JPH0247588A - Pedestal made of steel - Google Patents

Abstract

PURPOSE:To easily install a pedestal made of steel by providing concrete filling tubing in the inside of a cylinder in the long size pedestal made of steel in which a plurality of short size cylinders are stacked. CONSTITUTION:A cylindrical structure 2 made of steel consists of an inner cylinder 3 which constitutes the inside of a reactor pressure vessel pedestal 1 made of steel and an outer cylinder 4 surrounding the inner cylinder at regular intervals. Reinforcing materials 5 for reinforcing the cylinders 2a-2f made of steel are mounted between the outer cylinder 4 and the inner cylinder 3. Further, after the cylinders 2a-2f are installed, concrete filling tubing 6 for filling the inside thereof with concrete is formed by utilizing a part of the reinforcing materials 5. The reactor pressure vessel pedestal 1 made of steel is installed so that short size cylinders 2a-2f of the cylindrical structure 2 are divided to produce at a factory and they are assembled by welding and the like at a site to fill the inside of the cylinders 2a-2f with concrete from the concrete filling tubing 6.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a steel pedestal, and in particular to a steel pedestal for a nuclear reactor pressure vessel that shortens the installation process and improves industrial safety. Regarding the pedestal.

(Prior Art) FIG. 3 shows a boiling water nuclear reactor, and in the figure, reference numeral 21 indicates a reactor containment vessel housed in a reactor building 22. The inside of this reactor containment vessel 21 is divided into two by a diaphragm floor 8 into a dry well 23 and a wet well 24. A reactor pressure vessel pedestal 26 whose upper portion is disposed within the dry well 23 is erected on a basic concrete mat 25 constituting the bottom surface of the wet well 24 . A reactor pressure vessel 27 mounted and supported on the reactor pressure vessel pedestal 26 is housed in the dry well 23, and the reactor pressure vessel 27 is surrounded by a reactor shielding wall 28. In addition, the diaphragm floor 8 has a large number of vent pipes 1 toward the wet well 24.
0 is planted.

In a boiling water reactor configured in this way, the reactor pressure vessel pedestal 26 supports heavy objects such as the reactor pressure vessel 27, so it is made of reinforced concrete with a very large amount of reinforcing steel, and all installation is done on-site. It was getting worse.

However, the completion of this reactor pressure vessel pedestal 26 is a necessary condition for installing the diaphragm floor 8, and the installation of the diaphragm floor 8 is also a necessary condition for the on-site installation of the upper part of the reactor containment vessel 21. .

Further, after the reactor pressure vessel pedestal 26 is completed, the reactor shielding wall 28 is installed, the reactor pressure vessel 27 is installed, and structures inside the reactor containment vessel 21, piping, etc. are installed. Therefore, shortening the installation process of the reactor pressure vessel pedestal 26 is an important factor in shortening the nuclear power plant construction process. Therefore, in order to shorten the installation process of the reactor pressure vessel pedestal 26, the main structure of the reactor pressure vessel pedestal 26 is made of steel and concrete, eliminating the reinforcing steel assembly work that was conventionally done on site, and The fabricated part is manufactured in parts at a factory, assembled on site by welding or bolting, the inside of the steel part is filled with concrete, and the reactor pressure vessel pedestal 26 is installed.

Next, a conventional concrete filling operation for a steel pedestal of a nuclear reactor pressure vessel will be explained with reference to FIG. Fourth
The figure is a half-sectional view showing a steel pedestal of a nuclear reactor pressure vessel. First, once the installation of the reactor pressure vessel steel pedestal foundation 7 is completed, the short steel cylindrical bodies 2a to 2d, which are manufactured in parts at the factory, are mounted up to the number of stages on which the diaphragm floor 8 is installed, and then welded or bolted together. assembled and integrated. Next, a column support 9 that supports the diaphragm floor 8 from below is installed, and the diaphragm floor 8 is mounted on the cylindrical body 2d and the column support 9. Next, the short cylindrical bodies 2e, 2 on the top of the reactor pressure vessel steel pedestal 1
f and is assembled by welding or bolting. On the other hand, on the diaphragm floor 8, the insertion and planting work of the vent pipe 10 and the installation work of the pipe whip structure 11 are carried out in parallel after the vent pipe is inserted.

Once the assembly of the steel cylindrical structure 2 of the reactor pressure vessel steel pedestal 1 has been completed, the steel cylindrical structure 2
In order to fill the reactor pressure vessel with concrete, a temporary concrete filling pipe 12 is connected to the reactor pressure vessel steel pedestal 1.
It is laid inside and outside of the steel cylindrical structure 2. Next, concrete is filled from the lower stage of the steel cylindrical body 2a, and filling work is performed by replacing the temporary concrete filling pipe 12 every predetermined number of filling stages. When this filling work is completed, the temporary concrete filling pipe 12 is temporarily removed. Once the removal of this temporary concrete filling pipe 12 is completed, the steel cylindrical structure (not shown) on the upper part of the reactor pressure vessel steel pedestal 1 is then mounted and welded or bolted to the reactor reactor. Pressure vessel steel pedestal 1
Assemble.

