JP6010070B2 - Temporary closing method for existing underwater structures - Google Patents

Temporary closing method for existing underwater structures Download PDF

Info

Publication number
JP6010070B2
JP6010070B2 JP2014137541A JP2014137541A JP6010070B2 JP 6010070 B2 JP6010070 B2 JP 6010070B2 JP 2014137541 A JP2014137541 A JP 2014137541A JP 2014137541 A JP2014137541 A JP 2014137541A JP 6010070 B2 JP6010070 B2 JP 6010070B2
Authority
JP
Japan
Prior art keywords
temporary
bracket
underwater
cut
cutoff
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.)
Active
Application number
JP2014137541A
Other languages
Japanese (ja)
Other versions
JP2016014290A (en
Inventor
▲靖▼ 岩本
▲靖▼ 岩本
巳木男 日下
巳木男 日下
哲 戸澤
哲 戸澤
Original Assignee
オリエンタル白石株式会社
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 オリエンタル白石株式会社 filed Critical オリエンタル白石株式会社
Priority to JP2014137541A priority Critical patent/JP6010070B2/en
Publication of JP2016014290A publication Critical patent/JP2016014290A/en
Application granted granted Critical
Publication of JP6010070B2 publication Critical patent/JP6010070B2/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Description

本発明は、橋脚などの既設水中構造物の調査、補修、補強等の工事のために水中構造物の周りを鋼製パネル等で一旦締め切ってその内部を排水して本工事を行う既設水中構造物の仮締切り工法に関するものである。   The present invention is an existing underwater structure in which the work is carried out by temporarily closing the periphery of the underwater structure with a steel panel etc. and draining the inside of the underwater structure such as a bridge pier for investigation, repair, reinforcement, etc. This relates to the temporary cut-off method for objects.
従来、河川や海中に位置する橋脚などの既設水中構造物の調査、補修、補強等の工事を行うための仮設工事として、既設水中構造物の基礎の外側に台船などから鋼矢板を打ち込んで、その内側の水を汲み上げ排水するとともに、土砂を全部浚渫してドライな作業エリアを構築し、本工事が行われていた。   Conventionally, as a temporary work for surveying, repairing and reinforcing existing underwater structures such as river piers and underwater bridges, steel sheet piles have been driven from a baseboard or the like outside the foundation of existing underwater structures. In addition to drawing up the water inside and draining it, the work was carried out by constructing a dry work area by dripping all the earth and sand.
しかし、鋼矢板は幅が狭く、必然的に、打ち込み箇所が多くなる上、空頭制限が厳しい環境では、そもそも施工できないという問題があった。また、一旦使用した短尺の鋼矢板はスクラップ扱いになるため、不経済であるという問題もあった。さらに、施工時の河積阻害や船路確保が懸念される他、鋼矢板を打ち込み地盤が軟弱地盤である場合には、根入れ長さが深くなり、施工期間が長期化し、施工費が嵩むという問題もあった。   However, the steel sheet pile has a narrow width, which inevitably increases the number of places to be driven, and there is a problem that it cannot be constructed in an environment where there are severe restrictions on the empty head. Moreover, since the short steel sheet pile once used becomes scrap handling, there also existed a problem that it was uneconomical. Furthermore, there are concerns about river blockage and securing of the channel during construction, and if the ground is soft ground by driving steel sheet piles, the depth of rooting becomes deep, the construction period becomes longer, and construction costs increase. There was also a problem.
その他、鋼矢板を用いない仮締切工法としては、例えば、特許文献1には、橋脚1の外周を筒型仮締切壁14で囲撓し、内部を排水して、補強工事を行い、工事の終了後に仮締切壁14を撤去する仮締切り工法において、仮締切壁14は、周方向に沿って、鉛直方向に分断した複数のパネルユニット16に分割形成され、仮締切壁14を形成する際には、橋脚1のフーチング2部上にガイド枠10を設置し、各パネルユニット16の内面側を、ガイド枠10に係止するようにして、パネルユニット16を垂設支持した後に、パネルユニット16の下端側を、フーチング部2の外周に沿った水底地盤3中にコンクリート打設により止水固定し、かつ、周方向に隣接するパネルユニット16間に止水パッキンを介装して、水密性を確保しながら、パネルユニット16を周方向に連結して筒型形状に形成する仮締切り工法が開示されている(特許文献1の特許請求の範囲の請求項1、明細書の段落0018〜0042、図面の図1〜22等参照)。   In addition, as a temporary closing method without using a steel sheet pile, for example, in Patent Document 1, the outer periphery of the pier 1 is bent and bent by the cylindrical temporary cutting wall 14, the inside is drained, and the reinforcement work is performed. In the temporary closing method in which the temporary cutoff wall 14 is removed after completion, the temporary cutoff wall 14 is divided into a plurality of panel units 16 divided in the vertical direction along the circumferential direction, and the temporary cutoff wall 14 is formed. The guide frame 10 is installed on the footing 2 part of the pier 1 and the panel unit 16 is suspended and supported so that the inner surface side of each panel unit 16 is locked to the guide frame 10. Water-tightness is secured by fixing the water to the bottom ground 3 along the outer periphery of the footing part 2 by pouring concrete and interposing panel seals 16 between adjacent panel units 16 in the circumferential direction. While ensuring Disclosed is a temporary cut-off method in which the nell units 16 are connected in the circumferential direction to form a cylindrical shape (claim 1 of patent document 1, paragraphs 0018 to 0042 of the specification, FIG. 1 of the drawings). ˜22 etc.).
しかし、特許文献1に記載の仮締切り工法では、仮締切壁14を橋脚1のフーチング部2の外側に設置する関係上、事前に、埋没したフーチング部2の天端が露出するまで浚渫する必要があり、地盤によっては、水中土留め壁(鋼矢板)5を打ち込まなければならなかった。そのため、フーチング部2の天端までの土被りが深い場合は、鋼矢板を用いた従来工法と同様に、大規模浚渫に伴い、近隣構造物への悪影響や河川等の近隣環境の汚濁などの環境面の問題が懸念されるうえ、浚渫土処理の費用も嵩むといった問題があった。   However, in the temporary closing method described in Patent Document 1, because the temporary closing wall 14 is installed outside the footing portion 2 of the pier 1, it is necessary to make a dredge in advance until the top end of the buried footing portion 2 is exposed. Depending on the ground, it was necessary to drive an underwater earth retaining wall (steel sheet pile) 5. Therefore, when the earth covering to the top edge of the footing part 2 is deep, as with the conventional construction method using steel sheet piles, there are adverse effects on neighboring structures and pollution of neighboring environments such as rivers, etc. In addition to concerns about environmental issues, there was a problem that the cost of the dredging treatment increased.
また、本願の出願人が開発したものとして、特許文献2には、(1)水中の既設構造物に圧入反力手段を設置する工程と、(2)既設構造物の外周に複数に分割された締切り鋼板を周方向に連結して最下端の補強リング体を形成する工程と、(3)最下端の補強リング体の上に圧入桁、圧入ジャッキを設置し、最下端の補強リング体を圧入反力手段、圧入ジャッキ、ガイド部材を介して水底地盤中に圧入する工程と、(4)最下端の補強リング体で締切られた水底地盤を掘削する工程と、(5)圧入桁、圧入ジャッキを撤去し、次の補強リング体を組み立て、最下端の補強リング体の上部に2段目の補強リング体を連結する工程と、(6)2段目の補強リング体の上に圧入桁、圧入ジャッキを設置し、最下端の補強リング体と2段目の補強リング体を基礎中に圧入する工程と、(7)前記工程を繰返し、補強リング体を水底地盤の天端から水底地盤中の所望の深さまで圧入する工程と、(8)補強リング体上端から水面上まで伸びる締切り部材としてのリング状ライナープレート或いは鋼製リングを設置する工程と、(9)補強リング体とリング状ライナープレート或いは鋼製リングで囲繞されるスペース内で水底地盤の天端から所望深さまで掘削し、止水材を取付け、止水用コンクリートを打設し、仮締切り構造内の水を汲み出しドライな作業空間を形成する工程と、を有することを特徴とする水中の既設構造物の仮締切り工法が開示されている(特許文献2の特許請求の範囲の請求項7、明細書の段落0016、図面の図3等参照)。   Further, as developed by the applicant of the present application, Patent Document 2 includes (1) a step of installing a press-fitting reaction force means on an existing structure in water, and (2) a plurality of divisions on the outer periphery of the existing structure. Connecting the cut-off steel plates in the circumferential direction to form a lowermost reinforcing ring body, and (3) installing a press-fitting girder and a press-in jack on the lowermost reinforcing ring body, A step of press-fitting into the bottom of the ground through a press-fitting reaction force means, a press-in jack, and a guide member; (4) a step of excavating the bottom of the bottom of the ground closed by the lowermost reinforcing ring; and (5) a press-fitting girder and press-fitting Removing the jack, assembling the next reinforcing ring body, connecting the second-stage reinforcing ring body to the top of the lowermost reinforcing ring body, and (6) a press-fitting girder on the second-stage reinforcing ring body Install the press-fit jack, the lowermost reinforcing ring body and the second-stage reinforcing ring. A step of press-fitting the body into the foundation, and (7) repeating the above-described steps, and a step of press-fitting the reinforcing ring body from the top of the bottom of the bottom to the desired depth in the bottom of the bottom, and (8) from the top of the reinforcing ring. A step of installing a ring-shaped liner plate or steel ring as a cut-off member extending to the surface of the water; and (9) from the top of the bottom floor in a space surrounded by the reinforcing ring body and the ring-shaped liner plate or steel ring. Excavating to a desired depth, attaching a water-stopping material, placing water-stopping concrete, drawing water in the temporary shut-off structure and forming a dry work space, and having an existing structure in water A temporary cut-off method of an object is disclosed (see claim 7 of patent document 2, paragraph 0016 of the specification, FIG. 3 of the drawing, etc.).
