Deck plate

Abstract

The present invention provides a deck plate having an end-closed portion formed by crushing the lower flange, which can improve the initial rigidity of the end-closed portion. [Solution] The deck plate 1 according to the embodiment has an upper flange 11 and a lower flange 12, and an end closed portion 2 formed by crushing the end 1a side in the longitudinal direction from the lower flange 12 side, wherein the upper flange 11 has an embossed portion 3 that protrudes upward at a position spaced apart in the width direction from the end closed portion 2.

Description

TECHNICAL FIELD

[0001] The present invention relates to a deck plate that has an upper flange and a lower flange, and has an end closed portion formed by crushing the end portion side in the longitudinal direction from the lower flange side.

BACKGROUND ART

[0002] As a technique related to a deck plate having an end closed portion formed by crushing the longitudinal end, for example, Patent Document 1 is disclosed. In Patent Document 1, horizontal crest surfaces and trough surfaces are continuous with inclined surfaces to form a trapezoidal corrugated cross-sectional shape, and engaging portions for engaging adjacent deck plates with each other are provided on both side edges in the deck plate width direction. An inverted end-closed type deck plate is disclosed, which is provided with a closed-end beam mounting portion formed through an inclined portion by crushing the longitudinal end portion of the deck plate from the trough surface side, at the height position of the crest surface.

PRIOR ART DOCUMENTS

PATENT DOCUMENTS

[0003]

PATENT DOCUMENT 1

SUMMARY OF THE INVENTION

PROBLEMS TO BE SOLVED BY THE INVENTION

[0004] However, in the deck plate as in Patent Document 1 which has an end closed portion formed by crushing the lower flange, the neck-buckling strength of the end closed portion is lower than the strength of the deck plate, and there is a concern about neck buckling at the end closed portion.

[0005] The present invention has been made in view of the above circumstances, and an object thereof is to provide a deck plate having an end closed portion formed by crushing a lower flange, the deck plate being capable of improving the initial rigidity of the end closed portion.

MEANS FOR SOLVING THE PROBLEMS

[0006] The deck plate according to the present invention has an upper flange and a lower flange, and an end closed portion formed by crushing the end in the longitudinal direction from the lower flange side, wherein the upper flange has an embossed portion that protrudes upward at a position spaced apart in the width direction from the end closed portion. [Effects of the Invention]

[0007] According to the present invention, the upper flange has an embossed portion that protrudes upward at a position spaced apart in the width direction from the end closing portion. This improves the initial rigidity of the end closing portion. As a result, the neck-bending resistance of the end closing portion is improved, and neck-bending at the end closing portion can be suppressed. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a cross-sectional view showing the central portion of the deck plate in the longitudinal direction according to the first embodiment. [Figure 2] Figure 2 is a side view showing the end closing portion of the deck plate according to the first embodiment. [Figure 3] Figure 3 is a cross-sectional view showing the central portion of the deck plate in the longitudinal direction according to the second embodiment. [Figure 4] Figure 4 is a cross-sectional view showing the central portion of the deck plate in the longitudinal direction according to the third embodiment. [Figure 5] Figure 5(a) is a side view showing the end closing section of deck plate No. 1, and Figure 5(b) is a side view showing the end closing section of deck plate No. 2. [Figure 6] Figure 6(a) is a side view showing the end closing section of deck plate No. 3, and Figure 6(b) is a side view showing the end closing section of deck plate No. 4. [Modes for carrying out the invention]

[0009] Some embodiments of this invention will be described below with reference to the drawings.

[0010] (First Embodiment) As shown in Figures 1 and 2, the deck plate 1 has an upper flange 11, a lower flange 12, a web 13, and an end closing portion 2. The upper flange 11 and the lower flange 12 are formed substantially horizontally. The web 13 is continuous with the upper flange 11 and the lower flange 12.

[0011] The deck plate 1 has a trapezoidal corrugated cross-sectional shape formed by a web 13 that is inclined and continuous with the horizontal upper flange 11 and lower flange 12. The deck plate 1 has engaging portions 14 and 15 on both sides of its widthwise edge for engaging adjacent deck plates 1 with each other. The engaging portion 14 of one deck plate 1 engages with the engaging portion 15 of the adjacent deck plate 1, allowing the deck plates 1 to be engaged with each other.

[0012] A projection 11a is formed in the center of the upper flange 11 in the width direction, projecting downward. The projection 11a extends in the longitudinal direction of the deck plate 1. The projection 11a can increase the rigidity of the upper flange 11.

