JP2005350979A - Cofferdam structure and cofferdam method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an economical cofferdam structure and cofferdam method. <P>SOLUTION: This cofferdam structure 18 is provided with a plurality of separably connected precast panels 20 and installed to surround an underwater structure such as a bridge foundation. The panel 20 is composed of a standard panel 22 and a deformed panel 24. The panel 22 is formed in linear rectangular shape having predetermined width and length, and the panel 24 is formed in bent plate shape with the plane shape bent in a dog-legged-shape. A parallel part of the structure 18 has five panels 22 connected to one another. A polygonal part is formed by connecting four deformed panels 24 and three standard panels 22 alternately. Bolts and nuts 32 are used for connecting the respective panels 22, 24, and the respective panels 22, 24 are separably connected by the fastening structure of the bolts and nuts 32. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a temporary closing structure and a temporary closing method used when repairing an underwater structure such as an existing pier foundation, such as repair and reinforcement.

  The temporary cutoff structure is used when repairing an underwater structure such as a bridge foundation, and a temporary cutoff structure using a precast panel is disclosed in, for example, Patent Document 1.

  The provisional deadline structure disclosed in Patent Document 1 is preferably used in a place where there is an upper limit, and in order to cope with such a restriction, the panel is divided into upper and lower parts at a construction site. This was laminated. However, the temporary closing structure and the temporary closing method having such a configuration have a technical problem that a large cost is required to install and remove the temporary closing structure and a construction period is prolonged.

  Accordingly, the inventors of the present application have developed a temporary closing structure and a temporary closing method that can solve such problems and have already proposed in Patent Document 2. The provisional cutoff structure proposed in Patent Document 2 has a plurality of annular assemblies surrounding the outer periphery of the underwater structure, and is erected on the base portion of the underwater structure. An anchor is installed so as to penetrate vertically therethrough, and a tension force is introduced into the anchor so as to be fixed to the uppermost annular assembly.

  In addition, each annular assembly is obtained by connecting a plurality of precast panel units obtained by dividing an annular body having a predetermined height along the circumferential direction with a vertical sealing material between circumferential ends. A horizontal sealing material is interposed on the upper and lower joint surfaces of the annular assemblies stacked in the vertical direction.

The temporary closing structure having such a configuration can counteract the force in the shearing direction without incurring an increase in cost and lengthening of the construction period, but has technical problems described below. .
Japanese Patent Laid-Open No. 11-21908 Japanese Patent Application No. 2003-279550

  In other words, the provisional deadline structure proposed in Patent Document 2 is designed and manufactured in accordance with the shape and dimensions of the underwater structure to be repaired, such as a bridge foundation, and applied to each site. doing.

  For this reason, the precast panels are made to order for each site, and after the completion of construction, they are basically handled as waste materials, which has been an obstacle to cost reduction.

  The present invention has been made in view of such conventional problems, and the object of the present invention is to make provisional deadlines that can achieve a significant cost reduction by making the precast panel divertable. The object is to provide a structure and a temporary closing method.

  In order to achieve the above-mentioned object, the present invention is installed in a closed cross-sectional shape in which a plurality of precast panels are connected via a water stop member to bend the outer periphery of an underwater structure such as a bridge foundation. In the temporary closing structure used when repairing or reinforcing the underwater structure, the precast panel includes a flat standard panel and a bent plate shape whose plane shape is refracted into a square shape, or a flat surface. A curved plate-like deformed panel having a curved shape, and the standard panel and the deformed panel are detachably connected to form a closed cross-sectional shape.

  In addition, the present invention connects a plurality of precast panels with a water blocking member interposed therebetween, and installs a closed cross-sectional temporary closing structure that surrounds the outer periphery of an underwater structure such as a bridge foundation, In the temporary deadline construction method in which the interior of the temporary deadline structure is drained and the underwater structure is repaired or repaired, the precast panel is refracted into a flat plate-like standard panel and a flat shape. A bent plate-like or curved plate-shaped deformed panel having a curved plane shape, and the standard panel and the deformed panel are detachably connected to form the temporary closing structure having a closed cross-sectional shape. I made it.