しかし、特許文献2に記載の水中の既設構造物の仮締切り工法では、浚渫範囲は限定されているものの、橋脚の断面形状が変化する場合、対応することができないという問題があった。また、鋼製リング体5を水中地盤に圧入する際に正確に圧入することができないという問題もった。   However, the temporary closing method for an existing structure in water described in Patent Document 2 has a problem in that it cannot cope with a change in the cross-sectional shape of the pier, although the range of the trough is limited. In addition, there is a problem that the steel ring body 5 cannot be accurately press-fitted when it is press-fitted into the underwater ground.
特開2003−232044号公報JP 2003-232044 A 特開2005−264500号公報JP 2005-264500 A
そこで、本発明は、上述した問題に鑑みて案出されたものであり、その目的とするところは、浚渫範囲を最小限にするとともに、環境にも悪影響を及ぼすことなく、作業工数及び作業期間を削減して施工費の低減を図ることができ、橋脚の断面形状が変化する場合も対応することができるとともに、水中地盤に正確に圧入することができる既設水中構造物の仮締切り工法を提供することにある。   Therefore, the present invention has been devised in view of the above-described problems, and the object of the present invention is to minimize the range of dredging and reduce the man-hours and work period without adversely affecting the environment. The provisional construction method for existing underwater structures that can be accurately pressed into the underwater ground as well as responding to changes in the cross-sectional shape of the pier can be provided. There is to do.
第1発明に係る既設水中構造物の仮締切り工法は、橋脚などの既設水中構造物の周りを締切り仮設体で締め切ってその内部を排水して本工事を行う既設水中構造物の仮締切り工法であって、前記締切り仮設体を水中地盤に圧入する際に前記既設水中構造物から反力を得るための反力ブラケットを前記既設水中構造物の上部に設置する反力ブラケット設置工程と、前記反力ブラケットで前記既設水中構造物から反力を得つつ、圧入ジャッキにより前記締切り仮設体を水中地盤に圧入するとともに、前記締切り仮設体の内側の水中地盤を掘削する前記締切り仮設体圧入・掘削工程と、を有し、前記締切り仮設体に当接する先端にローラ部材又は摺接部材を有するガイドブラケットにより、前記締切り仮設体をガイドしながら下降させることを特徴とする。   The temporary closing method for an existing underwater structure according to the first invention is a temporary closing method for an existing underwater structure in which the periphery of the existing underwater structure such as a pier is closed with a temporary closing body and the interior is drained to perform the main construction. A reaction force bracket installation step for installing a reaction force bracket for obtaining a reaction force from the existing underwater structure when the deadline temporary structure is press-fitted into the underwater ground; The cut-off temporary body press-fitting and excavating step of digging the underwater ground inside the cut-off temporary body while press-fitting the cut-off temporary body into the underwater ground with a press-fit jack while obtaining a reaction force from the existing underwater structure with a force bracket And a guide bracket having a roller member or a slidable contact member at a tip that contacts the temporary cut-off temporary body, and lowering the temporary cut-off temporary body while guiding it. To.
発明に係る既設水中構造物の仮締切り工法は、第1発明において、前記締切り仮設体の初期の組み立て用の仮受台として仮受ブラケットを設置する仮受ブラケット設置工程と、前記仮受ブラケット上で締切り仮設体の最下段から1段又は複数段組み立てる締切り仮設体の初期組立工程と、前記仮受ブラケットの先端を、ローラ部材又は摺接部材に付け替えて仮受ブラケットを前記ガイドブラケットに変更するブラケット先端付け替え工程と、前記ガイドブラケットで前記締切り仮設体をガイドしながら沈降させる締切り仮設体の沈降工程と、を有していることを特徴とする。 The temporary closing method for an existing underwater structure according to the second aspect of the present invention is the temporary cutting bracket installation step of installing a temporary receiving bracket as a temporary receiving base for initial assembly of the cutoff temporary structure in the first aspect of the invention. An initial assembly process of a temporary cut-off body for assembling one or more stages from the lowest stage of the cut-off temporary structure on the bracket, and the tip of the temporary receiving bracket is replaced with a roller member or a sliding contact member, and the temporary receiving bracket is used as the guide bracket. A bracket tip replacement step to be changed; and a settling step for the cutoff temporary body that sinks while guiding the cutoff temporary body with the guide bracket.
発明に係る既設水中構造物の仮締切り工法は、第1発明又は第2発明において、前記締切り仮設体の下部に、前記締切り仮設体に当接する先端にローラ部材又は摺接部材を有する下部ガイドブラケットを取り付ける下部ガイドブラケット取付工程を有し、前記締切り仮設体を圧入ジャッキにより水中地盤に圧入する際に、前記下部ガイドブラケットでガイドすることを特徴とする。 A temporary closing method for an existing underwater structure according to a third invention is the lower part of the first invention or the second invention , having a roller member or a sliding contact member at a lower end of the cutoff temporary body at a tip abutting the temporary cutoff body. A lower guide bracket attaching step for attaching a guide bracket is provided, and when the cut-off temporary structure is press-fitted into the underwater ground by a press-fitting jack, the lower guide bracket guides.
第4発明に係る既設水中構造物の仮締切り工法は、第3発明において、前記下部ガイドブラケットで前記締切り仮設体が動かないよう保持しつつ、前記締切り仮設体の下端に止水コンクリートを打設する止水処理工程を有することを特徴とする。   A temporary closing method for an existing underwater structure according to a fourth invention is the method according to the third invention, wherein water-stopping concrete is placed at a lower end of the cutoff temporary structure while the lower guide bracket holds the temporary cutoff body so as not to move. It has the water-stop processing process to perform.
第5発明に係る既設水中構造物の仮締切り工法は、第1発明乃至第4発明の何れかの発明において、前記既設水中構造物のフーチングから反力を得て締切り仮設体を引抜くための引抜用鋼材を設置する引抜用鋼材設置工程と、前記引抜用鋼材を用いて前記締切り仮設体を引き抜く締切り仮設体の引き抜き工程と、を有することを特徴とする。 Provisional deadline method of existing underwater structure according to the fifth invention, in any one of the first invention to fourth invention, since the pull out the deadline temporary body to obtain a reaction force from the footing of the existing underwater structures A drawing steel material installation step of installing the drawing steel material, and a drawing step of the cut-off temporary body for drawing out the cut-off temporary structure using the drawing steel material.
第1発明〜第5発明によれば、本工事の作業スペースとなる締切り仮設体の内部だけを浚渫すれば良いので、浚渫範囲を最小限にするとともに、環境にも悪影響を及ぼすことが少なくなる。また、ガイドブラケットにより、締切り仮設体をガイドしながら下降させるので、特許文献1に記載の発明のように、大掛かりな足場を組む必要がないうえ、締切り仮設体の着水の際に、水流により締切り仮設体が傾倒するおそれが少なく、極めて安全である。その上、第1発明〜第5発明によれば、ガイドブラケットでガイドするので橋脚の断面形状が変化する場合も対応することができるとともに、水中地盤に正確に圧入することができる。   According to the first to fifth inventions, it is only necessary to scoop the inside of the temporary cut-off temporary body that is the work space for the construction work, so that the scissor range is minimized and the environment is less adversely affected. . Further, since the cutoff temporary structure is lowered while being guided by the guide bracket, it is not necessary to assemble a large scaffold as in the invention described in Patent Document 1, and the water flow is applied when the cutoff temporary structure is landed. The deadline temporary body is less likely to tilt and is extremely safe. Moreover, according to the first to fifth inventions, since the guide is guided by the guide bracket, it is possible to cope with the case where the cross-sectional shape of the pier changes, and it is possible to accurately press-fit into the underwater ground.
特に、第発明によれば、仮受ブラケットを利用して締切り仮設体の初期の組立を行うことができる。このため、空頭制限を受ける狭隘な場所であっても、また、風等により吊り荷が回転してしまうような場合であっても、締切り仮設体の組立が容易である。その上、仮受ブラケットの先端を付け替えてガイドブラケットに変更し、締切り仮設体の着水時の位置を正確に案内できるので、さらに作業期間を削減して施工費の低減を図ることができる。 In particular, according to the second invention, the initial assembly of the cut-off temporary structure can be performed using the temporary receiving bracket. For this reason, it is easy to assemble the cut-off temporary structure even in a confined place subject to the empty head restriction or even when the suspended load is rotated by wind or the like. In addition, the tip of the temporary support bracket can be changed to a guide bracket to accurately guide the position of the deadline temporary body upon landing, so that the work period can be further reduced and the construction cost can be reduced.
特に、第発明によれば、締切り仮設体を圧入ジャッキにより水中地盤に圧入する際に、下部ガイドブラケットでガイドするので、締切り仮設体の水中地盤への圧入を正確に鉛直下方に案内・誘導することができ、不要な抵抗を受けずにスムーズに圧入することができる。このため、さらに作業期間を削減して施工費の低減を図ることができる。また、下部ガイドブラケットの長さを盛り替えることにより橋脚の断面形状が変化する場合も対応することができる。 In particular, according to the third aspect of the present invention, when the cut-off temporary structure is pressed into the underwater ground by the press-fitting jack, the lower guide bracket guides the press-fitting of the cut-off temporary structure into the underwater ground accurately and guides vertically downward. And can be press-fitted smoothly without receiving unnecessary resistance. For this reason, the work period can be further reduced to reduce the construction cost. Moreover, the case where the cross-sectional shape of a pier changes by changing the length of a lower guide bracket can also be coped with.
