JPH1054037A - Coffering method and steel structural body therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coffering method having good execution efficiency without using a steel sheet pile. SOLUTION: A plurality of arc-shaped corrugated sheets are connected in the circumferential direction on a barge adjacent to a bridge pier 11, first of all, only one stage of corrugated pipe 18a is constituted, the following one stage of corrugated pipe 18b is constituted in a state to hang up the corrugated pipe 18a with a lifting machine, and then, both pipes 18a and 18b are connected to constitute an outside corrugated pipe 18, for example, consisting of six stages by repeating the procedure mentioned above. For example, an inside corrugated pipe 20 of one stage is constituted so as to oppose it to the inside of the lowest stage section 18f of the outside corrugated pipe 18, and both pipes 18 and 20 are connected with joint members 21 to constitute a partial double cylinder structural body 22. Then, the partial double cylinder structural body 22 on the barge is lowered and is installed on the foundation 13, and then, underwater concrete is placed between the outside corrugated pipe 18 and inside corrugated pipe 20. After the concrete is solidified, water in the outside corrugated pipe 18 is drained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deadline method suitable for reinforcing existing underwater legs such as existing underwater bridge piers and the like, and a steel structure used for the deadline method.

[0002]

2. Description of the Related Art For example, in the case of constructing a pier underwater, in order to enable the construction work, an appropriate range surrounding a construction site is subjected to a deadline, and water is drained from the inside. Generally, this kind of deadline method employs a deadline method of driving a steel sheet pile. The deadline method using steel sheet piles has good workability. For example, when reinforcing existing underwater bridge piers, the bridge girder already exists, so secure the upper space necessary for driving steel sheet piles. In some cases, the deadline method using steel sheet piles cannot be adopted. In addition, the method of driving steel sheet piles cannot be adopted in some cases due to the hard ground or noise problems in urban areas.

As a deadline method applicable in such a case, as shown in FIG. 13, an inner cylinder A made of a liner plate and an outer cylinder B made of a corrugated pipe previously assembled on land are installed on a base G. Then, a filling material C such as earth and sand is charged and filled between the installed inner cylindrical body A and the outer cylindrical body B, and then concrete or the like is poured on the ground G outside the base B 'of the outer cylindrical body B. A method of performing the consolidation D has been proposed (see Japanese Utility Model Publication No. 57-23553). In the drawings, E is a structure such as a pier.

[0004]

The above conventional method does not use steel sheet piles, so that there is no problem of an upper space necessary for driving the steel sheet piles, a problem of hard ground, a problem of noise, and the like. However, since it is necessary to install the double cylinders A and B, and it is necessary to charge and fill the filling material C,
Construction work is extremely complicated. In addition, this is a temporary deadline structure, and the temporary deadline structure will be removed after the construction is completed. However, even if it is easy to remove because there is no driving part, the removal work of this temporary deadline structure is also complicated. It is.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional drawbacks, and is a construction method which does not use steel sheet piles, has good workability, and is easy to remove after completion of construction, and a deadline method. An object of the present invention is to provide a steel structure for a construction method.

[0006]

In order to solve the above-mentioned problems, a closing method according to the present invention comprises connecting a plurality of arc-shaped corrugated sheets in a horizontal circumferential direction and a vertical direction to form an outer corrugated pipe comprising a plurality of stages. And forming a plurality of arcuate corrugated sheets having a smaller curvature than the corrugated sheet of the outer corrugated pipe in the circumferential direction or in the circumferential direction and vertically so as to face at least the inner surface of the lowermost step of the outer corrugated pipe. Connect in the direction 1
A step of forming a partially double cylindrical structure by forming a step or a plurality of steps of the inner corrugated pipe shorter than the outer corrugated pipe and connecting the inner corrugated pipe and the outer corrugated pipe by a connecting member; Lowering the partial double-cylinder structure and installing it on the bottom of the water; then, casting underwater concrete between the outer corrugated pipe and the inner corrugated pipe of the partial double-cylinder structure; And, after hardening the concrete, draining the water in the outer corrugated pipe.

A second aspect of the present invention is to apply the deadline method of the first aspect to an existing underwater leg reinforcing work for reinforcing an existing underwater leg.

A third aspect of the present invention is a steel structure used in the closing method according to the first or second aspect, wherein a plurality of arcuate corrugated sheets are connected in a horizontal circumferential direction and a vertical direction. The outer corrugated pipe having a plurality of steps and a plurality of arcuate corrugated sheets having a smaller curvature than the corrugated sheet of the outer corrugated pipe are circumferentially arranged so as to face at least the inner surface of the lowermost step of the outer corrugated pipe. Or one or more inner corrugated pipes shorter than the outer corrugated pipe connected to the outer corrugated pipe via a connecting member and configured to be connected in the circumferential and vertical directions. It is characterized by the following.