  According to the temporary closing structure and the temporary closing method constructed as described above, the plurality of precast panels are a flat standard panel, a bent plate shape whose plane shape is refracted into a square shape, or a curved shape whose plane shape is curved. A plate-shaped deformed panel is provided, and the standard panel and the deformed panel are detachably connected to form a temporary fastening structure with a closed cross-sectional shape. Diversion at the construction site becomes possible.

  A frame that removably supports the lower end side of the precast panel of the temporary closing structure can be installed in advance in the underwater structure.

  According to the temporary closing structure and the temporary closing method according to the present invention, the precast panel can be diverted, so that significant cost reduction can be achieved.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the accompanying drawings.

  1 to 4 show an embodiment of a temporary closing structure and a temporary closing method according to the present invention. The temporary closing structure and the temporary closing method shown in these drawings are applied when repair work such as repair and reinforcement of the bridge 10 that is an underwater structure is performed, and this embodiment shows such an application example. .

  The bridge 10 includes a pier 12 and a footing 14 that is a foundation portion integrally formed at the lower end thereof. The bridge pier 12 has an oval horizontal cross section, and the footing 14 is also formed in an oval shape having a planar shape similar to that of the pier 12, and a part of the lower end thereof is buried in the underwater ground 16. Yes.

  The temporary closing structure 18 of this embodiment includes a plurality of precast panels 20. The temporary closing structure 18 is installed on a frame 26 fixed to the upper surface of the footing 14 so that the lower end side is detachable and surrounds the outer periphery of the bridge pier 12, The drainage is used to create a dry environmental condition on the outer periphery of the pier 12 and to repair or reinforce the pier 12.

  The frame body 26 is formed in the same shape as the temporary closing structure 18 that goes around the outer periphery of the pier 12, and is fixed to the footing 14 by an anchor 28. In addition, a packing is provided in the frame body 26 to contact the lower end of the temporary cutoff structure 18 to ensure water stoppage.

  In the case of the present embodiment, the provisional shut-off structure 18 formed in an oval shape is stacked in three steps so as to surround the outer periphery of the pier 12 and protrude on the water surface. Although not shown in detail, a water-stopping packing is interposed between the temporary closing structures 18 stacked in a step shape.

  Further, the provisional deadline structure 18 stacked in a step shape is fixed by an anchor bolt 30 installed so as to penetrate the upper and lower direction. In this case, a plurality of anchor bolts 30 are installed at predetermined intervals along the shape of the temporary closing structure 18, and each anchor bolt 30 is fixed to the frame body 26 at the lower end side, and the upper end side is the outermost side. A nut 31 is attached to the upper temporary closing structure 18 and fixed.

  In the case of the present embodiment, the temporary closing structure 18 includes a plurality of precast panels 20 that are manufactured in advance by factory production, as shown in FIG. The precast panel 20 includes a standard panel 22 and a deformed panel 24 having the same thickness. In this case, in particular, the deformed panel 24 can have a thickness different from that of the standard panel 22 or can be strengthened by changing a reinforcing means such as a rib depending on a pressure or a pressurized state.

  These precast panels 20 are, for example, flat plates made of steel or reinforced concrete. As shown in detail in FIGS. 3 and 4, the standard panel 22 is a straight line having a predetermined width and length. It is formed in a rectangular shape. The deformed panel 24 has a bent plate shape whose planar shape is refracted into a square shape, and in the present embodiment, the refraction angle is 30 °.

  In the case of the present embodiment, the provisional deadline structure 18 has a polygonal shape similar to an oval covering the outer periphery of the bridge pier 12 on the small judgment surface, as shown in FIG. It has a closed cross-sectional shape including a pair of parallel parts along the side and polygonal parts connected to both ends of the parallel parts.

  In the temporary cutoff structure 18 having such a shape, the parallel parts are formed by connecting five standard panels 22 to each other. Further, the polygonal portion is formed by alternately connecting the four odd-shaped panels 24 and the three standard panels 22.