特に、第4発明によれば、前記下部ガイドブラケットで前記締切り仮設体が動かないよう保持しつつ、前記締切り仮設体の下端に止水コンクリートを打設するので、止水コンクリートの打設時及び養生時に水流により締切り仮設体が動かないように仮固定することができ、止水コンクリートが上手く固まらないことを防ぐことができる。   In particular, according to the fourth aspect of the present invention, the waterproof concrete is placed at the lower end of the cutoff temporary body while the lower guide bracket holds the cutoff temporary body so that it does not move. It is possible to temporarily fix the cut-off temporary structure so that it does not move due to the water flow during curing, and to prevent the water-stopping concrete from solidifying well.
特に、第5発明によれば、引抜用鋼材を用いて締切り仮設体を引き抜くことができる。このため、締切り仮設体の解体・撤去作業を短時間で容易に行うことができる。このため、さらに作業期間を削減して施工費の低減を図ることができる。   In particular, according to the fifth aspect of the invention, the temporary cut-off body can be pulled out using the steel for drawing. For this reason, the dismantling / removal work of the temporary cut-off temporary body can be easily performed in a short time. For this reason, the work period can be further reduced to reduce the construction cost.
本発明の実施の形態に係る既設水中構造物及び締切り仮設体を示す斜視図である。It is a perspective view which shows the existing underwater structure and deadline temporary structure which concern on embodiment of this invention. 同上の既設水中構造物及び締切り仮設体を示す橋梁の幅方向に沿った鉛直断面図である。It is a vertical sectional view along the width direction of the bridge showing the existing underwater structure and the deadline temporary structure. 同上の既設水中構造物及び締切り仮設体を示す平面図である。It is a top view which shows the existing underwater structure and deadline temporary structure same as the above. 同上の既設水中構造物及び締切り仮設体を示す橋梁の軸方向に沿った鉛直断面図である。It is a vertical sectional view along the axial direction of a bridge showing the existing underwater structure and the deadline temporary structure. 本発明の実施の形態に係る既設水中構造物の仮締切り工法の(1)組立式フロート設置工程を示す橋脚を橋梁の幅方向に見た説明図である。It is explanatory drawing which looked at the bridge pier which shows the (1) assembly type float installation process of the temporary closing method of the existing underwater structure which concerns on embodiment of this invention in the width direction of the bridge. 同上の既設水中構造物の仮締切り工法の(2)天井クレーン設置工程を示す説明図である。It is explanatory drawing which shows the (2) overhead crane installation process of the temporary closing method of the existing underwater structure same as the above. 同上の既設水中構造物の仮締切り工法の(3)反力ブラケット設置工程を示す説明図である。It is explanatory drawing which shows the (3) reaction force bracket installation process of the temporary closing method of the existing underwater structure same as the above. 同上の既設水中構造物の仮締切り工法の(4)仮受ブラケット設置工程を示す説明図である。It is explanatory drawing which shows the (4) temporary receiving bracket installation process of the temporary closing method of the existing underwater structure same as the above. 同上の工程で設置する仮受ブラケットを主に示す側面図である。It is a side view which mainly shows the provisional receiving bracket installed in the process same as the above. 同上の既設水中構造物の仮締切り工法の(5)締切り仮設体の初期組立工程を示す説明図である。It is explanatory drawing which shows the initial stage assembly process of the (5) deadline temporary structure of the temporary deadline construction method of the existing underwater structure same as the above. 同上の既設水中構造物の仮締切り工法の(6)ブラケットの先端付け替え工程で組み立てるガイドブラケットを主に示す側面図である。It is a side view which mainly shows the guide bracket assembled in the tip replacement process of the temporary closing method of the existing underwater structure same as the above (6) bracket tip replacement process. 同上の既設水中構造物の仮締切り工法の(7)締切り仮設体の沈降及び組立工程を示す説明図である。It is explanatory drawing which shows the sedimentation and assembly process of the (7) deadline temporary structure of the temporary deadline construction method of the existing underwater structure same as the above. 同上の既設水中構造物の仮締切り工法の(8)下部ガイドブラケット取付工程を示す説明図である。It is explanatory drawing which shows the (8) lower guide bracket attachment process of the temporary closing method of the existing underwater structure same as the above. 同上の既設水中構造物の仮締切り工法の(9)組立・圧入・掘削工程を示す説明図である。It is explanatory drawing which shows the (9) assembly, press-fit, and excavation process of the temporary closing method of the existing underwater structure same as the above. 同上の(9)圧入・掘削工程が完了した状態を示す説明図である。It is explanatory drawing which shows the state which the (9) press-fit and excavation process same as the above completed. 同上の既設水中構造物の仮締切り工法の(10)止水処理工程を示す説明図である。It is explanatory drawing which shows the (10) water stop process of the temporary closing method of the existing underwater structure same as the above. 同上の既設水中構造物の仮締切り工法の(11)排水工程を示す説明図である。It is explanatory drawing which shows the (11) drainage process of the temporary closing method of the existing underwater structure same as the above. 同上の既設水中構造物の仮締切り工法の(12)注水及び引抜用鋼材の設置工程を示す説明図である。It is explanatory drawing which shows the installation process of the steel material for (12) water injection and drawing of the temporary closing method of the existing underwater structure same as the above. 同上の既設水中構造物の仮締切り工法の(13)締切り仮設体の引き抜き及び解体工程を示す説明図である。It is explanatory drawing which shows the drawing-out and dismantling process of the (13) deadline temporary structure of the temporary deadline construction method of the existing underwater structure same as the above. 同上の既設水中構造物の仮締切り工法の(14)埋め戻し工程を示す説明図である。It is explanatory drawing which shows the (14) backfilling process of the temporary cutoff method of the existing underwater structure same as the above. 同上の既設水中構造物の仮締切り工法の(15)その他仮設の撤去工程を示す説明図である。It is explanatory drawing which shows the removal process of (15) other temporary installations of the temporary closing method of the existing underwater structure same as the above.
以下、本発明に係る既設水中構造物の仮締切り工法を実施するための一実施形態について、図面を参照しながら詳細に説明する。なお、既設水中構造物として河川を横断する道路橋の橋脚を例示して説明する。   Hereinafter, an embodiment for carrying out a temporary closing method for an existing underwater structure according to the present invention will be described in detail with reference to the drawings. In addition, the pier of the road bridge crossing a river is illustrated and demonstrated as an existing underwater structure.
[締切り仮設体の概要]
先ず、図1〜図4を用いて、既設水中構造物の仮締切り工法により仮設する締切り仮設体の全体概要について説明する。図1、図3等に示すように、既設水中構造物の仮締切り工法により仮設する締切り仮設体1は、鋼材からなる平面視で円弧状の複数の締切り部材2が、互いに周方向に沿って組み合わされた円筒状の構造物であり、橋脚Pの水平断面が小判形状をした柱部P1の周りに対して間隔をあけて設置され、内側の水を汲みだして、橋脚Pの調査、補修、補強等の本工事のために橋脚Pとの間にドライな作業エリアを構築することを目的としている。
[Outline of the temporary cut-off body]
First, with reference to FIGS. 1 to 4, an overall outline of a cut-off temporary body temporarily installed by a temporary cut-off method for an existing underwater structure will be described. As shown in FIGS. 1 and 3, etc., a temporary cut-off body 1 that is temporarily installed by a temporary cut-off method for an existing underwater structure has a plurality of arc-shaped cut-off members 2 in a plan view made of a steel material along the circumferential direction. It is a combined cylindrical structure, and the horizontal cross section of the pier P is installed with a space around the oval-shaped column part P1, and the water inside the pier P is pumped to investigate and repair the pier P. The purpose is to construct a dry work area with the pier P for the main work such as reinforcement.
なお、既設水中構造物である橋脚Pは、水平断面が小判形状の柱部P1と、柱部P1上方の左右に張り出した梁部P2と、から主に構成され正面視でT字状の橋脚であり、柱部P1が、平面視で円形のフーチングFと図示しない基礎杭を介して地盤に定着されている。なお、図中のX方向が橋梁の橋軸方向、Y方向が橋梁の幅方向、Z方向が上下方向を示している。   The pier P, which is an existing underwater structure, is mainly composed of a column part P1 having an oval horizontal cross section and a beam part P2 projecting left and right above the column part P1, and is a T-shaped pier in front view. The pillar portion P1 is fixed to the ground via a circular footing F and a foundation pile (not shown) in plan view. In the figure, the X direction indicates the bridge axis direction of the bridge, the Y direction indicates the width direction of the bridge, and the Z direction indicates the vertical direction.
