JPH036729Y2 - - Google Patents

Description

[Detailed description of the invention] A. Field of industrial application The invention relates to precast reinforced concrete plates.

B. Prior Art Conventionally, as shown in Fig. 3 for a precast reinforced concrete version, truss reinforcements 3 are fixed to the lower end reinforcements 1 and 2 so as to protrude upward, and the upper and lower surfaces of the lower end reinforcements 1 and 2 and the The periphery is thinly covered with concrete 4 and the upper half of the truss reinforcement 3 protrudes above the concrete surface, or as shown in FIG.
There is one in which the concrete is buried in thick concrete 4.

C. Problems to be solved by the invention In the former of the above-mentioned conventional methods, this is used as a formwork to pour cast-in-place concrete on the top surface, but the form is long. If the distance between the fulcrums is long, cracks will occur in the middle, and in order to prevent this, it is necessary to provide fulcrums in the middle, so there is a problem that it is not possible to form a long plate. In the latter case, although there are fewer problems as mentioned above, on the other hand, the connection between the plate and other members is by welding using a partially exposed joining metal plate, so the integrity of the joint part may be affected. There is a problem with the lack of rigidity. Therefore, the present invention aims to solve the above-mentioned problems by proposing a precast reinforced concrete slab that compensates for the disadvantages of both and combines the advantages of both.

D. Means for Solving the Problems In order to solve the above-mentioned problems, the present invention forms the main body part 7 as a relatively thick concrete slab, and the supporting end part 9 is made of a concrete plate with no upper surface. The main body part 7 is formed on a thin concrete slab with a
and lower end reinforcements 12, 1 in the respective lower parts of the bearing end 9.
3 is buried, and upper end reinforcements 14, 1 are buried in the upper part of the main body part 7.
5 is buried, and a part of the upper end reinforcements 14 and 15 is extended and exposed in the concrete missing part 8 at the support end 9, and the exposed upper end reinforcement is connected to the lower end reinforcement with a connecting steel material. This is a characteristic feature.

E. Function: When the precast concrete slab of the present invention is erected on site by appropriate means and the supporting members 17 such as columns are cast with cast-in-place concrete, the cast-in-place concrete is placed in the precast concrete slab. Concrete is poured into the missing part 8 in one piece. As a result, the joint between the precast concrete slab and the supporting member such as a column is integrated, and its rigidity is increased.

F. Example The example shown in FIGS. 1 and 2 will be described. 7 is the main part of the precast concrete slab, and its thickness is such that when the slab is formed into a long length and is supported and erected at both ends, the maximum bending moment is applied (center part). It is formed to have a cross-sectional area that has enough strength to prevent stress fracture. Reference numeral 8 denotes a concrete cutout section, which is formed by cutting out the upper half of the concrete at the support end 9 of the plate. The surface is roughened to increase adhesion. 12,1
3 is the lower end reinforcement arranged vertically and horizontally. 14,15
is the upper end reinforcement arranged vertically and horizontally. Both ends 14a, 14a of the longitudinal reinforcement 14 of the upper end reinforcement protrude into the concrete cutout 8. 16 is a truss bar located in the concrete cutout 8;
Its lower part is buried in the support end 9 of the plate together with the lower chord reinforcement 16a and is connected to the lower end reinforcement 12, and its upper part is exposed in the concrete cutout 8 together with the upper chord reinforcement 16b and is connected to the longitudinal reinforcement 14 of the upper end reinforcement. Projecting end 1
It is fixed to 4a. Note that the truss reinforcement 16 may be made of other steel as long as it connects the upper end reinforcement 14 and the lower end reinforcement 12.

Next, in order to erect the plate on site, first the plate is
The supporting end portion 9 is held by shoring or the like so that it is located within the joint of a supporting member 17 such as a column cast on site. Next, as shown in FIG. 2, the support member 17 is cast with cast-in-place concrete, and at the same time, the cast-in-place concrete is poured into the concrete cutout 8 in the slab. Concrete part 1 placed in this concrete missing part 8
7a firmly adheres to the plate due to the rough surfaces of the bottom surface 10 and the rising wall 11. Further, both ends 14a of the longitudinal reinforcement 14 of the upper end reinforcement and the truss reinforcement 15 are buried in the concrete portion 17a, so that the plate and the support member 17 are firmly joined.

G. Effects of the invention As described above, in the present invention, the main body is formed into a relatively thick concrete slab, which increases its strength, makes it possible to form a precast concrete slab with a long distance between supporting points, and makes it possible to form a precast concrete slab with a long supporting point. Because the concrete missing part and the connecting steel material were exposed in that part,
By integrally pouring the concrete in the supporting member of cast-in-place concrete into the concrete cutout, the joint between the plate and the supporting member is firmly integrated, and the rigidity is increased. Therefore, it is possible to construct a room with a wide space using a long and highly safe precast reinforced concrete slab.

[Brief explanation of the drawing]

Fig. 1 is a side sectional view showing an embodiment of the present invention;
The figure is a side sectional view showing an installed state, and FIGS. 3 and 4 are side sectional views showing two examples of conventional structures. 7... Main body part, 8... Concrete missing part, 9... Bearing end part, 12, 13... Lower end reinforcement, 14, 15... Upper end reinforcement, 16... Truss reinforcement which is a connecting steel material.

Claims (1)

[Scope of utility model registration request] The main body part 7 is formed of a relatively thick concrete slab, and the bearing end part 9 is formed of a thin concrete slab with no concrete on the upper surface thereof, and each of the main body part 7 and the bearing end part 9 is There is a lower end reinforcement 1 in the lower part.
2 and 13 are buried, and the upper end reinforcement 1 is buried in the upper part of the main body part 7.
4, 15 are buried, and the upper end reinforcing bars 14, 1 are buried in the concrete missing part 8 at the support end 9.
5. A precast reinforced concrete plate characterized by extending and exposing a part of 5 and connecting the exposed upper end reinforcement to the lower end reinforcement with a connecting steel material.