JPS63251546A - Method for building concrete structure - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for constructing a concrete structure, in which a foundation form is installed, then concrete is poured and allowed to harden over a predetermined period of time.

[Conventional technology]

In the construction of general concrete structures, plywood is used to form the building frame using concrete, which is a mixture of gravel, sand, cement, and water.

Alternatively, a construction method has been adopted in which concrete is poured into a foundation formwork such as an iron plate, and after the concrete has solidified, the foundation formwork is removed (Japanese Patent Laid-Open Publication No. 75055/1983).

Next, we will explain the method for molding the electric panel installed in the central control room for operating and controlling the reactor of a nuclear couplant, and the foundation that will be installed on the floor of the central control room as a cable tray for the control panel.

As shown in FIG. 7, the floor of the middle massage room has a base 4 designed according to the shape and layout plan of the control panel 1°.

A groove 2° is provided between the bases 4 for passing the cable through. The depth of the groove is approximately 500 m/m, and as a method of forming the foundation while securing this groove, as described above, the foundation form 19 is assembled from a combination of plywood etc. commonly used in construction, and the foundation 4 is assembled. A method of molding is used. In the same figure, 7 is the floor slab, 2.9 is the reinforcement, and 3 is the deck plate.

7 is a cable, 8 is a strut, 11 is a floorboard, 12 is a plywood,
13 indicates a support plate. That is, the plywood 12 and the support plate 13
A foundation formwork 19 is formed.

[Problem that the invention seeks to solve]

However, with conventional construction methods, the work of removing the foundation formwork remains after the concrete has cured. This removal work requires manpower, and in the case of large structures such as nuclear reactor plants, it takes more than several days with 8 hours of work per day. ．．
In order to receive 9 kV power, building construction, equipment settings,
Since the electrical system start-up and the operation process for the central control room constitute critical processes, it was necessary to assemble the most efficient work process in order to shorten the process. Here, a critical process means that another process cannot be started until one process is completed.

Therefore, work such as removing the foundation formwork after concrete hardens, which occurs in this area, not only delays the start of equipment installation, but also causes confusion between construction and mechanical work after the start of mechanical work, resulting in reduced on-site man-hours. was the cause of the increase.

The purpose of the present invention is to reduce manpower and construction period,
Another object of the present invention is to provide a method of constructing a concrete structure, such as a nuclear reactor building, in which construction work and machine installation work are not complicated after concrete assimilation.

[Means for solving problems]

The present invention is a method for constructing a concrete structure in which a foundation form is installed, concrete is poured, and then solidified after a predetermined period of time, in which ice blocks are used in the foundation form.

[Effect]

The foundation formwork is made from ice blocks, and after the concrete hardens, the ice blocks are melted and released as water, eliminating the need to remove the foundation formwork. In addition, although removal work by one person is limited to 8 hours a day, ice can be melted 24 hours a day, making it possible to melt ice earlier, thereby shortening the construction period. It is something.

〔Example〕

Hereinafter, embodiments of the present invention will be explained with reference to FIGS. 1 to 3. Six embodiments are for constructing the floor of the central control room of a nuclear reactor plant, and the ice block of the present invention has a concrete structure. Can be used for all things.

FIG. 2 is a plan view of the floor of the central control room, FIG. 3 is a sectional view thereof, and FIG. 1 is an enlarged sectional view of the main part of the concrete structure. The floor of the middle massage room is made up of a base 4 for setting electrical panels and control panels, and a tray for cables 7 that communicate between each control panel 10.

The procedure for placing the floor slab 1 for the middle rolling room floor is that after completing the construction of the support beam 14 for setting the deck plate 3 provided on the bottom surface of the slab, the deck plate 3 is laid, and the main reinforcement of the floor slab 1 is placed on top of it. Install reinforcement 3.

After that, concrete is poured and floor slab 1 is finished.

Next, the main reinforcing bars 8 of the foundation 4 are attached, and the reinforcing bars 9 are set using the inserts 8 as a base. The distance between the foundation pedestal 4 and the adjacent foundation pedestal 4 is approximately 500 to 600 m/m, and the height of the foundation pedestal 4 is also approximately 500 m/m.

Ice blocks 5 are installed between each foundation 4 as a formwork for the foundation. From the viewpoint of work efficiency, it is desirable that the block formwork for manufacturing the ice blocks 5 be installed around the working area of the floor slab 1 or outdoors. Regarding the production of ice block 5.

Water is poured into this block formwork, and a cooling medium such as liquid nitrogen is poured into the small diameter heat medium flow pipe 6 for transporting the heat medium set in this block formwork. As a result, the flow pipes 6 are cooled, the water in the block mold is frozen, and the ice block 5 having the heat medium flow pipes 6 is manufactured.

Here, the heat medium flow pipes 6 are formed so as to be connectable to each other.

The ice blocks 5 are lifted up by a crane and sequentially installed at predetermined positions on the floor slab 1 to connect each flow pipe 6. 1st
Similar ice blocks 5 are also installed in the longitudinal direction shown in the figure (direction perpendicular to the plane of the paper).

