed at the divided ends thereof are joined by bolts and nuts 30. A bracket 32 having a mounting hole 31 is provided on the inner periphery of one shaft end of the cover cylinder 20, and the cover cylinder 20 is packed together by using the packing mounting hole of the entrance box 22. It is configured to be superimposed on the material 27 and the mounting plate 24 (see FIG. 8). In this embodiment, six brackets 32 are provided at equal intervals in the circumferential direction, and are fixed by using every other twelve packing mounting holes. The outer diameter D 3 of the presser plate 21 is slightly smaller than the inner diameter d 5 of the cover cylinder 20 (for example, D 3 = 680 mm <d 5 = 690 mm).
), The inner diameter d 6 is a large diameter virtual circle 19 of the rubber sheet 18.
It has assumed sufficiently larger than the diameter d 4 of a (e.g. d 6 = 530mm> d 4 = 470mm).
【００１２】そしてカバー筒体２０の外周には、軸方向
に延びたボルトロッド３３が溶接等にて取り付けられ、
これに相応する位置で押え板２１の外周には、ボルト挿
通穴３４を有したブラケット板３５が取り付けられてい
る。この実施の形態では、これらボルトロッド３３及び
ブラケット板３５が周方向に等間隔に、八個づつ設けら
れている。ボルトロッド３３は、基端がカバー筒体２０
の軸方向後端に揃えられ、先端がカバー筒体２０の軸方
向前端から所定の長さだけ突出している。ブラケット板
３５は、ボルトロッド３３の突出した長さに相応する高
さ（例えば50mm程度）の断面Ｌ字状を呈し、押え板２１
の径方向外方に張り出している。すなわちこれらボルト
ロッド３３及びブラケット板３５によって付勢手段１５
が構成されており、ボルトロッド３３の先端をボルト挿
通穴３４に通してナット３６でブラケット板３５に締め
付けることで、押え板２１を介してシール部材１３及び
ゴムシート１８をカバー筒体２０内に収容保持すると共
に、その締付力でシール部材１３の穴１２の周囲部分を
径方向内方に膨出するように変形させて、先導体５の外
周面に押し付けるようになっている。A bolt rod 33 extending in the axial direction is attached to the outer periphery of the cover cylinder 20 by welding or the like.
At a position corresponding to this, a bracket plate 35 having a bolt insertion hole 34 is attached to the outer periphery of the holding plate 21. In this embodiment, eight bolt rods 33 and eight bracket plates 35 are provided at equal intervals in the circumferential direction. The bolt rod 33 has a base end covered with the cover cylinder 20.
And the front end projects from the front end in the axial direction of the cover cylinder 20 by a predetermined length. The bracket plate 35 has an L-shaped cross section with a height (for example, about 50 mm) corresponding to the length of the bolt rod 33 protruding.
Projecting outward in the radial direction. That is, the urging means 15 is formed by the bolt rod 33 and the bracket plate 35.
The seal member 13 and the rubber sheet 18 are inserted into the cover cylinder 20 via the holding plate 21 by passing the tip of the bolt rod 33 through the bolt insertion hole 34 and tightening the nut 36 to the bracket plate 35. In addition to holding and holding, the peripheral portion of the hole 12 of the seal member 13 is deformed so as to expand radially inward by the tightening force, and pressed against the outer peripheral surface of the leading conductor 5.
