JP6071280B2

JP6071280B2 - Earthing sheet pile

Info

Publication number: JP6071280B2
Application number: JP2012149351A
Authority: JP
Inventors: 正嗣森; 竹中　計行; 計行竹中; 将則白子; 道成兼本; 澤田　栄嗣; 栄嗣澤田
Original assignee: DIC Corp
Current assignee: DIC Corp
Priority date: 2012-07-03
Filing date: 2012-07-03
Publication date: 2017-02-01
Anticipated expiration: 2032-07-03
Also published as: JP2014009577A

Description

本発明は、土留め用矢板に関する。 The present invention relates to a sheet pile for earth retaining.

従来から、土留め用矢板として主に鋼矢板が用いられている。このような鋼矢板としては、用途、使用形態、経済性等の面からそれぞれの目的に応じて、直線型、Ｕ形、ハット型、曲げ成形型に構成されたものがある。特に、構造的に強靭でかつ低コストの鋼矢板が求められており、例えば、特許文献１には、Ｈ型の構造の鋼矢板が開示されている。 Conventionally, steel sheet piles have been mainly used as earth retaining sheet piles. Such steel sheet piles include those configured in a linear shape, a U shape, a hat shape, and a bending shape mold in accordance with their respective purposes from the viewpoints of usage, usage pattern, economy, and the like. In particular, a structurally strong and low-cost steel sheet pile is required. For example, Patent Document 1 discloses a steel sheet pile having an H-type structure.

一方、従来、シールド掘進機等によって地盤を掘削するときは、シールド掘進機の前方に設けられた鋼矢板のシールド掘進機等が通過する部分を、ガスによって溶断し掘削する鏡切りという工法が知られている（特許文献２）。
この工法は、鋼矢板の一部をガスによって溶断するので、手間がかかることや、地盤を剥き出しにするため地盤の強度によっては崩壊する虞がある。 On the other hand, conventionally, when excavating the ground with a shield machine, etc., a method called mirror cutting that cuts and excavates the part of the steel sheet pile provided in front of the shield machine through which the shield machine passes is known. (Patent Document 2).
In this construction method, a part of the steel sheet pile is melted by gas, so that it takes time and there is a risk of collapse depending on the strength of the ground to expose the ground.

このように、通常、土留め用矢板として特許文献１及び特許文献２で開示されているような従来の鋼矢板を用いると、シールド掘進機等より下側にある部分の鋼矢板は通常撤去されず、地中内に剛性の高い鉄材である鋼矢板が残ったままとなる。地中内に鋼矢板が残ったままとなると、シールド掘進機等のカッター部では残存した鋼矢板を切削することができない場合がある。このため、シールド掘進機等で地盤の掘削工事が終了した後にその最深床部の下に更にトンネル等を作ろうとした場合、残存した鋼矢板を避けるため、地中のより深くなる方向へトンネル等の路線を変更しなければならないという問題があった。 As described above, when a conventional steel sheet pile as disclosed in Patent Document 1 and Patent Document 2 is used as a retaining sheet pile, the steel sheet pile in the lower part of the shield machine is usually removed. The steel sheet pile, which is a highly rigid iron material, remains in the ground. If the steel sheet pile remains in the ground, the remaining steel sheet pile may not be cut by a cutter unit such as a shield machine. For this reason, when an attempt is made to create a tunnel or the like under the deepest floor after the ground excavation work is completed with a shield machine or the like, a tunnel or the like is formed in a direction deeper in the ground to avoid the remaining steel sheet pile. There was a problem of having to change the route.

特開２００５−３４４４４７号公報JP 2005-344447 A 特開２００６−２５７８２６号公報JP 2006-257826 A

この問題を解決する手段として、シールド掘進機等のカッター部で切削することが可能な易切削部材で土留め用矢板を作製し使用することが考えられる。しかし、易切削部材のみで作成された土留め用矢板は全体的な強度が足りない場合やコストが高くなる場合がある。また、これらの課題を解決するため、必要部分のみに易切削部材の矢板を用いた、鋼矢板と易切削部材の矢板とを連結させた土留め用矢板を作製し使用することが考えられる。 As a means for solving this problem, it is conceivable to prepare and use a sheet pile for earth retaining with an easy-cutting member that can be cut by a cutter unit such as a shield machine. However, the earth retaining sheet pile made only of the easy-cutting member may have insufficient overall strength or cost. Further, in order to solve these problems, it is conceivable to produce and use a sheet pile for earth retaining in which only a necessary portion uses a sheet pile of an easy-cutting member and connects a steel sheet pile and a sheet pile of an easy-cutting member.

しかしながら、鋼矢板と易切削部材の矢板とを連結させた土留め用矢板を作製し使用するためには、連結部の強度を高くするために大きな継手部材を使用する等、連結部を大きくする必要があった。連結部が大きくなるとサイレントパイラー等の汎用の圧入機を使用することができなくなる。連結部が汎用の圧入機に用いられる把持機構を通過できなくなるためである。
このため、強度が高く汎用の圧入機を使用することが可能な大きさの連結部を備え、該連結部で鋼矢板と易切削部材の矢板とを連結させた土留め用矢板が求められている。 However, in order to manufacture and use a sheet pile for earth retaining in which a steel sheet pile and a sheet pile of an easy-cutting member are connected, a large joint member is used to increase the strength of the connecting part, and the connecting part is enlarged. There was a need. If the connecting portion becomes large, a general-purpose press-fitting machine such as a silent pillar cannot be used. This is because the connecting portion cannot pass through a gripping mechanism used in a general-purpose press-fitting machine.
For this reason, there is a demand for a sheet pile for earth retaining that has a connecting portion of a size that can use a general-purpose press-fitting machine with high strength, and that connects a steel sheet pile and a sheet pile of an easy-cutting member at the connecting portion. Yes.

そこで、本発明の目的は、鋼矢板と易切削部材の矢板とを強度が高く小さな連結部で連結させた土留め用矢板を提供することにある。 Then, the objective of this invention is providing the sheet pile for earth retaining which connected the steel sheet pile and the sheet pile of the easy-cutting member with high intensity | strength and a small connection part.

上記課題を解決するための本発明の第１の態様に係る土留め用矢板は、鋼矢板と易切削部材の矢板とが継手部材で連結された土留め用矢板であって、前記継手部材と前記鋼矢板とは溶接により接合され、前記継手部材と前記易切削部材の矢板とは接合部材を用いて接合されていることを特徴とする。 The sheet pile for earth retaining according to the first aspect of the present invention for solving the above-mentioned problem is a sheet pile for earth retaining in which a steel sheet pile and a sheet pile of an easy-cutting member are connected by a joint member, and the joint member and The steel sheet pile is joined by welding, and the joint member and the sheet pile of the easy-cutting member are joined using a joining member.

本態様によれば、前記継手部材と前記鋼矢板とは溶接により接合されるため、接合間のすべりやズレ等が発生しにくく、前記継手部材と前記鋼矢板との接合強度を高くすることができる。このため、前記鋼矢板と前記易切削部材の矢板との連結方向における前記継手部材と前記鋼矢板との接合部の長さを短くすることが可能になる。つまり、前記連結方向における前記継手部材と前記易切削部材の矢板との接合部の長さを、前記連結方向における前記継手部材と前記鋼矢板との接合部の長さよりも長くすることが可能になる。こうして、前記継手部材と前記易切削部材の矢板との接合強度を高くすることが可能になる。このため、前記継手部材と前記鋼矢板との接合強度と、前記継手部材と前記易切削部材の矢板との接合強度とを、共に効率よく高くすることが可能になり、前記継手部材を小さくすることが可能になる。すなわち、強度が高く小さな連結部とすることが可能になる。 According to this aspect, since the joint member and the steel sheet pile are joined by welding, slippage or displacement between joints is unlikely to occur, and the joint strength between the joint member and the steel sheet pile can be increased. it can. For this reason, it becomes possible to shorten the length of the junction part of the said joint member and the said steel sheet pile in the connection direction of the said steel sheet pile and the sheet pile of the said easy-cutting member. That is, the length of the joint portion between the joint member and the sheet pile of the easy-cutting member in the connection direction can be made longer than the length of the joint portion between the joint member and the steel sheet pile in the connection direction. Become. Thus, it is possible to increase the bonding strength between the joint member and the sheet pile of the easy-cutting member. For this reason, it is possible to efficiently increase the joint strength between the joint member and the steel sheet pile and the joint strength between the joint member and the sheet pile of the easy-cutting member, thereby reducing the joint member. It becomes possible. That is, it is possible to make the connecting portion high in strength and small.

本発明の第２の態様に係る土留め用矢板は、前記第１の態様において、前記鋼矢板と前記易切削部材の矢板との連結方向における前記継手部材と前記易切削部材の矢板との接合部の長さは、前記連結方向における前記継手部材と前記鋼矢板との接合部の長さよりも長いことを特徴とする。 A sheet pile for earth retaining according to a second aspect of the present invention is the first aspect, wherein the joint member and the sheet pile of the easy-cut member in the connecting direction of the steel sheet pile and the sheet pile of the easy-cut member are joined. The length of a part is longer than the length of the junction part of the said joint member and the said steel sheet pile in the said connection direction, It is characterized by the above-mentioned.

