JPH09256379A - Manufacturing of steel shell caisson - Google Patents

Abstract

PROBLEM TO BE SOLVED: To carry out execution of a steel caisson main body part as a main body of the steel shell caisson and execution of a bottom slab concrete placed therein in separate places respectively to effectively use the existing equipments to promote manufacturing efficiency of the steel shell caisson and to carry out execution without giving any influence to the strength thereof. SOLUTION: A steel caisson main body 1 having an open top with a hollow inside is manufactured, and as the first stage of work, when a bottom slab concrete is placed on the inside thereof, the steel caisson main body 1 is manufactured in such a place having launching equipments such as dry dock, etc. Then, as the second stage of work, the caisson main body 1 manufactured in the first stage of work is launched and is floated, and the caisson main body 1 is towed and is moored to a quay 30 for placing the bottom slab concrete. As the third stage of work, a plurality of concrete pump cars A1 are arranged on the quay 30, and the bottom slab concrete is placed to the inside of the caisson main body 1 by means of the concrete pump cars A1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for manufacturing a steel shell caisson, and more particularly to a technique for placing bottom slab concrete in a huge steel shell caisson used for construction of artificial islands.

[0002]

2. Description of the Related Art For example, in the construction of a huge marine structure such as an artificial island, a giant steel shell caisson may be used in place of a general concrete caisson used for construction of a quay or a seawall. . This steel shell caisson itself,
It is usually formed in the shape of a hollow box with an open upper surface, but bottom slab concrete may be placed inside the box if necessary.

In order to drive this bottom slab concrete, it is preferable to use a manufacturing place rather than a steel shell caisson digging site. This is because, for example, when the steel shell caisson is towed or submerged, the steel shell caisson is less susceptible to the influence of the wind, which is very effective in deepening the draft of the steel shell caisson. Furthermore, it is an important structural element for the purpose of reinforcing the bottom portion of the steel shell caisson after sunk, reinforcing the joint portion between the bottom portion and the foundation pile head, and improving the pile head joint work. is there. Of course, such bottom slab concrete can also be constructed at the site of sunk.
However, this is a work of placing concrete that is inseparable in water, which is not preferable in terms of workability and construction cost.

By the way, when manufacturing such a huge steel shell caisson, it is generally known as shipbuilding equipment,
I often use a dry dock nearby. This is because it is possible to easily launch a large and heavy steel shell caisson, and it is also very convenient to transport it by sea to its sunk position.

[0005]

However, when the dry dock is used for manufacturing the steel shell caisson as described above, there are problems to be solved in the following points.

That is, considering the time and place for placing the bottom slab concrete in the steel shell caisson, first, at that time, it is necessary to place the steel shell caisson before it is sunk. Therefore, a method of placing it in the dry dock in advance can be considered, but this has many problems.

First, in addition to the fact that the shipyard is not equipped with large-scale concrete pouring equipment, it is not possible to effectively use the existing concrete pump truck etc. in the deep and vast dry dock. is there.

Secondly, as for the period required for placing the bottom slab concrete and curing it, it is impossible to manufacture the next steel shell caisson and it is impossible to effectively utilize the equipment.

Thirdly, the bottom slab concrete has a considerable weight due to the pouring lift reaching about 5 m, and therefore, among the structural elements of the steel shell caisson originally designed as a structure to be laid, The strength of the caisson body made of steel and the weight of the dry dock itself cannot be ignored.

Fourth, as a solution to the third problem, a method of placing bottom slab concrete with the steel shell caisson itself floating in the dock can be considered. There is a problem of water depth, which is still not an appropriate method.

The present invention has been made in consideration of the above points. The construction of a steel caisson main body, which is the main constituent of a steel shell caisson, and the construction of bottom slab concrete to be placed inside thereof. Providing technology that enables existing facilities to be effectively used to improve manufacturing and production by performing them in different locations, and in which construction can be carried out without affecting the strength due to its own weight. The purpose is to do.

[0012]

In order to solve the above-mentioned problems, according to the present invention, when a caisson main body made of steel having an open upper surface and made of hollow steel is manufactured and bottom slab concrete is placed therein, the following A , B and C are performed. A First step of manufacturing the above-mentioned steel caisson body at a place having a launch facility such as a dry dock. B The second step in which the caisson body manufactured in the first step is launched and floated, and the caisson body is towed and moored to the quay for placing bottom slab concrete. C The third step of placing multiple concrete pump cars on the quay and using the concrete pump cars to place bottom slab concrete in the caisson body. Here, when placing the bottom slab concrete, the area for placing the bottom slab concrete by each concrete pump truck is defined in advance, and the center of gravity of the caisson body is controlled by controlling the amount of concrete placed by each concrete pump truck. It is also possible to control the position. Further, in the third step, it is possible to control the quantity of concrete to be placed by each concrete pump car based on the measured value of the center of gravity of the caisson body. In addition, a high-pressure hose for concrete pressure feed extending from the boom tip of the concrete pump car is positioned at the top end of the caisson body, and a concrete pressure feed pipe extending from the high-pressure hose toward the placement area of the bottom slab concrete is arranged in the caisson body. By doing so, the caisson body can be set so as to be able to cope with the displacement of the self-sinking caused by the pouring of concrete.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will be described below with reference to the accompanying FIGS.

