JP2023016904A - Ground reinforcement steel pipe - Google Patents

Ground reinforcement steel pipe Download PDF

Info

Publication number
JP2023016904A
JP2023016904A JP2022189311A JP2022189311A JP2023016904A JP 2023016904 A JP2023016904 A JP 2023016904A JP 2022189311 A JP2022189311 A JP 2022189311A JP 2022189311 A JP2022189311 A JP 2022189311A JP 2023016904 A JP2023016904 A JP 2023016904A
Authority
JP
Japan
Prior art keywords
pipe
steel pipe
steel
ground reinforcement
main body
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.)
Granted
Application number
JP2022189311A
Other languages
Japanese (ja)
Other versions
JP7366381B2 (en
Inventor
一聡 坂根
Kazutoshi Sakane
昌和 香山
Masakazu Kayama
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fuji Kogyo KK
Fujimori Sangyo Co Ltd
Original Assignee
Fuji Kogyo KK
Fujimori Sangyo Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Fuji Kogyo KK, Fujimori Sangyo Co Ltd filed Critical Fuji Kogyo KK
Priority to JP2022189311A priority Critical patent/JP7366381B2/en
Publication of JP2023016904A publication Critical patent/JP2023016904A/en
Application granted granted Critical
Publication of JP7366381B2 publication Critical patent/JP7366381B2/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Landscapes

  • Excavating Of Shafts Or Tunnels (AREA)
  • Non-Disconnectible Joints And Screw-Threaded Joints (AREA)

Abstract

PROBLEM TO BE SOLVED: To improve workability by reducing the weight of a ground reinforcement steel pipe that is sequentially spliced by screw joints while ensuring required strength.
SOLUTION: Short connecting pipe portions 20, 30 having threaded portions 24, 34 are inseparably joined to an end portion of a pipe body 11 having no threaded portion in a steel pipe 10 for ground reinforcement. The thickness of the pipe body 11 is smaller than the thickness of straight portions 22, 32 of the connecting pipe portions 20, 30. The connecting pipe portions 20, 30 are made of general structural carbon steel pipes, and the pipe body 11 is made of a steel pipe having a higher tensile strength than the general structural carbon steel pipes.
SELECTED DRAWING: Figure 2
COPYRIGHT: (C)2023,JPO&INPIT

Description

本発明は、例えばＮＡＴＭ（New Austrian Tunneling Method）工法によるトンネル施工の際の補助工法として地山に打ち込まれる地山補強鋼管に関し、特に、ネジ接合によって順次継ぎ足されて長尺化される先受け鋼管などに適した地山補強用鋼管に関する。 The present invention relates to a rock reinforcement steel pipe that is driven into the ground as a supplementary method for tunnel construction by, for example, the NATM (New Austrian Tunneling Method) method, and in particular, a pre-received steel pipe that is sequentially spliced by screw joints to lengthen it. The present invention relates to a steel pipe for ground reinforcement suitable for such as.

トンネル補助工法の１つであるＡＧＦ（All Ground Fasten）工法においては、長さ３ｍ程度の鋼管を４本程度、順次継ぎ足しながら、切羽前方の地山に打ち込み、地山を先受け補強する。各鋼管の一端部には雄ネジが形成され、他端部には雌ネジが形成されている。先行して打ち込んだ鋼管と後続の鋼管とをネジ接合することで一直線に継ぎ足す。最先端の鋼管及び最後尾の鋼管においては片方の端部だけに雄ネジ又は雌ネジが形成されていればよい。 In the AGF (All Ground Fasten) method, which is one of the tunnel auxiliary construction methods, about four steel pipes with a length of about 3 m are sequentially spliced and driven into the natural ground in front of the face to reinforce the natural ground. A male thread is formed at one end of each steel pipe, and a female thread is formed at the other end. The preceding steel pipe and the succeeding steel pipe are screwed together to join in a straight line. The steel pipe at the forefront and the steel pipe at the rear only need to be formed with a male thread or a female thread at only one end.

通常、この種の地山補強用の各鋼管は、一体物の単体管であり、全体が単一の鋼材質によって構成されている。具体的には、一般構造用炭素鋼鋼管ＳＴＫ４００（ＪＩＳ Ｇ３４４４）を用いるのが一般的である。 Usually, each steel pipe for ground reinforcement of this type is an integral single pipe, and is entirely made of a single steel material. Specifically, a general structural carbon steel pipe STK400 (JIS G3444) is generally used.