締切り仮設体1は、後で詳述するが、図2、図4等で示すように、橋脚Pの柱部P1に取り付けられた反力ブラケット3で柱部P1から反力を得つつ、油圧ジャッキからなる圧入ジャッキ4により下端が橋脚PのフーチングFの天端に到達するまで各段のロット毎に圧入され、下端内部に止水コンクリート5を打設することにより構築される。なお、図示するように、締切り部材2の左右、上下方向の互いの連結は、ボルト等で連結されている他、補強鋼材で補強されている。   The cut-off temporary body 1 will be described in detail later, and as shown in FIGS. 2 and 4 and the like, the reaction force bracket 3 attached to the column portion P1 of the pier P obtains a reaction force from the column portion P1, while The press-in jack 4 made of a jack is pressed into each lot until the lower end reaches the top end of the footing F of the pier P, and is constructed by placing water-stopping concrete 5 inside the lower end. In addition, as shown in the figure, the left and right and the vertical direction of the cutoff member 2 are reinforced with a reinforcing steel material in addition to being connected with bolts or the like.
また、締切り仮設体1として、円筒状のものを例示したが、勿論、小判形状をした柱部P1に合わせて小判形状としても良いし、柱部が水平断面矩形の場合は、それに応じて平面視矩形の枠体としても良い。要するに、締切り仮設体の形状は、既設水中構造物の形状や本工事に応じた適切な作業スペースを確保することのできる形状であれば良い。   Moreover, although the cylindrical thing was illustrated as the cut-off temporary structure 1, of course, it is good also as an oval shape according to the pillar part P1 made into an oval shape, and when a pillar part is a horizontal cross-section rectangle, it is plane according to it. A rectangular frame may be used. In short, the shape of the temporary cut-off body may be a shape that can secure an appropriate work space according to the shape of the existing underwater structure or the main work.
そして、締切り仮設体を構成する締切り部材として、鋼材からなる締切り部材2を例示したが、勿論、PC(プレキャストコンクリート)材や、他の金属材からなるものであっても構わない。要するに、締切り部材及び締切り仮設体は、水圧や土圧に耐えて一定の作業空間を形成できる程度の剛性と、水密性を有していれば、材質等は鋼材に限定されない。但し、汎用性、繰り返し使用による経済性等を考慮すると、鋼材からなるものが好ましいと云える。   The cut-off member 2 made of steel is exemplified as the cut-off member constituting the cut-off temporary body, but of course, it may be made of PC (precast concrete) material or other metal material. In short, the material and the like are not limited to steel as long as the cutoff member and the temporary cutoff body have rigidity and water tightness that can withstand water pressure and earth pressure to form a fixed working space. However, in view of versatility, economy of repeated use, etc., it can be said that a steel material is preferable.
[既設水中構造物の仮締切り工法]
次に、図5〜図21を用いて、本発明の実施の形態に係る既設水中構造物の仮締切り工法について説明する。なお、既設水中構造物等は、前述の締切り仮設体で説明したのと同様であり、同一の構成は同一符号を付し、説明を省略する。
[Temporary cut-off method for existing underwater structures]
Next, the temporary closing method for the existing underwater structure according to the embodiment of the present invention will be described with reference to FIGS. In addition, the existing underwater structure etc. are the same as that of having demonstrated with the above-mentioned temporary cut-off temporary body, The same code | symbol is attached | subjected and description is abbreviate | omitted.
(1)組立式フロート設置工程
先ず、図5に示すように、作業用の足場として橋脚Pの周りに組立式フロート6を設置する。この組立式フロート6は、平面視矩形の複数のフロートが橋脚Pを中心に組み合わされて平面視で矩形の枠状となったものであり、部材の揚重その他作業上の足場として機能する。
(1) Assembly-type float installation process First, as shown in FIG. 5, the assembly-type float 6 is installed around the pier P as a scaffold for work. The assembly type float 6 is a rectangular frame shape in plan view in which a plurality of floats having a rectangular shape in plan view are combined with the pier P as a center, and functions as a scaffold for lifting members and the like.
(2)天井クレーン設置工程
次に、図6に示すように、空頭制限のある橋梁の桁下に資材を揚重、運搬するための天井クレーン7を必要数設置する。この天井クレーン7は、電動ホイストなどであり、組立式フロート6から上昇又は下降の操作が可能であればウィンチなど電動以外の動力であっても構わない。また、天井クレーン7は、クランプ等で盛替え容易に取り付けても良いし、ランウェイ上を水平移動可能に構成しても良い。
(2) Overhead Crane Installation Step Next, as shown in FIG. 6, the necessary number of overhead cranes 7 for installing and transporting materials are installed under the bridge girder with a sky head restriction. The overhead crane 7 is an electric hoist or the like, and may be a non-electric power such as a winch as long as the ascending or descending operation can be performed from the assembly type float 6. In addition, the overhead crane 7 may be attached easily with a clamp or the like, or may be configured to be horizontally movable on the runway.
(3)反力ブラケット設置工程
次に、図7に示すように、締切り仮設体1を圧入する際に橋脚Pから反力を得るための反力ブラケット3を橋脚Pの柱部P1の上部に取り付ける。この反力ブラケット3は、鋼製のブラケットであり、柱部P1に穿孔された孔を利用してケミカルアンカーなどの後施工アンカーで柱部P1に固定される。また、反力ブラケット3は、柱部P1の上部に、揚重スペースが十分に取れるよう空頭制限となる梁部P2の直下となる高さに設けることが好ましい。設置数は、必要数で良いが、本実施の形態では、橋軸方向に見た橋脚Pの正面、背面側に2つずつ、両側面側である梁部P2直下に1つずつの計6基設置している(図3参照)。なお、反力ブラケット3として方杖が下方に位置するものを例示したが、図示したものと上下が逆であっても良いことは云うまでもない。
(3) Reaction Force Bracket Installation Step Next, as shown in FIG. 7, the reaction force bracket 3 for obtaining a reaction force from the pier P when press-fitting the temporary cut-off temporary body 1 is provided on the upper portion of the column portion P1 of the pier P. Install. The reaction force bracket 3 is a steel bracket, and is fixed to the pillar portion P1 by a post-installed anchor such as a chemical anchor using a hole drilled in the pillar portion P1. Moreover, it is preferable that the reaction force bracket 3 is provided at a height directly below the beam portion P2 that is limited to the empty head so that a sufficient lifting space can be obtained at the upper portion of the column portion P1. The number of installations may be the required number, but in the present embodiment, a total of 6 one by two on the front and back sides of the pier P viewed in the direction of the bridge axis, and one on each side directly below the beam part P2. The base is installed (see Fig. 3). Note that the reaction force bracket 3 is illustrated with the wand positioned below, but needless to say, the illustrated one may be upside down.
(4)仮受ブラケット設置工程
次に、図8に示すように、締切り仮設体1の組み立て用の仮受台として橋脚Pの柱部P1側が基端部となるよう仮受ブラケット8を柱部P1に取り付け設置する。この仮受ブラケット8は、図9に示すように、鋼製のブラケットであり、その先端に、仮受台となる仮受部材8aがボルト止めにより連結されている。この仮受部材8aは、ブラケットのビーム材を延長する延長部材8bの上面に仮受台となるH形鋼からなる受けピース8cが溶接されている。なお、橋脚Pの水深が浅いような場合、締切り仮設体の外側に足場を組み、その足場が基端部となるよう仮受ブラケット8を設置することも可能である。
(4) Temporary Bracket Installation Step Next, as shown in FIG. 8, the temporary bracket 8 is used as a temporary support for assembling the cutoff temporary structure 1 so that the column P1 side of the pier P becomes the base end. Install and install on P1. As shown in FIG. 9, the temporary bracket 8 is a steel bracket, and a temporary receiving member 8 a serving as a temporary holder is connected to the tip of the bracket by bolting. In this temporary receiving member 8a, a receiving piece 8c made of H-shaped steel serving as a temporary receiving base is welded to the upper surface of an extending member 8b extending the beam material of the bracket. In addition, when the water depth of the bridge pier P is shallow, it is also possible to assemble a scaffolding on the outer side of the temporary cut-off temporary body and install the temporary support bracket 8 so that the scaffolding becomes a base end part.
仮受ブラケット8の設置高さは、この仮受ブラケット8上で組み立てる締切り仮設体1の段数と、反力ブラケット3との離間距離、圧入ジャッキ4の大きさ等を勘案して定められるものである。本実施の形態に係る仮受ブラケット8の設置高さは、図8に示すように、施工時水位以下となるため、仮受ブラケット8は、ダイバーDにより水面下に複数の後施工アンカーA(図9参照)にボルト止めされることにより柱部P1に取り付けられている。   The installation height of the temporary bracket 8 is determined in consideration of the number of steps of the cutoff temporary body 1 assembled on the temporary bracket 8, the separation distance from the reaction force bracket 3, the size of the press-fit jack 4, and the like. is there. As shown in FIG. 8, the installation height of the temporary bracket 8 according to the present embodiment is equal to or lower than the water level at the time of construction. Therefore, the temporary bracket 8 is provided with a plurality of post-construction anchors A ( It is attached to the pillar portion P1 by being bolted to (see FIG. 9).
(5)締切り仮設体の初期組立工程
次に、図10に示すように、前工程で設置した仮受ブラケット8上において、刃口部となる最下段の締切り部材2’及び2段目(2ロット目)の締切り部材2を組み立て、2段からなる締切り仮設体1を構築する。勿論、ここで締切り仮設体を組み立てる段数(ロット数)は、空頭制限や反力ブラケット3の設置できる高さ、施工時の水位等に応じて適宜定めれば良い。
(5) Initial Assembly Process of Cut-off Temporary Body Next, as shown in FIG. 10, on the temporary receiving bracket 8 installed in the previous process, the lowermost cut-off member 2 ′ and the second stage (2 Assembling the lot member 2), the temporary cut-off body 1 having two stages is constructed. Of course, the number of steps (number of lots) for assembling the temporary cut-off body here may be determined appropriately according to the empty head limit, the height at which the reaction force bracket 3 can be installed, the water level at the time of construction, and the like.