【００１３】このように構成された坑口パッキング１１
を使用して地中推進工法を実施するに際しては、推進計
画線Ｌのレベル以下に発進立坑１を掘り下げ、その周壁
１ａを親杭横矢板又はシートパイルなどで土留めする。
そして発進立坑１の縦推進計画線Ｌの位置にエントラン
スボックス２２を取り付けて、実質的な坑口８を設置す
る。そして図８に示したように、まずカバー筒体２０を
ボルト３７及びワッシャー３８にて、エントランスボッ
クス２２の前面２２ａに取り付ける。次にカバー筒体２
０内にシール部材１３を嵌め込み、さらにその前面にゴ
ムシート１８を重ね合わせる。このとき穴１２，１９の
大径部分１２ａ，１９ａ及び小径部分１２ｂ，１９ｂ
を、掘削姿勢の先導体８の外周形状に一致するように、
例えば大径部分１２ａ，１９ａの一つが上端に位置する
ようにセットする。そしてゴムシート１８の上に押え板
２１を、ブラケット板３５のボルト挿通穴３４にボルト
ロッド３３に挿通させつつ重ね合わせ、ナット３６にて
固定する。そしてブラケット板３５の立ち上がりの高さ
（締め代）を利用して、ナット３６をさらに締め付ける
ことで、押え板２１を押し込んで、シール部材１３を軸
方向に適宜圧縮させる。シール部材１３は軸方向両面が
拘束されているので、フリーとなっている中央の部分
が、穴１２が縮径するように変形する。The wellhead packing 11 constructed as described above
When the underground propulsion method is carried out using the method, the starting shaft 1 is dug down below the level of the propulsion planning line L, and its peripheral wall 1a is earthed with a parent pile horizontal sheet pile or sheet pile.
Then, the entrance box 22 is attached at the position of the vertical propulsion planning line L of the starting shaft 1, and a substantial wellhead 8 is installed. Then, as shown in FIG. 8, first, the cover cylinder 20 is attached to the front surface 22 a of the entrance box 22 with the bolt 37 and the washer 38. Next, cover cylinder 2
The seal member 13 is fitted into the inside of the rubber sheet 0, and the rubber sheet 18 is further superimposed on the front surface thereof. At this time, the large diameter portions 12a, 19a and the small diameter portions 12b, 19b of the holes 12, 19 are formed.
To match the outer peripheral shape of the leading conductor 8 in the excavation posture,
For example, it is set so that one of the large diameter portions 12a and 19a is located at the upper end. Then, the holding plate 21 is superimposed on the rubber sheet 18 while being inserted into the bolt insertion hole 34 of the bracket plate 35 with the bolt rod 33, and is fixed with the nut 36. The nut 36 is further tightened by using the rising height (tightening allowance) of the bracket plate 35, whereby the pressing plate 21 is pushed in, and the seal member 13 is appropriately compressed in the axial direction. Since both sides in the axial direction of the seal member 13 are constrained, the free center portion is deformed so that the hole 12 is reduced in diameter.
【００１４】これで図９に示すように、カッタヘッドを
備えた先導体５が坑口８から土中へと発進する際に、そ
の泥土通路である凹部５ａと、推進管６の外径に略等し
い外径の凸部５ｂとに、それぞれシール部材１３の小径
部分１２ｂと大径部分１２ａとが密着し、先導体５の前
進を妨げることなく追随変形しつつ、先導体５の周囲か
ら土砂や地下水が発進立坑１内に入ってくるのを阻む。
先導体５のカッタヘッドは、土中に適宜押し込まれた
後、回転駆動して地山を掘削し、これに追随して元押装
置により推進管６が押し込まれる。先導体５の全体が土
中に入ったなら、坑口８においては推進管６の周囲のシ
ールを行えばよいので、坑口パッキング１１は取り外し
て、エントランスボックス２２のみの設置に切り換える
ようにしてよい。この取り外しは、まずナット３６を弛
めて、押え板２１、ゴムシート１８及びシール部材１３
をカバー筒体２０から取り出す。シール部材１３はスリ
ット１７を広げることで簡単に外すことができる。そし
て取付ボルト３７を弛めてエントランスボックス２２か
らカバー筒体２０を離脱させる。カバー筒体２０は半割
り構造なので、フランジ２９のボルト・ナット３０の回
動操作で簡単に外すことができる。As shown in FIG. 9, when the leading conductor 5 having the cutter head starts moving from the wellhead 8 into the soil, the outer diameter of the recess 5a, which is a mud passage, and the outer diameter of the propulsion pipe 6 are substantially equal to each other. to the convex portion 5b of the outer diameter equal to, respectively and the small diameter portion 12 b of the seal member 13 and the large diameter portion 12 a is in close contact, while follow deformation without interfering with the advancement of the lead body 5, from the periphery of the leading body 5 Prevents sediment and groundwater from entering the starting shaft 1.