[0009]

FIG. 1 is a block diagram showing an embodiment of the present invention.
This will be described with reference to the embodiment shown in FIGS. This embodiment is applied to an existing underwater pier reinforcement work for reinforcing an existing underwater pier. In FIG. 1, reference numeral 11 denotes a pier to be reinforced, 12 denotes a bridge girder, 13 denotes an underwater foundation, and 14 denotes a water surface. The pier 11 is reinforced, for example, with a thickness of about 10 mm around the existing pier 11 with a gap of about 30 mm between the pier 11 and the outer peripheral surface thereof.
The front and rear steel plates are rolled up, the gap is filled with mortar or an adhesive, and concrete is rolled up in a submerged portion outside the steel plate with a thickness of, for example, less than 500 mm.

When performing such a reinforcement work, it is necessary to perform a deadline for draining water in order to perform the work. For this purpose, the deadline method according to one embodiment of the present invention is employed. Figure 1 shows the initial stage.
The barge 15 is floated adjacent to the pier 11 and used as a work platform. Then, on this barge 15, first, a plurality of arc-shaped corrugated sheets 17 are connected in a horizontal circumferential direction to form a single-stage corrugated pipe 18a. Next, as shown in FIG. 2, the one-stage corrugated pipe 18a is lifted by a wire 16 by a lifting machine (not shown), and a plurality of arc-shaped corrugated sheets 17 are placed below the corrugated pipes 17 in a horizontal circumferential direction. To the one-stage corrugated pipe 18b
Is configured. Next, the first corrugated pipe 18a is lowered, wrapped around the upper edge of the lower corrugated pipe 18b, and the upper and lower corrugated pipes 18a, 18 are bolted.
8b. The arcuate corrugated sheet 17
The connection procedure is general, and details thereof are shown in FIG. As shown in the figure, the arc-shaped corrugated sheet 17 is formed by corrugating a steel plate, making mounting holes at both ends in the sheet width direction (vertical direction in the drawing) and both ends in the longitudinal direction, and having a predetermined curvature. Which is curved,
The connection between the corrugated sheets 17 is performed by overlapping the edge portions in the sheet width direction or the longitudinal direction, inserting the bolt 25 into the mounting hole of the overlapping portion, screwing a nut, and tightening. Although not shown in the drawings, packing is interposed at necessary places such as connecting portions between the corrugated sheets 17 so as to stop water. Also, the corrugated pipe 18a
Although details of the hoist that lifts etc. are omitted, a method of attaching a hoisting mechanism to the bridge girder 12 side, a method of using a work boat equipped with a hoist, a method of using a land crane vehicle near the quay, Other appropriate methods can be adopted.

By repeating the above operation, for example, as shown in FIG. 3, one-stage corrugated pipes 18a, 18b, 1
An outer corrugated pipe 18 composed of six stages 8c, 18d, 18e and 18f is constructed. In order to reinforce the outer corrugated pipe 18, for example, a reinforcing ring formed by fitting a steel material having an I-section to the inner surface of the cylindrical outer corrugated pipe 18 is provided at appropriate intervals in the vertical direction on the inner surface of the outer corrugated pipe 18. Should be fixed by welding.

Next, as shown in FIG. A plurality of arcuate corrugated sheets 19 having a smaller curvature than the corrugated sheet 17 of the outer corrugated pipe 18 are connected in the circumferential direction so as to face the inner surface of the lowermost portion 18f of the outer corrugated pipe 18, for example, by one step. The inner corrugated pipe 20 is connected to the inner corrugated pipe 20 and the lowermost portion 18f of the outer corrugated pipe 18 by a connecting member 21 to form a partially double cylindrical structure (steel structure) 22. Is configured. FIG. 7 is a plan view showing the partial double-cylinder structure 22 formed on the barge 15.

[0013] As shown in FIG.
A vertical angle member 21a bolted to the outer surface of the lowermost portion 18f of the outer corrugated pipe 18, and the outer corrugated pipe 18 and the inner side extending from the inner surface of the outer corrugated pipe 18 toward the center at the lower end of the lowermost portion 18f. A horizontal angle member 21b which is passed between the corrugated pipe 20 and is fixed to both the bolts 18 and 20 by bolts, and an oblique angle member 21 which connects between the angle members 21a and 21b.
c. In the embodiment, for example, as shown in FIG.
This connecting member 21 is provided at a location.

Next, as shown in FIG. 4, the barge 15 is moved away from the pier 11 so that the outer corrugated pipe 18 is bent, and then the partial double-cylinder structure 22 is lowered to form a foundation for the pier 11. 13.