本態様によれば、前記鋼矢板と前記易切削部材の矢板との連結方向における前記継手部材と前記易切削部材の矢板との接合部の長さは、前記連結方向における前記継手部材と前記鋼矢板との接合部の長さよりも長い。このため、前記継手部材と前記鋼矢板との接合強度と、前記継手部材と前記易切削部材の矢板との接合強度とを、共に効率よく高くすることができ、前記継手部材を小さくすることができる。すなわち、強度が高く小さな連結部とすることができる。 According to this aspect, the length of the joint portion between the joint member and the sheet pile of the easy-cutting member in the connecting direction of the steel sheet pile and the easy-cutting member of the sheet pile is the joint member and the steel in the connecting direction. It is longer than the length of the joint with the sheet pile. For this reason, both the joint strength between the joint member and the steel sheet pile and the joint strength between the joint member and the sheet pile of the easy-cutting member can be efficiently increased, and the joint member can be made smaller. it can. That is, it can be set as a small connection part with high intensity | strength.

本発明の第３の態様に係る土留め用矢板は、前記第１又は２の態様において、前記易切削部材の矢板の材料は繊維強化プラスチックであることを特徴とする。 The earth retaining sheet pile according to the third aspect of the present invention is characterized in that, in the first or second aspect, a material of the sheet pile of the easy-cutting member is a fiber reinforced plastic.

本態様によれば、易切削部材の材料が繊維強化プラスチックであるため、従来の鋼矢板よりも容易にシールド掘削機等のカッター部で切削することができる。また、各形状への成形加工が容易に行える。 According to this aspect, since the material of the easy-cutting member is fiber reinforced plastic, it can be cut with a cutter unit such as a shield excavator more easily than a conventional steel sheet pile. Moreover, the shaping | molding process to each shape can be performed easily.

本発明の第４の態様に係る土留め用矢板は、前記第１から３のいずれか１項の態様において、前記土留め用矢板は、該土留め用矢板を把持可能な把持機構と該把持機構を往復移動させることが可能な移動機構とを備えた圧入機で用いられることが可能であって、前記継手部材における前記連結方向の長さは、前記移動機構による前記把持機構の往復移動可能距離に対応した長さ以下であり、前記継手部材を用いて連結された連結部における該継手部材と前記鋼矢板及び前記易切削部材の矢板との接触方向の厚さは、前記把持機構が把持可能な厚さ以下であることを特徴とする。 The earth retaining sheet pile according to a fourth aspect of the present invention is the aspect of any one of the first to third aspects, wherein the earth retaining sheet pile is configured to grasp the earth retaining sheet pile and the gripping mechanism. The joint mechanism can be used in a press-fitting machine having a moving mechanism capable of reciprocating the mechanism, and the length of the coupling member in the coupling direction can be reciprocated by the gripping mechanism by the moving mechanism. The thickness in the contact direction between the joint member, the steel sheet pile, and the sheet pile of the easy-cutting member at the connecting portion connected using the joint member is equal to or less than the length corresponding to the distance. The thickness is less than the possible thickness.

ここで、「土留め用矢板を把持可能な把持機構」とは、前記土留め用矢板を内部に設けられた挿入穴に挿入して把持する機構の他、前記土留め用矢板を挟んで把持する機構も含む。さらに、前記土留め用矢板の把持と解放とを繰り返し行うことができる機構を含む。また、「把持機構を往復移動させることが可能な移動機構」とは、前記土留め用矢板を把持した把持機構を往復移動させることが可能な移動機構を意味する。このため、前記圧入機は、該把持機構と該移動機構とを備えることで、該把持機構に前記土留め用矢板の把持と解放とを繰り返させながら該移動機構が該把持機構を往復移動させることができる。すなわち、前記圧入機はこのような動作を行うことにより前記土留め用矢板を地中に挿入することができる。 Here, “the gripping mechanism capable of gripping the earth retaining sheet pile” refers to a mechanism that inserts and holds the earth retaining sheet pile into an insertion hole provided therein, and also holds the earth retaining sheet pile in between. It also includes a mechanism for Furthermore, a mechanism capable of repeatedly holding and releasing the earth retaining sheet pile is included. Further, the “moving mechanism capable of reciprocating the gripping mechanism” means a moving mechanism capable of reciprocating the gripping mechanism that grips the earth retaining sheet pile. For this reason, the press-fitting machine includes the gripping mechanism and the moving mechanism, and the moving mechanism reciprocates the gripping mechanism while causing the gripping mechanism to repeatedly grip and release the earth retaining sheet pile. be able to. That is, the press-fitting machine can insert the earth retaining sheet pile into the ground by performing such an operation.

また、「前記移動機構による前記把持機構の往復移動可能距離」及び「前記把持機構が把持可能な厚さ」は、ほとんどの汎用の圧入機において共通化されている。このため、このことを踏まえて「前記継手部材の長さ」及び「前記連結部の厚さ」を決めることで、汎用の圧入機において、改造等を行うことなくそのまま前記土留め用矢板を使用することが可能になる。 Further, “the reciprocable distance of the gripping mechanism by the moving mechanism” and “the thickness that the gripping mechanism can grip” are common to most general-purpose press-fitting machines. For this reason, by determining the “length of the joint member” and the “thickness of the connecting portion” based on this fact, in the general-purpose press-fitting machine, the earth retaining sheet pile is used as it is without modification. It becomes possible to do.

本態様によれば、前記継手部材における前記鋼矢板と前記易切削部材の矢板との連結方向の長さは、前記移動機構による前記把持機構の往復移動可能距離に対応した長さ以下である。また、前記継手部材を用いて連結された連結部における該継手部材と前記鋼矢板及び前記易切削部材の矢板との接触方向の厚さは、前記把持機構が把持可能な厚さ以下である。このため、前記把持機構の１回の往復移動によって、前記継手部材は前記把持機構を通過することができる。すなわち、前記把持機構に前記継手部材を把持させることなく、前記土留め用矢板を地中に挿入することができる。 According to this aspect, the length of the connection direction of the steel sheet pile and the sheet pile of the easy-cutting member in the joint member is equal to or less than the length corresponding to the reciprocable distance of the gripping mechanism by the moving mechanism. Moreover, the thickness in the contact direction between the joint member, the steel sheet pile, and the sheet pile of the easy-cutting member in the connecting portion connected using the joint member is equal to or less than a thickness that the gripping mechanism can grip. For this reason, the joint member can pass through the gripping mechanism by one reciprocating movement of the gripping mechanism. That is, the earth retaining sheet pile can be inserted into the ground without causing the gripping mechanism to grip the joint member.

本発明の第５の態様に係る土留め用矢板は、前記第４の態様において、前記継手部材の前記連結方向の長さは５００ｍｍ以下であり、前記連結部の前記接触方向の厚さは５０ｍｍ以下であることを特徴とする。 The retaining sheet pile according to a fifth aspect of the present invention is the fourth aspect, wherein the length of the joint member in the connecting direction is 500 mm or less, and the thickness of the connecting portion in the contact direction is 50 mm. It is characterized by the following.

本態様によれば、サイレントパイラー等の汎用の圧入機は、大凡、移動機構による把持機構の往復移動可能距離は５００ｍｍ以下、把持機構の把持可能な厚さは５０ｍｍ以下であるため、このような圧入機で使用することが可能である。 According to this aspect, a general-purpose press-fitting machine such as a silent pillar generally has a reciprocating distance of the gripping mechanism by the moving mechanism of 500 mm or less and a grippable thickness of the gripping mechanism of 50 mm or less. It can be used with a press-fitting machine.

本発明の第６の態様に係る土留め用矢板は、前記第１から第５のいずれか１つの態様において、前記接合部材はボルトを有することを特徴とする。 The earth retaining sheet pile according to a sixth aspect of the present invention is characterized in that, in any one of the first to fifth aspects, the joining member has a bolt.

ここで、「ボルト」とは、ナットと共に部材を接合するものだけでなく、該ボルトに設けられたネジ山を部材に設けられたネジ穴に嵌合させることにより、ナットを用いず直接部材を接合するものも含む。 Here, the “bolt” is not only a member that joins a member together with a nut, but also by directly fitting a member without using a nut by fitting a screw thread provided on the bolt into a screw hole provided on the member. Includes those to be joined.

本態様によれば、低コストで簡単な構成で前記継手部材と前記易切削部材の矢板とを接合することができる。 According to this aspect, the joint member and the sheet pile of the easy-cutting member can be joined with a simple configuration at low cost.

本発明の第７の態様に係る土留め用矢板は、前記第６の態様において、前記接合部材は、前記継手部材及び前記易切削部材の矢板と前記ボルトとの隙間を充填する充填部材を有することを特徴とする。 The retaining sheet pile according to a seventh aspect of the present invention is the sixth aspect, wherein the joining member has a filling member that fills a gap between the joint member and the easily cut member sheet pile and the bolt. It is characterized by that.

本態様によれば、前記継手部材及び前記易切削部材の矢板と前記ボルトとの隙間がなくなる。該隙間がなくなれば、土留め用矢板が外部から力を受けた場合でも、接合間のすべりやズレ等が発生しにくく接合強度が高くなる。また、該隙間がなくなれば、そこから土や水等が侵入せず、安全に掘削作業をすることが可能となる。 According to this aspect, there is no gap between the joint member and the sheet pile of the easy-cutting member and the bolt. If the gap is eliminated, even when the earth retaining sheet pile receives a force from the outside, slippage or displacement between the joints hardly occurs and the joint strength increases. Further, when the gap is eliminated, soil and water do not enter from there, and it is possible to perform excavation work safely.

