JP3928226B2 - Temporary deadline structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a temporary closing structure, and more particularly to a temporary closing structure suitable for repairing an underwater structure, such as repair.
[0002]
[Prior art]
Damages such as damage and collapse of structures due to earthquakes are not limited to structures on land, but extend to rivers and underwater structures built on the sea, such as bridge foundations and revetments.
[0003]
When such an underwater structure is damaged, it is necessary to take seismic reinforcement measures as with land structures. When implementing seismic reinforcement for underwater structures in rivers and seas, it is necessary to remove water from the surroundings of the structure and work in a dry environment. The construction method is generally adopted.
[0004]
A typical construction state of this double deadline construction method is shown in FIG. The double deadline method shown in the figure is an application example in the case where the reinforcement repair work of the pier 1 is performed, and the temporary deadline 3 is constructed so as to surround the outer periphery of the footing 2.
[0005]
The temporary closing work 3 is composed of inner and outer walls 3a and 3b formed by driving sheet piles in the bottom bottom of the footing 2 and a plurality of tie rods 3c connecting the inner and outer walls 3a and 3b. Has been.
[0006]
In this temporary closing work 3, by filling the inner and outer walls 3a, 3b with the middle earth and sand 4 to ensure water-stopping and stability, it is in a dry state by eliminating the water in the inner wall 3a, Renovation work is performed in which the reinforcement work 5 is applied to the outer periphery of the pier 1.
[0007]
However, such a conventional double deadline method has the following technical problems.
[0008]
[Problems to be solved by the invention]
In other words, the double deadline method described above involves placing and removing sheet piles, which requires time and labor for assembly and disassembly, and the construction and removal costs for temporary structures account for a large percentage of the total construction cost. was there.
[0009]
In addition, as shown in FIG. 10, when placing a sheet pile under the beam above the bridge, it becomes difficult to construct a long object due to the clearance. There was also a problem that it took more time for construction.
[0010]
Furthermore, the double deadline method occupies a large area for a long period of time, which hinders running water and water traffic, and makes it difficult to complete construction throughout the year.
[0011]
Furthermore, when the middle stuffing sand 4 is filled, there is a possibility that a water pollution problem may occur when the sand is introduced and removed. Accordingly, the present inventors have developed a temporary closing method capable of solving such problems and have already proposed it in Japanese Patent Application No. 9-178603.
[0012]
The construction method according to this application facilitates assembly and disassembly by using a precast panel and solves the problem of water pollution. However, according to the subsequent examination, there are the following problems.
[0013]
In the temporary closing method according to the above application, the temporary closing work in which the precast panels are assembled in a laminated state is placed on the upper portion of the foundation portion, and these are integrated by introducing a prestressing force using a fixing anchor.
[0014]
However, in such a configuration, if the top end surface of the foundation portion is inclined, or the top end surface is uneven, or the embedded metal fitting protrudes from the top end surface, the adhesion to the water-stopping material There was a problem that a good water stop effect could not be obtained.
[0015]
This invention is made | formed in view of such a conventional problem, Comprising: The place made into the objective is to provide the temporary closing structure which can obtain the favorable water stop effect.
[0016]
[Means for Solving the Problems]
In order to achieve the above-described object, the present invention is to repair and reinforce the underwater structure by surrounding the outer periphery of an underwater structure such as a bridge foundation with a temporary closing work and draining the inside of the temporary closing work. In the temporary closing structure for repairing, the temporary closing work includes a plurality of precast panels laminated in a cylindrical shape on the outer periphery of the underwater structure with a sealant interposed between the circumferential and vertical joints. It is constructed by installing the laminated precast panel on the foundation part of the underwater structure and integrating it with the foundation part by a plurality of anchors fixed at one end to the foundation part. There is a temporary cutoff structure in which a water mortar layer is provided between a lower end surface of the first-stage precast panel laminated on the foundation portion and an upper end surface of the foundation portion, and the precast panel is , Zhou A skin plate that defines an outer peripheral surface in a state of being connected in a direction, a plurality of vertical beams that are suspended from and fixed to a circumferential edge of the skin plate, and a vertical edge of the skin plate. A plurality of transverse beams fixed along the inner surface and formed in an annular shape in a connected state, on the lower surface of the transverse beam of the precast panel disposed in the first stage, along the outer periphery of the foundation portion An extending skirt,
The water-stopping mortar layer is formed by filling mortar into a space defined by the cross beam, the skirt portion, and the outer peripheral surface of the foundation portion .
