JPH0625482B2 - Construction method of concrete wall in containment vessel - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for constructing a concrete wall in a reactor containment vessel.

“Prior Art and Its Problems” When the reactor containment vessel is made of concrete, as shown in FIG. 3, the liner plate 6 is integrally provided on the inner surface of the concrete side wall 11, and the dry well 16 and the suppression chamber are provided. It is designed to maintain the airtightness of 17.

Explaining an example of a conventional method for constructing the concrete side wall 11, a plurality of reinforcing cut-tees are arranged on the outer surface of the liner plate 6 so as to support the vertical weight of the liner plate 6, and the outer side of the liner plate 6 is also supported. A concrete formwork is provided on the inner surface of the liner plate 6, and the inner surface of the liner plate 6 is appropriately supported by a support material so that concrete can be poured. Therefore, as the concrete pouring process progresses, the supporting height of the support material for supporting the inner surface of the formwork and liner plate increases, the amount of work for installing and removing these supporting materials increases, and the concrete side wall construction process tends to become long. There was

On the other hand, as another conventional technique, there is a sliding foam method. This technique uses an inner mold and an outer mold having a height of about 1 to 2 meters, for example, to pour concrete almost continuously while lifting both molds with a jack. Since the formwork is installed so as to sandwich the concrete pouring cavity from above, the presence of the liner plate above the formwork is an obstacle, and it is necessary to stack the liner plates little by little as the formwork moves upward. there were. For this reason, the number of man-hours is long and the work period is long, which makes it difficult to adopt.

"Object of the Invention and Means for Achieving the Same" The present invention aims to effectively solve the problems of the prior art, shorten the construction process of the reactor containment vessel, and shorten the construction accuracy. In order to achieve the above, a step of arranging a plurality of reinforcing cut-outs in an upwardly extended state on the outer surface of the cylindrical liner plate at intervals in the circumferential direction to prevent vertical deformation of the liner plate, and A step of arranging an outer formwork for concrete pouring at an outer position of the liner plate and suspending a yoke frame supporting the outer formwork for cocrete placing on a reinforcing cutout; and the liner plate and outer side for concrete pouring The step of placing concrete in the concrete placing cavity formed between the formwork, and moving the yoke frame upward after the concrete placing step Then, there is a step of performing the next concrete pouring above the concrete pouring portion, and it is inevitable that the cut tee is installed on the liner plate of the concrete wall, and the concrete pouring is performed on the reinforcing cut tee. While the construction form is supported, the concrete is poured upwards almost continuously.

[Example] An example of a method for constructing a concrete wall in a reactor containment vessel according to the present invention will be described below with reference to the drawings.

1 and 2 show a side view and a plan view of a form supporting device 1 suitable for carrying out the present invention. This formwork support device 1
Is provided with a formwork holding member 4 for supporting an outer formwork 3 for concrete pouring inside the yoke frame 2, and a winch 5 for suspending the whole above the yoke frame 2.
And a moving wheel 8 which projects inwardly and engages with the reinforcing cut-out 7 of the liner plate 6, and a facing gap adjusting mechanism 9 is arranged between the yoke frame 2 and the moving wheel 8 in the radial direction. It will be done. Further, the mold support device 1
Are arranged around the liner plate 6 (for example, 18 at intervals of 20 °), are positioned by the connecting frame 10 with each other, and have a structure in which the plurality of groups can move in the vertical direction substantially at the same time. There is.

Hereinafter, a process of constructing the concrete side wall 11 using these formwork supporting devices 1 will be described.

"Forming Step of Liner Plate" As shown in FIGS. 1 and 2, the outer surface of the cylindrical liner plate 6 is prevented from being deformed in the vertical direction at intervals in the circumferential direction thereof. A plurality of T-shaped reinforcing cutaways 7 are integrally arranged in a state of extending above the concrete pouring position.

"Hooking process of the yoke frame" From the winch 5, a wire is extended as shown by the chain line (a) in Fig. 1 and connected to the upper part of the reinforcing cut-tee 7 to suspend a plurality of formwork supporting devices 1. To do.

“Supporting process for concrete pouring formwork” While attaching the concrete pouring outer formwork 3 to the formwork holding member 4, between the liner plate 6 and the concrete pouring outer formwork 3, for concrete pouring Cavity 12 is formed. The radial dimension of the cavity 12 is adjusted by the facing distance adjusting mechanism 9 and the connecting frame 10, and at the time of concrete pouring, the spread of the facing distance due to the pressure at the time of concrete pouring is adjusted by the facing distance adjusting mechanism 9 and the connecting frame. It is suppressed by the frame 10.