本発明の第８の態様に係る土留め用矢板は、前記第１から第７のいずれか１つの態様において、前記継手部材と前記鋼矢板及び前記易切削部材の矢板との接触方向の該易切削部材の矢板の厚さは、該方向における該鋼矢板の厚さよりも厚いことを特徴とする。 The earth retaining sheet pile according to an eighth aspect of the present invention is the ease of the contact direction between the joint member, the steel sheet pile, and the sheet pile of the easy-cutting member in any one of the first to seventh aspects. The thickness of the sheet pile of the cutting member is characterized by being thicker than the thickness of the steel sheet pile in this direction.

本態様によれば、一般的に鋼矢板より単位体積当たりの強度が弱い易切削部材の矢板の強度を鋼矢板と同様に高めることができる。 According to this aspect, the strength of the sheet pile of the easy-cutting member whose strength per unit volume is generally weaker than that of the steel sheet pile can be increased similarly to the steel sheet pile.

本発明の第９の態様に係る土留め用矢板は、前記第８の態様において、前記継手部材は、前記易切削部材の矢板の厚さと前記鋼矢板の厚さとの差に対応した切欠き深さの切欠き部を該易切削部材の矢板と接触する側に有し、前記易切削部材の矢板は、前記切欠き部に接合されることを特徴とする。 The retaining sheet pile according to a ninth aspect of the present invention is the notch depth according to the eighth aspect, wherein the joint member corresponds to a difference between a thickness of the sheet pile of the easy-cutting member and a thickness of the steel sheet pile. It has a notch part on the side that contacts the sheet pile of the easy-cutting member, and the sheet pile of the easy-cutting member is joined to the notch part.

本態様によれば、前記継手部材と前記鋼矢板との接合部の厚さと、前記継手部材と前記易切削部材の矢板との接合部の厚さとを、同様にすることができる。すなわち、前記継手部材と前記易切削部材の矢板との接合部の厚さが前記継手部材と前記鋼矢板との接合部の厚さよりも厚い形状ではなくなり、連結部全体の厚さを薄くすることができる。 According to this aspect, the thickness of the joint portion between the joint member and the steel sheet pile can be made similar to the thickness of the joint portion between the joint member and the sheet pile of the easy-cutting member. That is, the thickness of the joint portion between the joint member and the sheet pile of the easy-cutting member is not thicker than the thickness of the joint portion between the joint member and the steel sheet pile, and the thickness of the entire connection portion is reduced. Can do.

本発明の第１０の態様に係る土留め用矢板は、前記第８の態様において、前記易切削部材の矢板は、前記易切削部材の矢板の厚さと前記鋼矢板の厚さとの差に対応した切欠き深さの切欠き部を前記鋼矢板と連結する側に有し、前記接合部材は、前記切欠き部に接合されることを特徴とする。 In the eighth aspect, the sheet pile for earth retaining according to the tenth aspect of the present invention corresponds to the difference between the thickness of the sheet pile of the easy-cut member and the thickness of the steel sheet pile in the eighth aspect. A notch portion having a notch depth is provided on the side connected to the steel sheet pile, and the joining member is joined to the notch portion.

本発明の第１１の態様に係る土留め用矢板は、前記第１から第１０のいずれか１つの態様において、前記易切削部材の矢板における曲げ弾性率と矢板１枚当たりの断面二次モーメントとの積で表される曲げ剛性は、鋼矢板における曲げ剛性の２５％以上であることを特徴とする。 The earth retaining sheet pile according to an eleventh aspect of the present invention is the sheet pile sheet pile according to any one of the first to tenth aspects, wherein the bending elastic modulus in the sheet pile of the easy-cutting member and the sectional moment of inertia per sheet pile The bending stiffness represented by the product of is characterized by being 25% or more of the bending stiffness of the steel sheet pile.

本態様によれば、曲げ剛性の高い土留め用矢板とすることができる。 According to this aspect, it can be set as the sheet pile for earth retaining with high bending rigidity.

本発明の第１２の態様に係る土留め用矢板は、前記第１から第１１のいずれか１つの態様において、前記易切削部材の矢板の材料は、ガラス繊維及び炭素繊維の少なくとも一方或いは両方を合計で３０質量％以上含有する繊維強化プラスチックであることを特徴とする。 The retaining sheet pile according to a twelfth aspect of the present invention is the sheet pile according to any one of the first to eleventh aspects, wherein the material of the easy-cutting sheet pile is at least one or both of glass fiber and carbon fiber. It is a fiber reinforced plastic containing 30% by mass or more in total.

本態様によれば、高い強度と優れた切削性とを両立する易切削部材の矢板を使用した土留め用矢板とすることができる。 According to this aspect, it can be set as the sheet pile for earth retaining which uses the sheet pile of the easy-cutting member which makes high intensity | strength and outstanding machinability compatible.

本発明の土留め用矢板を使用可能な圧入機の一例を示す概要図である。It is a schematic diagram which shows an example of the press injection machine which can use the sheet pile for earth retaining of this invention. 本発明の実施例１−３に係る土留め用矢板の要部概要図である。It is a principal part schematic diagram of the sheet pile for earth retaining which concerns on Example 1-3 of this invention. 本発明の実施例１に係る土留め用矢板の要部拡大図である。It is a principal part enlarged view of the sheet pile for earth retaining which concerns on Example 1 of this invention. 本発明の実施例４−６に係る土留め用矢板の要部概要図である。It is a principal part schematic diagram of the sheet pile for earth retaining based on Example 4-6 of this invention. 本発明の実施例７に係る土留め用矢板の要部概要図である。It is a principal part schematic diagram of the sheet pile for earth retaining based on Example 7 of this invention. 本発明の実施例８に係る土留め用矢板の要部概要図である。It is a principal part schematic diagram of the sheet pile for earth retaining based on Example 8 of this invention. 本発明の実施例９−１０に係る土留め用矢板の要部概要図である。It is a principal part schematic diagram of the sheet pile for earth retaining based on Example 9-10 of this invention.

以下に、本発明について実施例に基づき詳細に説明する。ただし、本発明はこれらの実施例に制約されるわけではない。
最初に、本発明の土留め用矢板を使用可能な圧入機について説明する。
図１は、本発明の土留め用矢板を使用可能な圧入機の一例を示す概要図である。 Hereinafter, the present invention will be described in detail based on examples. However, the present invention is not limited to these examples.
First, a press-fitting machine that can use the retaining sheet pile of the present invention will be described.
FIG. 1 is a schematic diagram showing an example of a press-fitting machine that can use the retaining sheet pile of the present invention.

図１（Ａ）は、圧入機１の全体の概要図を示している。
圧入機１は機械本体部２とチャック機構７とで構成される。機械本体部２は、サドル３、リーダーマスト４、アーム５、クランプ６ａ、６ｂ、６ｃ、６ｄを備えている。アーム５は支柱１１を介してチャック機構７のシリンダ装置８と連結している。なお、リーダーマスト４とアーム５は固定されており、一体化してサドル３に対して方向Ｂに移動可能である。このため、チャック機構７で土留め用矢板１３を把持させてこれらを一体化してサドル３に対して方向Ｂに移動させることで、機械本体部２を方向Ｂに移動させることができる。さらに、土留め用矢板１３の地盤への圧入と機械本体部２の移動とを繰り返すことにより、圧入機１を方向Ｂに移動させることができる。 FIG. 1A shows an overall schematic diagram of the press-fitting machine 1.
The press-fitting machine 1 includes a machine body 2 and a chuck mechanism 7. The machine body 2 includes a saddle 3, a leader mast 4, an arm 5, clamps 6a, 6b, 6c, and 6d. The arm 5 is connected to the cylinder device 8 of the chuck mechanism 7 via the support 11. The leader mast 4 and the arm 5 are fixed, and can be moved in the direction B with respect to the saddle 3 as a unit. For this reason, the machine main body 2 can be moved in the direction B by gripping the earth retaining sheet pile 13 by the chuck mechanism 7 and integrating them to move in the direction B with respect to the saddle 3. Furthermore, the press-fitting machine 1 can be moved in the direction B by repeating the press-fitting of the earth retaining sheet pile 13 into the ground and the movement of the machine body 2.

チャック機構７は、シリンダ装置８、チャックフレーム９、土留め用矢板１３を把持可能な把持機構としてのチャック１０を備えている。また、支柱１１を介してシリンダ装置８は機械本体部２に連結しており、チャック機構７は土留め用矢板１３を把持したチャック１０を方向Ａに往復移動させることが可能である。すなわち、チャック機構７は移動機構としての役割を有している。 The chuck mechanism 7 includes a chuck 10 as a gripping mechanism capable of gripping the cylinder device 8, the chuck frame 9, and the earth retaining sheet pile 13. Further, the cylinder device 8 is connected to the machine main body 2 via the support column 11, and the chuck mechanism 7 can reciprocate the chuck 10 holding the earth retaining sheet pile 13 in the direction A. That is, the chuck mechanism 7 has a role as a moving mechanism.

圧入機１は、サドル３に設けられたクランプ６ａ、６ｂ、６ｃ、６ｄで既設の土留め用矢板１３を把持することで該土留め用矢板１３から反力を取って、該土留め用矢板１３に連結して新たな土留め用矢板１３を圧入して埋設する。次に、リーダーマスト４をサドル３に対して方向Ｂに移動させることで、埋設された土留め用矢板１３上を方向Ｂ１に土留め用矢板１３の１本分だけ移動する。次に、上記と同様の方法で既設の土留め用矢板１３から反力を取って、新たに土留め用矢板１３を地盤に圧入する。これらの動作を順次繰り返して土留め用矢板１３を順次圧入する。 The press-fitting machine 1 takes a reaction force from the earth retaining sheet pile 13 by gripping the existing earth retaining sheet pile 13 with clamps 6a, 6b, 6c, 6d provided on the saddle 3, and the earth retaining sheet pile 13 is pressed into a new earth retaining sheet pile 13 and buried. Next, by moving the leader mast 4 in the direction B with respect to the saddle 3, the leader mast 4 is moved in the direction B1 by one of the retaining sheet piles 13 in the direction B1. Next, a reaction force is taken from the existing earth retaining sheet pile 13 in the same manner as described above, and the earth retaining sheet pile 13 is newly press-fitted into the ground. These operations are sequentially repeated to sequentially press-fit the earth retaining sheet pile 13.