According to the temporary closing structure constructed in this way, the precast panel can be produced in the factory in advance, so that a high-quality panel can be obtained, assembly and disassembly are simplified, and water pollution problems do not occur. Since the mortar layer for water stop is provided between the lower end surface of the first-stage precast panel placed on the base portion and the upper end surface of the base portion, the top end surface of the base portion is inclined, uneven, Even if there is a protrusion of the embedded metal fitting, it is possible to ensure water-stopping between the two.
The water-stopping mortar layer is provided with a skirt portion extending along the outer periphery of the foundation portion on the lower surface of the transverse beam of the precast panel arranged in the first stage, and the transverse beam, the skirt portion, and the outer peripheral surface of the foundation portion. Since it forms by filling the mortar in the space which was formed, it can form reliably.
A lower end of the skirt portion penetrates into the water bottom ground, and a flexible member is provided on the lower surface side of the transverse beam so that the distal end side is in sliding contact with the upper surface of the foundation portion and separates the inner side of the space. Can do. According to this structure, the outflow of the material for forming the mortar layer can be prevented.
When the precast panel is connected in the circumferential direction, the vertical beam can be provided with a hinge structure part formed by a concave-convex fitting that allows horizontal movement of the connected precast panel. According to this configuration, since the shape of the hinge structure portion is simple, processing can be easily performed.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the accompanying drawings. 1 to 9 show an embodiment of a temporary closing structure according to the present invention. The provisional deadline structure shown in the figure illustrates a case where it is applied when repair work such as repair and reinforcement of the bridge 10 that is an underwater structure is performed.
[0018]
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 a substantially circular horizontal cross section, and the footing 14 has a circular planar shape, and a part of the lower end thereof is buried in the water bottom ground 16.
[0019]
The temporary closing work 18 of this embodiment is installed so as to surround and flex the outer periphery of the pier 12, and is used for draining the water on the inner side to create a dry environmental condition on the outer periphery of the pier 12. .
[0020]
The temporary closing work 18 is a concentric structure having the same shape as the pier 12, and includes a plurality of precast panels 20 having substantially the same configuration divided along the vertical direction and the circumferential direction of the pier 12 as main constituent members. It is said. A ring-shaped support work 42 is interposed between the temporary closing work 18 and the pier 12 assembled in a cylindrical shape.
[0021]
In the case of the present embodiment, each precast panel 20 has a shape in which a circle is divided into four at equal angular intervals. As shown in detail in FIG. 3, a skin plate 20a and a plurality of vertical beams 20b are provided. And a pair of horizontal beams 20c and a plurality of vertical ribs 20d.
[0022]
The skin plate 20a is bent in an arc shape, and when the precast panel 20 is connected in the circumferential and vertical directions, the skin plate 20a becomes a cylindrical shape and separates the outer peripheral surface of the temporary closing work 18.
[0023]
The vertical beams 20b are disposed at both ends of the skin plate 20a in the circumferential direction and at the center thereof, and are fixed in the vertical direction of the inner surface of the skin plate 20a. On the outer peripheral surface of the pair of vertical beams 20b fixed to both ends of the skin plate 20a, a concave portion 20e and a convex portion 20f constituting a hinge structure portion described later are provided along the vertical direction.
[0024]
The pair of horizontal beams 20c is formed of an arc-shaped flat plate, and is fixed to the vertical end surfaces of the skin plate 20a and the vertical beam 20b. When the precast panel 20 is connected in the circumferential vertical direction, the cross beam 20c becomes a ring and reinforces the strength of the temporary closing work 18. In addition, this horizontal beam 20c is not restricted to a pair, You may provide in the middle of the up-down direction of the skin plate 20a.
[0025]
Further, insertion holes 20g of anchor bolts 28 for securing a mortar filling space to be described later are formed through each horizontal beam 20c below the precast panel 20 arranged in the first stage. In addition, the part shown with the code | symbol 20h in FIG. 3 is the insertion hole of the volt | bolt used when connecting the precast panel 20 to an up-down direction.
[0026]
The vertical ribs 20d are on the inner peripheral surface side of the skin plate 20a, are extended and fixed in the vertical direction, and reinforce the strength of the skin plate 20a. Note that the vertical rib 20d is not always necessary, for example, when the thickness of the skin plate 20a is increased.