FIG. 1 is a perspective view showing a manner of placing bottom slab concrete on a caisson body of a steel shell caisson according to the present invention, FIG. 2 is a schematic plan view thereof, FIG. 3 is a schematic vertical sectional view thereof, and FIG. [Fig. 3] is a construction flow diagram for placing bottom slab concrete.

As can be understood from these figures, the caisson body 1 constitutes the main body of a so-called steel shell caisson in which a large number of large and small H steels are used for the skeleton and steel plates are used for the side plates. Formed into a shape. This caisson body 1
Has an upper surface opened, and the inside thereof is divided into three chambers by two partition walls 2 which are parallel to each other. The lower part of the partition wall 2 is not provided in a portion where a slab concrete to be described later is poured. That is, the partition 2 has a structure rising from the bottom slab concrete. The size of the caisson body 1 may be several tens of meters or more in length, width, and height.

When the caisson body 1 having such a structure and size is manufactured, it is manufactured, for example, using a dry dock of a shipyard. Before launching the caisson body 1, as shown in the construction flow diagram of FIG. 4, pile head formwork assembly, bottom slab concrete placement scaffolding assembly, concrete placement piping installation, placement equipment and lighting equipment. Perform construction such as placement in advance.

On the other hand, on the pier side, the assembling of the fluidizing agent injection scaffold for concrete, the quay curing, the lighting, before the mooring and mooring of the caisson body 1 are carried out.
Preparations for placing bottom slab concrete will be made by carrying out various operations such as installation of safety equipment and placement of concrete pump trucks.

After such preparation, the caisson body 1
The bottom slab concrete C is placed therein, and the structure and function of the bottom slab concrete C will be described more concretely with reference to the sectional view of FIG.
That is, the caisson main body 1 is towed to a target setting place after the bottom slab concrete C is set, and is set there. At the time of this sinking, the template 4 is supported by the head portions of a large number of foundation piles 3 that have been constructed in advance, and the caisson body 1 is installed and fixed on the template 4. The template 4 is fixed to the foundation pile 3, and the head of each foundation pile 3 penetrates the template 4 and faces the caisson body 1.

Therefore, in the portion of the bottom slab concrete C, a large number of voids 5 for drawing in the heads of the respective foundation piles 3 are formed. These cavities 5 are formed by assembling the formwork (not shown) necessary for forming the cavities 5 before placing the bottom slab concrete C. Also,
A watertight temporary lid f is detachably attached to a hole on the bottom surface side of the caisson body 1 provided for guiding the head of the foundation pile 3 into the void 5. In FIG. 5, reference numeral 6 is a portion for placing pile head connection concrete, 7 is a gasket, and 8 is a gasket.
a and 8b are side walls, and 9 is an upper floor beam.

FIG. 6 is a side view of the concrete pouring scaffold 10, which uses an internal member (for example, the first step of a beam) of the caisson body 1 as a supporting member and assembles it as a hanging scaffold by a single pipe 11. It is a thing. That is, the single pipe 11 is used to bridge the bottom beam 12 of the caisson body 1 and fixed by a clamp or the like to fix the scaffolding plate 1
3 is laid. The height of the scaffolding plate 13 is about 1 m above the top of the bottom slab concrete C to be cast. Here, K is a pile head formwork and 14 is a sleeve pipe.

Concrete pouring scaffold 10 having such a structure
Are vertically and horizontally arranged near the bottom of the caisson body 1, as shown in FIG. This arrangement relationship is performed here based on the rational division of the area where the bottom slab concrete C should be placed, as shown in FIG. That is, the casting area of the bottom slab concrete C is divided into 6 equal parts on the left and right sides and 2 equal parts on the front and rear sides, for a total of 12 equal parts, as indicated by the broken line in the figure. Therefore, the placement scaffolding 10 is arranged so that the position viewed from above is exactly in the center of each section. In addition, the setting scaffolding 10 for communication
About a, it is arranged near the boundary of the section. As a result, the concrete pouring scaffold 10 has a planar lattice shape as a whole.