なお、土留め用矢板１３を地盤に圧入する際、土留め用矢板１３を把持したチャック１０を方向Ａに繰り返し往復移動させる。圧入機１において、その往復移動におけるチャック１０の移動可能距離は距離Ｌ１である。すなわち、圧入機１は、最大で距離Ｌ１まで、１回のチャック１０の往復移動（ストローク）で土留め用矢板１３を地盤に圧入することが可能である。 When the earth retaining sheet pile 13 is press-fitted into the ground, the chuck 10 holding the earth retaining sheet pile 13 is repeatedly reciprocated in the direction A. In the press-fitting machine 1, the movable distance of the chuck 10 in the reciprocating movement is a distance L1. That is, the press-fitting machine 1 can press-fit the earth retaining sheet pile 13 into the ground by one reciprocating movement (stroke) of the chuck 10 up to a distance L1.

本発明の土留め用矢板１３は、鋼矢板と易切削部材の矢板とを継手部材を用いて連結する土留め用矢板である。このような土留め用矢板を圧入機１で用いる場合、鋼矢板と易切削部材の矢板との連結部（継手部材を用いて連結された連結部）をチャック１０が把持できない場合がある。このため、該連結部をチャック１０が把持することなく土留め用矢板１３を地盤に圧入することが好ましい。このため、該連結部が１回のストロークでチャック１０を通過することができるように、前記継手部材における前記鋼矢板と前記易切削部材の矢板との連結方向の長さは、距離Ｌ１以下であることが好ましい。具体的な前記継手部材における前記鋼矢板と前記易切削部材の矢板との連結方向の長さは、５００ｍｍ以下が好ましい。 The earth retaining sheet pile 13 of the present invention is an earth retaining sheet pile that connects a steel sheet pile and an easily-cutting sheet pile using a joint member. When such a retaining sheet pile is used in the press-fitting machine 1, the chuck 10 may not be able to grip a connecting portion (a connecting portion connected using a joint member) between the steel sheet pile and the sheet pile of the easy-cutting member. For this reason, it is preferable to press-fit the earth retaining sheet pile 13 into the ground without the chuck 10 gripping the connecting portion. For this reason, the length of the connection direction of the steel sheet pile in the joint member and the sheet pile of the easy-cutting member is not more than a distance L1 so that the connection portion can pass the chuck 10 with one stroke. Preferably there is. As for the length of the connection direction of the steel sheet pile in the concrete joint member and the sheet pile of the easy-cutting member, 500 mm or less is preferred.

図１（Ｂ）は、チャック機構７の概要上面図を示している。
チャック１０には土留め用矢板１３を挿入して把持するための挿入穴１２が設けられている。圧入機１で使用可能な土留め用矢板１３は、その厚さが挿入穴１２の幅Ｗ（チャック１０が把持可能な厚さ）以下である必要がある。土留め用矢板１３に幅Ｗよりも厚い部分があると、該部分を挿入穴１２に挿入することができないためである。 FIG. 1B shows a schematic top view of the chuck mechanism 7.
The chuck 10 is provided with an insertion hole 12 for inserting and holding the earth retaining sheet pile 13. The retaining sheet pile 13 usable in the press-fitting machine 1 needs to have a thickness equal to or less than the width W of the insertion hole 12 (thickness that the chuck 10 can grip). This is because if the earth retaining sheet pile 13 has a portion thicker than the width W, the portion cannot be inserted into the insertion hole 12.

本発明の土留め用矢板１３は、鋼矢板と易切削部材の矢板とを継手部材を用いて連結する土留め用矢板である。このような土留め用矢板では、継手部材を用いて連結された連結部において、該継手部材と前記鋼矢板及び前記易切削部材の矢板との接触方向の厚さが最も厚くなる場合が多い。このため、該連結部の厚さは幅Ｗ以下であることが好ましい。具体的な連結部の厚さは５０ｍｍ以下であることが好ましい。 The earth retaining sheet pile 13 of the present invention is an earth retaining sheet pile that connects a steel sheet pile and an easily-cutting sheet pile using a joint member. In such earth retaining sheet piles, the thickness in the contact direction between the joint member, the steel sheet pile, and the sheet pile of the easy-cutting member is often the largest at the connecting portion connected using the joint member. For this reason, it is preferable that the thickness of this connection part is the width W or less. The specific thickness of the connecting portion is preferably 50 mm or less.

以下に、本発明の土留め用矢板１３の実施例を挙げながら具体的に説明する。
図２は、本発明の実施例１−３に係る土留め用矢板の要部概要図である。 Below, it demonstrates concretely, giving the Example of the sheet pile 13 for earth retaining of this invention.
FIG. 2: is a principal part schematic diagram of the sheet pile for earth retaining based on Example 1-3 of this invention.

［実施例１］
図２（Ａ）は、本発明の実施例１に係る土留め用矢板１３の要部概要図であり、鋼矢板１５と易切削部材の矢板１６との連結部１４を表す図である。
本実施例の連結部１４は鋼矢板１５と易切削部材の矢板１６とを継手部材１９ａ、１９ｂで両側から挟んで接合している。しかし、本発明の土留め用矢板はこのような構成に限定されず、鋼矢板及び易切削部材の矢板に対して継手部材を片側から接合する構成であってもよい。 [Example 1]
FIG. 2 (A) is a schematic view of the main part of the retaining sheet pile 13 according to the first embodiment of the present invention, and shows a connecting portion 14 between the steel sheet pile 15 and the sheet pile 16 of the easily cut member.
The connecting part 14 of the present embodiment joins a steel sheet pile 15 and a sheet pile 16 that is an easily cut member by sandwiching them from both sides with joint members 19a and 19b. However, the earth retaining sheet pile of the present invention is not limited to such a configuration, and may be a configuration in which the joint member is joined to the sheet pile of the steel sheet pile and the easy-cutting member from one side.

鋼矢板１５は、溶接により、継手部材１９ａ、１９ｂと接合されている。また、易切削部材の矢板１６は、ネジ山を備えたボルト１７及びボルト１７の両端に嵌合したナット１８により、継手部材１９ａ、１９ｂと接合されている。 The steel sheet pile 15 is joined to the joint members 19a and 19b by welding. Further, the sheet pile 16 of the easy-cutting member is joined to the joint members 19a and 19b by a bolt 17 having a thread and a nut 18 fitted to both ends of the bolt 17.

易切削部材の矢板１６は、鋼矢板１５よりも柔軟性には優れるが強度は低い。このため、易切削部材の矢板１６を鋼矢板１５と同様の強度（曲げ剛性等）にするためには、易切削部材の矢板１６の厚さＴ２を鋼矢板１５の厚さＴ１よりも厚くする必要がある。具体的には、易切削部材の矢板１６の曲げ剛性（曲げ弾性率と矢板１枚当たりの断面二次モーメントとの積）が鋼矢板１５の曲げ剛性に対して２５％以上になる厚さにすることが好ましい。なお、本実施例の鋼矢板１５と易切削部材の矢板１６の連結方向における幅は同様である。 The easy-cutting sheet pile 16 is more flexible than the steel sheet pile 15 but has a lower strength. For this reason, in order to make the sheet pile 16 of the easy-cutting member the same strength (bending rigidity etc.) as the steel sheet pile 15, the thickness T2 of the sheet pile 16 of the easy-cutting member is made thicker than the thickness T1 of the steel sheet pile 15. There is a need. Specifically, the thickness is such that the bending stiffness (the product of the bending elastic modulus and the cross-sectional second moment per sheet pile) of the sheet pile 16 of the easy-cutting member is 25% or more with respect to the bending stiffness of the steel sheet pile 15. It is preferable to do. In addition, the width | variety in the connection direction of the steel sheet pile 15 of a present Example and the sheet pile 16 of an easily cut member is the same.

また、易切削部材の矢板１６の材料は、高い強度と優れた切削性とを両立するため、繊維強化プラスチックであることが好ましい。特に、ガラス繊維及び炭素繊維の少なくとも一方或いは両方を合計で３０質量％以上含有する繊維強化プラスチックであることが好ましい。さらに、曲げ強度の観点から、ガラス繊維及び炭素繊維の少なくとも一方或いは両方を合計で４０質量％以上含有する繊維強化プラスチックであることが好ましい。 The material of the sheet pile 16 of the easy-cutting member is preferably a fiber reinforced plastic in order to achieve both high strength and excellent machinability. In particular, it is preferably a fiber reinforced plastic containing 30% by mass or more of at least one or both of glass fiber and carbon fiber. Furthermore, it is preferable that it is a fiber reinforced plastic which contains 40 mass% or more in total of at least one or both of glass fiber and carbon fiber from a viewpoint of bending strength.