このように、波や風などで上下左右に揺れる組立式フロート6上ではなく、既設構造物である橋脚Pの柱部P1に支持される仮受ブラケット8上において締切り仮設体1を組み立てるので、ボルト締めや部材の揚重・荷降ろしなどの作業効率が格段に向上し、工期を短縮して施工費を削減することができる上、安全性も格段に向上する。   Thus, the cut-off temporary structure 1 is assembled on the temporary bracket 8 supported by the pillar portion P1 of the pier P, which is an existing structure, not on the assembly type float 6 that swings up and down and left and right due to waves and winds. Work efficiency such as bolting, lifting and unloading of parts can be greatly improved, construction period can be shortened and construction costs can be reduced, and safety can be improved significantly.
(6)ブラケットの先端付け替え工程
次に、2段目まで組み立てた締切り仮設体1を天井クレーン7で一旦吊り上げた後、緊結していたボルトを外して図9で示した仮受ブラケット8の先端の仮受部材8aを、図11に示すローラ部材8a’に付け替え、仮受ブラケット8からガイドブラケット8’に変更する。このガイドブラケット8’は、図11に示すように、複数のローラ機構を有するローラ部材8a’により、当接する締切り仮設体1の内壁を損傷することなくスライドするように締切り仮設体1をガイドする機能を有している。
(6) Bracket Tip Replacement Process Next, the temporary cut-off temporary body 1 assembled up to the second stage is once lifted by the overhead crane 7, and then the bolts that have been tightened are removed and the tip of the temporary bracket 8 shown in FIG. The temporary receiving member 8a is replaced with a roller member 8a 'shown in FIG. 11, and the temporary receiving bracket 8 is changed to the guide bracket 8'. As shown in FIG. 11, the guide bracket 8 ′ guides the temporary cut-off temporary body 1 by a roller member 8 a ′ having a plurality of roller mechanisms so as to slide without damaging the inner wall of the cut-off temporary temporary body 1. It has a function.
なお、このガイドブラケット8’は、ローラ部材8a’のようにローラ接合する部材の代わりに、ステンレス鋼板や耐摩耗性樹脂(耐摩耗性を向上させた6ナイロン:(登録商標)MCナイロン等)などからなる曲面構造で摩擦抵抗を低減する機構で締切り仮設体1の内壁と摺接する摺接部材としても同等の機能を発揮することができる。   The guide bracket 8 'is made of a stainless steel plate or wear-resistant resin (6 nylon with improved wear resistance: (registered trademark) MC nylon, etc.) instead of a roller-joined member such as the roller member 8a'. An equivalent function can also be exhibited as a sliding contact member that is in sliding contact with the inner wall of the temporary cut-off temporary body 1 by a mechanism that reduces the frictional resistance with a curved surface structure composed of the like.
(7)締切り仮設体の沈降及び組立工程
次に、図12に示すように、2段目まで組み立てた締切り仮設体1を、ガイドブラケット8’のローラ部材8a’に締切り仮設体1の内壁を滑らせてガイドしながら、3段目が組み立て可能な高さまで天井クレーン7により吊り降ろして水中に着水・沈降(下降)させる。そして、上方にできたスペースを利用して、締切り仮設体1の3段目(3ロット目)を組み立てる。
(7) Settling and assembly process of deadline temporary body Next, as shown in FIG. 12, the deadline temporary body 1 assembled up to the second stage is attached to the roller member 8a 'of the guide bracket 8' and the inner wall of the deadline temporary body 1 is attached. While sliding and guiding, it is suspended by the overhead crane 7 to a height at which the third stage can be assembled, and is landed and settled (down) in the water. Then, the third stage (third lot) of the temporary cut-off temporary body 1 is assembled using the space formed above.
このように、締切り仮設体1を水中に着水し沈降(下降)させる際に、ガイドブラケット8’でガイドしながら沈降させることができるので、締切り仮設体1が着水時等に河川などの水流で押し流されることがなく、効率よく短時間で安全に締切り仮設体1を鉛直に下降させることができる。その上、締切り仮設体1の3段目(3ロット目)を組み立てる際にも、ガイドブラケット8’でガイドされているので、揺れが格段に低減され、組立作業の作業効率も向上する。   In this way, when the deadline temporary body 1 is submerged in water and settled (lowered), it can be settled while being guided by the guide bracket 8 ′. Without being pushed away by the water flow, the cutoff temporary body 1 can be vertically lowered efficiently and safely in a short time. In addition, when assembling the third stage (third lot) of the temporary cut-off body 1, since it is guided by the guide bracket 8 ', the shaking is remarkably reduced and the working efficiency of the assembling work is improved.
(8)下部ガイドブラケット取付工程
次に、図13に示すように、締切り仮設体1を沈降させ、締切り仮設体1の4段目を組み立てた上、締切り仮設体1の下部(本実施の形態では、2段目)に、下部ガイドブラケット9を取り付けて、水中地盤に締切り仮設体1の下端を着底させる。なお、施工時水位と水中地盤の天端までの距離が深い場合は、前述の締切り仮設体1の沈降・組み立てを必要回(段)繰り返す。
(8) Lower Guide Bracket Attaching Step Next, as shown in FIG. 13, the temporary cut-off temporary body 1 is settled, the fourth stage of the final cut-off temporary body 1 is assembled, and the lower part of the temporary cut-off temporary body 1 (this embodiment) Then, the lower guide bracket 9 is attached to the second stage), and the lower end of the cutoff temporary body 1 is grounded to the underwater ground. In addition, when the distance from the water level at the time of construction to the top of the underwater ground is deep, the above-described settling and assembling of the temporary cut-off body 1 is repeated as many times as necessary.
この下部ガイドブラケット9は、ブラケットの基端側が締切り仮設体1の内壁となっているだけで、図11で示したガイドブラケット8’と略同一構成となっており、橋脚Pの柱部P1と当接する先端が、ローラ部材8a’と同一構成のローラ部材9aとなっている。この下部ガイドブラケット9は、締切り仮設体1の圧入時の刃先部である下端を柱部P1に沿って鉛直下方にガイドする機能を有している。また、橋脚の柱部にテーパがついているなど橋脚の断面形状が変化する場合は、下部ガイドブラケット9の長さを盛り替えながらガイドさせると好ましい。   The lower guide bracket 9 has substantially the same configuration as the guide bracket 8 ′ shown in FIG. 11 except that the base end side of the bracket is the inner wall of the cutoff temporary structure 1. The abutting tip is a roller member 9a having the same configuration as the roller member 8a ′. The lower guide bracket 9 has a function of guiding a lower end, which is a cutting edge portion at the time of press-fitting the cutoff temporary structure 1, vertically downward along the column portion P <b> 1. In addition, when the cross-sectional shape of the pier changes, for example, the pillar portion of the pier is tapered, it is preferable to guide while changing the length of the lower guide bracket 9.
(9)組立・圧入・掘削工程
次に、図14に示すように、柱部P1に取り付けられた反力ブラケット3で柱部P1から反力を得つつ、圧入ジャッキ4により締切り仮設体1を水中地盤に圧入する。本実施の形態では、間隔の調整と締切り仮設体1が損傷するのを防止するため圧入ジャッキ4と締切り仮設体1上端との間に角材(端太角)や鋼材などの噛まし材を噛まして圧入ジャッキ4で圧入している。
(9) Assembly / Press-fit / Drilling Step Next, as shown in FIG. 14, the cut-off temporary structure 1 is moved by the press-fit jack 4 while the reaction force bracket 3 attached to the column P1 obtains a reaction force from the column P1. Press fit into the underwater ground. In this embodiment, in order to adjust the interval and prevent the temporary cut-off temporary body 1 from being damaged, a biting material such as a square member (end thick corner) or a steel material is engaged between the press-fit jack 4 and the upper end of the cut-off temporary set 1. Moreover, it is press-fitted with a press-fitting jack 4.
また、締切り仮設体1の圧入作業と併行してダイバーDによりバキュームポンプ等を用いて締切り仮設体1内側の地盤を掘削又は浚渫(排土)する。   In parallel with the press-fitting operation of the temporary cut-off body 1, the ground inside the cut-off temporary body 1 is excavated or dredged (soiled) by a diver D using a vacuum pump or the like.
そして、圧入により空いた上方のスペースを利用して締切り仮設体1の次の段(図示場合は、5段目)を組み立てる。このように、締切り仮設体1の下端が、橋脚PのフーチングFの天端まで到達するまで、組立・圧入・掘削工程を必要段(ロット)繰り返す。フーチングFの天端まで到達した状態が、図15である。   Then, the next stage (the fifth stage in the figure) of the cutoff temporary body 1 is assembled using the upper space vacated by the press-fitting. In this way, the assembly, press-fitting and excavation steps are repeated until the lower end of the cutoff temporary body 1 reaches the top end of the footing F of the pier P. FIG. 15 shows a state where the top end of the footing F has been reached.
(10)止水処理工程
次に、図16に示すように、ダイバーDにより水中型枠を設置し、締切り仮設体1の下端と、水中型枠との間の隙間に止水コンクリート5を打設する。このとき、止水コンクリート5の直上に、下部ガイドブラケット9が存在するため、止水コンクリート5の打設時及び養生時に水流により締切り仮設体1が動かないように仮固定することができ、止水コンクリート5が上手く固まらないことを防ぐことができる。即ち、下部ガイドブラケット9は、止水コンクリート5が硬化するまで間型枠を保持する支保工としての機能も有している。
(10) Water stop treatment step Next, as shown in FIG. 16, the underwater mold is installed by the diver D, and the water stop concrete 5 is driven into the gap between the lower end of the cutoff temporary body 1 and the underwater mold. Set up. At this time, since the lower guide bracket 9 exists immediately above the water-stopping concrete 5, it can be temporarily fixed so that the cut-off temporary body 1 does not move due to a water flow when the water-stopping concrete 5 is placed and cured. It is possible to prevent the water concrete 5 from being hardened well. That is, the lower guide bracket 9 also has a function as a support work for holding the mold frame until the water-stopping concrete 5 is hardened.