[0027]
The ring-shaped supporter 42 is installed in a stepped manner at a predetermined interval in the vertical direction of the temporary closing work 18, and as shown in detail in FIGS. 4 and 5, an inner ring material that abuts the outer peripheral surface of the pier 12. 42a, an outer ring member 42b that comes into contact with the inner surface of the longitudinal beam 20b of the precast panel 20 that is assembled in an annular shape, and a plurality of cut beams 42c that are installed between the inner and outer ring members 42a and 42b.
[0028]
Like the precast panel 20, the ring-shaped supporter 42 thus configured is divided in the circumferential direction, manufactured in advance as a precast product, and assembled into an annular shape after being transported to the construction site.
[0029]
In this case, the inner and outer diameters of the inner and outer ring members 42a and 42b are designed in advance according to the outer diameter of the pier 12 and the inner diameter of the vertical beam 20b of the temporary closing work 18, respectively. If there is a gap between 42a, 42b and the pier 12 or the vertical beam 20b, a gap adjusting member 44 such as a wedge or a bag body filled with high-pressure gas is inserted into the gap to bring them into close contact with each other.
[0030]
Next, a procedure for assembling the temporary closing work 18 using the precast panel 20 having the above configuration will be described. When assembling the temporary cutoff line 18, the precast panel 20 and the ring-shaped support work 42 are manufactured in a production yard near the repair site of the bridge 10 and transported to the vicinity of the bridge 10.
[0031]
On the other hand, as shown in FIGS. 6 and 7, anchor bolts 28 whose lower ends penetrate into and are fixed to the footing 14 are planted in the footing 14 at predetermined intervals in the circumferential direction.
[0032]
As shown in FIG. 6, the precast panel 20 and the ring-shaped supporter 42 that have been transported are first assembled in an annular shape and installed on the outer periphery of the pier 12. Supported.
[0033]
When the installation of the ring support 42 is completed, the outer ring material 42b is used as a guide, and one stage of the precast panel 20 is connected in the circumferential direction to the outer ring side 42b and assembled.
[0034]
FIG. 8 shows a connected state of the precast panel 20 at the dividing position. In the connected state shown in the figure, a water stop sealing material 34, specifically, a water stop rubber plate is interposed between the longitudinal beams 20b adjacent to each other in the circumferential direction. The bolt 36 is inserted into the through-hole, and the nut 38 is screwed.
[0035]
The water stop sealing material 34 is disposed on both ends of the concave and convex portions 20e, f provided on the vertical beam 20b. Each longitudinal beam 20b arranged at the end in the circumferential direction of the precast panel 20 is provided with recesses and projections 20e, f that can be fitted to each other. The concave and convex portions 20e and f constitute a hinge structure when the longitudinal beams 20b adjacent in the circumferential direction are connected.
[0036]
In this case, the through hole into which the bolt 36 is inserted is formed to be longer than the diameter of the bolt 36 in the horizontal direction so that the precast panel 20 connected by the bolt 36 and the nut 38 can move in the horizontal direction. It has become.
[0037]
When the four precast panels 20 are connected in the circumferential direction by the connection of the bolts 36 and the nuts 38 to form an annular portion for one step, the assembled portion is sunk and then the same as the upper step side. By the method, the precast panels 20 are sequentially laminated, and the dividing positions are similarly connected by bolts and nuts 36 and 38.
[0038]
In addition, the member shown with the code | symbol 40 in FIG. 8 is the backing plate provided in one of the one longitudinal beam 20b connected, Comprising: This backing plate 40 assembles the panel 20 to the circumferential direction. Use it as a guide.
[0039]
When the precast panel 20 is assembled, the precast panel 20 is supported by a floating platform 62 such as a floating body or a jetty as shown in FIG. 6, and the ring-shaped support 42 is shown in FIG. It is used as a guide when assembling each precast panel 20 in an annular shape.
[0040]
At this time, as shown in FIG. 9, between the cross beams 20c of the precast panel 20 positioned in the vertical direction, a seal member 35 is interposed, and the cross beams 20c are fastened with bolts and nuts.
[0041]
Assembling of the precast panel 20 as described above is continued, and when the first-stage precast panel 20 reaches the vicinity of the upper surface of the footing 14, as shown in FIG. 7, anchor bolts 28 embedded in the footing 14. Is inserted into the insertion hole 20g of the horizontal beam 20c, and the anchor bolt 28 is fixed by welding or screwing a nut to the horizontal beam 20c.