本実施例における易切削部材の矢板１６は、ガラス繊維及び炭素繊維の合計含有量は５０質量％である。また、厚さＴ２は２３ｍｍ、曲げ弾性率は３２０００Ｎ／ｍｍ^２、断面二次モーメントは矢板１枚当たり５０４０ｃｍ^４であった。また、本実施例における鋼矢板１５は、厚さＴ２は１３ｍｍ、曲げ弾性率は２０００００Ｎ／ｍｍ^２、断面二次モーメントは矢板１枚当たり２２２０ｃｍ^４であった。すなわち、易切削部材の矢板１６の曲げ剛性は鋼矢板１５の曲げ剛性に対して３６％であった。また、継手部材１９ａ、１９ｂは厚さが６ｍｍ及び９ｍｍで構成されるものを用いた。 As for the sheet pile 16 of the easy-cutting member in a present Example, the total content of glass fiber and carbon fiber is 50 mass%. The thickness T2 was 23 mm, the flexural modulus was 32000 N / mm ² , and the cross-sectional secondary moment was 5040 cm ⁴ per sheet pile. In addition, the steel sheet pile 15 in this example had a thickness T2 of 13 mm, a flexural modulus of 200000 N / mm ² , and a sectional moment of 2220 cm ⁴ per sheet pile. That is, the bending rigidity of the sheet pile 16 of the easy-cutting member was 36% with respect to the bending rigidity of the steel sheet pile 15. In addition, the joint members 19a and 19b were configured with thicknesses of 6 mm and 9 mm.

また、連結部１４の強度は矢板部分（鋼矢板１５及び易切削部材の矢板１６）よりも強度が低くなる場合が多い。このため、連結部１４における継手部材１９ａ、１９ｂと鋼矢板１５及び易切削部材の矢板１６との接触方向の厚さＴ３と、継手部材１９ａ、１９ｂにおける鋼矢板１５と易切削部材の矢板１６との連結方向の長さＬ２とは、強度の観点から決定されることが好ましい。具体的には、連結部１４の曲げ破壊荷重が易切削部材の矢板１６の曲げ破壊荷重の０．６倍以上となるように、厚さＴ３と長さＬ２とは決定されることが好ましい。本実施例の易切削部材の矢板１６の曲げ破壊荷重は、２０５．５ｋＮであり、鋼矢板１５の公称曲げ破壊荷重の１００％以上であった。 Moreover, the strength of the connecting portion 14 is often lower than that of the sheet pile portion (the steel sheet pile 15 and the sheet pile 16 of the easy-cutting member). For this reason, the thickness T3 in the contact direction between the joint members 19a and 19b and the steel sheet pile 15 and the sheet pile 16 of the easy-cutting member in the connecting portion 14, and the steel sheet pile 15 and the sheet pile 16 of the easy-cut member and the joint members 19a and 19b The length L2 in the connecting direction is preferably determined from the viewpoint of strength. Specifically, it is preferable that the thickness T3 and the length L2 are determined so that the bending fracture load of the connecting portion 14 is 0.6 times or more the bending fracture load of the sheet pile 16 of the easily cut member. The bending fracture load of the sheet pile 16 of the easy-cutting member of this example was 205.5 kN, which was 100% or more of the nominal bending fracture load of the steel sheet pile 15.

なお、把持機構の把持可能厚さ及び往復移動可能距離は、鋼矢板の中でも特に使用頻度の多いＵ型鋼矢板を使用するほとんどの汎用の圧入機において共通化されている。本発明の土留め用矢板１３は、このような汎用の圧入機で使用可能であることが好ましい。このため、厚さＴ３は５０ｍｍ以下、長さＬ２は５００ｍｍ以下であることが好ましい。 The grippable thickness and the reciprocable distance of the gripping mechanism are common to most general-purpose press-fitting machines using U-shaped steel sheet piles that are frequently used among steel sheet piles. It is preferable that the earth retaining sheet pile 13 of the present invention can be used with such a general-purpose press-fitting machine. For this reason, it is preferable that the thickness T3 is 50 mm or less and the length L2 is 500 mm or less.

また、本実施例の土留め用矢板１３は、継手部材１９ａ、１９ｂと鋼矢板１５とは溶接により接合され、継手部材１９ａ、１９ｂと易切削部材の矢板１６とは接合部材としてのボルト１７及びナット１８を用いて接合されている。ここで、継手部材１９ａ、１９ｂと易切削部材の矢板１６との接合部の長さＬ４は、継手部材１９ａ、１９ｂと鋼矢板１５との接合部の長さＬ３よりも長い。別の表現をすると、継手部材１９ａ、１９ｂと易切削部材の矢板１６との接触面Ｓｂ１、Ｓｂ２の合計の面積は、継手部材１９ａ、１９ｂと鋼矢板１５との接触面Ｓａ１、Ｓａ２の合計の面積よりも大きい。このような構成としているのは、連結部１４の強度を高めるためである。 In addition, in the earth retaining sheet pile 13 of this embodiment, the joint members 19a, 19b and the steel sheet pile 15 are joined by welding, and the joint members 19a, 19b and the sheet pile 16 of the easy-cutting member are the bolt 17 and the joining member. It is joined using a nut 18. Here, the length L4 of the joint between the joint members 19a, 19b and the sheet pile 16 of the easy-cutting member is longer than the length L3 of the joint between the joint members 19a, 19b and the steel sheet pile 15. In other words, the total area of the contact surfaces Sb1 and Sb2 between the joint members 19a and 19b and the sheet pile 16 of the easy-cutting member is the sum of the contact surfaces Sa1 and Sa2 between the joint members 19a and 19b and the steel sheet pile 15. Greater than area. The reason for this configuration is to increase the strength of the connecting portion 14.

継手部材１９ａ、１９ｂと鋼矢板１５とは溶接により接合されていることで強固に接合される。継手部材１９ａ、１９ｂと易切削部材の矢板１６とは、連結方向に長く広い接触面で接合されていることで強固に接合される。特に、該接触面を連結方向に長くとることで、鋼矢板１５と接合する側の端部から鋼矢板１５と接合する側のボルト１７までの長さである切り裂き長さＬ５を長くすることができる。切り裂き長さＬ５を長くすることで連結部１４の強度を高くすることが可能になる。 The joint members 19a and 19b and the steel sheet pile 15 are joined firmly by welding. The joint members 19a and 19b and the sheet pile 16 of the easy-cutting member are firmly joined by being joined with a long and wide contact surface in the connecting direction. In particular, by making the contact surface long in the connecting direction, it is possible to increase the tearing length L5, which is the length from the end on the side where the steel sheet pile 15 is joined to the bolt 17 on the side where the steel sheet pile 15 is joined. it can. By increasing the tear length L5, the strength of the connecting portion 14 can be increased.

また、本実施例の継手部材１９ｂは、易切削部材の矢板１６の厚さと鋼矢板１５の厚さとの差に対応した切欠き深さの切欠き部を易切削部材の矢板１６と接触する側に有している。また、易切削部材の矢板１６は、該切欠き部に接合されている。連結部１４をこのような構成とすることで、連結部１４の強度を高く維持し、連結部１４の厚さＴ３を薄くすることが可能である。別の表現をすると、継手部材１９ａ、１９ｂと易切削部材の矢板１６との接合部の厚さが継手部材１９ａ、１９ｂと鋼矢板１５との接合部の厚さよりも厚い形状ではなくなり、連結部１４全体の厚さを薄くすることができている。 Further, the joint member 19b of the present embodiment is such that the notch portion of the notch depth corresponding to the difference between the thickness of the sheet pile 16 of the easy-cutting member and the thickness of the steel sheet pile 15 is in contact with the sheet pile 16 of the easy-cutting member. Have. Moreover, the sheet pile 16 of the easy-cutting member is joined to the notch. By configuring the connecting portion 14 as described above, the strength of the connecting portion 14 can be maintained high, and the thickness T3 of the connecting portion 14 can be reduced. In other words, the thickness of the joint between the joint members 19a, 19b and the sheet pile 16 of the easy-cutting member is not thicker than the thickness of the joint between the joint members 19a, 19b and the steel sheet pile 15, and the connecting portion The overall thickness of 14 can be reduced.

次に、本実施例の土留め用矢板１３における接合部材について説明する。
図３は、本発明の実施例１に係る土留め用矢板の接続部１４の拡大図である。
本実施例の土留め用矢板１３は、継手部材１９ａ、１９ｂ及び易切削部材の矢板１６とボルト１７との隙間を充填部材Ｅが充填されている。このため、継手部材１９ａ、１９ｂ及び易切削部材の矢板１６とボルトとの隙間がなくなっている。本実施例の土留め用矢板１３は、該隙間がないため、土留め用矢板１３が外部から力を受けた場合でも、接合間のすべりやズレ等が発生しにくく接合強度が高くなる。また、該隙間がないため、そこから土や水等が侵入せず、安全に掘削作業をすることが可能となる。 Next, the joining member in the sheet pile 13 for earth retaining of a present Example is demonstrated.
FIG. 3 is an enlarged view of the connection portion 14 of the earth retaining sheet pile according to the first embodiment of the present invention.
The earth retaining sheet pile 13 of the present embodiment is filled with a filling member E in the gaps between the joint members 19a and 19b and the sheet pile 16 and bolts 17 of the easy-cutting member. For this reason, the clearance gap between the coupling members 19a and 19b and the sheet pile 16 of the easy-cutting member and the bolt is eliminated. Since the earth retaining sheet pile 13 of this embodiment does not have the gap, even when the earth retaining sheet pile 13 receives a force from the outside, slippage or displacement between the joints hardly occurs and the joint strength is increased. Further, since there is no gap, soil and water do not enter from there, and it is possible to perform excavation work safely.