特許文献１における地山補強用鋼管は、管本体と、それとは別体の接続管部とを有している。管本体は、地山補強に必要な強度を発現するための所要の肉厚を有している。管本体の一端部の内周面には雌ネジが形成されている。管本体の他端部に接続管部が摩擦圧接によって接合されている。接続管部は、管本体よりも厚肉かつ短い管によって構成され、その外周面に雄ネジが形成されている。
特許文献２の地山補強用鋼管においては、管本体の一端部に雄ネジ付きの接続管部が接合され、他端部に雌ネジ付きの接続管部が接合されている。管本体には雄ネジも雌ネジも形成されていない。 The steel pipe for ground reinforcement in Patent Document 1 has a pipe main body and a connecting pipe portion which is separate therefrom. The pipe body has a required wall thickness for exhibiting the strength required for ground reinforcement. A female thread is formed on the inner peripheral surface of one end of the pipe body. A connection pipe portion is joined to the other end portion of the pipe body by friction welding. The connection pipe portion is configured by a pipe that is thicker and shorter than the pipe main body, and has a male thread formed on its outer peripheral surface.
In the steel pipe for ground reinforcement of Patent Document 2, a connecting pipe portion with a male thread is joined to one end of a pipe body, and a connecting pipe portion with a female thread is joined to the other end. Neither male nor female threads are formed on the pipe body.

特開２０１６－０５３２６８号公報JP 2016-053268 A 実用新案登録第３１８２６６３号公報（請求項２、図２）Utility Model Registration No. 3182663 (Claim 2, Figure 2)

一般的なＡＧＦ工法用の鋼管の標準スペックは、肉厚６ｍｍ程度、外直径１１４．３ｍｍ程度、長さ３ｍ程度であり、重量は約５０ｋｇである。このため、人力で持ち運ぶのは容易でなく作業性が良好でない。
特許文献１の地山補強用鋼管においては、管本体の肉厚を、地山補強に必要な強度を確保可能、かつ一端部の内周面に雌ネジを形成可能な大きさにする必要がある。特許文献１には、管本体の肉厚を２．５ｍｍ～７ｍｍ程度とするとの記載があるが、所要のネジ接合強度を得るためのネジ山高さを考えると、管本体の肉厚は実際には４．５ｍｍ程度以上は必要と考えられる。このため、あまり軽量化できない。
特許文献２の地山補強用鋼管においては、管本体を、ネジ山を形成し得る肉厚にする必要はないが、一般構造用炭素鋼鋼管を用いる限り、地山補強に必要なある程度の肉厚を有していなければならず、作業性を十分改善し得るまで軽量化することは期待できない。
本発明は、かかる事情に鑑み、ネジ接合によって順次継ぎ足される地山補強用鋼管を、所要強度を確保しつつ軽量化して、作業性を改善することを目的とする。 The standard specifications of a steel pipe for general AGF construction method are about 6 mm in wall thickness, about 114.3 mm in outer diameter, about 3 m in length, and about 50 kg in weight. For this reason, it is not easy to carry manually and workability is not good.
In the steel pipe for ground reinforcement of Patent Document 1, the wall thickness of the pipe body must be set to a size that can ensure the strength necessary for ground reinforcement and that a female screw can be formed on the inner peripheral surface of one end. be. Patent Document 1 states that the thickness of the pipe body is about 2.5 mm to 7 mm. is considered necessary to be about 4.5 mm or more. Therefore, the weight cannot be reduced so much.
In the steel pipe for ground reinforcement of Patent Document 2, it is not necessary to make the pipe body thick enough to form a screw thread, but as long as a general structural carbon steel pipe is used, the wall thickness to a certain extent necessary for ground reinforcement is required. It must be thick and cannot be expected to be light enough to improve workability.
SUMMARY OF THE INVENTION In view of such circumstances, it is an object of the present invention to improve workability by reducing the weight of steel pipes for ground reinforcement that are successively spliced by screw joints while ensuring the required strength.

前記課題を解決するため、本発明は、ネジ接合によって継ぎ足される地山補強用鋼管であって、
ネジ部を有さない管本体と、
内周面又は外周面にネジ部を有し、かつ前記管本体より短く、かつ前記管本体の端部に分離不能に接合された接続管部と、
を備え、前記管本体と前記接続管部の鋼材質が互いに異なり、かつ前記管本体の引張強度が、前記接続管部の引張強度より大きいことを特徴とする。
管本体として接続管部より高引張強度の鋼材質を用いることによって、所要強度を確保しつつ管本体を確実に薄肉にできる。したがって、地山補強用鋼管を軽量化でき、人力で持ち運びしやすく、作業性を改善できる。
また、本発明は、ネジ接合によって継ぎ足される地山補強用鋼管であって、
ネジ部を有さない管本体と、
内周面又は外周面にネジ部を有し、かつ前記管本体より短く、かつ前記管本体の端部に分離不能に接合された接続管部と、
を備え、前記管本体の厚さが前記接続管部の前記ネジ部より管本体側のストレート部の厚さより小さく、前記接続管体が一般構造用炭素鋼鋼管にて構成され、前記管本体が、一般構造用炭素鋼鋼管よりも高引張強度の鋼管にて構成されていることを特徴とする。 In order to solve the above problems, the present invention provides a steel pipe for ground reinforcement that is spliced by screw joint,
a pipe body having no thread;
a connecting pipe portion having a threaded portion on its inner or outer peripheral surface, being shorter than the pipe main body, and inseparably joined to the end of the pipe main body;
wherein the steel materials of the pipe body and the connecting pipe part are different from each other, and the tensile strength of the pipe body is greater than the tensile strength of the connecting pipe part.
By using a steel material having a tensile strength higher than that of the connecting pipe portion for the pipe body, the pipe body can be reliably made thin while ensuring the required strength. Therefore, the weight of the steel pipe for ground reinforcement can be reduced, it can be easily carried by human power, and workability can be improved.
The present invention also provides a steel pipe for ground reinforcement that is spliced by screw joints,
a pipe body having no thread;
a connecting pipe portion having a threaded portion on its inner or outer peripheral surface, being shorter than the pipe main body, and inseparably joined to the end of the pipe main body;
wherein the thickness of the pipe body is smaller than the thickness of the straight portion of the connecting pipe portion closer to the pipe body than the threaded portion, the connecting pipe body is made of a general structural carbon steel pipe, and the pipe body is , characterized by being composed of a steel pipe having a higher tensile strength than a general structural carbon steel pipe.