Regarding the concrete pouring pipe 20, a receiving stand 21 is attached to the uppermost stage of the internal member of the caisson body 1, vertical pipes 22 are vertically piped up to the concrete pouring scaffold 10, and from there, horizontal pipes 23 are used for the scaffolding plate 13.
The top is horizontally piped.

Now, when the manufacturing work of the caisson main body 1 in the dry dock is finished, it is launched and the casting quay 3
Tow to 0 (primary tow) and moored there. And
As shown in FIGS. 1 to 3, a plurality of concrete pump cars (A1 in the illustrated example) are provided at a position near the sea on the casting quay 30.
-A4, B1-B4, C1-C4) (12 units in total) are arranged in a horizontal row, and the concrete mixer truck 40 is arranged behind it. At least two concrete mixer trucks 40 are prepared for each concrete pump truck in order to ensure smooth supply of concrete.

In addition, each concrete pump car A1 to C4
The upper end of each boom 50 is lifted and bent into an arc shape as shown in FIG. 3, and a high-pressure hose 51 for concrete pumping extending from the end of the boom 50 is positioned at the top end portion of the caisson body 1. Then, it is connected to the vertical pipe 22 of the concrete pouring pipe 20, which is supported by the receiving stand 21. This work is performed for all concrete pump cars, and the preparation for placing the bottom slab concrete C is completed.

When the preparation for placing is completed in this way, the concrete is pumped from all of the concrete pump cars A1 to C4 all at once, and the work for placing the bottom slab concrete C is performed. At the time of this placing work, the center of gravity position of the caisson body 1 is controlled by controlling the placing amount of the divided placing regions, that is, by controlling the placing amount of concrete by the concrete pump truck. To

In this case, it is preferable that the concrete pouring quantity control by each concrete pump car is performed based on the measured value of the position of the center of gravity of the caisson body 1. As a measuring method, for example, a trim meter, an inclinometer, or the like equipped on a ship can be used. Furthermore, when performing with high accuracy, a caisson sinking management method using a three-dimensional automatic surveying system can be adopted.

In this method, for example, the three-dimensional coordinates of the caisson body 1 are optically measured, the attitude angles of the caisson body around the three axes are detected using a gyrocompass, an accelerometer, and the like, and the detected values are obtained. Based on this, for example, a computer performs arithmetic processing, and the result is controlled while being displayed on a display. By doing so, it is possible to perform the work of placing the bottom slab concrete C without tilting the caisson body 1.

It is very important to prevent the caisson body 1 from tilting. This is because, for example, when the caisson body 1 leans toward the quay side, the caisson body 1 strengthens the movement toward the quay side due to the influence of water pressure, wind, etc. On the contrary, when the caisson body 1 leans toward the opposite side, it moves away from the quay. This is because the caisson body 1 is instable in any case.

During the operation of placing the bottom slab concrete C, since the boom 50 is arched, it is possible to allow the caisson body 1 to move up and down by adjusting the height of the tip of the boom 50. It will be ready. Therefore, it is possible to cope with the change in the self-sink of the caisson body 1 due to the pouring of concrete by the concrete pump car. Furthermore, it is possible to cope with the vertical movement of the caisson body 1 due to the ebb and flow of the tide.

After the work of placing the bottom slab concrete C is completed and, if necessary, a curing period is passed, the caisson body 1 is secondarily towed to a desired settling place.

9 and 10 show a plan view and a rear view of the concrete fluidizing agent charging facility 60.
For the concrete to be placed, ready-mixed concrete was transported to the site, lightened and added, and fluidized by stirring the transport vehicle. In the case of fluidization at the site, fluidization was carried out as close as possible to the concrete driving place, and in order to enable immediate driving, the fluidizing agent charging equipment as shown in the figure was installed. As for the weight of the fluidizing agent, a pump type automatic weighing device (a combination of the pump 61 and the timer board 62) was used, and the weighing accuracy was verified and adjusted in advance.

This fluidizing agent charging equipment 60 has a horizontal 4
The truck mixer trucks 40 are divided into two sections and are configured so that four truck mixer trucks 40 can enter at the same time and receive the supply of the fluidizing agent. 9 and 10, 63 is a fluidizer storage tank, 64 is a generator, 65 is a steel scaffolding plate, 66 is an eye lamp, 67 is a bite frame, and 68 is stairs.