“Concrete placing process” Concrete placing is performed on the cavity 12 for concrete placing as shown in FIG.

“Movement process of concrete pouring formwork” Next, while loosening the facing distance adjusting mechanism 9 and operating the winch 5, as shown by the arrow and chain line in FIG.
The yoke frame 2 is pulled up, and an outer formwork 3 for concrete pouring, which is integral with the yoke frame 2, is moved upward. At this time, the wire of the winch 5, which originally looked like the chain line (a),
It is shortened as shown by the chain line (b), and is stretched again as shown by the chain line (a) by, for example, supporting it with half of the plurality of winches 5 and switching the other half.

"Supporting process for outer formwork for concrete placement" The facing interval adjusting mechanism 9 is operated to apply the next concrete between the liner plate 6 and the outer formwork 3 for concrete placement at a position above the concrete placement part. A casting cavity 12 is formed.

"Next Concrete Placing Step" Then, the cavitator 12 for the next concrete placing is provided with reinforcing bars 13 and reinforcing bars 14 as necessary, and concrete placing is carried out.

The concrete side wall 11 is constructed by sequentially repeating such steps.

Further, the portion X of FIG. 3 in which the concrete side wall 11 has a straight cylindrical shape is simply moved by the facing distance adjusting mechanism 9 in a straight line in the radial direction of the concrete placing outer formwork 3, Cavity for concrete placement 12
Can be formed and concrete pouring can be continued almost continuously.

On the other hand, in the Y portion of FIG. 3 where the concrete side wall 11 has a tapered shape, the reinforcing cutaways 7 are not parallel to each other. By changing the interval of
The yoke frame 2 can be moved upward along the tapered surface. Furthermore, the outer frame 3 for concrete placement is
If it is possible to change the inner diameter of the cavity by sliding, or if it is possible to insert a new form 15 with different dimensions as shown by the arrow in Fig. 1, from the bottom to the top. , It will be possible to carry out a series of concrete pouring.

These techniques can also be applied to containers, tanks, etc. other than the reactor containment vessel.

[Advantages of the Invention] As described above, according to the present invention, the outer formwork for concrete pouring supported by the yoke frame is raised upward by the progress of the concrete pouring process by utilizing the cut stay of the liner plate. Therefore, the following effects are obtained.

(1) The supporting portion of the outer concrete formwork for concrete pouring is arranged only at the outer side position of the liner plate so that it does not straddle the upper part of the concrete side wall, and the reinforcing cut-tee is extended above the concrete pouring position. Since the liner plate can be arranged in this state and the liner plate can be extended upward, the workability of constructing the concrete wall can be improved.

(2) Since the liner plate is supported by the reinforcing cutouts, the support member for the inner surface of the liner plate and the like can be omitted, and there is no restriction on the height of the liner plate extending above the concrete pouring position, and It is possible to shorten the construction period for the concrete wall by eliminating the limit on the amount of concrete placed.

(3) By placing a liner plate with high installation accuracy as a standard and placing concrete according to this,
It is possible to improve the construction accuracy when constructing a concrete wall.

[Brief description of drawings]

1 and 2 are a side view and a plan view of an essential part showing an example of a formwork supporting device suitable for carrying out the method for constructing a concrete wall in a containment vessel of the present invention, and FIG. 3 is a boiling water type It is a front sectional view showing an example of a reactor containment vessel in a nuclear reactor. 1 ... Form support device, 2 ... Yoke frame, 3 ... Outer form for concrete placing, 4 ... Form holding member, 5
...... Winches, 6 ...... Liner plates, 7 ...... Reinforcing cut ties, 9 ...... Opposing distance adjustment mechanism, 10 ...... Connection frame, 11
…… Concrete side wall, 12 …… Cavity for placing concrete, 15 …… New formwork.

Claims (1)

[Claims] 1. A state in which a plurality of reinforcing cut tees (7) are provided on the outer surface of a cylindrical liner plate (6) and are spaced apart in the circumferential direction thereof so as to prevent vertical deformation of the liner plate. And arranging an outer formwork for concrete placement (3) at an outer position of the liner plate and suspending a yoke frame (2) for supporting the outer formwork for concrete placement on a reinforcing cutout. Cavity for concrete pouring (1) formed between the step and the liner plate and the outer formwork for concrete pouring
2) a step of placing concrete, and a step of moving the yoke frame upward after the concrete placing step to perform the next concrete placing above the concrete placing portion. Construction method of concrete wall in containment vessel.