前記接続管部が、引張強度４００Ｎ／ｍｍ２～５５０Ｎ／ｍｍ２、耐力２３５Ｎ／ｍｍ２～５００Ｎ／ｍｍ２の鋼材によって構成されていることが好ましい。前記接続管部としては、一般構造用炭素鋼鋼管ＳＴＫ４００（ＪＩＳ Ｇ３４４４）を用いることができる。
前記管本体が、引張強度６５０Ｎ／ｍｍ２～１２００Ｎ／ｍｍ２、耐力６００Ｎ／ｍｍ２～９００Ｎ／ｍｍ２の鋼材によって構成されていることが好ましい。前記管本体としては、一般構造用炭素鋼鋼管ＳＴＫ４００よりも高引張強度の鋼管を用いる。これによって、所要強度を確保しながら管本体を確実に薄肉化でき、地山補強用鋼管を確実に軽量化でき、作業性を十分に改善できる。 It is preferable that the connection pipe portion is made of steel having a tensile strength of 400 N/mm 2 to 550 N/mm 2 and a yield strength of 235 N/mm 2 to 500 N/mm 2 . As the connecting pipe portion, a general structural carbon steel pipe STK400 (JIS G3444) can be used.
It is preferable that the pipe main body is made of steel having a tensile strength of 650 N/mm 2 to 1200 N/mm 2 and a yield strength of 600 N/mm 2 to 900 N/mm 2 . As the pipe main body, a steel pipe having a higher tensile strength than the general structural carbon steel pipe STK400 is used. As a result, the wall thickness of the pipe body can be reliably reduced while ensuring the required strength, the weight of the rock reinforcement steel pipe can be reliably reduced, and workability can be sufficiently improved.

前記管本体の厚さが、２．５ｍｍ～４ｍｍであることが好ましい。
管本体にはネジ部を形成する必要がなく、しかも接続管部より高引張強度の鋼材質を用いることによって、このような厚さを実現できる。 It is preferable that the tube body has a thickness of 2.5 mm to 4 mm.
Such a thickness can be realized by using a steel material having a higher tensile strength than that of the connecting pipe portion without the need to form a threaded portion on the pipe body.

本発明によれば、地山補強用鋼管の所要強度を確保するとともに、軽量化でき、作業性を改善することができる。 ADVANTAGE OF THE INVENTION According to this invention, while ensuring the required strength of the steel pipe for ground reinforcement, it can reduce weight and improve workability.

図１は、本発明の一実施形態に係る地山補強用鋼管からなる長尺先受け鋼管を地山に打設する様子を示す、施工中のトンネルの断面図である。FIG. 1 is a cross-sectional view of a tunnel under construction, showing how a long pre-receiving steel pipe made of a steel pipe for ground reinforcement according to one embodiment of the present invention is driven into the ground. 図２（ａ）は、前記地山補強用鋼管の分解正面図である。図２（ｂ）は、前記地山補強用鋼管の断面図である。FIG. 2(a) is an exploded front view of the steel pipe for ground reinforcement. FIG. 2(b) is a cross-sectional view of the steel pipe for ground reinforcement. 図３は、図２（ｂ）の円部ＩＩＩを拡大して示す断面図である。FIG. 3 is a cross-sectional view showing an enlarged circular portion III of FIG. 2(b). 図４は、図２（ｂ）の円部ＩＶを拡大して示す断面図である。FIG. 4 is a cross-sectional view showing an enlarged circular portion IV of FIG. 2(b).