  The bolts and nuts 32 are used to connect the panels 22 and 24, and the panels 22 and 24 are detachably connected by the fastening structure of the bolts and nuts 32. In addition, the water-proof packing is interposed in the connection part of each panel 22 and 24. FIG.

  In the temporary closing structure 18 thus formed, when the work such as the repair of the bridge pier 12 is completed, when the bolts and nuts 32 are removed, the panels 22 and 24 can be separated. Can be diverted to the site.

  Next, the temporary closing method using the temporary closing structure 18 configured as described above will be described. When repairing the pier 12 or the like, first, as shown in FIG. 1, the frame 26 is formed on the upper surface of the footing 14 in a predetermined shape so as to go around the outer periphery of the pier 12.

  When the frame body 26 is fixed to the footing 14 by the anchor 28, the temporary closing structure 18 is installed so that the lower end side is inserted into the frame body 26. In this case, the temporary closing structure 18 is detachably installed at the lower end side with respect to the frame body 26, and a water-stopping packing is interposed therebetween.

  The temporary closing structure 18 is formed in a closed cross-sectional shape surrounding the outer periphery of the pier 12 by connecting the precast panel 20 including the standard panel 22 and the deformed panel 24 to each other.

  When the oval-shaped temporary fastening structure 18 is formed by the plurality of precast panels 20, in the oval planar shape of the temporary closing structure 18, the parallel parts are formed of 32 standard panels 22 with bolts and nuts 32. Are connected to each other so that they are almost straight.

  In addition, in the polygonal portions on both end sides of the parallel portion, four deformed panels 24 and three standard panels 22 are connected to each other by bolts and nuts 32, and are connected to the parallel portion. Forming part. In this case, a packing for ensuring water-stopping is interposed at the connecting portion between the panels 22 and 24.

  When the temporary cut-off structure 18 for one stage is formed, the temporary cut-off structure 18 on the upper stage is sequentially stacked. At this time, a packing for water stop is interposed between the structures 18. When the predetermined number of temporary cutoff structures 18 are formed, the required temporary cutoff structure 18 can be obtained by attaching the nut 31 to the anchor bolt 30 and fixing it. An internal support 34 and a support jack 36 are installed on the inner side of the constructed temporary closing structure 18 to stabilize the shape and structure.

  When the reinforcement and repair of the pier 12 are completed, the temporary closing structure 18 is disassembled and removed. In this case, the panels 22 and 24 can be separated by removing the bolts and nuts 32. It can be used as it is for other construction sites.

  Now, according to the temporary closing structure and the temporary closing method constructed as described above, the plurality of precast panels 20 include a flat standard panel 22 and a bent plate-shaped deformed panel 24 whose planar shape is refracted into a square shape. The standard panel 22 and the deformed panel 24 are detachably connected to form the temporary fastening structure 18 having a closed cross-sectional shape. When the standard panel 22 and the deformed panel 24 are separated after use, Diversion at the construction site becomes possible.

  5 and 6 are modifications of the deformed panel 24 shown in the first embodiment. FIG. 5 shows a deformed panel 24a having a refraction angle of 45 °, and FIG. 6 shows the refraction angle. A deformed panel 24b with 60 ° is shown.

  These odd-shaped panels 24a and 24b are detachably connected to the standard panels 22a and 24b via bolts and nuts 32, and are used when forming a temporary closing structure having a closed cross-sectional shape in the same manner as in the above embodiment. The same effects as those in the above embodiment can be obtained.

  Each of the above-mentioned deformed panels 24, 24a, 24b can be combined with the standard panels 22, 22a, 22b independently to form a temporary closing structure, and a combination of any two deformed panels can be formed. It is also possible to combine them, or a combination of all the odd-shaped panels and a standard panel.

  FIGS. 7 to 9 show another embodiment of the temporary closing structure and the temporary closing method according to the present invention. The same or corresponding parts as those in the above embodiment are designated by the same reference numerals and the description thereof will be given. While omitting, only the feature points will be described in detail below.

