JPS60173239A - Deck plate for synthetic 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 deck plate used for a synthetic floor constructed by pouring concrete onto a deck plate.

(Background of the Invention) In a synthetic floor, after the concrete hardens, the deck plate and the concrete 1 work together to bear the applied load. When the composite floor is subjected to a vertical load, due to the difference in the elastic modulus of the concrete and the deck plate, the concrete 1 will peel off in the vertical direction due to the force that tends to shift the concrete 1 against the deck plate surface in the longitudinal direction. A force is generated to try.

By preventing this shift and peeling, the deck plate and concrete work together to withstand the applied load.

In practical use, deck plates for synthetic floors have the following properties.

(a) It must have sufficient yield strength, toughness and rigidity as a synthetic floor.

(b) Since the deck plate bears the weight of the concrete when the concrete is not yet cured, the cross-sectional performance per weight of the deck plate is good.

(c) The quality of the deck plate is ensured and quality control is easy.

(d) Good construction performance.

(e) The deck plate is easy to pack and has a high loading rate. In addition, quality deterioration during transportation and construction is unlikely to occur.

Various deck plates having various cross-sectional shapes have been proposed in pursuit of the above-mentioned performance. Representative examples of these include: (A) A deck plate with enphos provided on its surface.

Utility Model Publication No. 42-7178 (US Pat. No. 3,397,497) CB) A deck plate having an embossed surface and a deformed portion to prevent peeling.

Japanese Patent Publication No. 52-1568, Japanese Patent Publication No. 52-288 (US Patent No. 3812E138) (C) A shear connector made of round steel or the like is welded to the end flange of a deck plate. (So-called reinforcing bar welding type) Japanese Patent Publication No. 52-40503 (0) A type in which concrete is restrained only by an inclined web without providing an enforcer on the surface of the decking plate.

U.S. Patent No. 3f1874213 and so on.

By the way, the present inventors investigated the performance of the above-mentioned various digital plates, and as a result of repeated experiments, the following facts were discovered.

With the embossed deck plate, we expect a synthetic effect from the engagement between the emboss and the concrete. In this type of composite floor structure, when a vertical load P acts on the composite floor 1 as shown in FIG.

Detsuki play 1: The embossing prevents the concrete from shifting against the surface. For this reason, the shear strain energy is locally concentrated and accumulated in the part of the concrete that engages with the embossment, and the mechanical sharkiness caused by the embossment is reduced.
As a result of this action, diagonal cracks C occur in this area as shown in FIG. At the same time as this crack C occurs in the concrete 1 and 3, an edge shift S occurs between the deck plate 5 and the concrete 3. Rub this edge on the synthetic floor 5
When this occurs, deck plays 1 and 5 occur as shown in Figure 2.
Since there is an embossing 7, the concrete 3 deforms the deck plate 5 into a shape pushed out to the height of the embossing 7. In this way, diagonal cracks C in concrete 3
occurs (at the same time, a shift S occurs), and as a result, the synthesis effect is impaired.

In the case of a synthetic bed made of deck plates with only embossing, as shown by the load-deflection curve A in FIG. 3, the point a at which deviation occurs and the maximum load Pa are low, and the bed exhibits poor stickiness.

In addition, in the case of the type with embossing and a deformed part to prevent peeling, since there is a deformed part to prevent peeling, the maximum load PB increases even after the deviation occurs (point b), as shown in the load-deflection curve B in Figure 3. do. However, since the deck plate has already been deformed, its composition effect with concrete is reduced, and it yields in bending as a bending structural material, failing to form a plastic hinge.

Therefore, the load-deflection characteristics of this type of composite floor deviate from the theoretical curve T of bending structural materials, and the toughness deteriorates.

From the above, a synthetic floor structure composed of embossed deck plates undergoes bending yielding, making it difficult to form a plastic hinge, and it is difficult to say that the synthetic floor structure has sufficient strength.