[0033]

As described above, according to the present invention, when manufacturing an internal hollow steel caisson main body with an open upper surface and placing bottom slab concrete inside the caisson main body, the steel caisson main body is The first step of manufacturing at a place with a launch facility such as a dry dock, and the caisson body manufactured in the first step is launched and floated, and the caisson body is towed to pour bottom slab concrete Since the second step of mooring the pier and the third step of placing a plurality of concrete pump cars on the quay and using each of these concrete pump cars to place bottom slab concrete in the caisson body, The existing equipment can be installed by performing the construction of the steel caisson main body, which is the main component of the steel shell caisson, and the construction of the bottom slab concrete that is placed inside the caisson body at different locations. It is possible to improve the productivity of using, moreover, it may be applied without strength influence by its own weight. Also, by pouring the bottom slab concrete before towing the caisson body to the place where it was sunk, the draft of the caisson body can be made deep and constant, thereby avoiding problems such as the subsequent structural strength. Various operations can be performed smoothly.

Further, when the bottom slab concrete is poured, the areas for placing the bottom slab concrete by the concrete pump cars are defined in advance, and the quantity of concrete poured by the respective concrete pump cars is controlled to control the caisson body. It is possible to control the position of the center of gravity of the. As a result, the caisson body can be installed safely without being biased in the center of gravity.

Further, in the third step, the quantity of concrete placed by each concrete pump car is controlled based on the measured value of the center of gravity of the caisson body, so that it can be managed more safely and accurately. It is possible to perform concrete pouring work.

Further, a high-pressure hose for pumping concrete, which extends from the boom tip of the concrete pump car, is positioned at the top end of the caisson body, and concrete pumping that extends from the high-pressure hose toward the placing area of the bottom slab concrete is placed inside the caisson body. By arranging the pipes, the caisson body can be set to cope with the self-sinking displacement of the caisson body caused by the pouring of concrete. Therefore, the operation of placing concrete from the quay side to the floating caisson body can be easily performed without any trouble.

[Brief description of drawings]

FIG. 1 is a perspective view showing a procedure for placing bottom slab concrete on a caisson body.

FIG. 2 is a schematic plan view of FIG.

FIG. 3 is a schematic vertical sectional view of FIG.

[Fig. 4] Fig. 4 is a construction flow diagram for placing bottom slab concrete.

FIG. 5 is a cross-sectional view showing a state in which a caisson body is installed on a foundation pile.

FIG. 6 is a partial side view of a concrete pouring scaffold.

FIG. 7 is a plan view showing an arrangement of concrete pouring scaffolds.

[Fig. 8] Fig. 8 is a plan view showing a placement section division of bottom slab concrete.

FIG. 9 is a plan view of a concrete fluidizing agent charging facility.

FIG. 10 is a rear view of a concrete fluidizing agent charging facility.

[Explanation of symbols]

 1 caisson main body 2 partition wall 3 foundation pile 4 template 5 void space 6 pile head connection concrete 7 gasket 8a, 8b side wall f temporary lid 10 concrete placing scaffolding 10a connecting placing scaffolding 11 single pipe pipe 12 cutting beam 13 scaffolding plate 14 Sleeve pipe K Pile head formwork A1 to C4 Concrete pump car 20 Concrete placing pipe 21 Receiving stand 30 Quay 40 Concrete mixer truck 50 Boom 51 High pressure hose 60 Fluidizer injection equipment

Claims (4)

[Claims] 1. A steel which is characterized by performing the following steps A, B and C when a caisson body made of steel having an open upper surface is made and a bottom slab concrete is placed therein. Manufacturing method of shell caisson. A First step of manufacturing the above-mentioned steel caisson body at a place having a launch facility such as a dry dock. B A second step in which the caisson body manufactured in the first step is launched and floated, and the caisson body is towed and moored to the quay wall for placing the bottom slab concrete. C A third step of arranging a plurality of concrete pump cars on the quay and using the respective concrete pump cars to pour bottom slab concrete into the caisson body. 2. A caisson is prepared by preliminarily demarcating an area for placing concrete slabs by each concrete pump car when placing the slab concrete, and managing the quantity of concrete laid by each concrete pump car. The method for manufacturing a steel shell caisson according to claim 1, wherein the position of the center of gravity of the main body is controlled. 3. The method according to claim 1, wherein in the third step, the quantity of concrete placed by each concrete pump car is controlled based on the measured value of the center of gravity of the caisson body. Steel shell caisson manufacturing method. 4. A concrete high-pressure hose extending from the boom end of the concrete pump car for concrete pumping is positioned at the top end of the caisson main body, and concrete extending from the high-pressure hose toward the casting area of the bottom slab concrete is placed inside the caisson main body. The method for producing a steel shell caisson according to any one of claims 1 to 3, characterized in that the pressure feeding pipe is arranged so as to be capable of coping with the displacement of the self-sinking of the caisson body due to the placing of concrete. .