Underwater concrete is cast between the outer corrugated pipe 18 and the inner corrugated pipe 20 installed on the foundation 13, but the deadline structure (partial double-cylinder structure in which the underwater concrete is cast) is applied by buoyancy. Body 2
As a countermeasure against buoyancy to prevent 2) from moving, as shown in FIG. 9, an anchor (or a reinforcing bar) 31 is provided for connecting the foundation 13 and a concrete to be poured underwater described later. In addition, the reinforcing steel 32 arranged in the circumferential direction is connected to the anchor 31.
Weld to and arrange reinforcement.

Further, as a countermeasure for preventing the underwater concrete from flowing out between the inner corrugated pipe 20 and the outer corrugated pipe 18 as shown in FIG. 9, for example, as shown in FIG. Foundation 13 at lower end of pipe 20
Sealing material 3 such as a rubber belt for closing the gap with the upper surface
3 is attached. In this case, the seal member 33 may be attached to the corrugated pipes 18 and 20 with bolts, and the base 13 may be attached with a dry bit, for example.

Next, as shown in FIG. 5, underwater concrete is poured between the outer corrugated pipe 18 and the inner corrugated pipe 20. After the concrete is cured, the inside of the outer corrugated pipe 18 is drained, but the underwater concrete 24 ensures that the lower end of the outer corrugated pipe 18 is stopped. As described above, the pier 1
It is possible to perform the first reinforcement work.

After the reinforcement work of the pier 11 is completed, the portion other than the lowermost portion 18f of the outer corrugated pipe 18 (corrugated pipes 18a, 18b, 18c, 1 in the illustrated example).
8d and 18e) can be easily removed by removing the bolt at the connection with the lowermost step 18f. Therefore, the removed ones can be reused in other construction deadlines and are economical. The lowermost portion 18f, the inner corrugated pipe 20, and the concrete 24 cast between them can be removed, but may be left without being removed.

As shown in FIG. 10, the present invention can be applied to a case where the work is carried out on a foundation 13 'having an inclined upper surface.
In the illustrated example, a sealing material 33 using a rubber belt is used as the means for preventing underwater concrete from flowing out, as described above.

As a countermeasure for preventing outflow of underwater concrete, sandbags 34 may be arranged at the lower ends of the inner corrugated pipe 18 and the outer corrugated pipe 20, as shown in FIG. If the foundation has an inclination, the gap at the lower end of the outer corrugated pipe 18 becomes particularly large, so that the sandbag 3
4 is effective. It is more effective to arrange the sandbag 34 on the sealing material 33 as shown in FIG.

In the above embodiment, only one stage of the inner corrugated pipe is provided. However, as shown in FIG. 12, depending on the situation, the corrugated sheet is connected in the circumferential direction and the vertical direction to form a plurality of stages (in the illustrated example). In this case, a two-stage inner corrugated pipe 20 ′ may be used. If the inner corrugated pipe is raised and submerged concrete is poured to that height, the water pressure resistance of the outer corrugated pipe increases. Therefore, if necessary, depending on the diameter of the outer corrugated pipe and the water depth H, the inner corrugated pipe shown in the figure is used. The height h is increased as in 20 '. That is, (Hh) is prevented from exceeding a certain value.

It should be noted that the present invention is also applicable to a deadline construction method for simply creating a work space underwater, such as when there is no existing pier or the like, that is, when a new pier is constructed.
Naturally applicable. In addition, it can be applied to a mere bottom without a foundation.

[0023]

According to the deadline method of the present invention, a corrugated pipe is sequentially assembled on a scaffold of a barge or the like to form a partial double cylindrical structure comprising an outer corrugated pipe, an inner corrugated pipe, and a connecting member. Partially double tubular structure on the bottom of the water
The underwater concrete is placed between the outer corrugated pipe and the inner corrugated pipe, so there is no need for the high head space required when driving steel sheet pile. Therefore, it is suitable for the case of reinforcing existing underwater legs. It is also suitable when the rock is hard or there is a problem of noise.

According to the method of the present invention, the outer corrugated pipe and the inner corrugated pipe are assembled, the two are integrally connected by a connecting member, and underwater concrete is poured between the outer corrugated pipe and the inner corrugated pipe. Are easy and the workability is very good.

Further, in the method of the present invention, since the corrugated pipe (that is, the inner corrugated pipe) provided for placing underwater concrete is inside the main body portion (that is, the outer corrugated pipe) of the deadline structure, even if the foundation is narrow, It can be easily installed on this narrow foundation. Also, since underwater concrete is poured inside the main body part higher than the water surface, it is relatively easy to prevent underwater concrete from flowing out.