After the cutter head of the leading conductor 5 is appropriately pushed into the soil, it is rotationally driven to excavate the ground, and the propulsion pipe 6 is pushed by the original pushing device following this. When the entirety of the leading conductor 5 has entered the ground, the well 8 may be sealed around the propulsion pipe 6. Therefore, the wellhead packing 11 may be removed, and the installation may be switched to only the entrance box 22. For this removal, first, the nut 36 is loosened, and the holding plate 21, the rubber sheet 18 and the sealing member 13 are removed.
From the cover cylinder 20. The seal member 13 can be easily removed by widening the slit 17. Then, the cover cylinder 20 is detached from the entrance box 22 by loosening the mounting bolt 37. Since the cover cylinder 20 has a half-split structure, it can be easily removed by rotating the bolt / nut 30 of the flange 29.
【００１５】以降推進機は、図１４に示したように、掘
削土砂を先導体後部の泥土取り込み口７から発進立坑１
まで圧送しつつ掘進を行い、元押装置３による推進管６
の押し込みを行うことで、新たな推進管６ｎを接続し、
先導体５が到達立坑２まで到達したなら、到達立坑２よ
り先導体５を回収する。Thereafter, as shown in FIG. 14, the propulsion machine starts the excavated earth 1
Excavation while pumping up to
To connect a new propulsion pipe 6n,
When the leading conductor 5 reaches the reaching shaft 2, the leading conductor 5 is recovered from the reaching shaft 2.
【００１６】このように、シール部材１３に先導体５の
凹凸形状（５ａ，５ｂ）に相応した穴１２を形成し、カ
バー筒体２０及び押え板２１によってエントランスボッ
クス２２に着脱自在に支持させたので、発進時における
先導体５の周囲からの土砂等の流入を防ぐことができ
る。すなわち発進立坑１の付近の薬液注入などによる地
盤改良範囲を大幅に縮小することができ、工費削減及び
工期短縮が達成される。またカバー筒体２０及び押え板
２１に、シール部材１３をナット締めにより適宜変形さ
せて先導体５の周面に押し付けるボルトロッド３３及び
ブラケット板３５を設けたので、シール部材１３の穴１
２の周囲のみを可撓性が高いフリーな状態とし、ゴムシ
ート１８及び押え板２１により、外周側に向かって段階
的に強度が高くなる構造とすることができ、先導体５が
掘削前進する際の摩擦力にも充分に耐える有効なシール
力を発揮することができる。そしてこの実施の形態の保
持部材１４は、既存のエントランスボックス２２に簡単
に取り付けることができるので、極めて汎用性に富むと
共に、繰り返し使用することができ、シール部材１３の
交換も容易にできる。As described above, the seal member 13 is formed with the holes 12 corresponding to the concavo-convex shape (5a, 5b) of the leading conductor 5, and is detachably supported on the entrance box 22 by the cover cylinder 20 and the holding plate 21. Therefore, it is possible to prevent inflow of earth and sand from around the leading conductor 5 at the time of starting. That is, it is possible to greatly reduce the ground improvement range by injecting a chemical solution or the like near the starting shaft 1, thereby achieving a reduction in construction cost and construction period. Further, since the cover rod 20 and the holding plate 21 are provided with the bolt rod 33 and the bracket plate 35 for appropriately deforming the sealing member 13 by tightening the nut and pressing the sealing member 13 against the peripheral surface of the leading conductor 5, the hole 1 of the sealing member 13 is provided.