Subsequently, temporary concrete piping 12 was installed to fill the upper part of the reactor pressure vessel steel pedestal 1 with concrete.
is again suspended from the top of the steel cylindrical structure, and concrete filling work is carried out on the top of the steel pedestal 1 of the reactor pressure vessel. When the concrete filling work is completed, the temporary concrete filling pipe 12 is removed, the filling work of the reactor pressure vessel steel pedestal 1 is completed, and the installation of the reactor pressure vessel steel pedestal 1 is also completed.

(Problems to be Solved by the Invention) The concrete filling work as described above is mainly performed in the closed space constituted by the reactor pressure vessel steel pedestal 1. In other words, during the work of laying the temporary concrete filling piping 12 and filling with concrete, the work must be done inside the steel cylindrical structure 2, such as moving the temporary flexible piping for filling concrete into each space partitioned by steel plates. The filling operation took a considerable amount of time and was also undesirable from the standpoint of worker safety.

The present invention has been made to solve the above-mentioned problems, and aims to provide a steel pedestal that can shorten the construction period and improve the safety of workers.

[Structure of the Invention] (Means for Solving the Problems) The present invention provides a steel cylindrical structure made of a plurality of concentric short cylindrical bodies stacked together to make it elongated, and a reinforcement provided in the cylindrical structure. The present invention is characterized by comprising a reinforcing material and a concrete filling pipe attached to the reinforcing material or the inner surface of the cylindrical structure.

(Operation) Concrete filling inside the steel cylindrical structure is carried out using concrete filling piping that is previously attached to the inside of the structure. Therefore, unlike the conventional example, there is no need to install temporary concrete filling piping, and it can be used as a reinforcing member, and there is no need to remove the piping. Furthermore, by providing a concrete filling piping path for each short cylindrical body, there is no need for temporary flexible piping, and there is no need to move the temporary flexible piping inside the steel cylindrical structure.

Therefore, there is no need to install or remove temporary concrete filling piping, and there is no need for replacement work, so the construction period can be significantly shortened.

Furthermore, since there is no need to install temporary concrete filling pipes or move temporary flexible pipes inside the steel cylindrical structure, it is possible to improve the safety of workers.

(Example) An example of the present invention will be described with reference to FIGS. 1 and 2.

FIG. 1 is a half-sectional view showing an embodiment of a nuclear reactor pressure vessel steel pedestal according to the present invention. FIG. 2 is a bird's-eye view of the steel cylindrical structure in FIG. 1.

The same elements as those in the conventional example shown in FIG. 4 are given the same reference numerals.

This nuclear reactor pressure vessel steel pedestal 1 according to the present invention is composed of a steel cylindrical structure 2 made of elongated steel short cylindrical bodies 2a to 2f stacked together.

As shown in FIG. 2, the steel cylindrical structure 2 is composed of an inner cylinder 3 that forms the inside of the reactor pressure vessel steel pedestal 1, and an outer cylinder 4 that surrounds the inner cylinder 3 at regular intervals. . A reinforcing member 5 made of a steel plate is attached between the outer cylinder 4 and the inner cylinder 3 to reinforce the steel cylindrical bodies 2a to 2f.

Further, after the installation of the cylindrical bodies 2a to 2f, a concrete filling pipe 6 for filling the inside with concrete is installed.
It is made of a steel plate and is constructed using a part of the reinforcing material 5 as shown in FIG. To install the reactor pressure vessel steel pedestal 1, the short cylindrical bodies 2a to 2f of the steel cylindrical structure 2 are manufactured separately at a factory, and then assembled on site by welding or bolting. The inside is filled with concrete and the reactor pressure vessel steel pedestal 1 is installed.

Next, concrete filling work for the reactor pressure vessel steel pedestal 1 will be explained with reference to FIG. First, when the installation of the reactor pressure vessel steel pedestal foundation 7 is completed, the cylindrical bodies 2a to 2d, which are manufactured in parts at the factory, are mounted up to the number of stages on which the diaphragm floor 8 is installed, and assembled by welding or bolting. At this time, there is no need to weld or bolt the 6 parts of the concrete filling pipe. However, although there may be a gap of several millimeters, the upper and lower concrete filling pipes 6 are designed and manufactured so that they fit together. Next, a column support 9 that supports the diaphragm floor 8 from below is installed, and the diaphragm floor 8 is mounted on the reactor pressure vessel steel pedestal 1 and the column support 9.