[0013] A protruding ridge 12a is formed in the center of the lower flange 12 in the width direction, projecting upward. The protruding ridge 12a extends in the longitudinal direction of the deck plate 1. The protruding ridge 12a can increase the rigidity of the lower flange 12.

[0014] The deck plate 1 is a deck plate for a composite floor slab that, for example, bears the load together with concrete (not shown). A stepped portion 13a is formed in the web 13. The stepped portion 13a facilitates the integration of the concrete, which has hardened after being cast, with the deck plate 1.

[0015] The deck plate 1 is a so-called reverse end-closed type deck plate, in which the lengthwise end 1a side is crushed from the lower flange 12 side, and the flat portion 22 of the end close portion 2 is aligned with the height position of the upper flange 11 via the inclined portion 21 of the end close portion 2. The length of the deck plate 1 in the length direction is, for example, about 3.4 m. The length of the deck plate 1 in the length direction is approximately 1 m or more and 10 m or less.

[0016] The inclined portion 21 has a lengthwise end 21a and an end 21b of the deck plate 1. The flat portion 22 is placed on a beam (not shown) of the structure.

[0017] The upper flange 11 has an embossed portion 3 protruding upward at a position spaced apart in the width direction from the end close portion 2. That is, the end close portion 2 and the embossed portion 3 are arranged to overlap when viewed from the width direction of the deck plate 1.

[0018] The embossed portion 3 extends in the length direction of the deck plate 1. The embossed portion 3 is spaced apart from the lengthwise end 1a of the deck plate 1. The embossed portion 3 has a start end 3a at the end on the side of the end 1a, and a terminal end 3b at the end opposite to the start end 3a. The length of the embossed portion 3 (the length from the start end 3a to the terminal end 3b) is defined as L3.

[0019] The start end 3a of the embossed portion 3 is, for example, arranged at a position spaced apart in the width direction from the flat portion 22 of the end close portion 2. In the present invention, the start end 3a of the embossed portion 3 may be arranged at a position spaced apart in the width direction from the inclined portion 21 of the end close portion 2, for example.

[0020] The terminal end 3b of the embossed portion 3 is, for example, arranged at a position spaced apart in the width direction from the inclined portion 21 of the end close portion 2. In the present invention, the terminal end 3b of the embossed portion 3 may be arranged closer to the center in the length direction than the end 21b of the inclined portion 21, for example. That is, the terminal end 3b of the embossed portion 3 may be arranged at a position spaced apart in the width direction from the lower flange 12.

[0021] The embossed portions 3 are arranged in a row, one or more in the width direction of the deck plate 1, on the upper flange 11.

[0022] Let L2 be the length of the end-close portion 2 in the longitudinal direction of the deck plate 1, L21 be the length of the inclined portion 21 of the end-close portion 2, and L22 be the length of the flat portion 22 of the end-close portion 2. The length of the end-close portion 2 L2 = length of the inclined portion 21 L21 + length of the flat portion 22 L22.

[0023] Let P be the distance from the end 1a of the deck plate 1 to the end 3b of the embossed portion 3. In this invention, it is preferable that P / L2 × 100 ≥ 66.1. Let P / L2 × 100 be the embossing ratio Z1.

[0024] Let Q be the length from the end 21a of the inclined portion 21 to the end 3b of the embossed portion 3. In this invention, it is preferable that Q / L21 × 100 ≥ 53.3. Let Q / L21 × 100 be the overlap ratio Z2 of the inclined portions.

[0025] In this embodiment, the upper flange 11 has an embossed portion 3 that is spaced apart in the width direction from the end closing portion 2 and protrudes upward. This improves the initial rigidity of the end closing portion 2. As a result, the neck-bending resistance of the end closing portion 2 is improved, and neck-bending at the end closing portion 2 can be suppressed.

[0026] In this embodiment, when the length of the end-close portion 2 in the longitudinal direction of the deck plate 1 is L2, and the length from the end 1a in the longitudinal direction of the deck plate 1 to the end 3b of the embossed portion 3 is P, then P / L2 × 100 ≥ 66.1 is satisfied. This further improves the initial rigidity of the end-close portion 2. As a result, the neck-bending resistance of the end-close portion 2 is further improved, the neck-bending resistance of the end-close portion 2 exceeds the resistance of the deck plate 1, and neck-bending at the end-close portion 2 can be suppressed more reliably.

[0027] (Second Embodiment) Next, the deck plate 1 in the second embodiment will be described. Detailed explanations of the configuration, which is the same as in the embodiment described above, will be omitted. As shown in Figure 3, the deck plate 1 has a horizontal upper flange 11 and a lower flange 12 that are formed continuously by a web 13.

