JPH0777596A - Large scale slab in atomic energy facility and construction thereof - Google Patents

Abstract

PURPOSE:To provide a large scale slab and a construction method thereof in nuclear energy facility in which the construction period can be shortened while reducing the manpower at site. CONSTITUTION:When the thick large scale slab S is constructed in nuclear energy facility, a PC floor plate 1 for lower layer applied with a steel plate 2 having studs 3 on the upper face thereof is prefabricated. Concrete 7 for upper layer is then cast in place using the steel plate 2 as forms. This method eliminates the need of under floor end steel reinforcing work at site, reduces the work for burying metals because they are set in the factory, and reduces the assembling and removing work of forms significantly because the PC floor plate 1 can be used as the forms for placing concrete at the site.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a large slab capable of constructing a large slab having a large thickness in a nuclear facility in a short period of time and a construction method thereof.

[0002]

2. Description of the Related Art Generally, slabs are constructed by assembling supporting works, assembling slab formwork, ceiling surface embedded plates,
It is carried out by repeating the process steps of attaching the penetration sleeve, assembling the slab lower end rebar, assembling the slab upper end rebar, attaching the floor embedding plate, placing concrete, and dismantling the slab formwork / supporting work.

On the other hand, the construction of a slab in a nuclear facility requires extremely high quality, so that the construction work of a steel slaughter pedestal for securely holding rebars and various kinds of buried hardware in place is required. Since the slab thickness is large and the floor height is high, ancillary steps such as temporary work for scaffolding to secure the safety of construction are required in addition to the above eight main steps.

[0004]

However, in the construction of a large slab in a conventional nuclear facility, most of the main process and incidental processes are exhausted by on-site work.
There was a problem that each work type was congested and entangled, the local work was extremely complicated and the construction period was prolonged, and a large number of workers had to be secured.

Therefore, the present invention has been made in view of such conventional problems. By significantly shifting the amount of conventional on-site work to the factory, it is possible to shorten the construction period and reduce the number of on-site workers. The purpose of the present invention is to provide a large-scale slab and a method for constructing it in a large nuclear facility.

[0006]

A large slab of the present invention which achieves the above object has a floor steel plate with studs on the upper surface of a floor PC plate of a lower layer, and a floor cast in situ through the floor steel plate with studs. The upper layer made of concrete is integrated with the floor PC plate of the lower layer. In addition, the method for constructing a large slab of the present invention is a method for constructing a large slab having a large slab thickness consisting of a lower layer floor PC plate and an upper layer cast-in-place concrete. Is provided in advance and is separately formed in advance, an embedded metal fitting is incorporated if necessary, and a steel plate with studs of the floor PC plate is used as a formwork, and the concrete of the upper layer is cast in situ on the upper layer thereof.

[0007]

[Function] A steel plate with studs is used as a structural material in place of the slab lower end rebar that bears the tensile force applied to the slab, and a floor PC plate produced in advance by incorporating this is used as a slab formwork on site. Further, the floor PC plate is pre-installed with a floor through hole and a buried metal object such as a ceiling burying plate necessary for equipment construction, etc., thereby simplifying the on-site work and saving labor of the formwork dismantling work. With the studs attached to the steel plate, the floor PC plate and cast-in-place concrete are integrated, and the strength of the slab can be secured.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show the basic structure of a large slab for a nuclear facility of the present invention. The lower layer of the slab S is a floor PC plate 1 produced at the factory, and a floor steel plate 2 with studs is arranged on the upper surface thereof. On the floor steel plate 2 with studs, a large number of studs 3 are vertically provided at predetermined intervals so as to project vertically. For reinforcement, wire mesh streaks 4 are provided inside the floor PC plate 1, and corner angles 5 are attached to the corners of the floor PC plate 1.

The upper layer of the slab S is composed of cast-in-place floor concrete 7 having a floor upper end streak 6 at the upper portion,
The floor PC plate 1 of the lower layer is firmly integrated with the floor steel plate 2 with studs. In the figure, A represents the slab end, L represents the slab length, W represents the slab width, and T represents the slab thickness. The floor PC slab 1 is manufactured in a factory with the floor steel plate 2 with studs attached to the upper surface and carried into the field.