本実施例の充填部材Ｅは、管状の金属製部材である。ただし、本発明はこのような構成に限定されず、充填部材Ｅとして、管状の樹脂製部材或いは液状の樹脂をボルトとの隙間に充填して固化させたものなども使用できる。また、このような充填部材を継手部材１９ａ、１９ｂ及び易切削部材の矢板１６とボルトとの隙間に充填しないものも本発明に含まれる。 The filling member E of the present embodiment is a tubular metal member. However, the present invention is not limited to such a configuration, and as the filling member E, a tubular resin member or a liquid resin filled in a gap with a bolt and solidified can be used. Moreover, what does not fill such a filling member in the clearance gap between the joint members 19a and 19b and the sheet pile 16 of an easy-cutting member and a volt | bolt is also included in this invention.

なお、本実施例の土留め用矢板１３は、継手部材１９ａ、１９ｂと易切削部材の矢板１６とは接合部材としてボルト１７及びナット１８を用いている。しかし、本発明の土留め用矢板１３は、これらと共に又はこれらとは別に、継手部材１９ａ、１９ｂと易切削部材の矢板１６との間に接着剤を充填して接合することも可能である。また、本実施例のボルト１７はネジ山を備えた軸部のみからなる形状のボルトであるが、このようなボルトに限定されない。ネジ山を備えた軸部と頭部とからなるボルトでもよく、ボルトの頭部の形状も限定されない。 In addition, the earth retaining sheet pile 13 of the present embodiment uses bolts 17 and nuts 18 as joint members between the joint members 19a and 19b and the sheet pile 16 of the easily cut member. However, the earth retaining sheet pile 13 of the present invention can be joined together by filling an adhesive between the joint members 19a, 19b and the sheet pile 16 of the easy-cutting member together or separately. Moreover, although the volt | bolt 17 of a present Example is a volt | bolt of the shape which consists only of an axial part provided with the thread, it is not limited to such a volt | bolt. A bolt including a shaft portion and a head provided with a thread may be used, and the shape of the head of the bolt is not limited.

［実施例２］
図２（Ｂ）は、本発明の実施例２に係る土留め用矢板１３の要部概要図であり、鋼矢板１５と易切削部材の矢板１６との連結部１４を表す図である。なお、実施例１の土留め用矢板と共通する部材には同じ符号で示しており、その詳細な説明は省略する。
本実施例の土留め用矢板１３は、易切削部材の矢板１６と継手部材１９ｂとの接合部において、ナット１８を使用せずボルト１７のみを用いて接合されていることが実施例１の土留め用矢板１３と異なっている。土留め用矢板１３の連結部１４をこのような構成とすることで、連結部１４の強度を実施例１の連結部と同様に高く維持し、連結部１４の厚さＴ４を実施例１の連結部の厚さＴ３よりも薄くすることが可能である。 [Example 2]
FIG. 2 (B) is a schematic diagram of a main part of the earth retaining sheet pile 13 according to the second embodiment of the present invention, and is a diagram illustrating a connecting portion 14 between the steel sheet pile 15 and the sheet pile 16 of the easily cut member. In addition, the same code | symbol is shown to the member which is common in the sheet pile for earth retaining of Example 1, The detailed description is abbreviate | omitted.
The earth retaining sheet pile 13 of this embodiment is joined by using only the bolt 17 without using the nut 18 at the joint portion between the sheet pile 16 of the easy-cutting member and the joint member 19b. Different from the fastening sheet pile 13. By configuring the connecting portion 14 of the earth retaining sheet pile 13 as described above, the strength of the connecting portion 14 is maintained high as in the connecting portion of the first embodiment, and the thickness T4 of the connecting portion 14 is set to that of the first embodiment. It is possible to make it thinner than the thickness T3 of the connecting portion.

［実施例３］
図２（Ｃ）は、本発明の実施例３に係る土留め用矢板１３の要部概要図であり、鋼矢板１５と易切削部材の矢板１６との連結部１４を表す図である。なお、実施例１、２の土留め用矢板と共通する部材には同じ符号で示しており、その詳細な説明は省略する。
本実施例の土留め用矢板１３は、易切削部材の矢板１６と継手部材１９ａ、１９ｂの両方との接合部において、ナット１８を使用せずボルト１７のみを用いて接合されていることが実施例１及び実施例２の土留め用矢板１３と異なっている。土留め用矢板１３の連結部１４をこのような構成とすることで、連結部１４の強度を実施例１及び実施例２の連結部と同様に高く維持し、連結部１４の厚さＴ５を実施例２の連結部の厚さＴ４よりもさらに薄くすることが可能である。 [Example 3]
FIG.2 (C) is a principal part schematic diagram of the earth retaining sheet pile 13 which concerns on Example 3 of this invention, and is a figure showing the connection part 14 of the steel sheet pile 15 and the sheet pile 16 of an easy-cutting member. In addition, the same code | symbol is shown to the member which is common with the sheet pile for earth retaining of Example 1, 2, and the detailed description is abbreviate | omitted.
In this embodiment, the earth retaining sheet pile 13 is joined by using only the bolt 17 without using the nut 18 at the joint portion between both the sheet pile 16 of the easy-cutting member and the joint members 19a and 19b. This is different from the earth retaining sheet pile 13 of Example 1 and Example 2. By configuring the connecting portion 14 of the earth retaining sheet pile 13 as described above, the strength of the connecting portion 14 is maintained high as in the connecting portions of the first and second embodiments, and the thickness T5 of the connecting portion 14 is set to be high. It is possible to make it thinner than the thickness T4 of the connecting portion of the second embodiment.

［実施例４］
図４（Ａ）は、本発明の実施例４に係る土留め用矢板１３の要部概要図であり、鋼矢板１５と易切削部材の矢板１６との連結部１４を表す図である。なお、実施例１〜３の土留め用矢板と共通する部材には同じ符号で示しており、その詳細な説明は省略する。
本実施例の土留め用矢板１３の易切削部材の矢板１６は、易切削部材の矢板１６の厚さＴ３と鋼矢板１５の厚さＴ１との差に対応した切欠き深さの切欠き部を鋼矢板１５と連結する側に有している。そして、接合部材１９ｃは、該切欠き部に接合されている。連結部１４をこのような構成とすることで、連結部１４の強度を高く維持し、連結部１４の厚さＴ６を実施例１の連結部の厚さＴ３よりも薄くすることが可能である。 [Example 4]
FIG. 4 (A) is a schematic diagram of a main part of a sheet pile 13 for retaining according to a fourth embodiment of the present invention, and is a diagram showing a connecting portion 14 between a steel sheet pile 15 and a sheet pile 16 of an easily cut member. In addition, the same code | symbol is shown to the member which is common in the sheet pile for earth retaining of Examples 1-3, The detailed description is abbreviate | omitted.
The sheet pile 16 of the easy-cutting member of the earth retaining sheet pile 13 of the present embodiment is a notch portion having a notch depth corresponding to the difference between the thickness T3 of the sheet pile 16 of the easy-cutting member and the thickness T1 of the steel sheet pile 15. On the side connected to the steel sheet pile 15. The joining member 19c is joined to the notch. By configuring the connecting portion 14 as described above, the strength of the connecting portion 14 can be maintained high, and the thickness T6 of the connecting portion 14 can be made thinner than the thickness T3 of the connecting portion of the first embodiment. .

［実施例５］
図４（Ｂ）は、本発明の実施例５に係る土留め用矢板１３の要部概要図であり、鋼矢板１５と易切削部材の矢板１６との連結部１４を表す図である。なお、実施例１〜４の土留め用矢板と共通する部材には同じ符号で示しており、その詳細な説明は省略する。
本実施例の土留め用矢板１３は、易切削部材の矢板１６と継手部材１９ｃとの接合部において、ナット１８を使用せずボルト１７のみを用いて接合されていることが実施例４の土留め用矢板１３と異なっている。土留め用矢板１３の連結部１４をこのような構成とすることで、連結部１４の強度を実施例４の連結部と同様に高く維持し、連結部１４の厚さＴ７を実施例４の連結部の厚さＴ６よりも薄くすることが可能である。 [Example 5]
FIG. 4B is a schematic view of the main part of the sheet pile 13 for retaining according to the fifth embodiment of the present invention, and is a view showing the connecting portion 14 between the steel sheet pile 15 and the sheet pile 16 of the easily cut member. In addition, the same code | symbol is shown to the member which is common in the sheet pile for earth retaining of Examples 1-4, The detailed description is abbreviate | omitted.
The earth retaining sheet pile 13 of the present embodiment is joined by using only the bolt 17 without using the nut 18 at the joint portion between the sheet pile 16 of the easy-cutting member and the joint member 19c. Different from the fastening sheet pile 13. By configuring the connecting portion 14 of the earth retaining sheet pile 13 as described above, the strength of the connecting portion 14 is maintained high similarly to the connecting portion of the fourth embodiment, and the thickness T7 of the connecting portion 14 is set to that of the fourth embodiment. It is possible to make it thinner than the thickness T6 of the connecting portion.