  The temporary closing structure and the temporary closing method shown in these drawings are applied when repair work such as repair and reinforcement of the bridge 10c, which is an underwater structure, is performed as in the above embodiment. The bridge 10c includes a bridge pier 12c and a footing that is a foundation portion integrally formed at the lower end thereof, and the horizontal section of the bridge pier 12c is rectangular.

  In the case of the present embodiment, the temporary closing structure 18c surrounding the outer periphery of the pier 12c is a precast product having the same thickness, which is a substantially rectangular shape having a closed cross-sectional shape, and is a standard panel 22c and a modified panel 24c. It consists of and.

  The standard panel 22c is formed in a linear rectangular shape having a predetermined width and length as in the above embodiment. In the case of the present embodiment, the deformed panel 24c is a curved plate having a curved planar shape, and has a central angle of 45 °.

  Such a deformed panel 24c is arranged so that a pair is connected to each corner, and the panels 22c and 24c can be separated via bolts and nuts 32 as in the above embodiment. Connected.

  Even if the standard panel 22c and the modified panel 24c having such a configuration are used, the same effects as those of the above-described embodiment can be obtained. Note that the odd-shaped panel 24c shown in FIG. 10 does not need to connect two panels having a central angle of 45 °. For example, a deformed panel having a central angle of 90 ° may be used.

  In the above embodiment, the case where the provisional deadline structure 18 is stacked and installed on the outer periphery of the pier 12 is exemplified. However, the implementation of the present invention is not limited to this, for example, the provisional deadline structure. The body 18 may be one-stage.

  Further, in the above embodiment, the case where the present invention is applied to the modification of the bridge pier 12 having an oval or rectangular cross section is illustrated, but the application of the present invention is not limited to such a shape. It can also be applied to underwater structures such as a square cross section.

  The temporary closing structure and the temporary closing method according to the present invention can be effectively used for repair work of a pier because the precast panel can be diverted to other construction sites.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall explanatory view showing one embodiment of a temporary closing structure and a temporary closing method according to the present invention. It is a principal part horizontal sectional view of FIG. It is a principal part expansion perspective view of FIG. FIG. 4 is a top view of FIG. 3. It is a top view which shows the modification of the deformed panel shown in FIG. It is a top view which shows another modification of the deformed panel shown in FIG. It is a horizontal sectional view showing other examples of the temporary closing structure and temporary closing method according to the present invention. It is a principal part expansion perspective view of FIG. FIG. 9 is a top view of FIG. 8.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Bridge 12 Bridge pier 14 Footing 18 Temporary cutoff structure 20 Precast panel 22, 22a, 22b, 22c Standard panel 24, 24a, 24b, 24c Deformed panel 32 Bolt nut

Claims (3)

A plurality of precast panels are connected via a water-stopping member and installed in a closed cross-sectional shape that surrounds the outer periphery of underwater structures such as bridge foundations. In the temporary deadline structure used when performing
The precast panel includes a flat standard panel, a bent plate shape whose planar shape is refracted into a square shape, or a curved plate-shaped deformed panel whose planar shape is curved,
The standard panel and the deformed panel are detachably connected to form a closed cross-sectional structure. A plurality of precast panels are connected via a water stop member to install a closed cross-sectional temporary closing structure that surrounds the outer periphery of an underwater structure such as a bridge foundation. In the temporary closing method of draining the interior and repairing the above-mentioned underwater structure, such as repair, reinforcement,
The precast panel includes a flat standard panel, a bent plate shape whose planar shape is refracted into a square shape, or a curved plate-shaped deformed panel whose planar shape is curved,
The temporary panel construction method, wherein the standard panel and the deformed panel are detachably connected to form the temporary panel structure having a closed cross-sectional shape.   The temporary closing method according to claim 2, wherein a frame that removably supports a lower end side of the precast panel of the temporary closing structure is installed in advance in the underwater structure.

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