JPH0425387B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for constructing temporary openings in earthquake walls of nuclear reactor buildings and the like.

(Prior Art) Numerous temporary openings are provided in nuclear reactor buildings and the like during construction to allow equipment to be brought in.

Generally, when constructing a temporary opening in the building, as shown in Figures 7 and 8, a temporary opening a is created that has an opening width l _p that is larger than the width l _e necessary for bringing in equipment for reinforcing reinforcement. , reinforcing bars c of existing shear wall part b
After the projecting end and the reinforcing bar d in the temporary opening a are joined by a mechanical joint such as a screw joint e or a pressure joint, a formwork is assembled and concrete is poured. Further, as shown in FIGS. 9 and 10, a coupler may be embedded in the joint surface of the inner periphery of the temporary opening and the joint may be performed using a mechanical joint.

(Problems to be Solved by the Invention) In the conventional construction method, the joint reinforcing bars of the existing shear wall protrude from the concrete joint surface of the shear wall into the temporary opening, which is dangerous, and the reinforcing bars Crowded areas and Figures 9 and 10
In the case shown in the figure, the coupler is embedded, so a counterpart is required to take the torque, and the tightening nut alone cannot take the reaction force and cannot apply sufficient torque to the threaded joint of the reinforcing bar in the temporary opening. Also, if the temporary opening is close to the wall and the equipment when closed, it is difficult to bring in temporary materials, making it difficult to dismantle the formwork.

(Means for Solving the Problems) The present invention has been proposed for the purpose of solving these problems and providing a construction method that is safe and easy to perform and has high structural reliability. A plate waste form with the reinforcing steel ends of the shear wall anchored is placed along the inner circumferential joint surface of the temporary opening of the shear wall, and when the temporary opening is closed, a plate waste form is installed. This invention relates to a method for constructing a temporary opening in a seismic wall, which is characterized in that a pair of front and back steel plates that also serve as wall formwork are stretched across the walls, and concrete for the temporary opening is poured into each of the steel plates.

(Function) and (Effects of the Invention) As described above, in the present invention, the steel plate is made of a plate to which the reinforcing bar end of the shear wall of a nuclear reactor building, etc. is anchored along the inner peripheral joint surface of the temporary opening of the shear wall of a nuclear reactor building, etc. A waste formwork is installed, and shear wall concrete is poured into the formwork.

Therefore, when sealing the temporary opening, a pair of steel plates for both the front and back wall forms are stretched between the plate molding forms anchored to the joint surface of the shear wall, and concrete is poured into the steel plates. Since the temporary opening is integrated into the shear wall, the joint reinforcing bars of the shear wall do not protrude from the joint surface into the temporary opening, and construction safety is maintained. Furthermore, there is no need to provide an opening larger than that necessary for carrying in equipment, and construction costs are reduced. Furthermore, since the waste formwork is directly buried in the poured concrete of the temporary opening, there is no need to dismantle the joint formwork in an overcrowded reinforcement.

Furthermore, according to the present invention, the concrete for the temporary opening is poured between the pair of steel plates that also serve as wall formwork.
Overcrowded reinforcement is eliminated, dense concrete is placed, and safety as a concrete member is improved. In this case, by increasing the thickness of the steel plate, it can be used as a structural material and the amount of reinforcing bars used can be reduced. Furthermore, since the waste formwork is processed in a factory, the construction accuracy of the entire wall is increased and the quality is improved.

In addition, by pouring concrete to seal the temporary openings between the front and back steel plates, construction can be easily carried out even when equipment and walls are in close proximity and it is difficult to bring in temporary materials or dismantle formwork. can. In addition, since a pair of steel plates for both the front and back wall formworks are stretched between the plate molding forms arranged along the inner circumferential joint surface of the temporary opening, there is no need for equipment to penetrate through this stretched portion. When holes are provided, holes are drilled at corresponding positions in the pair of front and back steel plates, a sleeve made of steel plate is erected from the hole to the hole, and the pair of steel plates and the sleeve are welded, If a through-hole for the equipment is provided in the tension section, the steel materials can be joined simply by welding, which makes construction extremely easy.Also, the installation of embedded metal fittings for equipment installation can be done in the steel plate formwork. Because it can be installed simply by welding, the construction is extremely easy.Especially, the construction of embedded metal fittings for equipment installation is especially common in the construction work of nuclear reactor buildings, etc., so the effect is extremely large. Become.

In addition, in construction work for nuclear reactor buildings, etc., a large number of embedded metal fittings for installing equipment are attached to the formwork, so the weight of the metal fittings becomes large, and therefore the resistance to applied force is greater than that of plywood formwork. This makes steel plate formwork extremely effective.

Also, wait for the concrete placed between the front and back steel plates, which are also used as wall forms, to dry, stretched between the plate casting forms placed along the inner circumferential pouring surface of the temporary opening. Since the outer surface of the steel plate can be coated with radiation-resistant paint, the painting work can be completed at an early stage.

Furthermore, since the joint of the temporary opening is restrained by the surrounding waste forms and earthquake-resistant walls, when shearing force occurs in the joint, there is almost no opening deformation in the direction perpendicular to the joint. In addition, since slipping is less likely to occur, the strength of the joint is improved.

(Example) The present invention will be described below with reference to the illustrated embodiments.