(11)排水工程
次に、図17に示すように、止水コンクリート5が硬化した後、天井クレーン7等を用いて下部ガイドブラケット9、反力ブラケット3、及び圧入ジャッキ4等を撤去する。そして、ポンプ等を用いて締切り仮設体1内の排水を行い、橋脚Pとの間にドライな作業エリアを構築する。
(11) Drainage process Next, as shown in FIG. 17, after the waterproofing concrete 5 is hardened, the lower guide bracket 9, the reaction force bracket 3, the press-fit jack 4, and the like are removed using the overhead crane 7 or the like. And the drainage in the deadline temporary body 1 is drained using a pump etc., and a dry work area is constructed between the bridge piers P.
その後、耐震補強のために橋脚Pの周りに補強部材P3(例えば、補強鋼板)(図18参照)を巻き付けるなど橋脚Pの調査、補修、補強等の本工事を行う。このとき、本工事の進捗状況に応じてガイドブラケット8’も撤去する。   After that, the main work such as investigation, repair, reinforcement and the like of the bridge pier P is performed such as wrapping a reinforcing member P3 (for example, a reinforcing steel plate) (see FIG. 18) around the pier P for earthquake resistance reinforcement. At this time, the guide bracket 8 'is also removed according to the progress of the main work.
(12)注水及び引抜用鋼材設置工程
次に、図18に示すように、フーチングFから反力を得て締切り仮設体1を引く抜くための引抜用鋼材10を、締切り仮設体1の内壁に沿って橋脚PのフーチングF上に立設する。また、引抜用鋼材10の最上段に油圧ジャッキからなる引抜ジャッキ11を設置するとともに、締切り仮設体1の上端に、引抜ピース2aを取り付ける。
(12) Water Injection and Pulling Steel Material Installation Step Next, as shown in FIG. 18, a drawing steel material 10 for pulling out the cut-off temporary body 1 by obtaining a reaction force from the footing F is applied to the inner wall of the cut-off temporary body 1. Along the footing F of the pier P along. In addition, a drawing jack 11 made of a hydraulic jack is installed on the uppermost stage of the drawing steel material 10, and a drawing piece 2 a is attached to the upper end of the cutoff temporary structure 1.
続いて、ポンプ等を用いて、周囲の水を締切り仮設体1内に注水する。注水と併せて、ダイバーDにより締切り仮設体1を連結している最下段のボルトを切断し、1段目の締切り部材2’だけ切り離す。   Subsequently, the surrounding water is poured into the cutoff temporary body 1 using a pump or the like. Together with the water injection, the lowermost bolt connecting the cut-off temporary structure 1 is cut by the diver D, and only the first cut-off member 2 'is cut off.
(13)締切り仮設体の引き抜き及び解体工程
次に、図19に示すように、引抜ジャッキ11を用いて、最下段の締切り部材2’だけ残して締切り仮設体1を引き抜き、上段から順次解体して行く。また、引抜ピース2aは、その都度、盛替えて、最上段に取り付ける。
(13) Drawing-off and dismantling process of the cut-off temporary body Next, as shown in FIG. 19, using the pull-out jack 11, the cut-off temporary body 1 is pulled out leaving only the lowermost cut-off member 2 'and disassembled sequentially from the upper stage. Go. Moreover, the drawing piece 2a is refilled each time and attached to the uppermost stage.
(14)埋め戻し工程
次に、図20に示すように、締切り仮設体1を引き抜き解体した後、元の水中地盤に合わせて締切り仮設体1があった場所を埋め戻す。このとき、引き抜き残した最下段の締切り部材2’と止水コンクリート5も一緒に埋め戻す。但し、経済性、工程、土被りなど諸条件を勘案して締切り部材2’と止水コンクリート5も撤去しても構わない。
(14) Backfilling step Next, as shown in FIG. 20, after the cut-off temporary body 1 is pulled out and disassembled, the place where the cut-off temporary body 1 was located is backfilled according to the original underwater ground. At this time, the lowermost cut-off member 2 ′ and the water-stopping concrete 5 that have been pulled out are backfilled together. However, the cut-off member 2 ′ and the water-stopping concrete 5 may be removed in consideration of various conditions such as economy, process, and covering.
(15)その他仮設の撤去工程
最後に、図21に示すように、天井クレーン7や組立フロート6など、その他の仮設物を撤去して、本実施の形態に係る既設水中構造物の仮締切り工法が終了する。
(15) Other Temporary Removal Process Finally, as shown in FIG. 21, other temporary objects such as the overhead crane 7 and the assembly float 6 are removed, and the temporary undercutting method for the existing underwater structure according to the present embodiment. Ends.
以上に説明した本発明の実施の形態に係る既設水中構造物の仮締切り工法によれば、本工事の作業スペースとなる締切り仮設体1の内部だけを浚渫すれば良いので、浚渫範囲を最小限にするとともに、環境にも悪影響を及ぼすことが少なくなる。また、ガイドブラケット8’により、締切り仮設体1をガイドしながら沈降又は圧入(下降)させるので、大掛かりな足場を組む必要がないうえ、締切り仮設体1の着水の際に、水流により締切り仮設体1が傾倒するおそれが少なく、極めて安全で作業期間を削減することができる。   According to the above-described temporary closing method for an existing underwater structure according to the embodiment of the present invention, only the inside of the temporary closing body 1 that becomes the work space of the main work needs to be scooped, so that the scissor range is minimized. And less harmful to the environment. In addition, the guide bracket 8 'guides the cut-off temporary body 1 while settling or press-fitting (lowering), so there is no need to assemble a large scaffold, and when the cut-off temporary body 1 is landed, the cut-off temporary body 1 is temporarily set by water flow. There is little possibility that the body 1 tilts, and it is extremely safe and the work period can be reduced.
また、締切り仮設体1を圧入ジャッキ4により水中地盤に圧入する際に、下部ガイドブラケット9でガイドするので、締切り仮設体1の水中地盤への圧入を正確に鉛直下方に案内・誘導することができ、不要な抵抗を受けずにスムーズに圧入することができる。このため、作業期間を削減して施工費の低減を図ることができる。   Further, when the deadline temporary body 1 is pressed into the underwater ground by the press-fit jack 4, it is guided by the lower guide bracket 9, so that the press-fitting of the deadline temporary body 1 into the underwater ground can be accurately guided and guided vertically downward. It is possible to press-fit smoothly without receiving unnecessary resistance. For this reason, a work period can be reduced and construction cost can be reduced.
そのうえ、本実施の形態に係る既設水中構造物の仮締切り工法によれば、仮受ブラケット8を利用して締切り仮設体1の初期の組立を行うことができる。このため、空頭制限を受ける狭隘な場所であっても、また、風等により吊り荷が回転してしまうような場合であっても、締切り仮設体1の組立が容易である。その上、仮受ブラケット8の先端を付け替えてガイドブラケット9に変更し、締切り仮設体1の着水時の位置を正確に案内できるので、さらに作業期間を削減して施工費の低減を図ることができる。   In addition, according to the temporary closing method of the existing underwater structure according to the present embodiment, the initial assembly of the temporary closing body 1 can be performed using the temporary receiving bracket 8. For this reason, it is easy to assemble the cut-off temporary structure 1 even in a narrow place where the head is limited or even when the suspended load is rotated by wind or the like. In addition, the tip of the temporary support bracket 8 can be changed to a guide bracket 9 to accurately guide the position of the deadline temporary body 1 upon landing, thereby further reducing the work period and reducing the construction cost. Can do.
さらに、引抜用鋼材10を利用して引抜ジャッキ11により締切り仮設体1を引き抜くことができるので、締切り仮設体1の解体・撤去作業を短時間で容易に行うことができる。このため、さらに作業期間を削減して施工費の低減を図ることができる。   Furthermore, since the cut-off temporary body 1 can be pulled out by the pull-out jack 11 using the steel material 10 for drawing, the dismantling / removal work of the cut-off temporary body 1 can be easily performed in a short time. For this reason, the work period can be further reduced to reduce the construction cost.
以上、本発明の実施の形態に係る既設水中構造物の仮締切り工法について詳細に説明したが、前述した又は図示した実施の形態は、何れも本発明を実施するにあたって具体化した一実施の形態を示したものに過ぎず、これらによって本発明の技術的範囲が限定的に解釈されてはならないものである。   As mentioned above, although the temporary closing method of the existing underwater structure which concerns on embodiment of this invention was demonstrated in detail, all the embodiment mentioned above or illustrated was implemented in implementing this invention. However, the technical scope of the present invention should not be construed in a limited manner.
特に、各種ブラケットは、方杖のあるものに限定されず、単なる壁面に突設された条材であっても構わない。また、圧入ジャッキ4や引抜ジャッキ11等も油圧ジャッキに限られず、電動シリンダ等の他の動力機構であっても構わない。このような機構や部材であても、前記作用効果を奏することは明らかである。   In particular, the various brackets are not limited to those having a cane, and may be strips provided on a simple wall surface. The press-fit jack 4 and the pull-out jack 11 are not limited to hydraulic jacks, and may be other power mechanisms such as an electric cylinder. It is clear that even such a mechanism or member has the above-described effects.
P :橋脚
P1 :柱部
P2 :梁部
P3 :補強部材
F :フーチング
1 :締切り仮設体
2 :締切り部材
2a :引抜ピース
3 :反力ブラケット
4 :圧入ジャッキ
5 :止水コンクリート
6 :組立式フロート
7 :天井クレーン
8 :仮受ブラケット
8a :仮受部材
8’ :ガイドブラケット
8a’ :ローラ部材
9 :下部ガイドブラケット
9a :ローラ部材
10 :引抜用鋼材
11 :引抜ジャッキ
P: Pier P1: Column P2: Beam P3: Reinforcement member F: Footing 1: Closing temporary body 2: Closing member 2a: Pull-out piece 3: Reaction force bracket 4: Press-in jack 5: Waterproof concrete 6: Assembling type float 7: Overhead crane 8: Temporary receiving bracket 8a: Temporary receiving member 8 ': Guide bracket 8a': Roller member 9: Lower guide bracket 9a: Roller member 10: Pulling steel 11: Pulling jack