[0028] The webs 13 on both sides of the lower flange 12 extend vertically at their upper ends and contact each other, and are inclined in a direction that separates them at their lower ends. An engaging portion 14 is formed on the web 13 at one end of the deck plate 1 in the width direction. An engaging portion 15 is formed on the web 13 at the other end of the deck plate 1 in the width direction. The engaging portion 14 of one deck plate 1 engages with the engaging portion 15 of the adjacent deck plate 1, allowing the deck plates 1 to be engaged with each other.

[0029] (Third embodiment) Next, the deck plate 1 in the third embodiment will be described. Detailed explanations of the configuration, which is the same as in the embodiments described above, will be omitted. As shown in Figure 4, the deck plate 1 has a horizontal upper flange 11 and a lower flange 12 that are formed continuously by a web 13.

[0030] A projection 11a is formed in the center of the upper flange 11 in the width direction, projecting upward by embossing or the like. Multiple projections 11a are formed extending in the width direction of the deck plate 1 and spaced apart in the longitudinal direction. The rigidity of the upper flange 11 can be increased by the projections 11a.

[0031] The webs 13 on both sides of the lower flange 12 extend vertically at the top and contact each other, and are inclined in a direction that separates them at the bottom. An engaging portion 14 is formed at one end of the deck plate 1 in the width direction. An engaging portion 15 is formed at the other end of the deck plate 1 in the width direction. The engaging portion 14 of one deck plate 1 engages with the engaging portion 15 of the adjacent deck plate 1, allowing the deck plates 1 to be engaged with each other.

[0032] Although some embodiments of this invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. Furthermore, these embodiments can be combined as appropriate. In addition, this invention can be implemented in various novel forms other than those described above. Therefore, each of the above embodiments can be omitted, replaced, or modified in various ways without departing from the spirit of this invention. Such novel forms and modifications are included in the scope and spirit of this invention, as well as in the claims and equivalents of the claims. [Examples]

[0033] In the example, a bending test was performed using a reverse-end closed type deck plate specimen to confirm the initial rigidity of the end-closed portion 2 and whether or not neck bending occurred. The loading method was four-point bending. The end-closed portion 2 was formed by crushing the lower flange sides at both ends in the longitudinal direction of the deck plate. The shape of the end-closed portion 2 is shown in Tables 1 and 2. The embossed portion 3 is positioned on the upper flange 11, spaced in the width direction from the end-closed portion 2, with the starting point 3a of the embossing being 25 mm from the end 1a of the deck plate 1. As an example of a specimen, Figures 5 and 6 show the vicinity of the end-closed portion 2 of specimens No. 1 to No. 4.

[0034] For specimens No. 1 to No. 16, a 75mm high deck plate manufactured by Nippon Steel Construction Materials Co., Ltd. was used. For specimens No. 1 to No. 16, the length L2 of the end closing section 2 was set to 310mm, and the length (total length) of the deck plate 1 was set to 1500mm. The thickness of the deck plate was set to 1.0mm and 1.2mm. The width of the embossed section 3 was set to 14mm.

[0035] As shown in Table 1, the length L3 of the embossed portion 3 was mainly varied in test specimens No. 1 to No. 8. Specifically, in test specimens No. 1 and No. 5, the length L3 of the embossed portion 3 was set to 120 mm. In test specimens No. 2 and No. 6, the length L3 of the embossed portion 3 was set to 180 mm. In test specimens No. 3 and No. 7, the length L3 of the embossed portion 3 was set to 240 mm. In test specimens No. 4 and No. 8, the length L3 of the embossed portion 3 was set to 300 mm. In addition, in test specimens No. 1 to No. 8, the height H of the embossed portion 3 was set to 4 mm. In test specimens No. 1 to No. 8, four embossed portions 3 were arranged in the width direction on both the end 1a side and the other end 1a side of one upper flange 11.

[0036] [Table 1]

[0037] As shown in Table 2, the height H of the embossed portion 3 was mainly varied in test specimens No. 9 to No. 16. Specifically, in test specimens No. 9 and No. 13, the height H of the embossed portion 3 was set to 10 mm. In test specimens No. 10 and No. 14, the height H of the embossed portion 3 was set to 8 mm. In test specimens No. 11 and No. 15, the height H of the embossed portion 3 was set to 5 mm. In test specimens No. 12 and No. 16, the height H of the embossed portion 3 was set to 0 mm (no embossing). In addition, in test specimens No. 9 to No. 11 and No. 13 to No. 15, the length L3 of the embossed portion 3 was set to 300 mm. In test specimens No. 9 to No. 11 and No. 13 to No. 15, two embossed portions 3 were arranged in the width direction on one end 1a side and the other end 1a side of one upper flange 11.