The above-mentioned FIGS. 3 and 4 are for a floor support made up of existing wall concrete 11, column existing concrete 12, beam concrete 13 (simultaneously placed with the floor), etc. constructed in a local nuclear facility. 3 shows an example of slab S allocation. The floor PC slab 1 is set by placing a wall existing concrete 11 and a column existing concrete 12 which are vertical members on the concrete top, and setting by a method such as on-site welding. The floor PC slab 1 has a length L corresponding to a span length L ₁ in the short side direction between the column existing concrete 12 as shown in FIG. 3, and a width W is a span in the long side direction between the column existing concrete 12. The length L ₂ is divided into several pieces and made into a size suitable for the length of the factory. However, the outer shape can be changed depending on the transportation means of the floor PC plate 1 and the performance of the local lifting machine. After setting the floor PC plate 1, the floor upper end reinforcements 6 shown in FIG. 4 are arranged, and the cast-in-place concrete 7 is placed to construct a floor (slab S) having a composite structure.
In the figure, 8 is a pillar (panel zone) concrete that is simultaneously placed with the floor, and 10 is a field joint of the floor PC plate 1.

FIGS. 5 to 8 show an example of on-site joining of adjacent floor PC plates 1. FIG. 5 shows a case in which the slab S bears a large load, and the floor steel plates 2 with studs that are laterally projected are joined together by butt welding via the backing material 14 to form the joined portion 10, with the studs. The lower part of the floor steel plate 2 is formed by filling and joining grout mortar 16 having the same strength as the cast-in-place concrete 7 between the facing slab ends A using the grout formwork 15.

FIG. 6 shows a structure in which the reinforcing bars 17 are arranged on the adjacent floor PC plates 1 and the floor steel plate 2 with studs is made into a continuous structure and the cast-in-place concrete 7 is poured and joined. The joint 10 is filled with resin mortar. FIG. 7 shows a rebar diameter of 80 which corresponds to the bottom rebar of the slab on the adjacent floor PC plate 1.
The floor steel plate 2 with studs is arranged by arranging the reinforcing bars 17 of d or more, and the floor PC slab 1 is provided with a floor receiving large pulling material (temporary buried shape steel) 18 between the corners. It is welded to the angle 5 and the lower surface of the floor support large pulling material 18 is supported by a large supporting member 19 to fill the cast-in-place concrete 7 and fixed by joining.

In FIG. 8 (a), the adjacent floor PC slabs 1 are each provided with a threaded reed bar 21 for connection having a reinforcing bar diameter of 40d or more, which corresponds to the lower end reinforcing bar of the slab, and the ends thereof are grout type reinforcing bars. While joining with the coupler 22 for joints,
A floor support large pulling material (mainly shaped steel) 23 is arranged and welded and fixed to the corner angle 5, the floor support large pulling material 23 and the rebar joint coupler 22 are welded and fixed, and then the cast-in-place concrete 7 is filled. It is then fixed by joining.

FIG. 8 (b) shows that the adjoining bar 17 having a diameter of the reinforcing bar corresponding to the slab lower end reinforcing bar of 80d or more is arranged in the through hole H provided in the web surface of the floor supporting large drawing member 23 in the adjacent floor PC plate 1. Then, the floor steel plate 2 with studs is made into a continuous structure and the cast-in-place concrete 7 is cast and joined. 8 (a) and 8 (b) are means used for the unsupported construction method.

FIG. 9 and FIG. 10 exemplify the connection between the end portion of the slab S and the precast wall. In both cases, the end of the slab S is fixed by concrete splicing between the existing lower floor concrete 11A and the upper floor concrete 11B. In the case of FIG. 9, the end portion of the floor PC slab 1 in which the reinforcing bars 24 are embedded in advance is placed on the top end portion of the existing wall concrete 11A on the lower floor, and the wall top end corner angle (with anchor) 25
Weld the floor PC version corner angle (with anchor) 5. Further, by connecting the floor PC plate fixing rebar (on-site mounting type) 26 to the end of the PC plate buried rebar 24 via the rebar joint coupler (grout type) 22, the floor PC plate 1
The studded floor steel plate 2 is fixed to the wall. Then, the floor upper end streak 6 is arranged, and the cast-in-place concrete 7 is poured to fix the slab S to the wall. In addition, 29 in a figure is a horizontal wall.

In the case of FIG. 10, instead of the PC plate embedded rebar 24, the rebar coupling coupler 22 and the floor PC plate fixing rebar 26 in FIG. The floor PC plate fixing rebar 30 is attached and piled up and fixed to the wall. FIG. 11 exemplifies the attachment of the slab S and the beam, and in this case also, there are two fixing methods as in the case of fixing the slab S to the wall.