Claims (5)

  1. 橋脚などの既設水中構造物の周りを締切り仮設体で締め切ってその内部を排水して本工事を行う既設水中構造物の仮締切り工法であって、
    前記締切り仮設体を水中地盤に圧入する際に前記既設水中構造物から反力を得るための反力ブラケットを前記既設水中構造物の上部に設置する反力ブラケット設置工程と、
    前記反力ブラケットで前記既設水中構造物から反力を得つつ、圧入ジャッキにより前記締切り仮設体を水中地盤に圧入するとともに、前記締切り仮設体の内側の水中地盤を掘削する前記締切り仮設体圧入・掘削工程と、を有し、
    前記締切り仮設体に当接する先端にローラ部材又は摺接部材を有するガイドブラケットにより、前記締切り仮設体をガイドしながら下降させること
    を特徴とする既設水中構造物の仮締切り工法。
    A temporary closing method for an existing underwater structure such as a bridge pier and the like that is closed by a temporary cut-off body and draining the inside of the underwater structure to perform the main work.
    A reaction force bracket installation step of installing a reaction force bracket on the upper part of the existing underwater structure to obtain a reaction force from the existing underwater structure when the deadline temporary structure is press-fitted into the underwater ground;
    While receiving reaction force from the existing underwater structure with the reaction force bracket, press-fit the deadline temporary body into the underwater ground with a press-fitting jack, and excavate the underwater ground inside the deadline temporary body. A drilling process,
    A temporary cutoff method for an existing underwater structure, wherein the cutoff temporary structure is lowered while being guided by a guide bracket having a roller member or a sliding contact member at a tip abutting against the temporary cutoff body.
  2. 前記締切り仮設体の初期の組み立て用の仮受台として仮受ブラケットを設置する仮受ブラケット設置工程と、
    前記仮受ブラケット上で締切り仮設体の最下段から1段又は複数段組み立てる締切り仮設体の初期組立工程と、
    前記仮受ブラケットの先端を、ローラ部材又は摺接部材に付け替えて仮受ブラケットを前記ガイドブラケットに変更するブラケット先端付け替え工程と、
    前記ガイドブラケットで前記締切り仮設体をガイドしながら沈降させる締切り仮設体の沈降工程と、を有していること
    を特徴とする請求項1に記載の既設水中構造物の仮締切り工法。
    A provisional bracket installation step of installing a provisional bracket as a provisional base for initial assembly of the deadline provisional body;
    An initial assembly step of a cutoff temporary structure for assembling one or more stages from the lowest level of the cutoff temporary structure on the temporary bracket;
    A bracket tip replacement step in which the tip of the provisional bracket is replaced with a roller member or a sliding contact member to change the provisional bracket to the guide bracket;
    The temporary closing method for an existing underwater structure according to claim 1, further comprising: a sinking step of a cutoff temporary body that sinks while guiding the cutoff temporary body with the guide bracket.
  3. 前記締切り仮設体の下部に、前記締切り仮設体に当接する先端にローラ部材又は摺接部材を有する下部ガイドブラケットを取り付ける下部ガイドブラケット取付工程を有し、
    前記締切り仮設体を圧入ジャッキにより水中地盤に圧入する際に、前記下部ガイドブラケットでガイドすること
    を特徴とする請求項1又は2に記載の既設水中構造物の仮締切り工法。
    A lower guide bracket attaching step for attaching a lower guide bracket having a roller member or a sliding contact member at a tip abutting on the deadline temporary body at a lower portion of the deadline temporary body;
    The temporary undercutting method for an existing underwater structure according to claim 1 or 2, wherein the lower cutout temporary structure is guided by the lower guide bracket when being pressed into the underwater ground by a press-fit jack.
  4. 前記下部ガイドブラケットで前記締切り仮設体が動かないよう保持しつつ、前記締切り仮設体の下端に止水コンクリートを打設する止水処理工程を有すること
    を特徴とする請求項3に記載の既設水中構造物の仮締切り工法。
    The existing underwater according to claim 3, further comprising: a water stopping treatment step of placing water stopping concrete on a lower end of the cutoff temporary body while holding the temporary suspension body so as not to move by the lower guide bracket. A temporary cut-off method for structures.
  5. 前記既設水中構造物のフーチングから反力を得て締切り仮設体を引抜くための引抜用鋼材を設置する引抜用鋼材設置工程と、
    前記引抜用鋼材を用いて前記締切り仮設体を引き抜く締切り仮設体の引き抜き工程と、を有すること
    を特徴とする請求項1乃至4の何れかに記載の既設水中構造物の仮締切り工法。
    And withdrawing steel material placing step of placing a pulling steel material for pull out the deadline temporary body to obtain a reaction force from the footing of the existing underwater structures,
    The temporary undercutting method for an existing underwater structure according to any one of claims 1 to 4, further comprising: a pulling-out process of a cut-off temporary body that pulls out the temporary cut-off temporary body using the steel material for drawing.
JP2014137541A 2014-07-03 2014-07-03 Temporary closing method for existing underwater structures Active JP6010070B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2014137541A JP6010070B2 (en) 2014-07-03 2014-07-03 Temporary closing method for existing underwater structures