[0042]
At this time, the anchor bolt 28 is fixed at a position where the lower surface of the horizontal beam 20c is spaced a predetermined distance upward from the upper surface of the footing 14 to ensure the filling interval of the water-stopping mortar layer 24.
[0043]
The still water mortar layer 24 is fixed to the lower surface side of the cross beam 20c of the first-stage panel 20, and is defined by the skirt portion 26 extending downward along the side surface of the footing 14 and the upper and side surfaces of the footing 14. It is formed by filling mortar in the space.
[0044]
The skirt portion 26 is provided only at the first stage of the panel 20 placed on the footing 14. When the precast panel 20 is assembled in an annular shape, the skirt portion 26 is spaced apart from the side surface of the footing 14 by a predetermined interval. The side is surrounded by a ring.
[0045]
In this case, a part of the lower end side of the skirt portion 26 is installed so as to penetrate into the water bottom ground 16, and the backfill soil is covered on the ground 16 as necessary, so that the mortar filled in the space can be obtained. Prevent outflow. A reinforcing plate 27 is fixed on the back side of the skirt portion 26.
[0046]
Further, in order to prevent the filled mortar from flowing out inward, a flexible member 30 such as a rubber plate is fixed inside the cross beam 20c, and the leading end side of the flexible member 30 is attached with a string or the like. The tip of the flexible member 30 is bent along the upper surface of the footing 14 by pulling inward.
[0047]
The mortar for forming the water-stopping mortar layer 24 is injected through an injection pipe 32 provided so that one end penetrates the cross beam 20c. When the water stop mortar layer 24 is formed, the assembly operation of the precast panel 20 is resumed, and when the predetermined number of stages of the precast panel 20 are stacked and connected, the ring-shaped support 42 is interposed between the precast panel 20 and the pier 12. Is installed.
[0048]
In the case of the present embodiment, the installation position of the ring-shaped support 42 is such that the cut beam 42c corresponds to the circumferential dividing position of the precast panel 20, that is, the position of the vertical beam 20c, as shown in FIG. Set to
[0049]
Moreover, the ring-shaped support work 42 is installed in multiple stages in the vertical direction corresponding to the size and height of the temporary closing work 18 to be constructed. When the support work 42 is installed and the stability of the laminated temporary cut-off work 18 is ensured, the temporary cut-off work 18 having a water stop structure in which the precast panel 20 and the footing 14 connected to each other are integrated is completed. To do.
[0050]
When the temporary closing work 18 is completed, the internal water is drained to create a dry work space around the pier 12 and the repair work such as reinforcement of the pier 12 and the footing 14 is performed. By introducing water into the deadline 18 and performing the reverse operation of the assembly, the temporary deadline 18 is disassembled and removed.
[0051]
Now, according to the provisional deadline structure configured as described above, the precast panel 20 which is the main part of the provisional deadline 18 is produced in advance in the factory, so that a high-quality one can be obtained and the underwater structure can be obtained. After transporting the object to the repair site, it is constructed in an annular shape with the sealing members 34 and 35 interposed between the circumferentially divided portion and the vertically joined portion, and fixed to the footing 14 with the anchor bolt 28, so There is very little on-site work such as driving, and the temporary closing work 18 can be constructed easily and quickly.
[0052]
In addition, it can be easily removed after renovation work, making it suitable for rapid construction. Furthermore, in the case of the present embodiment, the temporary closing work 18 is constructed on the upper surface side of the footing 14 and is different from the double structure as in the conventional temporary closing work. Since it is smaller than the size of the water and does not occupy a large area, it does not hinder water traffic. Moreover, since the temporary closing work 18 of the present invention does not require the filling earth and sand, the water quality is not polluted.
[0053]
In the case of the present embodiment, in addition to the above-described effects, a water-stopping mortar layer 24 is provided between the lower end surface of the first stage precast panel 20 placed on the footing 14 and the upper end surface of the footing 14. Since it is provided, even if the top end surface of the footing 14 has an inclination, unevenness, protrusion of the embedded metal fitting, etc., it is possible to ensure water-stopping between the two.