That is, one is a floor steel plate 2 with studs.
PC plate embedded rebar 24 through the rebar joint coupler 22
This is a method of fixing to the beam with the floor PC plate fixing rebar 26. The other is a method of attaching the floor PC plate fixing rebar 30 on the floor steel plate 2 with studs and fixing it on the beam. However,
When pouring the beam and the concrete 7 of the slab S at the same time,
The floor PC version 1 is a large support 1 through the floor PC version pull-up 31.
Support at 9. In FIG. 11, 32 is a beam form (wooden, steel or PC plate form), 33 is a beam reinforcement, and 34 is a beam cast concrete (simultaneous casting with the floor).

FIG. 12 exemplifies the connection between the slab S and the buried metal piece. A ceiling embedding plate (with a stud anchor) 36 and a floor penetrating sleeve 37 are embedded in the floor PC plate 1 at a factory stage, and the floor PC plate 1 is set at a predetermined position on site, and a floor penetrating retrofit sleeve 38. The floor through hole 39 is provided by assembling. 13 (a)-
(C) shows an example of the combination of the floor PC plate 1 and the large drawing material.

FIG. 1 (a) shows an embedded type, and the lower end of the floor support large pulling material 23 is welded to the floor steel plate 2 with studs and is completely embedded inside the slab S. The figure (b) is a semi-exposed type, the middle part of the floor receiving large pulling material 23 is welded to the floor steel plate 2 with studs, a part thereof protrudes from the lower end of the floor PC plate 1, and the rest is of the slab S. It is buried inside. In addition, in this semi-exposed type, the lower end of the floor support large pulling member 23 and the lower end of the floor PC plate 1 may be at the same level. The figure (c) is an exposed type, and is a floor pulling bar 2
The upper end of 3 is welded to the floor steel plate 2 with studs, penetrates through the floor PC plate 1 and is exposed downward.

FIGS. 13D to 13J show an example of joining joist material with the floor-bearing large pulling material 23. (D), (g) (g
Is a right-angled sectional view of d, h is a right-angled sectional view of e, and i is a right-angled sectional view of f) is a type in which a joist 42 is arranged on the upper surface of the steel plate 2 with studs. (E), (h) and (f), (i) in FIG.
Is a type in which a joist 42 is embedded in the lower surface of the steel plate 2 with studs, that is, in the concrete of the floor PC slab 1, as shown in FIG.
(H) is a completely buried type, and FIGS. (F) and (i) are types in which the lower end of the joist 42 is at the same level as the lower end of the floor PC plate 1. FIG. 1J shows the engagement between the floor-bearing hauling material 23 and the joist 42 when the floor-bearing hauling material 23 is not embedded in the floor PC plate 1.

As described above, when the floor PC slab 1 and the floor support large-pulling material 23 are combined, as a general rule, no support is provided. In addition, the end portion of the floor-supporting pulling bar 23 is, in principle, of a wall-mounting type. FIG. 14 shows the connection between the lower end and the wall of the semi-exposed type floor receiving large pulling material 23. 15 and 16 show an example in which the floor PC slab 1 functions as a formwork and bears the pouring load of cast-in-place concrete.

FIG. 15 shows the case of construction by the unsupported construction method.
The figure (a) is applied to a comparatively thin slab S, and the figure (b) is applied to a comparatively thick slab S having a buried type floor support large bar 23. In the former case, when the floor PC slab 1 is manufactured, the reinforcing bars 41 are incorporated into the floor PC slab 1 to increase the load capacity of the casting load P of the cast-in-place concrete, and the construction is carried out without any support work. In the latter case, when the floor PC slab 1 is manufactured, the large acceptance steel material 23 and the joist steel material 42 are incorporated to increase the load capacity of the casting load P of the cast-in-place concrete, and the construction is carried out without any support work.

FIG. 16 shows a case where the construction is carried out by the support method.
FIG. 1A shows a floor PC version 1 in which the wire mesh streak 4 for preventing cracks and the buried type floor receiving big drawing material 23 are incorporated in advance, and the floor receiving big drawing material 23. The construction is carried out by supporting the portion of the burial site of with the large supporting work 19.
In addition, as a method of attaching the floor receiving large pulling material 23, a method in which the upper flange of the large pulling material 23 and the floor steel plate 2 with studs are welded may be used.