以下、本発明の実施形態を図面にしたがって説明する。
図１は、ＮＡＴＭ工法によって施工中のトンネル１を示したものである。地山２が掘削されてトンネル１が構築されている。トンネル１の軸方向の一定間隔置きに、Ｈ型断面の鋼材からなるアーチ状の支保工３が設置されている。支保工３間の掘削面２ａには、吹付コンクリート４が吹付けられている。支保工３及び吹付コンクリート３の内周側には、二次覆工（図示省略）が構築される。 BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 shows a tunnel 1 under construction by the NATM construction method. A natural ground 2 is excavated and a tunnel 1 is constructed. At regular intervals in the axial direction of the tunnel 1, arch-shaped shorings 3 made of H-shaped section steel are installed. Shotcrete 4 is sprayed on the excavated surface 2 a between the shorings 3 . A secondary lining (not shown) is constructed on the inner peripheral side of the shoring 3 and the shotcrete 3 .

トンネル１の施工においては、地山補強のための補助工法として例えばＡＧＦ工法が実施されている。ＡＧＦ工法においては、ドリルジャンボ５を用いて、複数本（例えば４本程度）の地山補強用鋼管１０を順次継ぎ足しながら、切羽１ｂの前方（図１において右）の地山２に斜めに打ち込み、長尺の先受け鋼管９を形成する。各地山補強用鋼管１０の長さは例えば３ｍ程度である。隣接する地山補強用鋼管１０どうしがネジ接合によって一直線に連なっている。先受け鋼管９の全長は、例えば１２ｍ程度である。
詳細な図示は省略するが、先受け鋼管９のまわりの地山２には、シリカレジンやモルタルなどの注入材が注入されている。 In the construction of the tunnel 1, for example, the AGF construction method is implemented as an auxiliary construction method for ground reinforcement. In the AGF construction method, a drill jumbo 5 is used to sequentially add a plurality of (for example, about four) steel pipes 10 for ground reinforcement, and drive them obliquely into the ground 2 in front of the face 1b (right in FIG. 1). , forming a long pre-receiving steel pipe 9 . The length of each mountain reinforcing steel pipe 10 is, for example, about 3 m. Adjacent ground reinforcement steel pipes 10 are connected in a straight line by screw joints. The overall length of the pre-receiving steel pipe 9 is, for example, about 12 m.
Although detailed illustration is omitted, an injection material such as silica resin or mortar is injected into the ground 2 around the pre-receiving steel pipe 9 .

図２（ａ）及び同図（ｂ）に示すように、地山補強用鋼管１０は、管本体１１と、接続管部２０，３０を有している。
管本体１１は真っ直ぐに延びる直管である。管本体１１の管長は、地山補強用鋼管１０の全長（例えば３ｍ程度）とほぼ同程度であり、管本体１１の外直径は例えば７０ｍｍ～１２０ｍｍ程度である。管本体１１の外周面及び内周面にはネジ部、テーパ部、段差などは形成されておらず、管本体１１の厚みは、該管本体１１の一端部から他端部まで一定である。管本体１１の両端面は、平坦になっており、例えばインロウ型の接合用の段差は形成されていない。 As shown in FIGS. 2( a ) and 2 ( b ), the rock reinforcement steel pipe 10 has a pipe body 11 and connection pipe portions 20 and 30 .
The pipe body 11 is a straight pipe extending straight. The pipe length of the pipe main body 11 is approximately the same as the overall length (for example, about 3 m) of the rock reinforcement steel pipe 10, and the outer diameter of the pipe main body 11 is, for example, about 70 mm to 120 mm. No threaded portion, tapered portion, step, etc. are formed on the outer and inner peripheral surfaces of the pipe body 11, and the thickness of the pipe body 11 is constant from one end to the other end of the pipe body 11. Both end surfaces of the pipe main body 11 are flat, and for example, a spigot-type joining step is not formed.

管本体１１の一端部（図２（ｂ）において右端部）には、接続管部２０が突き当てられて分離不能に接合されている。管本体１１の他端部（図２（ｂ）において左端部）には、接続管部３０が突き当てられて分離不能に接合されている。管本体１１と接続管部２０，３０との接合手段としては、開先溶接（詳細な図示は省略）が適用されているが、これに限らず摩擦圧接などを適用してもよい。接続管部２０，３０の管長は、管本体１１の管長に比べて十分に短い。
なお、先受け鋼管９の最先端の鋼管１０Ｅにおいては、後端部（図１において左下端部）だけに接続管部２０又は３０が設けられていればよい。最後尾の鋼管１０Ｂにおいては、先端部（図１において右上端部）だけに接続管部３０又は２０が設けられていればよい。 One end (the right end in FIG. 2(b)) of the pipe main body 11 is abutted against the connecting pipe portion 20 and joined inseparably. The other end (the left end in FIG. 2(b)) of the pipe body 11 is abutted against the connecting pipe portion 30 and joined inseparably. Groove welding (detailed illustration is omitted) is applied as a means for joining the pipe main body 11 and the connecting pipe portions 20 and 30, but the method is not limited to this, and friction welding or the like may be applied. The pipe lengths of the connecting pipe portions 20 and 30 are sufficiently shorter than the pipe length of the pipe main body 11 .
In addition, in the steel pipe 10E at the forefront of the pre-receiving steel pipe 9, it is sufficient that the connection pipe portion 20 or 30 is provided only at the rear end portion (lower left end portion in FIG. 1). In the rearmost steel pipe 10B, it is sufficient that the connection pipe portion 30 or 20 is provided only at the tip portion (upper right end portion in FIG. 1).