[0054]
Furthermore, in the case of the present embodiment, when the precast panel 20 is connected in the circumferential direction, concave and convex portions 20e, f are provided that serve as a hinge structure part that allows horizontal movement of the connected precast panel 20. Therefore, it is possible to prevent bending stress from acting on the temporary closing work 18 when an offset load is applied to the temporary closing work 18.
[0055]
In this case, the concave / convex fitting hinge structure is simple in shape and easy to process, which is very advantageous in terms of economy.
[0056]
In addition, in the said Example, although the temporary closing work 18 of circular cross section was illustrated, implementation of this invention is not limited to this shape, For example, it applies also to polygonal shape, an ellipse shape, and an ellipse shape. be able to.
[0057]
Further, the number of divisions in the circumferential direction of the precast panel 20 is not limited to four, and can be appropriately selected according to the size of the temporary closing work to be constructed.
[0058]
【The invention's effect】
As described above in detail in the embodiments, according to the temporary fastening structure according to the present invention, the following operational effects can be obtained.
(1). The precast panel can be manufactured in a factory, and therefore, high-quality panels can be obtained and can be diverted, which is advantageous in terms of economy.
(2). Since it is a single structure and is compact, it is suitable for rapid construction and does not require a large area, so it is economical and does not hinder water traffic.
(3). The water-stopping mortar layer formed between the lower end surface of the Fourier cast panel and the upper end surface of the foundation part has fluidity until it hardens. Therefore, the panel and the base portion are in close contact with each other, and a sufficient water stop effect can be obtained.
[Brief description of the drawings]
FIG. 1 is a half sectional view of an assembled state of a temporary cutoff structure according to the present invention.
FIG. 2 is a top view of FIG.
FIG. 3 is a perspective view of a precast panel used in the temporary cutoff structure shown in FIG.
4 is an enlarged view of a main part of FIG.
FIG. 5 is an enlarged view of a part A in FIG. 1;
FIG. 6 is an explanatory view of an assembled state of the temporary closing structure according to the present invention.
7 is an enlarged view of a portion B in FIG.
FIG. 8 is an enlarged view of part C in FIG. 2;
FIG. 9 is an enlarged view of a portion D in FIG. 1;
FIG. 10 is an explanatory plan view and a cross-sectional view showing an example of a conventional double deadline method.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Bridge 12 Bridge pier 14 Footing 18 Temporary cut-off work 20 Precast panel 20a Skin plate 20b Vertical beam 20c Horizontal beam 20d Vertical rib 24 Water stop mortar layer 26 Skirt part 28 Anchor bolt 32 Injection pipe 34 Water stop seal material 35 Seal material 42 Ring shape Support work

Claims (3)

In the temporary closing structure that renovates the underwater structure, such as repairing and reinforcing the underwater structure by surrounding the outer periphery of the underwater structure such as a bridge foundation with a temporary closing work, draining the inside of the temporary closing work,
The temporary closing process includes a plurality of precast panels that are laminated in a cylindrical shape on the outer periphery of the underwater structure, with a sealant interposed between the circumferential and vertical joints,
The laminated precast panel is installed on the foundation part of the underwater structure, and is constructed by integrating the foundation part with a plurality of anchors fixed at one end to the foundation part,
A temporary fastening structure in which a water-stopping mortar layer is provided between the lower end surface of the first stage precast panel and the upper end surface of the foundation portion laminated on the foundation portion,
The precast panel includes a skin plate that defines an outer peripheral surface in a state of being connected in the circumferential direction, and a plurality of vertical beams that are vertically fixed to the circumferential edge of the skin plate,
A plurality of transverse beams which are at the edge in the vertical direction of the skin plate and fixed along the inner surface thereof and formed in an annular shape in a connected state;
A skirt portion extending along the outer periphery of the foundation portion is provided on the lower surface of the transverse beam of the precast panel disposed in the first stage,
A temporary fastening structure, wherein the water-stopping mortar layer is formed by filling mortar into a space defined by the cross beam, the skirt portion, and the outer peripheral surface of the foundation portion . A lower end of the skirt portion penetrates into the water bottom ground, and a flexible member that separates the inner side of the space is provided on the lower surface side of the transverse beam, with the tip side slidingly contacting the upper surface of the foundation portion. The temporary closing structure according to claim 1. The temporary beam according to claim 1, wherein the vertical beam is provided with a hinge structure portion including a concave-convex fitting that allows horizontal movement of the connected precast panel when the precast panel is connected in the circumferential direction. Deadline structure .

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