JPS60152755A - High strength construction of carry-out floor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a high-strength construction method for corrugated floors such as balconies and upstairs hallways constructed by pouring concrete.

(Prior art) Conventionally, as shown in FIG. 1, the construction of the raised floor 1 was performed using precast concrete, in which a snout 2b is erected at the front end of a long base plate 2B of a predetermined width, and a drainage groove 2C is provided on the upper surface adjacent to the snout 2b. A precast formwork 2 is used, and this is attached to the base plate part 2 with supports 3.
A is temporarily fixed so that it is horizontal, and concrete is cast on site together with the floor 4 of the building on top of the base plate part 2a to form cast-in-place concrete WI5, and the precast formwork 2
The floor 1 was formed by integrating with the floor 1. in this case,
The precast formwork 2 and the cast-in-place concrete layer 5 were connected using anchors such as bolts and wires. In such a portable floor 1, the precast formwork 2 becomes a part of the floor 1, so there is no need for a dedicated formwork, and there is no need to grind out the formwork, making construction easy and cost-effective. This has the advantage that it can also reduce the amount of water.

However, such a conventional corrugated floor 1.

The precast formwork 2 and the cast-in-place concrete layer 5 are not completely integrated, but the precast formwork 2 is suspended from the cast-in-place concrete layer 5,
The strength of the raised floor 1 is provided only by the cast-in-place concrete layer 5, and there is a drawback that the strength of the root portion is not sufficient, especially at the base.

In addition, in the conventional corrugated floor 1, the joint between the precast formwork 2 and the cast-in-place concrete layer 5 opens at angles α and β, as shown in FIG. There was a risk that rainwater would enter there, corrode the anchors connecting the two, and that the cyprecast formwork 2 would fall after years of use.

(Object of the Invention) An object of the present invention is to provide a high-strength construction method for a corbelled floor that can significantly improve the strength of the seven-corbelled floor.

(Structure of the Invention) The present invention provides for temporarily fixing a precast formwork having a snout at the tip of the base plate in a direction in which the base plate is horizontal, and casting it on-site on the base together with the floor of the building. In a construction method for a corrugated floor in which a cast-in-place concrete layer is poured and the precast formwork and the cast-in-place concrete layer are integrated to construct a corrugated floor, truss reinforcements are provided on the surface of the precast concrete plate as the precast formwork. The pair of bottom reinforcement sides of the base are buried in the precast concrete plate, and the top side of the tip thereof is made to protrude from the surface of the precast concrete plate, and the tip of the precast concrete plate has a snout, and the front side thereof has a thick Temporarily fix the precast truss plate so that the precast concrete plate is oriented horizontally using a lath plate (Grecas), which has a grooved bottom plate with a flat surface, and attach it to the top bar of the truss bar. The reinforcing bars of the cast-in-place concrete layer are welded and fixed, and in this state, concrete is cast on the precast concrete plate to form the cast-in-place concrete layer, and a part of this cast-in-place concrete layer. This is characterized in that the groove bottom plate portion is overlaid with a raised step portion formed on the groove bottom plate portion, and a groove is formed together with the raised step portion of the nose tip.

According to this construction method, due to the presence of truss bars in the precast truss plates, the stress at the roots of the raised floor can be dispersed, and stress concentration at the roots can be avoided. A high-strength corrugated floor can be obtained by completely integrating the reinforcing bars of the layers (bracing)) with the protruding portions of the truss bars of the lath plate (i) and the precast truss plate, that is, the precast formwork. Also, by joining the two with high strength in this way, the seam can be prevented from opening,
In addition, since the groove bottom plate is horizontally spliced, opening of the seam can be further prevented, corrosion of the truss bars serving as anchors can be prevented, and the service life can be extended.

(Example) Examples of the present invention will be described in detail below with reference to FIGS. 3 and 4. In the present invention, a truss reinforcement 7 is provided on the surface of a precast concrete plate 6 as a precast formwork, and a bottom reinforcement 7g is provided at one end of the base thereof.

T& is buried in the precast concrete plate 6, and the top reinforcement 7 at the tip is supported via the lattice reinforcements 7b, 7b.
The C side is made to protrude from the surface of the precast concrete board 6, and the tip of the precast concrete board 6 is provided with a snout 8, and in front of it is provided with a thick grooved bottom plate part 9 with a flat surface. This precast truss plate 10 uses a precast truss plate 10 in which adjacent truss bars 7 are connected by reinforcing bars 11 by welding, and the reinforcing bars 11 are also raised inside the nose tip 8 for reinforcement. There is.

Such a precast truss plate 10 is temporarily fixed with a support 3 in a direction in which the precast concrete plate 6 is horizontally stretched. Further, the reinforcing bars 11 connecting the truss bars 7 of the precast truss plate 10 are made to protrude into the beams 13 of the building 12, and one end of the reinforcing bars 14 in the nose tip 8 is placed on the planned side of the cast-in-place concrete layer 5. Leave it protruding along its length. The reinforcing bars 15 of the cast-in-place concrete layer 5 are welded and connected to the top bars 7C of each truss bar 7. This reinforcing bar 1
One end (111) of 5 is made to protrude toward the floor 4 side of the building 12.The reinforcing bar 1T in the wall 16 of the building 12 is made to protrude toward the planned portion of the cast-in-place concrete layer 5 by bending its tip.