図２（ｂ）に示すように、接続管部２０は、ネジ形成部２１と、ストレート部２２と、テーパ部２３を有している。ネジ形成部２１の外周面に雄ネジ２４（ネジ部）が形成されている。ネジ形成部２１とテーパ部２３との間に、ストレート部２２が設けられている。ネジ形成部２１とストレート部２２の内周面が面一に連続している。ネジ形成部２１及びストレート部２２の内径は、管本体１１の内径より小径である。 As shown in FIG. 2B, the connection tube portion 20 has a threaded portion 21, a straight portion 22, and a tapered portion 23. As shown in FIG. A male thread 24 (screw portion) is formed on the outer peripheral surface of the thread forming portion 21 . A straight portion 22 is provided between the threaded portion 21 and the tapered portion 23 . The inner peripheral surfaces of the threaded portion 21 and the straight portion 22 are flush with each other. The inner diameters of the threaded portion 21 and the straight portion 22 are smaller than the inner diameter of the pipe body 11 .

図３に示すように、テーパ部２３の内周面は、ストレート部２２の内周面と段差無く連なるとともに、管本体１１に向かって拡径されている。テーパ部２３における管本体１１側の端部の内径は、管本体１１の内径と等しい。
ストレート部２２及びテーパ部２３の外径は、管本体１１の外径と等しい。ストレート部２２とテーパ部２３の外周面は面一に連続しており、更には管本体１１の外風面と面一に連続している。 As shown in FIG. 3 , the inner peripheral surface of the tapered portion 23 continues to the inner peripheral surface of the straight portion 22 without a step, and the diameter of the tapered portion 23 increases toward the pipe main body 11 . The inner diameter of the tapered portion 23 at the end on the pipe body 11 side is equal to the inner diameter of the pipe body 11 .
The outer diameters of the straight portion 22 and the tapered portion 23 are equal to the outer diameter of the pipe body 11 . The outer peripheral surfaces of the straight portion 22 and the tapered portion 23 are flush with each other, and are further flush with the outside wind surface of the pipe body 11 .

図２（ｂ）に示すように、接続管部３０は、ネジ形成部３１と、ストレート部３２と、テーパ部３３を有している。ネジ形成部３１の内周面に雌ネジ３４（ネジ部）が形成されている。図２（ｂ）において二点鎖線にて示すように、各地山補強用鋼管１０の雌ネジ３４は、隣接する別の地山補強用鋼管１０の雄ネジ２４と螺合可能である。 As shown in FIG. 2B, the connecting pipe portion 30 has a threaded portion 31, a straight portion 32, and a tapered portion 33. As shown in FIG. A female thread 34 (screw portion) is formed on the inner peripheral surface of the thread forming portion 31 . As indicated by the two-dot chain line in FIG. 2B, the female thread 34 of each rock reinforcement steel pipe 10 can be screwed with the male screw 24 of another adjacent rock reinforcement steel pipe 10 .

ネジ形成部３１とテーパ部３３との間に、ストレート部３２が設けられている。図４に示すように、ストレート部３２の内径は、管本体１１の内径より小径である。テーパ部３３の内周面は、ストレート部３２の内周面と段差無く連なるとともに、管本体１１に向かって拡径されている。テーパ部３３における管本体１１側の端部の内径は、管本体１１の内径と等しい。
図２に示すように、接続管部３０の外径は管本体１１の外径と等しい。接続管部３０の外周面が管本体１１の外周面と面一に連続している。 A straight portion 32 is provided between the threaded portion 31 and the tapered portion 33 . As shown in FIG. 4 , the inner diameter of the straight portion 32 is smaller than the inner diameter of the pipe body 11 . The inner peripheral surface of the tapered portion 33 continues to the inner peripheral surface of the straight portion 32 without a step, and the diameter of the tapered portion 33 increases toward the pipe main body 11 . The inner diameter of the tapered portion 33 at the end on the pipe body 11 side is equal to the inner diameter of the pipe body 11 .
As shown in FIG. 2 , the outer diameter of the connecting pipe portion 30 is equal to the outer diameter of the pipe main body 11 . The outer peripheral surface of the connecting pipe portion 30 continues flush with the outer peripheral surface of the pipe main body 11 .