In a type of synthetic floor in which a shear connector such as round steel is welded to one flange of the deck plate, both the peeling force and the shearing force are handled by the shear connector. In addition, in this type of composite floor, the shape composed of deck plates and welded reinforcing bars is thought to have the effect of the stirrup bars of reinforced concrete beams. Furthermore, since the embossing is not on the deck surface, it does not exhibit the deformation behavior described above. Therefore, a bending crank occurs instead of the side crack, forming a plastic hinge.

(See third load-deflection curve C). Therefore, the maximum load,
It is already known that this is a synthetic floor structure with excellent toughness and rigidity. However, since manufacturing involves processing such as welding, it is not economical, and examples of this method are rare. Furthermore, when packing the deck plates for transportation, the reinforcing bars become a hindrance, making it impossible to stack them in a concise manner.

In addition, there is no embossing on the 8 sides of the deck play, and the concrete is restrained only by the inclined web.
Demonstrates excellent synthesis effects. However, this type of deck plate is known to have low cross-sectional performance per deck weight. In addition, in order to pack it into a compact package, the deck plates must be turned over and stacked one on top of the other. In the past, there was also the drawback that it took time and effort to handle the deck plates during shipping and at construction sites.

As mentioned in Section L, various shapes of deck play 1 for synthetic floors have been proposed, but there is still room for improvement in terms of strength and economy, and even better performance is still needed. It is hoped that a new plate will be developed.

(Purpose of the Invention) This invention was made in response to the requests listed in L regarding deck plates for synthetic floors, and provides an economical deck plate for synthetic floors that has high I#N strength and loading rate. This is what I am trying to do.

(Structure of the Invention) In the deck plate for a synthetic floor of the present invention, a horizontal upper flange and a horizontal lower flange are connected via an inclined web so as to form a gutter that widens toward one side and opens. A portion extending from a point above the center of the web to the joining point of the lower flange and the inclined web is provided with a first deformed portion that protrudes outward from the web and extends in the longitudinal direction. The cross-sectional shape is a dovetail groove that opens downward in the center of the deck pullet in the width direction. The deck plate has a second deformed portion extending in the longitudinal direction. The 1ζ flange and the inclined web date deck plate extend flat in the longitudinal direction. That is, no deformed portion such as embossing is provided to prevent displacement.

(Function) The deck plate configured as shown in L strongly restrains concrete only by the first deformed portion of the inclined web and the second deformed portion of the lower flange, without embossing. Therefore, many fine cracks similar to those observed in a bending experiment of reinforced concrete beams appear due to the bending stress caused by the mechanical sharkiing effect caused by the embossing. As a result, even if there is no means to prevent the shear force, many bending cracks occur, and the shear energy is absorbed by the cracks and does not increase. This shows that even frictional adhesion is sufficient to counter the shear force.

Furthermore, it is known that the strength and toughness of concrete increase when it is constrained by its surroundings. In this invention, the first
The deformed part is provided near the flange, and the second deformed part is provided on the lower flange, so that the concrete I is restrained at the lower part of -E. therefore.

The deck plate has a shape that completely restrains the concrete. This shows an effect similar to that of continuously arranging stirrups, and after normal bending cracks and extension, shear occurs for the first time near bending yield, where the opening of the bending crack increases. . Eventually, it forms a plastic hinge and collapses by bending. Therefore, the structure has sufficient toughness.

In terms of rigidity, it also shows the same properties as the reinforcing bar welded type. This means that the occurrence and behavior of bending cracks are the same.

(Example) Figures 4 and 5 show examples of the present invention, respectively. Figure 4 is a perspective view of a deck plate, and Figure 5 is a cross-sectional view of a deck plate on which concrete has been poured. .

In these figures, the deck plate 11 is made of steel strips and consists of an opening flange 13.degree. 17 and an inclined web 25.

The upper flange 13 is provided with a high flange deformed portion 14 in the center thereof so as to form a groove extending in the longitudinal direction.

This top flange deformation portion 14 increases the bending rigidity of the upper two flange 13.

The lower flange 17 is provided with a lower flange deformed portion 18 extending in the longitudinal direction so as to form a dovetail groove opening downward in the central portion. This lower 2 lunge deformation part 1
The concrete 3 engages with the inclined portion 19 that projects sideways. Therefore, the lower flange deformed portion 18 resists peeling of the concrete 3 from the lower flange surface. In addition, the lower flange deformed portion 18 increases the bending rigidity of the upper flange 17 similarly to the case of the upper flange 13.