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2014137541A JP6010070B2 (en) 2014-07-03 2014-07-03 Temporary closing method for existing underwater structures

Publications (2)

Publication Number Publication Date
JP2016014290A JP2016014290A (en) 2016-01-28
JP6010070B2 true JP6010070B2 (en) 2016-10-19

Family

ID=55230686

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2014137541A Active JP6010070B2 (en) 2014-07-03 2014-07-03 Temporary closing method for existing underwater structures

Country Status (1)

Country Link
JP (1) JP6010070B2 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110939147A (en) * 2019-11-12 2020-03-31 中国铁建大桥工程局集团有限公司 Method for accurately positioning inserting and beating steel casing of double-wall steel suspension box cofferdam

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106012875B (en) * 2016-07-28 2017-10-13 上海浦东新区公路建设发展有限公司 The method of the local lossless jacking replacing time of plate girder bridge
JP6351776B1 (en) * 2017-03-08 2018-07-04 第一建設工業株式会社 Installation method of temporary closing structure used for bridge pier repair and reinforcement work
CN106930192B (en) * 2017-04-21 2018-12-18 中交一公局第一工程有限公司 Assembled variable cross-section contracture sliding mode system and its construction method
JP6274688B1 (en) * 2017-05-22 2018-02-07 株式会社高知丸高 Temporary deadline construction method
CN107012796A (en) * 2017-05-25 2017-08-04 山东大学 A kind of wide, bracket of No. zero block construction of squat pier box beam and construction method
CN107740341A (en) * 2017-09-22 2018-02-27 陈彬 A kind of municipal bridge pier base and its method of work
CN108872376A (en) * 2018-04-12 2018-11-23 河海大学 A kind of underwater cylinder bridge pier visits the fixation bracket and its application method of damage detecting instrument device

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH09177083A (en) * 1995-12-26 1997-07-08 Daiho Constr Co Ltd Cofferdam caisson and cofferdam construction method
JP4381855B2 (en) * 2004-03-17 2009-12-09 オリエンタル白石株式会社 Temporary cut-off structure and temporary cut-off method for underwater existing structures
JP4509812B2 (en) * 2005-01-31 2010-07-21 五洋建設株式会社 Dry work box and installation method
JP4977529B2 (en) * 2007-05-30 2012-07-18 Jfe建材株式会社 Still water structure, temporary closing structure

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110939147A (en) * 2019-11-12 2020-03-31 中国铁建大桥工程局集团有限公司 Method for accurately positioning inserting and beating steel casing of double-wall steel suspension box cofferdam

Also Published As

Publication number Publication date
JP2016014290A (en) 2016-01-28

Similar Documents

Publication Publication Date Title
US9567720B2 (en) Offshore platform for a marine environment
KR101014796B1 (en) Top-down underground construction method using prefabricated concrete column member as temporary bridge column
CN102094425B (en) Foundation pit construction method adopting shallow buried depth Larsen steel plate pile as protective cofferdam
JP4793634B2 (en) Temporary deadline construction method
CN105133627B (en) Construction under single wall steel sheet-pile cofferdam flowing water state
CN104196034A (en) Foundation pit construction method employing steel sheet piles as support cofferdam
CN101672041B (en) Top-down construction method of large underground structure outer wall
CN104711994A (en) Foundation pit deep well rainfall and plugging construction method
KR100617949B1 (en) Pile Groups Construction Method of Weak Bedding Bone Using Caission
US8297885B2 (en) Method of erecting a building structure in a water basin
CN101691751B (en) Construction method for making ultra-long artificial excavating pile penetrate cave and ultra-long pile penetrating cave
JP2009084919A (en) Ground excavating method
CN103741657A (en) Construction method of large multifunctional over-water construction platform
CN102720140B (en) Large-span prestress concrete continuous beam deepwater pier construction process
US20100232878A1 (en) Universal Framed Cofferdam
CN106968256B (en) Foundation pit assembled steel trestle construction method
CN103306289A (en) Foundation pit piled anchor dado concrete anchor cable top beam structure and construction method thereof
KR101859367B1 (en) Method for constructing vertical structure in vertical tunnel using top down method
CN106638640B (en) Construction method without bottom concrete combined type cofferdam under the conditions of formation geology
CN108086340B (en) Open caisson construction structure and construction method thereof
CN103195076A (en) Method for constructing silt deep foundation pit tower crane foundation
CN104060617B (en) The prefabricated assembled inner support system of foundation pit support system and construction method
US1943800A (en) Sectional wall and method of erecting it
CN108203981B (en) System and method for installing steel support in cover and excavation method
CN110093928B (en) Foundation pit supporting structure and earth excavation construction method

Legal Events

Date Code Title Description
A871 Explanation of circumstances concerning accelerated examination

Free format text: JAPANESE INTERMEDIATE CODE: A871

Effective date: 20160606

A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20160606

A975 Report on accelerated examination

Free format text: JAPANESE INTERMEDIATE CODE: A971005

Effective date: 20160623

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20160628

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20160705

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20160712

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: 20160913

R150 Certificate of patent or registration of utility model

Ref document number: 6010070

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R150

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20160915

S111 Request for change of ownership or part of ownership

Free format text: JAPANESE INTERMEDIATE CODE: R313113

R350 Written notification of registration of transfer

Free format text: JAPANESE INTERMEDIATE CODE: R350

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

S111 Request for change of ownership or part of ownership

Free format text: JAPANESE INTERMEDIATE CODE: R313113