In this state, when concrete is poured together with the concrete pouring of the floor 4 of the building 12 to form the cast-in-place concrete layer 5, each truss reinforcement T of the lath plate 10 protrudes from the precast concrete layer 5. The parts are embedded together and integrated. 1, a part of the cast-in-place concrete layer 5 is overlaid on the groove bottom plate part 9 as a raised step part 18, and a groove 20 is formed together with the raised part 19 of the nose tip 8. A handrail 21 is installed at the upper end of the nose tip 8. The corrugated floor 1 is thus formed as shown.

Next, the strength of the corrugated floor made by the construction method of the present invention and the corrugated floor made by the conventional construction method was compared, and the following results were obtained.

As a test specimen, the corrugated floor made by the construction method of the present invention is shown in Figures 5 and 6 (in Figure 6, the left half shows the lower end reinforcement, and the right half shows the upper end reinforcement). ), and the corrugated floor made using the conventional construction method is the 7th floor.
[1 (Conventional precast formwork is omitted as it has little to do with strength.) and Figure 8 (In Figure 8, the left half shows the lower end reinforcement, and the right half shows the upper end reinforcement. The structure is shown in (showing the lines).

When such a test specimen was placed in a position with the central beam facing upwards, the lower surfaces of the floor sections on the left and right sides were supported at two points, and a load P was applied to the beams. The load-displacement curve of the corrugated floor made by the construction method of the invention is as shown in Figure 9, and the load-displacement curve of the corrugated floor made by the conventional construction method is as shown in Figure 10. A comparison diagram between envelope A of the load-displacement curve of the corrugated floor made by the conventional construction method and envelope B of the load-displacement curve of the corrugated floor made by the conventional construction method was prepared, and the result was shown in Fig. 11.

As is clear from these figures, it has been proven that the corrugated floor made by the method of the present invention has significantly higher strength than the corrugated floor made by the conventional method.

(Effects of the Invention) As explained above, in the high-strength construction method for a corrugated floor according to the present invention, a precast truss board incorporating truss reinforcements is used as the precast formwork, and the protruding portions of the truss reinforcements of the precast truss board are The reinforcing bars of the cast-in-place concrete layer are welded and fixed, and this part is embedded in the cast-in-place concrete layer, so the stress applied to the roots of the corrugated floor can be dispersed throughout the year, and the corrugated floor can also be constructed. It is possible to completely integrate the precast truss plate and the cast-in-place concrete layer, making it possible to construct a high-strength corrugated floor. In addition, if the precast truss plate and the cast-in-place concrete layer are strongly integrated in this way, the joint between the two will not open, and the cast-in-place concrete layer will have a horizontal joint at the groove bottom plate, so the joint will not open on this side. It is possible to prevent rainwater from entering and extend the lifespan.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a conventional corrugated floor, Fig. 2 is a sectional view showing the open state of the joints of a conventional corrugated floor, and Fig. 3 is an example of a corrugated floor constructed using the construction method of the present invention. A longitudinal cross-sectional view showing,
Figure 4 is a perspective view showing an example of a truss muscle, Figures 5 and 6
The figure is a longitudinal cross-sectional view and a plan view showing the reinforcing condition of a test piece of a corrugated floor made using the construction method of the present invention, and FIGS. A plan view showing the condition of the striations, and Fig. 9 shows the load of the test specimen by the construction method of the present invention.
Displacement curve diagram, Figure 1O is a load-displacement curve diagram of the test specimen by the conventional construction method, and Figure 11 is the envelope A of the load-displacement curve of the specimen by the construction method of the present invention and the load of the specimen by the conventional construction method. - Comparison diagram of the displacement curve with the envelope B; 1... Extruded floor, 3... Support, 4... Building floor,
5... Cast-in-place concrete layer, 6... Precast concrete plate, 7... Truss bar, TIL... Bottom bar, Tb... Lattice bar, 7c... Top bar, 8
... Nose tip, 9 ... Groove bottom plate part, 10 ... Precast truss plate, 11 ... Reinforcement bar, 12 ... Building, 13
...beam. Patent applicant: Toshio Nishi Figure 1 Figure 2 Figure 3 Figure 5 Figure 7 Figure 9 Figure 10 Figure 11

Claims (1)

[Claims] (1) A precast formwork having a snout at the tip of the base plate is temporarily fixed in an orientation where the base plate is horizontal, and a cast-in-place concrete layer is cast on the base together with the floor of the building. In the construction method of a corrugated floor, in which the precast formwork and the cast-in-place concrete layer are integrated to construct a corrugated floor, a pair of truss bars are provided on the surface of the precast concrete plate as the precast formwork at the base thereof. The bottom side of the plate is buried in the precast concrete plate, and the top side of the tip thereof is made to protrude from the surface of the precast concrete plate, and the tip of the precast concrete plate has a snout, and the front side thereof has a flat surface within the thickness. Using a precast truss plate having a grooved bottom plate, the precast lath plate is temporarily fixed in such a manner that the precast concrete section≠; The reinforcing bars of the concrete layer are connected and fixed, and in this state, concrete is poured on the precast concrete plate to form the cast-in-place concrete layer, and a part of the cast-in-place concrete layer is placed in the groove. 1. A high-strength construction method for a corrugated floor, characterized by forming a raised step on the bottom plate part and forming a groove together with the raised step part of the nose.