After installation, if a cooling medium such as liquid nitrogen is flowed into the heat medium flow pipe 6 of the ice block 5, the ice block 5 will naturally melt even if the ice block is installed in an environment with the melting temperature of ice. This can prevent it from flowing away.

Next, concrete is placed in the space between the ice blocks 5 that will become the foundation 4. Due to this.

The molding of the base 4 is completed. The concrete surface is finished using levers and the required curing period is completed. When the concrete hardens and the ice block 5 becomes unnecessary, the supply of cooling medium to the heat medium flow pipe 6 is stopped to naturally melt the ice. Or, run a heating medium through it to melt it in a shorter period of time. Melted water will be disposed of through nearby temporary drainage piping. In addition,
When the ice block 5 is used in an environment where ice does not melt, such as in Hokkaido during the winter, there is no need to flow the cooling medium through the heat transfer pipe 6 until the poured concrete has solidified, and the concrete assimilation Afterwards, a heating medium such as heated water is flowed into the flow path pipe 6.

In this way, even when the structural work on the construction side is completed and the panel installation work on the machinery side begins, there is no need to remove the concrete foundation formwork, so construction and machinery work can be done in the same area. At the same time, it becomes possible to alleviate the critical path of the construction process for the entire plant.

Moreover, without providing the heat medium flow pipe 6 in the ice block 5,
It is also possible to maintain the shape of the ice blocks 5 and secure the curing period of the concrete foundation 4 by controlling the atmospheric temperature of the central operation room at around 0° C., where the ice does not melt. In the above, the case where the shape of the ice block 5 is a rectangular prism has been explained, but for example, it is possible to manufacture an ice block having a shape that is a combination of the ice block 5 and the floor material 11 shown in FIG. If this is done, the floorboard 11 will be flush with the foundation 4 after construction.

4 to 6 show other embodiments of the present invention, in which the present invention is applied to a formwork for the foundation of a through hole in the biological shielding wall 16 through which the penetration 18 of the reactor containment vessel 17 is penetrated. This is what I did. In this case, since the biological shielding wall 16 must be constructed with the penetration 18 already fixed, the ice block 5 should not have a simple shape as described above, but be composed of a cylindrical curved surface. become. Therefore, in advance, the covering cover 1 is made into the shape shown in the figure by pouring fluid into it.
5 is prepared, a heat medium flow pipe 6 is arranged therein,
A cooling medium flows through it. As a result, a cylindrical ice block 5 shown in the figure is completed. By fitting and installing this ice block 5 over the penetration 18 before placing concrete for the biological shielding wall 16, it becomes possible to provide a through hole for the penetration 18 in the biological shielding wall 16.

After the concrete hardens, the ice is melted and washed away as water, and the covering cover 15 and the heat medium flow pipe 6 are removed in the same manner as described above. If the cover 15 is removed in advance, only the heat medium flow pipe 6 will remain after the ice melts.

〔Effect of the invention〕

According to the present invention, since ice blocks are used as the foundation formwork, it is possible to reduce the number of labor involved in removing the formwork after concrete assimilation, and furthermore, the ice can be melted by using it 24 hours a day. Save time by
Overall, the construction period of the concrete structure can be shortened.

In addition, in the case of structures such as nuclear reactor buildings, construction/4! Not only will the complexity of mechanical work be improved, but it will also be possible to reduce the number of man-hours required to construct the central control room, which forms a critical path in the plant construction process.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a foundation showing an application example of the ice block construction method of the present invention, and FIG. 2 is a plan view of the floor of the middle massage room. 3 is a sectional view taken along the line m-m in FIG. FIG. 7 is a cross-sectional view showing an example of the formwork structure of the conventional construction method for the floor of the middle kneading room. 4... Foundation stand, 5... Ice block, 6... Heat medium flow pipe, 7... Cable, 10... Electricity/control panel, 15... Sheathing cover, 16... ...Biological shielding wall, 17
... Reactor containment vessel, 18... Henetration.

Claims (1)

[Claims] 1. After installing the foundation formwork, pouring concrete;
A method for constructing a concrete structure in which the concrete structure is solidified over a predetermined period of time, the method comprising using ice blocks as a foundation formwork. 2. A method of constructing a concrete structure according to claim 1, wherein the ice block is provided with a heat medium flow pipe. 3. A method of constructing a concrete structure according to claim 1, wherein the concrete structure is a floor of a central control room of a nuclear reactor plant. 4. The method of constructing a concrete structure according to claim 1, wherein the concrete structure is a biological shielding wall that allows penetration of a nuclear reactor containment vessel. 5. A method for constructing a concrete structure according to claim 1 or 3, wherein after concrete is poured, the indoor temperature is lowered to a temperature that prevents ice blocks from melting and maintained until the concrete solidifies. 6. A method for constructing a concrete structure according to claim 2, in which a cooling medium is poured into a heat medium flow pipe of an ice block installed in an environment at an ice melting temperature until the concrete cast is solidified. 7. A method for constructing a concrete structure according to claim 2, in which a heating medium is poured after the concrete cast in the heating medium flow path of an ice block installed in an environment with a non-melting temperature of ice has solidified. .