Only the periphery of 2 is in a free state with high flexibility, and the rubber sheet 18 and the pressing plate 21 can be structured so that the strength gradually increases toward the outer peripheral side, and the leading conductor 5 excavates and advances. An effective sealing force that can sufficiently withstand the frictional force at the time can be exhibited. Since the holding member 14 of this embodiment can be easily attached to the existing entrance box 22, it is extremely versatile, can be used repeatedly, and the seal member 13 can be easily replaced.
【００１７】次に図１０乃至図１３は、掘削径が前記実
施の形態よりも大きい500mm のものに適用する坑口パッ
キングを示したもので、シール部材４１及びゴムシート
４２の穴４３，４４は、大口径先導体（図示せず）の外
周形状に合わせて、大径部分４３ａ，４４ａ及び小径部
分４３ｂ，４３ｂがそれぞれ四箇所、45度毎に交互に配
置された形状となっている。シール部材４１のサイズの
一例としては、外径Ｄ4 が880mm 、小径部分４３ｂの仮
想円４３ｃの径ｄ7 は400mm 、大径部分４３ａの仮想円
４３ｅの径ｄ8 は535mm とする。またゴムシート４２の
サイズの一例としては、外径Ｄ5 が870mm 、小径部分４
４ｂの仮想円４４ｃの径ｄ9 は480mm 、大径部分４４ａ
の仮想円ｄ10の径は605mm とする。また保持部材となる
カバー筒体４５の内径ｄ11は例えば880mm とし、押え板
４６の外径Ｄ6 及び内径ｄ12はそれぞれ例えばＤ6 ＝87
0mm 、ｄ12＝720mm とする。また押え板４６は二分割の
構造となっており、その分割端に設けられたフランジ板
４７にて軸方向に拘束されるようになっている。すなわ
ち押え板４６の着脱を容易に行うことができる。なおこ
の構造を前記実施の形態の押え板２１に適用してもよい
（図３の符号４７参照）。なお図１０では省略したが、
図４のカバー筒体２０と同様に半割り構造のカバー筒体
４５として、着脱が容易な構造としてもよい。この他の
構成及び作用効果は前記実施の形態と同様であるので、
図中対応する構成に同一の符号を付し、説明を省略す
る。Next, FIG. 10 to FIG. 13 show a wellhead packing applicable to a drilling diameter of 500 mm larger than that of the above-described embodiment, wherein the holes 43 and 44 of the seal member 41 and the rubber sheet 42 are The large-diameter portions 43a, 44a and the small-diameter portions 43b, 43b are arranged alternately at four locations, each 45 degrees, according to the outer peripheral shape of the large-diameter leading conductor (not shown). An example of the size of the seal member 41, the outer diameter D 4 is 880 mm, the diameter d 7 of the virtual circle 43c of the small diameter portion 43b is 400 mm, the diameter d 8 of the virtual circle 43e of the large diameter portion 43a is set to 535 mm. As an example of the size of the rubber sheet 42 is also the outer diameter D 5 is 870 mm, smaller diameter portion 4
The diameter d 9 of the virtual circle 44c of 4b is 480 mm, and the large diameter portion 44a
The diameter of the virtual circle d 10 is the 605mm of. The inner diameter d 11 of the cover cylinder 45 of the holding member is, for example, 880 mm, an outer diameter D 6 and the inner diameter d 12 are each for example D 6 = 87 of the pressing plate 46
0 mm and d 12 = 720 mm. The pressing plate 46 has a two-part structure, and is restrained in the axial direction by a flange plate 47 provided at the divided end. That is, the holding plate 46 can be easily attached and detached. Note that this structure may be applied to the holding plate 21 of the embodiment (see reference numeral 47 in FIG. 3). Although omitted in FIG. 10,
Similar to the cover cylinder 20 of FIG. 4, the cover cylinder 45 having a half-split structure may be configured to be easily detachable. Since the other configuration and operation and effect are the same as those of the above-described embodiment,
Corresponding components in the drawings are denoted by the same reference numerals, and description thereof will be omitted.