The upper flange 13 and the lower flange 17 are connected by an inclined web 25. A portion of the inclined web 25 from near its upper end to the point where the inclined web 25 meets the upper flange projects toward the rows generally at right angles to the inclined web surface to form an inclined web deformation portion 26. The plane of the inclined web 25 and the plane of its deformation 26 are essentially parallel. The concrete 3 engages with the side surface 27 of the inclined web deformation portion 28 and is prevented from peeling off from the concrete brake 11.

The deck plate 11 has one flange 13 and an inclined web 2.
m made up of 5 is made up of one mountain. Both sides of the deck plate 11 are respectively formed into lower flanges 17, one end of which is formed into a hook-shaped curved part 20, and the other end formed into a two-shaped curved part 21. , a plurality of deck plates 11 are connected by bringing the side edges of adjacent ones together, but at this time, the two adjacent curved parts 20, 2
1 are engaged to form a lower flange deformed portion 18.

The deck plate 11 shaped like two legs is continuously manufactured by roll forming.

Table ff11 shows an example of the dimensions of a deck plate formed like two legs. The symbols in Table 1 are shown in FIG.

The dimensions of the double deformed portions 18 and 28 are determined to sufficiently resist peeling of the concrete 3 from the deck surface 11. Desired values for these dimensions are as follows.

30mm≦C≦40mm, lomm≦d≦2011
1m.

10mm≦e≦H/2, 8mm≦f≦15).

40'(α≦80",55@≦β≦65")
- It is not limited to the above embodiments. For example, the lower flange deformed portion 14 may be omitted, and one deck plate 11 may have three or more ridges. Further, depending on the width of the flange 17, a plurality of deformed portions 18 may be provided.Furthermore, the shape of the upper flange deformed portion 14 may be changed
Similar to the one in 7, it may be in a spiral shape.

(Effects of the Invention) The deck plate of the present invention is designed to prevent concrete from peeling only with two deformed portions of 18°2G, and is not designed to prevent concrete from shifting by embossing or the like. Therefore, shear strain energy is not locally concentrated and accumulated in the part of the concrete that comes into contact with the embossing, etc., and diagonal cracks do not occur, and excellent strength is exhibited.

In addition, since the deck plate 11 of the present invention has a gutter shape that widens upward and opens, it has a high cross-sectional performance per weight, and can be made compact by stacking the deck plates 11 with their valleys aligned. It can be packaged without compromising quality.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram illustrating shear failure of a conventional deck plate for synthetic floors, Fig. 2 is a cross-sectional view of a part of a synthetic floor illustrating deformation of a conventional deck plate for synthetic floors, and Fig. 3 shows various types of deck plates. Figures 4 and 5 are diagrams comparing the deflection-load characteristics of deck plates with cross-sectional shapes, each showing an example of the present invention. Figure 4 is a perspective view of the deck plate, and Figure 5 is A cross-sectional view of the deck plate on which concrete has been poured, and FIG. 6 are explanatory diagrams of symbols indicating the dimensions of the deck plate. 1...Deck plate, 3...Concrete 5...
・Deck plate, 7... Emboss, 11... Deck plate, 13... Upper flange, 17... Lower flange, 18... Deformed part, 25... Inclined web,
2B...Deformed part. Patent applicant Representative patent attorney Tomoyuki Yafuki (one idiot) Figure 1 Figure 2

Claims (1)

[Claims] In a deck plate in which a second flange and a horizontal lower flange are connected via an inclined web, the point nearer J- from the center of the inclined web The part from 1 to the joint point of the second flange and the inclined web is provided with a first deformed part that protrudes outward with respect to the web and extends in the longitudinal direction of the decking plate. has a second deformed portion that opens downward and has a dovetail groove shape and extends in the longitudinal direction of the deck plate, and the upper and lower flanges and the inclined web extend flatly in the longitudinal direction of the deck plate. A deck plate for synthetic floors.