管本体１１と接続管部２０，３０の鋼材質は互いに異なっている。かつ管本体１１の引張強度が、接続管部２０，３０の引張強度より大きい。
好ましくは、接続管部２０，３０は、引張強度４００Ｎ／ｍｍ２～５５０Ｎ／ｍｍ２、耐力２３５Ｎ／ｍｍ２～５００Ｎ／ｍｍ２の鋼材によって構成されている。かかる接続管部２０，３０用の鋼管として、一般構造用炭素鋼鋼管ＳＴＫ４００（ＪＩＳ Ｇ３４４４）を用いることができる。 The steel materials of the pipe body 11 and the connecting pipe portions 20, 30 are different from each other. Moreover, the tensile strength of the pipe main body 11 is greater than the tensile strength of the connecting pipe portions 20 and 30 .
Preferably, the connecting pipe portions 20 and 30 are made of steel having a tensile strength of 400 N/mm 2 to 550 N/mm 2 and a yield strength of 235 N/mm 2 to 500 N/mm 2 . As steel pipes for the connecting pipe portions 20 and 30, general structural carbon steel pipe STK400 (JIS G3444) can be used.

これに対して、管本体１１としては、一般構造用炭素鋼鋼管ＳＴＫ４００よりも高引張強度の鋼管１０が用いられている。好ましくは、管本体１１は、引張強度６５０Ｎ／ｍｍ２～１２００Ｎ／ｍｍ２、耐力６００Ｎ／ｍｍ２～９００Ｎ／ｍｍ２の鋼材によって構成されている。鋼材に含まれるＣ，Ｓｉ，Ｍｎ，Ｐ，Ｓその他成分の配合比を調整することによって、前記引張強度及び耐力を得ることができる。
管本体１１として、例えば特開２００２－００３９４１に開示された鋼管を用いてもよい。 On the other hand, as the pipe main body 11, a steel pipe 10 having a higher tensile strength than the general structural carbon steel pipe STK400 is used. Preferably, the pipe body 11 is made of steel having a tensile strength of 650 N/mm 2 to 1200 N/mm 2 and a yield strength of 600 N/mm 2 to 900 N/mm 2 . By adjusting the compounding ratio of C, Si, Mn, P, S and other components contained in the steel material, the above tensile strength and yield strength can be obtained.
As the pipe body 11, for example, a steel pipe disclosed in JP-A-2002-003941 may be used.

管本体１１の厚さｔ１１（外半径と内半径との差）は、接続管部２０，３０のストレート部２２，３２の厚さより小さく、好ましくはｔ１１＝２．５ｍｍ～４ｍｍ程度、より好ましくはｔ１１＝２．５ｍｍ～３．５ｍｍ程度である。
なお、接続管部２０，３０のストレート部２２，３２の厚さは、好ましくは５ｍｍ～７ｍｍ程度、より好ましくは６ｍｍ程度である。 The thickness t 11 (difference between the outer radius and the inner radius) of the pipe body 11 is smaller than the thickness of the straight portions 22, 32 of the connecting pipe portions 20, 30, preferably t 11 =2.5 mm to 4 mm, or more. Preferably, t 11 =2.5 mm to 3.5 mm.
The thickness of the straight portions 22, 32 of the connecting pipe portions 20, 30 is preferably about 5 mm to 7 mm, more preferably about 6 mm.

かかる地山補強用鋼管１０によれば、管本体１１として接続管部２０，３０より高引張強度及び高耐力の鋼材質を用いることによって、所要強度を確保しつつ管本体１１を確実に薄肉にできる。しかも、管本体１１には、ネジ２４，３４を形成する必要がなく、一層薄肉化できる。したがって、管本体１１ひいては地山補強用鋼管１０を軽量化でき、人力で持ち運びやすくなり作業性を改善できる。 According to the ground reinforcement steel pipe 10, by using a steel material having a higher tensile strength and a higher yield strength than the connection pipe parts 20 and 30 for the pipe body 11, the pipe body 11 can be reliably made thin while ensuring the required strength. can. Moreover, it is not necessary to form the threads 24 and 34 on the pipe main body 11, so that the pipe body 11 can be further thinned. Therefore, the weight of the pipe main body 11 and thus the steel pipe 10 for ground reinforcement can be reduced, and it is easy to carry by human power, and workability can be improved.

例えば、一般的なＡＧＦ工法における地山補強用鋼管の標準スペック（肉厚６ｍｍ、外直径１１４．３ｍｍ、長さ３ｍ）の場合、重量が約５０ｋｇであるのに対し、本発明態様の地山補強用鋼管１０においては、管本体１１を引張強度８００Ｎ／ｍｍ２、厚さ３．２ｍｍ、外直径１１４．３ｍｍ、長さ３ｍとした場合、重量が約３０ｋｇとなる。したがって、約４０％の軽量化を実現できる。 For example, in the case of standard specs (6 mm thick, 114.3 mm outer diameter, 3 m in length) of a steel pipe for ground reinforcement in a general AGF construction method, the weight is about 50 kg. The reinforcing steel pipe 10 weighs about 30 kg when the pipe body 11 has a tensile strength of 800 N/mm 2 , a thickness of 3.2 mm, an outer diameter of 114.3 mm, and a length of 3 m. Therefore, weight reduction of about 40% can be realized.