【００１８】なお以上の実施の形態では、坑口パッキン
グ１１をエントランスボックス２２に着脱させる構成と
したが、エントランスボックス２２を省略して坑口８に
直接設け、先導体５に引き続き推進管６に対するシール
を行うように構成することもできる。またシール部材及
び保持部材の構成は、前記実施の形態で例示した形状に
限るものではなく、そのサイズも先導体の形状に相応さ
せて、それぞれの機能を発揮できるように設計すべきも
のである。さらにこの実施の形態では坑口パッキングを
発進立坑に設けるものとしたが、同様の事情となる到達
立坑の推進計画線の位置に設けても構わない。すなわち
到達時の到達立坑への土砂流出を防止することができ
る。In the above-described embodiment, the wellhead packing 11 is attached to and detached from the entrance box 22. However, the entrance box 22 is omitted and provided directly on the wellhead 8, and the seal for the propulsion pipe 6 is provided after the leading conductor 5. It can also be configured to do so. The configurations of the sealing member and the holding member are not limited to the shapes exemplified in the above-described embodiment, and the sizes thereof should be designed so as to correspond to the shape of the leading conductor so that the respective functions can be exhibited. Further, in this embodiment, the wellhead packing is provided in the starting shaft, but may be provided in the position of the promotion plan line of the reaching shaft in the same situation. That is, it is possible to prevent the outflow of earth and sand into the arrival shaft at the time of arrival.
【００１９】[0019]
【発明の効果】以上要するに本発明によれば、先導体の
外周形状に凹凸があることに起因する発進時の土砂等の
流出を防ぐことができ、薬液注入などの地盤改良範囲を
大幅に縮小できて、工費削減及び工期短縮が達成され
る。また保持部材の付勢手段により、押え板を介してシ
ール部材を押圧することで、シール部材の穴の周囲のみ
が可撓性の高いフリーな状態となると共に、外周側に向
かって段階的に強度が高くなり、先導体の掘削前進の際
の摩擦力に耐えるシール力を発揮することができる。In summary, according to the present invention, it is possible to prevent the outflow of earth and sand at the time of starting due to irregularities in the outer peripheral shape of the leading conductor, and to greatly reduce the ground improvement area such as injection of a chemical solution. As a result, construction cost and construction period can be reduced. In addition , the urging means of the holding member is used to
By pressing the sealing member, only around the hole of the sealing member
Becomes free and highly flexible, and
Thus, the strength gradually increases, and a sealing force that can withstand a frictional force when the leading conductor is excavated and advanced can be exhibited.
【図１】本発明にかかわる坑口パッキングの実施の形態
を示した正面図である。FIG. 1 is a front view showing an embodiment of wellhead packing according to the present invention.
【図２】図１のＡ−Ａ線矢視断面図である。FIG. 2 is a sectional view taken along line AA of FIG.
【図３】図１の斜視図である。FIG. 3 is a perspective view of FIG. 1;
【図４】図１のカバー筒体を示した図であり、（ａ）は
側断面図、（ｂ）は正面図である。4A and 4B are diagrams showing the cover cylinder of FIG. 1, wherein FIG. 4A is a side sectional view and FIG. 4B is a front view.
【図５】図１の押え板を示した図であり、（ａ）は側断
面図、（ｂ）は正面図である。5A and 5B are views showing the holding plate of FIG. 1, wherein FIG. 5A is a side sectional view and FIG. 5B is a front view.