In FIG. 1B, the floor PC plate 1 in which the wire mesh streak 4 for preventing cracks is incorporated, but the floor catching pulling material 23 is not incorporated, is carried into the site and is removed. The construction is carried out by being supported by the large-scale supporting work 19 via the floor-bearing large-pulling material 43. The above-mentioned unsupported construction method and supported construction method may be selectively used by selecting the most rational method by combining any one or a plurality of methods depending on the design and construction conditions.

[0025]

As described above, according to the present invention,
When constructing a large slab with a large slab thickness in a nuclear facility, the floor PC plate of the lower layer is pre-formed by arranging steel plates with studs on the upper surface, and the steel plate with studs of the floor PC plate is used as a formwork for concrete of the upper layer. Since it is set to be in-situ, the following various effects can be obtained.

By preliminarily incorporating a steel plate with studs into the floor PC plate instead of the floor bottom reinforcing bars, the on-site rebar assembling work, which has been indispensable in the past, can be halved only by assembling the floor top reinforcing bars. If necessary, embedded hardware such as ceiling embedding plate and floor penetration sleeve can be incorporated into the floor PC plate at the factory production stage,
Their on-site burial work is greatly reduced. In addition, it is possible to eliminate the useless construction of the ceiling surface after placing concrete, which has been conventionally caused by deck plate formwork and the like.

Since the floor PC slab is used in advance as a formwork for cast-in-place concrete, most of the conventional formwork assembly work and formwork disassembly work can be reduced. In addition, the floor bearing support can be easily constructed by no support or large support. From the above, it can greatly contribute to the reduction of the number of local workers and the shortening of the construction period.

Further, by constructing the prefabricated unit construction method using the floor PC plate, the working floor and the lower space can be secured promptly, and both safety and quality are improved. Compared with general steel plate concrete structures, there is an advantage that maintenance measures for steel plates and measures for fire resistance are unnecessary.

[Brief description of drawings]

FIG. 1 is a plan view showing a floor PC plate of the present invention.

FIG. 2 is a cross-sectional view showing the basic structure of the slab of the present invention.

FIG. 3 is a plan view showing an example of slab allocation on site.

FIG. 4 is a sectional view taken along line III-III in FIG.

FIG. 5 is a cross-sectional view of essential parts showing an example of on-site joining of adjacent floor PC plates 1.

FIG. 6 is a cross-sectional view of essential parts showing an example of on-site joining of adjacent floor PC plates 1.

FIG. 7 is a cross-sectional view of essential parts showing an example of on-site joining of adjacent floor PC plates 1.

8 (a) and 8 (b) are adjacent floor PC plates 1 respectively.
FIG. 3 is a cross-sectional view of a main part showing an example of the on-site joining of.

FIG. 9 is a cross-sectional view of an essential part illustrating the joining of the end portion of the slab and the wall that has been pre-cast.

FIG. 10 is a cross-sectional view of an essential part illustrating the joining of the end portion of the slab and the wall that has been pre-cast.

FIG. 11 is a main-portion cross-sectional view illustrating an example of a combination of a slab and a beam.

FIG. 12 is a main-portion cross-sectional view illustrating the connection between the slab and the embedded metal object.

13 (a) to 13 (c) are cross-sectional views of a main part illustrating the combination of the floor PC plate and the large pulling material. (D)-(j) is sectional drawing which shows the example of a joist material attachment with a large pulling material.

FIG. 14 is a cross-sectional view of a main part illustrating the connection between the lower end and the wall of the pulling bar shown in FIG.

15 (a) and 15 (b) are cross-sectional views of essential parts for explaining an example of the unsupported construction method using the floor PC slab of the present invention as a mold.

16 (a) and 16 (b) are each a fragmentary sectional view for explaining an example of a supported construction method using the floor PC slab of the present invention as a mold.

[Explanation of symbols]

 1 Floor PC version 2 Floor steel plate with stud 3 Stud 6 Floor upper end streak 7 Cast-in-place concrete S slab

Claims (2)

[Claims] 1. A floor PC of the lower layer, which has a floor steel plate with studs on the upper surface of the floor PC plate of the lower layer, and an upper layer made of in-situ floor concrete through the floor steel plate with studs.
A large slab in a nuclear facility characterized by being integrated with the plate. 2. When constructing a large slab having a large slab thickness composed of a lower floor PC plate and an upper layer cast-in-place concrete, the lower floor PC plate is formed by arranging steel plates with studs on the upper surface. In addition, a method for constructing a large slab in a nuclear facility is characterized in that the steel plate with studs of the floor PC version is used as a formwork and the upper layer concrete is cast in situ on the upper layer.