Next, the steel cylindrical bodies 2e to 2f on the upper part of the reactor pressure vessel steel pedestal 1 are mounted and assembled by welding or bolting in the same manner as described above. On the other hand, on the diaphragm floor 8, the insertion and planting work of the vent pipe 10 and the installation work of the pipe whip structure 11 are carried out in parallel after the vent pipe is inserted. Once the assembly of the steel cylindrical structure 2 of the reactor pressure vessel steel pedestal 1 has been completed, in order to fill the steel cylindrical structure 2 with concrete, the temporary concrete filling piping 12 is made of steel. Cylindrical structure 2
It is connected to a concrete filling pipe 6 constructed using a part of the reinforcing material 5 inside. Next, concrete is filled from the lower part of the steel cylindrical structure 2 through this concrete filling pipe 6. When the steel cylindrical structure 2 is filled with concrete, the concrete filling pipe 6 is also filled with concrete. In order to fill each space surrounded by the inner cylinder 3, outer cylinder 4 and reinforcing material 5 of the steel cylindrical structure 2 with concrete, several concrete filling pipes 6 are installed inside the steel cylindrical structure 2. The temporary concrete piping 12 is connected to the concrete filling piping 6 in a predetermined order.
and fill the steel cylindrical structure 2 with concrete. When this filling work is completed, the portion of the temporary concrete filling pipe 12 up to the concrete filling pipe 6 is temporarily removed. This temporary concrete filling pipe 1
2 is completed, next the steel cylindrical structure 2 on the upper part of the reactor pressure vessel steel pedestal 1 is mounted, and the reactor steel pedestal 1 is assembled by welding or bolting. At this time, as in the case of the lower steel cylindrical structure 2,
There is no need to weld or bolt the six sections of concrete filling pipes to each other. However, although there may be a gap of several millimeters, there may be gaps between the upper and lower parts of the concrete filling pipe 6.
Design and manufacture to fit. Subsequently, in order to fill the upper part of the reactor pressure vessel steel pedestal 1 with concrete, the temporary concrete pipe 12 is connected to the concrete filling pipe 6, and the work of filling the upper part of the reactor pressure vessel steel pedestal 1 with concrete is carried out. When the concrete filling work of the space is completed, the concrete filling pipe 6 is also filled with concrete. Several concrete filling pipes 6 to fill each space with concrete.
is included in the steel cylindrical structure 1. Once the concrete filling work in each space and the concrete filling in the concrete filling pipe 6 are completed, the temporary concrete filling pipe 12
has been removed, the filling work for the reactor pressure vessel steel pedestal 1 has been completed, and the installation of the reactor pressure vessel steel pedestal 1 has also been completed.

According to the reactor pressure vessel steel pedestal 1 of this embodiment,
The concrete filling pipe 6 is built into the steel cylindrical structure 2 in advance at the factory, and the steel cylindrical structure 2 is installed at the site.
There is no need to install the temporary concrete filling pipe 12 inside. In addition, the concrete filling pipe 6 is constructed using the reinforcing material 5 of the steel cylindrical structure 2, and since the concrete filling pipe 6 is also filled with concrete, it is not necessary to use the conventional concrete filling pipe 6. There is no need to remove the filling piping. That is, the steel cylindrical structure 2
Since there is no need to install or remove the concrete filling pipe 12 inside the reactor pressure vessel, and the concrete filling work can be done inside the steel cylindrical structure 2, the installation work of the reactor pressure vessel steel pedestal 1 can be significantly shortened. can.

In addition, worker safety is expected to be improved by eliminating the need for concrete filling piping installation and removal work in the closed space that constitutes the reactor pressure vessel steel pedestal 1, that is, inside the steel cylindrical structure 2. It will be done. In addition, since the steel cylindrical structure 2 has a plurality of concrete filling pipes 6 so that each space partitioned by steel plates can be filled with concrete, concrete filling inside the steel cylindrical structure 2, which was conventionally carried out, is By eliminating the need to move temporary flexible piping, worker safety will be improved and man-hours on site will also be reduced.

In the above embodiment, the steel pedestal for a nuclear reactor pressure vessel has been described, but the present invention is not limited to this, and can be applied to the construction of other structures, bridge foundations, etc.

[Effects of the Invention] According to the present invention, since the concrete filling piping is installed in advance, the work of laying and removing the concrete filling piping in a closed space constituting a steel pedestal as in the conventional example is eliminated. This eliminates the need for steel pedestals, and the process for installing steel pedestals can be significantly shortened. In addition, by reducing the work required in the closed space that makes up the steel pedestal,
It has many effects such as improving worker safety and reducing man-hours.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of a steel pedestal for a nuclear reactor pressure vessel according to the present invention, FIG. 2 is a bird's-eye view of the steel cylindrical structure in FIG. 1, and FIG. FIG. 4 is a sectional view showing a water reactor, and FIG. 4 is a sectional view showing a conventional nuclear reactor pressure vessel steel pedestal. 1...Reactor pressure vessel steel pedestal 2
......Steel cylindrical structure 6...Pipe for concrete filling 12...
......Temporary concrete filling piping agent Patent attorney Nori Chika Ken Yudo Daishimaru Kenmura ``0 J D size 1

Claims (1)

[Claims] A steel cylindrical structure made of a plurality of concentric short cylindrical bodies stacked one on top of the other, a reinforcing material provided within the cylindrical structure, and a reinforcing material attached to the reinforcing material or the inner surface of the cylindrical structure. A steel pedestal characterized by being equipped with concrete filling piping.