【図６】図１のシール部材を示した正面図である。FIG. 6 is a front view showing the seal member of FIG. 1;
【図７】図１のゴムシートを示した正面図である。FIG. 7 is a front view showing the rubber sheet of FIG. 1;
【図８】図４のカバー筒体の取付状況を示した斜視図で
ある。FIG. 8 is a perspective view showing the state of attachment of the cover cylinder of FIG. 4;
【図９】図１の坑口パッキングの使用状況を示した斜視
図である。FIG. 9 is a perspective view showing a use state of the wellhead packing of FIG. 1;
【図１０】本発明の他の実施の形態であるカバー筒体を
示した図であり、（ａ）は側断面図、（ｂ）は正面図で
ある。FIGS. 10A and 10B are diagrams showing a cover cylinder body according to another embodiment of the present invention, wherein FIG. 10A is a side sectional view and FIG. 10B is a front view.
【図１１】本発明の他の実施の形態である押え板を示し
た図であり、（ａ）は側断面図、（ｂ）は正面図であ
る。11A and 11B are diagrams showing a holding plate according to another embodiment of the present invention, wherein FIG. 11A is a side sectional view and FIG. 11B is a front view.
【図１２】本発明の他の実施の形態であるシール部材を
示した正面図である。FIG. 12 is a front view showing a seal member according to another embodiment of the present invention.
【図１３】本発明の他の実施の形態であるゴムシートを
示した正面図である。FIG. 13 is a front view showing a rubber sheet according to another embodiment of the present invention.
【図１４】本発明を適用する地中推進工法を示した側断
面図である。FIG. 14 is a side sectional view showing an underground propulsion method to which the present invention is applied.
１ 発進立坑 ２ 到達立坑 ５ 先導体 ５ａ 凹部 ５ｂ 凸部 ６ 推進管 ８ 坑口 １１ 坑口パッキング １２ 穴 １３，４１ シール部材 １４ 保持部材 １５ 付勢手段 １６ 掘削孔（坑道） １８，４２ ゴムシート ２０，４５ カバー筒体 ２１，４６ 押え板 Ｌ 推進計画線 Reference Signs List 1 starting shaft 2 reaching shaft 5 leading conductor 5a concave portion 5b convex portion 6 propulsion tube 8 wellhead 11 wellhead packing 12 hole 13,41 sealing member 14 holding member 15 urging means 16 drilling hole (tunnel) 18,42 rubber sheet 20,45 Cover cylinder 21, 46 Holding plate L Propulsion plan line
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.7，ＤＢ名) E21D 9/06 311 ──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. 7 , DB name) E21D 9/06 311
Claims (2)
地中を掘進すると共に、発進立坑内で、その先導体の後
方に推進管を順次接続し、かつ、坑口と推進管間をパッ
キング材でシールしながら先導体を押し込む地中推進工
法における先導体の発進時の坑口と先導体間をシールす
るための坑口パッキングにおいて、上記先導体の側面に
形成された掘削泥土の通路となる凹部と凸部との外形に
相応した小径部分と大径部分を形成した形状の穴を有し
たシール部材を、上記パッキング材の後方に配置し、そ
のシール部材を、スポンジ等の可撓性及び遮水性を有す
る材料で形成し、かつ、そのシール部材の小径部分と大
径部分を、対応する先導体の凹部と凸部に密に接するよ
うに保持部材で、上記パッキング材の後方に着脱自在に
取り付けたことを特徴とする坑口パッキング。1. A starting conductor is started from a wellhead of a starting shaft.
While excavating underground, in the starting shaft, after the conductor ahead
Connecting the propulsion pipe to the
To seal the gap between the leading body and the start-time of the wellhead of the leading body of definitive underground jacking method to push the lead body while sealed with King material
In wellhead packing order, to the side of the leading body
A seal member having a hole having a shape having a small diameter portion and a large diameter portion corresponding to the outer shape of the concave portion and the convex portion serving as a passage of the formed excavated mud is arranged behind the packing material.
The seal member is made of a material such as sponge,
Formed of a material having a small diameter and a large diameter
Make the diameter part closely contact the concave and convex parts of the corresponding tip conductor.
The holding member makes it detachable behind the packing material.
Wellhead packing characterized by being attached .