［実施例６］
図４（Ｃ）は、本発明の実施例６に係る土留め用矢板１３の要部概要図であり、鋼矢板１５と易切削部材の矢板１６との連結部１４を表す図である。なお、実施例１〜５の土留め用矢板と共通する部材には同じ符号で示しており、その詳細な説明は省略する。
本実施例の土留め用矢板１３は、易切削部材の矢板１６と継手部材１９ａ、１９ｃの両方との接合部において、ナット１８を使用せずボルト１７のみを用いて接合されていることが実施例４及び実施例５の土留め用矢板１３と異なっている。土留め用矢板１３の連結部１４をこのような構成とすることで、連結部１４の強度を実施例４及び実施例５の連結部と同様に高く維持し、連結部１４の厚さＴ８を実施例５の連結部の厚さＴ７よりもさらに薄くすることが可能である。 [Example 6]
FIG.4 (C) is a principal part schematic diagram of the earth retaining sheet pile 13 which concerns on Example 6 of this invention, and is a figure showing the connection part 14 of the steel sheet pile 15 and the sheet pile 16 of an easy-cutting member. In addition, the same code | symbol is shown to the member which is common with the sheet pile for Example 1-5, and the detailed description is abbreviate | omitted.
The earth retaining sheet pile 13 of the present embodiment is joined by using only the bolt 17 without using the nut 18 in the joint portion between the sheet pile 16 of the easy-cutting member and the joint members 19a and 19c. It differs from the sheet pile 13 for earth retaining of Example 4 and Example 5. By configuring the connecting portion 14 of the earth retaining sheet pile 13 as described above, the strength of the connecting portion 14 is maintained high as in the connecting portions of the fourth and fifth embodiments, and the thickness T8 of the connecting portion 14 is set to be high. It is possible to make it thinner than the thickness T7 of the connecting portion of the fifth embodiment.

［実施例７］
図５は、本発明の実施例７に係る土留め用矢板１３の要部概要図であり、易切削部材の矢板１６における鋼矢板１５と連結する側と逆側（地盤に圧入する側）の端部２２を表す図である。なお、実施例１〜６の土留め用矢板と共通する部材には同じ符号で示しており、その詳細な説明は省略する。
図５（Ａ）は、本実施例の土留め用矢板１３における易切削部材の矢板１６の地盤に圧入する側の端部２２の側面図である。また、図５（Ｂ）は本実施例の土留め用矢板１３における易切削部材の矢板１６の地盤に圧入する側の端部２２の正面図である。 [Example 7]
FIG. 5: is a principal part schematic diagram of the sheet pile 13 for earth retaining which concerns on Example 7 of this invention, and is the opposite side (side press-fitted into the ground) with the side connected with the steel sheet pile 15 in the sheet pile 16 of an easily cut member. It is a figure showing the edge part 22. FIG. In addition, the same code | symbol is shown to the member which is common with the sheet pile for earth retaining of Examples 1-6, The detailed description is abbreviate | omitted.
FIG. 5A is a side view of the end 22 on the side to be press-fitted into the ground of the sheet pile 16 of the easy-cutting member in the retaining sheet pile 13 of the present embodiment. FIG. 5B is a front view of the end 22 on the side to be press-fitted into the ground of the sheet pile 16 of the easy-cutting member of the earth retaining sheet pile 13 of the present embodiment.

本実施例の土留め用矢板１３は、易切削部材の矢板１６の地盤に圧入する側の端部２２に、易切削部材の矢板１６を保護する保護カバー２０を備えている。保護カバー２０の先端部には刃先２１が設けられ、刃先２１を地盤に当接して土留め用矢板１３を圧入する。なお、１枚の土留め用矢板１３に２組の保護カバー２０が備えられ、保護カバー２０は夫々４組のボルト１７及びナット１８を用いて易切削部材の矢板１６に接合されている。土留め用矢板１３の地盤に当接する側の先端にこのような保護カバー２０を備えることで、易切削部材の矢板１６の保護だけでなく土留め用矢板１３の圧入を容易にする。このため、このような保護カバー２０を土留め用矢板１３の地盤に当接する側の先端に備えることは好ましいが、本発明はこのような構成に限定されるわけではなく、保護カバーを備えない土留め用矢板１３も本発明に含まれる。 The earth retaining sheet pile 13 of the present embodiment includes a protective cover 20 that protects the sheet pile 16 of the easy-cutting member at the end 22 on the side that is press-fitted into the ground of the sheet pile 16 of the easy-cutting member. A blade edge 21 is provided at the tip of the protective cover 20, and the earth retaining sheet pile 13 is press-fitted by bringing the blade edge 21 into contact with the ground. In addition, two sets of protective covers 20 are provided on one sheet pile for retaining earth 13, and the protective covers 20 are joined to the sheet piles 16 of easy-to-cut members using four sets of bolts 17 and nuts 18 respectively. By providing such a protective cover 20 at the tip of the earth retaining sheet pile 13 in contact with the ground, not only protection of the sheet pile 16 of the easy-cutting member but also the press fitting of the earth retaining sheet pile 13 is facilitated. For this reason, although it is preferable to provide such a protective cover 20 at the tip of the earth retaining sheet pile 13 that contacts the ground, the present invention is not limited to such a configuration and does not include a protective cover. The earth retaining sheet pile 13 is also included in the present invention.

本実施例の土留め用矢板１３に備えられた保護カバー２０における地盤への圧入方向（縦方向）の長さＬ６及び２組の保護カバー２０が並ぶ方向（横方向）の長さＬ７は共に１００ｍｍ以下であることが好ましい。土留め用矢板１３が地盤へ圧入された後に保護カバー２０を回収する際、シールドマシンの排泥管を通して回収可能にするためである。 Both the length L6 in the press-fitting direction (vertical direction) to the ground and the length L7 in the direction in which the two sets of protective covers 20 are arranged (lateral direction) in the protective cover 20 provided in the earth retaining sheet pile 13 of this embodiment are both. It is preferable that it is 100 mm or less. This is because when the protective cover 20 is recovered after the earth retaining sheet pile 13 is pressed into the ground, it can be recovered through the sludge pipe of the shield machine.

［実施例８］
図６は、本発明の実施例８に係る土留め用矢板１３の要部概要図であり、易切削部材の矢板１６における地盤に圧入する側の端部２２を表す図である。なお、実施例１〜７の土留め用矢板と共通する部材には同じ符号で示しており、その詳細な説明は省略する。
図６（Ａ）は、本実施例の土留め用矢板１３における易切削部材の矢板１６の地盤に圧入する側の端部２２の側面図である。また、図６（Ｂ）は本実施例の土留め用矢板１３における易切削部材の矢板１６の地盤に圧入する側の端部２２の正面図である。 [Example 8]
FIG. 6: is a principal part schematic diagram of the earth retaining sheet pile 13 which concerns on Example 8 of this invention, and is a figure showing the edge part 22 by the side press-fitted in the ground in the sheet pile 16 of an easy-cutting member. In addition, the same code | symbol is shown to the member which is common in the sheet pile for earth retaining of Examples 1-7, The detailed description is abbreviate | omitted.
FIG. 6A is a side view of the end 22 on the side to be press-fitted into the ground of the sheet pile 16 of the easy-cutting member in the earth retaining sheet pile 13 of the present embodiment. FIG. 6B is a front view of the end 22 on the side to be press-fitted into the ground of the sheet pile 16 of the easy-cutting member in the earth retaining sheet pile 13 of the present embodiment.

本実施例の土留め用矢板１３と実施例７の土留め用矢板１３との違いは、本実施例の土留め用矢板１３の端部２２に、緩衝材２３が設けられているところである。本実施例の土留め用矢板１３は、保護カバー２０の刃先２１と易切削部材の矢板１６の地盤に圧入する側の先端部との間に緩衝材２３を設けている。このことで、土留め用矢板１３を地盤へ圧入する際の易切削部材の矢板１６の保護効果は実施例７の土留め用矢板１３よりも高くなっている。
なお、本実施例の保護カバー２０の縦方向の長さＬ８は、実施例７の保護カバー２０の縦方向の長さＬ６と同様であり、本実施例の保護カバー２０の横方向の長さＬ９は、実施例７の保護カバー２０の横方向の長さＬ７と同様である。 The difference between the retaining sheet pile 13 of the present embodiment and the retaining sheet pile 13 of the seventh embodiment is that a cushioning material 23 is provided at the end 22 of the retaining sheet pile 13 of the present embodiment. The earth retaining sheet pile 13 of the present embodiment is provided with a cushioning material 23 between the cutting edge 21 of the protective cover 20 and the front end portion of the easy cutting member on the side press-fitted into the ground. Thereby, the protective effect of the sheet pile 16 of the easily cut member when the sheet pile sheet pile 13 is press-fitted into the ground is higher than the sheet pile sheet pile 13 of the seventh embodiment.
The vertical length L8 of the protective cover 20 of the present embodiment is the same as the vertical length L6 of the protective cover 20 of the seventh embodiment, and the horizontal length of the protective cover 20 of the present embodiment. L9 is the same as the lateral length L7 of the protective cover 20 of the seventh embodiment.

［実施例９］
図７（Ａ）は、本発明の実施例９に係る土留め用矢板１３の要部概要図であり、易切削部材の矢板１６と継手部材１９ｅ、１９ｆ、１９ｇ、１９ｈとの接合部を表す横断面図である。なお、実施例１〜８の土留め用矢板と共通する部材には同じ符号で示しており、その詳細な説明は省略する。
本実施例の易切削部材の矢板１６はＵ型の矢板であり、Ｕ型の鋼矢板１５と３ヶ所で連結されている。詳細には、継手部材１９ｅ、１９ｆにより２カ所で、継手部材１９ｇ、１９ｈにより１カ所で連結されている。 [Example 9]
FIG. 7 (A) is a schematic diagram of the main part of the sheet pile 13 for earth retaining according to the ninth embodiment of the present invention, and represents a joint portion between the sheet pile 16 of the easy-cutting member and the joint members 19e, 19f, 19g, and 19h. It is a cross-sectional view. In addition, the same code | symbol is shown to the member which is common in the sheet pile for earth retaining of Examples 1-8, The detailed description is abbreviate | omitted.
The easy-cutting sheet pile 16 of this embodiment is a U-shaped sheet pile, and is connected to the U-shaped steel sheet pile 15 at three locations. Specifically, the joint members 19e and 19f are connected at two places and the joint members 19g and 19h are connected at one place.