管本体１１には、ネジ部、テーパ部、段差その他の形状変化部が設けられていないから、切削などの加工を施す必要がない。したがって、加工容易性を考慮することなく、管本体１１の強度を設定できる。 Since the pipe main body 11 is not provided with a threaded portion, a tapered portion, a stepped portion, or other shape-changing portion, it is not necessary to perform processing such as cutting. Therefore, the strength of the pipe body 11 can be set without considering ease of processing.

地山補強用鋼管１０の管本体１１の内周面と、接続管部２０，３０のネジ形成部２１，３１の内周面との間にテーパ部２３，３３を設けておくことによって、パイロットビット６（図１）の抜き差し時における引っ掛かりを防止できる。また、長尺先受け鋼管９の内部に入り込んだ土砂をスムーズに排出できる。 By providing the tapered portions 23, 33 between the inner peripheral surface of the pipe main body 11 of the rock reinforcement steel pipe 10 and the inner peripheral surfaces of the thread forming portions 21, 31 of the connecting pipe portions 20, 30, the pilot It is possible to prevent the bit 6 (FIG. 1) from being caught when inserting and removing it. In addition, the earth and sand that have entered the inside of the long pre-receiving steel pipe 9 can be discharged smoothly.

本発明は、前記実施形態に限定されるものではなく、その趣旨を逸脱しない範囲において種々の改変をなすことができる。
例えば、本発明の鋼管は、ＡＧＦ工法用の先受け鋼管に限らず、鏡補強工用の鋼管、地中杭用の鋼管としても適用可能である。 The present invention is not limited to the embodiments described above, and various modifications can be made without departing from the scope of the invention.
For example, the steel pipe of the present invention is applicable not only as a pre-receiving steel pipe for the AGF construction method, but also as a steel pipe for mirror reinforcement work and a steel pipe for underground piles.

本発明は、例えばＡＧＦ工法用の先受け鋼管に適用できる。 INDUSTRIAL APPLICABILITY The present invention can be applied, for example, to pre-received steel pipes for the AGF construction method.

１ トンネル
２ 地山
２ａ 掘削面
３ 支保工
４ 吹付コンクリート
５ ドリルジャンボ
６ パイロットビット
９ 長尺先受け鋼管
１０ 地山補強用鋼管
１１ 管本体
２０ 雄ネジ管部（接続管部）
２１ ネジ形成部
２２ ストレート部
２３ テーパ部
２４ 雄ネジ（ネジ部）
３０ 接続管部
３１ ネジ形成部
３２ ストレート部
３３ テーパ部
３４ 雌ネジ（ネジ部） 1 Tunnel 2 Rock 2a Excavated surface 3 Shoring 4 Shotcrete 5 Drill jumbo 6 Pilot bit 9 Long steel pipe 10 Rock reinforcement steel pipe 11 Pipe main body 20 Male screw pipe (connecting pipe)
21 threaded portion 22 straight portion 23 tapered portion 24 male screw (screw portion)
30 Connection tube portion 31 Thread forming portion 32 Straight portion 33 Tapered portion 34 Female thread (thread portion)

Claims (2)

ネジ接合によって継ぎ足される地山補強用鋼管であって、
ネジ部を有さない管本体と、
内周面又は外周面にネジ部を有し、かつ前記管本体より短く、かつ前記管本体の端部に分離不能に接合された接続管部と、
を備え、前記管本体の厚さが前記接続管部の前記ネジ部より管本体側のストレート部の厚さより小さく、前記接続管体が一般構造用炭素鋼鋼管にて構成され、前記管本体が、一般構造用炭素鋼鋼管よりも高引張強度の鋼管にて構成されていることを特徴とする地山補強用鋼管。 A steel pipe for ground reinforcement that is spliced by screw joints,
a pipe body having no thread;
a connecting pipe portion having a threaded portion on its inner or outer peripheral surface, being shorter than the pipe main body, and inseparably joined to the end of the pipe main body;
wherein the thickness of the pipe body is smaller than the thickness of the straight portion of the connecting pipe portion closer to the pipe body than the threaded portion, the connecting pipe body is made of a general structural carbon steel pipe, and the pipe body is A steel pipe for ground reinforcement, comprising a steel pipe having a tensile strength higher than that of a general structural carbon steel pipe. 前記管本体が、引張強度６５０Ｎ／ｍｍ２～１２００Ｎ／ｍｍ２、耐力６００Ｎ／ｍｍ２～９００Ｎ／ｍｍ２の鋼材によって構成された請求項１に記載の地山補強用鋼管。 The steel pipe for ground reinforcement according to claim 1, wherein the pipe main body is made of a steel material having a tensile strength of 650 N/mm 2 to 1200 N/mm 2 and a yield strength of 600 N/mm 2 to 900 N/mm 2 .
JP2022189311A 2018-10-24 2022-11-28 Steel pipe for ground reinforcement Active JP7366381B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2022189311A JP7366381B2 (en) 2018-10-24 2022-11-28 Steel pipe for ground reinforcement