In the deadline method of the present invention,
The outer corrugated pipe can be removed very easily, except for the concrete placement. Therefore, most of the corrugated sheet can be reused and is economical.

[Brief description of the drawings]

FIG. 1 is a view for explaining a deadline method according to one embodiment of the present invention and is a diagram showing an initial stage.

FIG. 2 is a view showing a stage following the one in FIG. 1 in the deadline method of the embodiment.

FIG. 3 is a diagram showing a stage following FIG. 2 in the deadline method of the embodiment.

FIG. 4 is a view showing a stage following the one in FIG. 3 in the closing method according to the embodiment.

FIG. 5 is a view showing a stage following the one in FIG. 4 in the deadline method of the embodiment, in which the installation of the deadline structure is completed.

FIG. 6 is a view for explaining a procedure for assembling a corrugated pipe in the deadline method.

FIG. 7 is a sectional view taken along the line AA of FIG. 3;

FIG. 8 is an enlarged view of a connecting member in FIG. 3 and the like.

FIG. 9 is an explanatory diagram of an example of a buoyancy prevention measure and an underwater concrete outflow prevention measure in the deadline method of the embodiment.

FIG. 10 is a sectional view of a main part showing an embodiment in the case where the upper surface of the foundation is inclined.

FIG. 11 is a sectional view of an essential part showing an embodiment in the case where sandbags are used for preventing outflow of underwater concrete.

FIG. 12 is a view corresponding to FIG. 5, showing an embodiment in which an inner corrugated pipe having a plurality of stages is used.

FIG. 13 is a view for explaining a conventional closing method.

[Explanation of symbols]

Reference Signs List 11 bridge pier (underwater leg) 12 bridge girder 13 foundation 15 barge 16 wire 17, 19 corrugated sheet 18 outer corrugated pipe 18a, 18b, 18c, 18d, 19e, 18f 1
Step corrugated pipe 20 Inner corrugated pipe 21 Connecting member 22 Partial double tubular structure (steel structure) 24 Underwater concrete 31 Anchor or reinforcing bar 32 Reinforcing bar 33 Sealing material 34 Sandbag

Claims (3)

[Claims] 1. A step of connecting a plurality of arc-shaped corrugated sheets in a horizontal circumferential direction and a vertical direction to form an outer corrugated pipe having a plurality of stages, and a circle having a smaller curvature than the corrugated sheet of the outer corrugated pipe. A plurality of arcuate corrugated sheets are connected circumferentially or circumferentially and vertically so as to face at least the inner surface of the lowermost portion of the outer corrugated pipe, so that the corrugated sheet is shorter than one corrugated pipe or the outer corrugated pipe. Forming a plurality of stages of inner corrugated pipes, and connecting the inner corrugated pipes and the outer corrugated pipes with connecting members to form a partially double tubular structure;
Lowering the partial double-cylinder structure and placing it on the bottom of the water; then, casting underwater concrete between the outer corrugated pipe and the inner corrugated pipe of the partial double-cylinder structure; A process of draining water inside the outer corrugated pipe after hardening. 2. A deadline method applied to an existing underwater leg reinforcing work for reinforcing an existing underwater leg, comprising connecting a plurality of arcuate corrugated sheets in a circumferential direction so as to surround the underwater leg. Assembling the one-stage corrugated pipe, raising the one-stage corrugated pipe by almost one stage height, and assembling the subsequent lower-stage corrugated pipe in the same manner and connecting it to the preceding corrugated pipe, A step of forming an outer corrugated pipe having a plurality of steps; and forming a plurality of arcuate corrugated sheets having a smaller curvature than the corrugated sheet of the outer corrugated pipe so as to face at least the inner surface of the lowermost step of the outer corrugated pipe. Circumferentially or circumferentially and vertically connected, one stage or multiple sections shorter than the outer corrugated pipe A step of forming an inner corrugated pipe of several stages and connecting the inner corrugated pipe and the outer corrugated pipe by a connecting member to form a partially double tubular structure; Lowering the body and placing it on the foundation of the underwater legs, then casting underwater concrete between the outer corrugated pipe and the inner corrugated pipe of the partial double tubular structure; A process of draining water in the outer corrugated pipe. 3. A steel structure used in the closing method according to claim 1 or 2, wherein a plurality of arcuate corrugated sheets are connected in a horizontal circumferential direction and a vertical direction. And a plurality of arcuate corrugated sheets having a smaller curvature than the corrugated sheet of the outer corrugated pipe are circumferentially or circumferentially opposed to at least the inner surface of the lowermost portion of the outer corrugated pipe. And one or more inner corrugated pipes shorter than the outer corrugated pipe connected to the outer corrugated pipe via a connecting member. Steel structure for the deadline method.