A plate molding form 1 for pouring concrete for the shear wall B is arranged along the inner circumferential joint surface of the temporary opening A of the shear wall of a nuclear reactor building, etc., and the shear wall B is placed in the same mold form 1.
A temporary opening A is formed by fixing the ends of the threaded reinforcing bars 2 through nuts 3 and pouring concrete for the shear wall.

When sealing the temporary opening A, mounting pieces 4 are welded to the front and back inside surfaces of the waste formwork 1, and a pair of front and back wall formwork steel plates 5 are placed between each mounting piece 4 of the opposing waste formworks 1, 1. to weld. Note that a large number of studs 6 are erected on the steel plate 5.

Next, concrete 8 is placed through a sheath 7 that communicates with the temporary opening A provided in the slab C to seal the temporary opening A.

The reinforcing bars 9 around the temporary opening A are overlapped with the steel plate 5 as shown in FIG.
Alternatively, as shown in FIG. 4, the vertical reinforcement 9 may be a threaded reinforcing bar and be fastened to the peripheral steel plate 1' with nuts 10.

Since the illustrated embodiment is configured as described above, the stress of the horizontal reinforcement 2 of the shear wall B is transmitted to the steel plate 5 via the waste form 1, and the concrete joint of the temporary opening A is Surrounding plate discard formwork 1
It is restrained by the shear wall B, and therefore, when shear force is generated at the joint, there is almost no opening deformation in the direction perpendicular to the joint, and it is difficult to cause slippage, so it is expected to have a strong strength as a joint. Ru.

In addition, since the reinforcing bars 2 of the shear wall B portion are fastened to the plate molding frame 1 with nuts 3, the reinforcing bars 2
does not protrude into the temporary opening A, which improves construction safety, and eliminates the need to make the temporary opening A larger than necessary for carrying in equipment for reinforcing joints, further reducing overcrowding. There is no need to dismantle the joint formwork inside the reinforcement.

Furthermore, a pair of steel plates 5 for both front and back wall formworks are disposed between the opposed waste formworks, and concrete 8 is poured between the steel plates to seal the temporary opening, so that the equipment and the wall can be separated. Construction can be easily carried out even when it is difficult to carry in temporary construction materials or dismantle formwork due to close proximity to
By increasing the thickness of the steel plate 5, it can be used as a structural material, so the amount of reinforcing bars can be reduced. Moreover, dense reinforcement arrangement within both steel plates 5 is eliminated, and dense concrete can be placed. Furthermore, during temporary opening closing work, special consideration must be given to dustproofing and waterproofing the equipment, and by pouring concrete using steel plates as formwork, water during concrete pouring and dry moisture during curing are eliminated. At the same time, the amount of dust caused by sanding during the preparation of the base for painting has been significantly reduced. Since a steel plate that also serves as a frame is stretched, if a through hole for the equipment is to be provided in this stretched part, holes should be drilled at corresponding positions in the front and back steel plates, respectively.
If a sleeve made of steel plates is installed from hole to hole, the pair of steel plates and the sleeve are welded, and a through hole for the equipment is provided in the stretched portion, the steel materials can be simply welded together. It is extremely easy to install because it can be joined, and the installation of embedded metal fittings for equipment installation is also extremely easy because it can be installed simply by welding since it is installed on the steel plate formwork. Since the construction of embedded metal fittings for mounting is particularly common in construction work for nuclear reactor buildings, etc., the effect thereof is extremely large.

In addition, in construction work for nuclear reactor buildings, etc., a large number of embedded metal fittings for installing equipment are attached to the formwork, so the weight of the metal fittings becomes large, and therefore the resistance to applied force is greater than that of plywood formwork. The steel plate type is extremely effective.

In addition, drying of the concrete poured between the front and back pairs of steel plates that are also used as wall forms stretched between the plate casting forms arranged along the inner peripheral pouring surface of the temporary opening. The method of the present embodiment has many advantages, such as the ability to apply radiation-resistant paint to the outer surface of the steel plate, allowing the painting work to be completed at an early stage.

Although the present invention has been described above with reference to embodiments, the present invention is, of course, not limited to such embodiments, and can be modified in various ways without departing from the spirit of the present invention. .

[Brief explanation of drawings]

Fig. 1 is a front view showing the implementation status of one embodiment of the method for constructing temporary openings in nuclear reactor buildings, etc. according to the present invention, Fig. 2 is its cross-sectional plan view, and Figs. 3 and 4 are its longitudinal sections, respectively. Figure 5 is an enlarged cross-sectional view, Figure 6 is a cross-sectional view.
The figure is a detailed view of the part shown in Figure 5, Figures 7 and 8 are a front view and longitudinal side view showing the implementation status of the conventional method, respectively, and Figures 9 and 10 are each of the conventional construction method. It is a front view and a vertical side view showing the implementation situation. A... Temporary opening, B... Earthquake-resistant wall, 1... Waste formwork, 2... Rebar, 3... Nut, 5... Wall formwork steel plate, 7... Sheath, 8... Concrete.

Claims (1)

[Claims] 1. A plate waste form to which the reinforcing steel ends of the shear wall are anchored is placed along the inner peripheral joint surface of the temporary opening of the shear wall, and when the temporary opening is closed, the plate form is placed between the waste forms. A method for constructing a temporary opening in a seismic wall, characterized by setting up a pair of steel plates that also serve as wall formwork on the front and back, and pouring concrete for the temporary opening within each steel plate.