するカバー筒体と、そのカバー筒体の後端部に設けられ
た押え板と、その押え板をパッキング材側に移動してシ
ール部材を押圧する付勢手段とからなり、その押え板と
シール部材間に、シール部材の穴形状と略同じ形状の穴
を有するゴムシートが設けられ、付勢手段で、上記押え
板を介してシール部材を押圧することで、上記シール部
材を径方向内方に適宜変形させてシール部材の小径部分
と大径部分を、対応する先導体の凹部と凸部に押し付け
るようにした請求項１記載の坑口パッキング。The holding member is in contact with an outer periphery of a sealing member.
And a cover cylinder provided at a rear end of the cover cylinder.
Move the holding plate and the holding plate to the packing material
And a biasing means for pressing the holding member.
Between the seal members, holes with the same shape as the hole shape of the seal member
A rubber sheet having
By pressing the seal member through a plate, the seal member is appropriately deformed radially inward, and the small-diameter portion of the seal member is deformed.
And a large diameter portion, corresponding lead body recess and wellhead packing according to claim 1, wherein you pressed so <br/> Ru the convex portion of the.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP08286940A JP3138646B2 (en) | 1996-10-29 | 1996-10-29 | Wellhead packing |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP08286940A JP3138646B2 (en) | 1996-10-29 | 1996-10-29 | Wellhead packing |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH10131672A JPH10131672A (en) | 1998-05-19 |
| JP3138646B2 true JP3138646B2 (en) | 2001-02-26 |
Family
ID=17710929
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP08286940A Expired - Fee Related JP3138646B2 (en) | 1996-10-29 | 1996-10-29 | Wellhead packing |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3138646B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003003785A (en) * | 2001-06-26 | 2003-01-08 | Ashimori Ind Co Ltd | Sealing bag |
| JP2012097421A (en) * | 2010-10-29 | 2012-05-24 | Daiei Kensetsu Kk | Water cut-off device |
-
1996
- 1996-10-29 JP JP08286940A patent/JP3138646B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH10131672A (en) | 1998-05-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3138646B2 (en) | Wellhead packing | |
| JP2003214085A (en) | Mouth forming method on arrival of shield machine and shield machine | |
| JP3177468B2 (en) | Standing block, standing excavation method and sewer propulsion method | |
| JP2507827B2 (en) | Underground method of pipe | |
| JP2681741B2 (en) | Vertical shaft construction method and composite soil retaining material used for it | |
| JP3831370B2 (en) | Construction method of foundation pile at the site of waste disposal site | |
| JP4153636B2 (en) | Vertical tunnel wellhead stop device | |
| JP3182099B2 (en) | Removal method of shield excavator from arrival port | |
| JP3616898B2 (en) | Method for joining underground structures using propulsion device | |
| JP4323075B2 (en) | Shaft opening structure | |
| JP3172432B2 (en) | Starting a shield machine from a shaft | |
| JPH02140396A (en) | Annular excavating device | |
| JP4499931B2 (en) | Shield excavator and shield excavation method | |
| JPH0512392Y2 (en) | ||
| JP3488277B2 (en) | Duplex steel pipe underground joining method | |
| JPH0426557Y2 (en) | ||
| JP3520358B2 (en) | Connection structure between horizontal shaft structure and vertical shaft structure | |
| JPH05156635A (en) | Open shield construction method and concrete caisson used therefor | |
| JP2004044265A (en) | Entrance structure | |
| JP2009052238A (en) | Entrance sealing apparatus | |
| JP2002276288A (en) | Starting structure for excavator | |
| JP3026303U (en) | Packing metal fittings | |
| JP2777267B2 (en) | Underground tunnel joining method and shaft shaft used for the method | |
| JPH01121423A (en) | Method of burying branch pipe | |
| JP4142828B2 (en) | Shield machine |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| S531 | Written request for registration of change of domicile |
Free format text: JAPANESE INTERMEDIATE CODE: R313531 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20091208 Year of fee payment: 9 |
|
| LAPS | Cancellation because of no payment of annual fees |