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2018199721A JP7193789B2 (en) 2018-10-24 2018-10-24 Steel pipe for ground reinforcement
JP2022189311A JP7366381B2 (en) 2018-10-24 2022-11-28 Steel pipe for ground reinforcement

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
JP2018199721A Division JP7193789B2 (en) 2018-10-24 2018-10-24 Steel pipe for ground reinforcement

Publications (2)

Publication Number Publication Date
JP2023016904A true JP2023016904A (en) 2023-02-02
JP7366381B2 JP7366381B2 (en) 2023-10-23

Family

ID=70389795

Family Applications (2)

Application Number Title Priority Date Filing Date
JP2018199721A Active JP7193789B2 (en) 2018-10-24 2018-10-24 Steel pipe for ground reinforcement
JP2022189311A Active JP7366381B2 (en) 2018-10-24 2022-11-28 Steel pipe for ground reinforcement

Family Applications Before (1)

Application Number Title Priority Date Filing Date
JP2018199721A Active JP7193789B2 (en) 2018-10-24 2018-10-24 Steel pipe for ground reinforcement

Country Status (1)

Country Link
JP (2) JP7193789B2 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP7281572B2 (en) * 2021-01-26 2023-05-25 フジモリ産業株式会社 Ground reinforcement steel pipe
JP7044911B1 (en) 2021-01-26 2022-03-30 フジモリ産業株式会社 Ground reinforced steel pipe and its joint pipe

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003164941A (en) * 2001-11-29 2003-06-10 High Frequency Heattreat Co Ltd Hollow steering rack shaft and method for manufacturing the same
JP2012255318A (en) * 2011-06-10 2012-12-27 Kajima Corp Expansion-type lock bolt having protrusion
JP2014181551A (en) * 2013-03-21 2014-09-29 Nippon Steel & Sumitomo Metal Recessed steel pipe joint, joint steel pipe, and joint method of steel pipe
JP2015110994A (en) * 2013-10-29 2015-06-18 新日鐵住金株式会社 Steel pipe screw coupling

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003164941A (en) * 2001-11-29 2003-06-10 High Frequency Heattreat Co Ltd Hollow steering rack shaft and method for manufacturing the same
JP2012255318A (en) * 2011-06-10 2012-12-27 Kajima Corp Expansion-type lock bolt having protrusion
JP2014181551A (en) * 2013-03-21 2014-09-29 Nippon Steel & Sumitomo Metal Recessed steel pipe joint, joint steel pipe, and joint method of steel pipe
JP2015110994A (en) * 2013-10-29 2015-06-18 新日鐵住金株式会社 Steel pipe screw coupling

Also Published As

Publication number Publication date
JP7366381B2 (en) 2023-10-23
JP2020066908A (en) 2020-04-30
JP7193789B2 (en) 2022-12-21

Similar Documents

Publication Publication Date Title
JP2023016904A (en) Ground reinforcement steel pipe
JP6390321B2 (en) Threaded joints for steel pipes
JP6395524B2 (en) Steel pipe for ground reinforcement and method for manufacturing the same
JP4942211B2 (en) Ground reinforcement method
JP7165347B2 (en) Excavation method using pre-received steel pipes for tunnel construction
JP2012149458A (en) Natural ground reinforcement method
JP7037785B2 (en) Ground reinforcement pipe
JP2019056285A (en) Ground-embedded steel pipe
JP2012158969A (en) Natural ground reinforcing steel pipe
KR100986668B1 (en) Assembly and separation steel pipe structure for reinforcng tunnel face
JP6071127B2 (en) Coupling structure of natural ground reinforcement pipe, coupler and natural ground reinforcement pipe
JP2012144964A (en) Natural ground reinforcing steel pipe
JP2013113080A (en) Steel pipe for natural ground reinforcement
JP7281572B2 (en) Ground reinforcement steel pipe
JP6208912B1 (en) Ground buried steel pipe
JP3350679B2 (en) Tunnel lining segment and construction method
JP4266851B2 (en) Propulsion drilling rig
JP7044911B1 (en) Ground reinforced steel pipe and its joint pipe
JP5161948B2 (en) Promotion method
JP3500371B2 (en) Buried pipe for double pipe drilling
JP2008156997A (en) Segment piece, lining body having this segment piece and tunnel
JP4246344B2 (en) Tunnel long steel pipe tip receiving method
JP2023068811A (en) Steel pipe reinforcement member, ground reinforcement construction method, and ground reinforcement structure
JP7175200B2 (en) Pre-receiving steel pipe for tunnel and pre-receiving construction method
JP3373396B2 (en) Propulsion method and pipe joint structure

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20221128

A521 Request for written amendment filed

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20230106

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20230627

A521 Request for written amendment filed

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20230828

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20230912

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20231002

R150 Certificate of patent or registration of utility model

Ref document number: 7366381

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R150