［実施例１０］
図７（Ｂ）は、本発明の実施例１０に係る土留め用矢板１３の要部概要図であり、易切削部材の矢板１６と継手部材１９ｉ、１９ｊとの接合部を表す横断面図である。なお、実施例１〜９の土留め用矢板と共通する部材には同じ符号で示しており、その詳細な説明は省略する。
本実施例の易切削部材の矢板１６はＵ型の矢板であり、Ｕ型の鋼矢板１５と継手部材１９ｉ、１９ｊで連結されている。継手部材１９ｉ、１９ｊは、Ｕ型の易切削部材の矢板１６及びＵ型の鋼矢板１５と隙間なく接合するようＵ型の形状をしている。 [Example 10]
FIG. 7B is a schematic diagram of the main part of the earth retaining sheet pile 13 according to the tenth embodiment of the present invention, and is a cross-sectional view showing the joint between the sheet pile 16 of the easy-cutting member and the joint members 19i, 19j. is there. In addition, the same code | symbol is shown to the member which is common with the sheet pile for earth retaining of Examples 1-9, The detailed description is abbreviate | omitted.
The easy-cutting sheet pile 16 of the present embodiment is a U-shaped sheet pile, and is connected to a U-shaped steel sheet pile 15 and joint members 19i and 19j. The joint members 19i, 19j are U-shaped so as to be joined to the sheet pile 16 of the U-shaped easy-cutting member and the U-shaped steel sheet pile 15 without a gap.

１圧入機、２機械本体部、３サドル、４リーダーマスト、５アーム、
６ａ，６ｂ，６ｃ，６ｄクランプ、７チャック機構、８シリンダ装置、
９チャックフレーム、１０チャック、１１支柱、１２挿入穴、
１３土留め用矢板、１４連結部、１５鋼矢板、１６易切削部材の矢板、
１７ボルト、１８ナット、１９ａ，１９ｂ，１９ｃ，１９ｄ継手部材、
１９ｅ，１９ｆ，１９ｇ，１９ｈ，１９ｉ，１９ｊ継手部材、
２０保護カバー、２１刃先、２２易切削部材の矢板１６の端部、２３緩衝材、
Ｅ封止剤、Ｌ１チャック１０の移動可能距離、
Ｌ２継手部材１９ａ、１９ｂの長さ、
Ｌ３継手部材１９ａ、１９ｂと鋼矢板１５との接合部の長さ、
Ｌ４継手部材１９ａ、１９ｂと易切削部材の矢板１６との接合部の長さ、
Ｌ５切り裂き長さ、
Ｌ６保護カバー２０の縦方向の長さ、Ｌ７保護カバー２０の横方向の長さ、
Ｌ８保護カバー２０の縦方向の長さ、Ｌ９保護カバー２０の横方向の長さ、
Ｓａ１継手部材１９ａ（１９ｃ）と鋼矢板１５との接触面、
Ｓａ２継手部材１９ｂ（１９ｄ）と鋼矢板１５との接触面、
Ｓｂ１継手部材１９ａ（１９ｃ）と易切削部材の矢板１６との接触面、
Ｓｂ２継手部材１９ｂ（１９ｄ）と易切削部材の矢板１６との接触面、
Ｔ１鋼矢板１５の厚さ、Ｔ２易切削部材の矢板１６の厚さ、
Ｔ３，Ｔ４，Ｔ５，Ｔ６，Ｔ７，Ｔ８連結部１４の厚さ、
Ｗ挿入穴１２の幅 1 press-fitting machine, 2 machine body, 3 saddle, 4 leader mast, 5 arm,
6a, 6b, 6c, 6d Clamp, 7 Chuck mechanism, 8 Cylinder device,
9 Chuck frame, 10 Chuck, 11 Post, 12 Insertion hole,
13 sheet pile for earth retaining, 14 connection part, 15 steel sheet pile, 16 sheet pile of easily cut member,
17 bolts, 18 nuts, 19a, 19b, 19c, 19d joint members,
19e, 19f, 19g, 19h, 19i, 19j joint member,
20 protective cover, 21 cutting edge, 22 end of sheet pile 16 of easy-cutting member, 23 cushioning material,
E Sealant, L1 Chuck 10 movable distance,
L2 length of the joint members 19a and 19b,
L3 length of the joint portion between the joint members 19a, 19b and the steel sheet pile 15,
L4 joint members 19a, 19b and the length of the joint between the easily cut member sheet pile 16,
L5 tear length,
L6 The length in the vertical direction of the protective cover 20, L7 The length in the horizontal direction of the protective cover 20,
L8 longitudinal length of the protective cover 20, L9 lateral length of the protective cover 20,
Sa1 contact surface between the joint member 19a (19c) and the steel sheet pile 15,
Sa2 contact surface between the joint member 19b (19d) and the steel sheet pile 15,
A contact surface between the Sb1 joint member 19a (19c) and the sheet pile 16 of the easy-cutting member;
Contact surface between the Sb2 joint member 19b (19d) and the sheet pile 16 of the easy-cut member,
T1 thickness of steel sheet pile 15, thickness of sheet pile 16 of T2 easy-cutting member,
T3, T4, T5, T6, T7, T8 The thickness of the connecting portion 14,
W Width of insertion hole 12

Claims

A steel sheet pile and an easy-cutting sheet pile connected to each other by a joint member,
In the surface along the connecting direction of the steel sheet pile and the sheet pile of the easy-cutting member, the joint member and the steel sheet pile are joined by welding,
In the surface along the connection direction, the joint member and the sheet pile of the easy-cutting member are joined using a joining member,
The length of the joint portion between the joint member and the sheet pile of the easy-cutting member in the connection direction between the steel sheet pile and the easy-cutting member sheet pile is that of the joint portion between the joint member and the steel sheet pile in the connection direction. Earth retaining sheet pile characterized by being longer than the length.

A steel sheet pile and an easy-cutting sheet pile connected to each other by a joint member,
The joint member and the steel sheet pile are joined by welding,
The joint member and the sheet pile of the easy-cutting member are joined using a joining member,
The earth retaining sheet pile is
It can be used in a press-fitting machine equipped with a gripping mechanism capable of gripping the earth retaining sheet pile and a moving mechanism capable of reciprocating the gripping mechanism,
The length in the coupling direction of the joint member is not more than a length corresponding to the reciprocable distance of the gripping mechanism by the moving mechanism , and is 500 mm or less,
The thickness in the contact direction of the joint member, the steel sheet pile, and the sheet pile of the easy-cutting member in the coupling portion coupled using the joint member is equal to or less than a thickness that can be gripped by the gripping mechanism, and is 50 mm. Earthing sheet pile characterized by the following.

A steel sheet pile and an easy-cutting sheet pile connected to each other by a joint member,
The joint member and the steel sheet pile are joined by welding,
The joint member and the sheet pile of the easy-cutting member are joined using a joining member,
The joining member includes a bolt and a filling member that fills a gap between the joint member and the sheet pile of the easy-cutting member and the bolt.

A steel sheet pile and an easy-cutting sheet pile connected to each other by a joint member,
The joint member and the steel sheet pile are joined by welding,
The joint member and the sheet pile of the easy-cutting member are joined using a joining member,
The thickness of the sheet pile of the easy-cutting member in the contact direction between the joint member, the steel sheet pile, and the sheet pile of the easy-cutting member is greater than the thickness of the steel sheet pile in the direction. .

In the sheet pile for earth retaining according to claim 4 ,
The joint member has a notch portion with a notch depth corresponding to the difference between the thickness of the sheet pile of the easy-cutting member and the thickness of the steel sheet pile on the side in contact with the sheet pile of the easy-cutting member;
The sheet pile for earth retaining, wherein the sheet pile of the easy-cutting member is joined to the notch.

In the sheet pile for earth retaining according to claim 4 ,
The sheet pile of the easy-cutting member has a notch portion with a notch depth corresponding to the difference between the thickness of the sheet pile of the easy-cutting member and the thickness of the steel sheet pile on the side connected to the steel sheet pile,
The sheet pile for earth retaining, wherein the joining member is joined to the notch.

A steel sheet pile and an easy-cutting sheet pile connected to each other by a joint member,
The joint member and the steel sheet pile are joined by welding,
The joint member and the sheet pile of the easy-cutting member are joined using a joining member,
Bending rigidity represented by the product of the bending elastic modulus of a sheet pile of the easy-cutting member and the cross-sectional second moment per sheet pile is 25% or more of the bending rigidity of a steel sheet pile. Sheet pile.

A steel sheet pile and an easy-cutting sheet pile connected to each other by a joint member,
The joint member and the steel sheet pile are joined by welding,
The joint member and the sheet pile of the easy-cutting member are joined using a joining member,
The material for the sheet pile of the easy-cutting member is a fiber reinforced plastic containing at least one or both of glass fiber and carbon fiber in a total amount of 30% by mass or more.

In the sheet pile for earth retaining according to any one of claims 1 to 7 ,
A material for a sheet pile of the easy-cutting member is a fiber reinforced plastic.