[0038] [Table 2]

[0039] Table 3 shows the ratio of initial stiffness and whether or not neck breakage occurred for specimens No. 1 to No. 8. Table 4 shows the ratio of initial stiffness and whether or not neck breakage occurred for specimens No. 9 to No. 16. The ratio of initial stiffness for specimens No. 1 to No. 8 is based on specimens with an embossed section length L3 of 120 mm. Specifically, the ratio of initial stiffness for No. 1 to No. 4 is obtained by dividing the initial stiffness of No. 1 to No. 4 by the initial stiffness of No. 1. The ratio of initial stiffness for No. 5 to No. 8 is obtained by dividing the initial stiffness of No. 5 to No. 8 by the initial stiffness of No. 5. The ratio of initial stiffness for specimens No. 9 to No. 16 is based on specimens with an embossed section 3 height of 0 mm (no embossing). That is, the ratio of initial stiffness for No. 9 to No. 12 is the value obtained by dividing the initial stiffness of No. 9 to No. 12 by the initial stiffness of No. 12. The ratio of initial stiffness for No. 13 to No. 16 is the value obtained by dividing the initial stiffness of No. 13 to No. 16 by the initial stiffness of No. 16.

[0040] The embossing ratio Z1 shown in Table 3 is the length P from the end 1a of the deck plate 1 to the end 3b of the embossed portion 3 / the length L2 of the end closing portion 2 × 100. The overlap ratio Z2 of the inclined portion of the end closing section 2 shown in Table 3 is the length Q from the end 21a of the inclined portion 21 to the end 3b of the embossed portion 3 / the length L21 of the inclined portion 21 of the end closing section 2 × 100.

[0041] [Table 3]

[0042] [Table 4]

[0043] As shown in Table 3, neck breakage occurred in specimens No. 1 and No. 5. Neck breakage did not occur in specimens No. 2 to No. 4 and No. 6 to No. 8.

[0044] As shown in Table 3, the initial stiffness of specimens No. 2 to No. 4 was greater than that of specimen No. 1. The initial stiffness of specimens No. 6 to No. 8 was greater than that of specimen No. 5.

[0045] As shown in Table 4, neck breakage occurred in specimens No. 12 and No. 16. Neck breakage did not occur in specimens No. 9 to No. 11 and No. 13 to No. 15.

[0046] As shown in Table 4, the initial stiffness of specimens No. 9 to No. 11 was greater than that of specimen No. 12. The initial stiffness of specimens No. 13 to No. 15 was greater than that of specimen No. 16.

[0047] From the above, it was confirmed that having the embossed portion 3 on the upper flange 11 improves the initial rigidity compared to the case without the embossed portion 3. As a result, the neck-bending resistance of the end-close portion 2 is improved, and neck-bending of the end-close portion 2 can be suppressed.

[0048] When the embossing ratio Z1 was 66.1% or higher (when the overlap ratio Z2 of the inclined section was 53.3%), no neck breakage occurred in the deck plate. This suggests that when the embossing ratio Z1 is 66.1% or higher, the initial rigidity is further improved, the neck breakage resistance of the end closing section 2 exceeds that of the deck plate 1, and neck breakage at the end closing section 2 can be suppressed more reliably. [Explanation of Symbols]

[0049] 1: Deck Plate 1a: End 11: Upper flange 11a:Protrusion 12: Lower flange 12a: Convex stripe 13: Web 13a: Stepped section 14: Engaging part 15: Engaging part 2: End closing section 21: Inclined part 21a: End 21b: End 22: Flat part 3: Embossed area 3a:Starting end 3b: Termination H: Height P: distance Z1: Embossing ratio Z2: Overlap ratio of the inclined section

Claims

1. A deck plate having an upper flange and a lower flange, and having an end closed portion formed by crushing the end in the longitudinal direction from the lower flange side, The upper flange has an embossed portion that protrudes upward at a position spaced apart in the width direction from the end closing portion. A deck plate featuring the following characteristics.

2. When P is the length from the end of the deck plate in the longitudinal direction to the end of the embossed portion, and L2 is the length of the end closing portion in the longitudinal direction of the deck plate, The condition P / L² × 100 ≥ 66.1 must be satisfied. The deck plate according to claim 1, characterized by the following:

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