JP4228300B2 - Precast concrete slab - Google Patents

Description

  The present invention relates to a precast concrete slab constituting a floor structure of a building.

In steel-frame buildings, in consideration of improving workability at the time of construction, there has been almost no design taking into account dismantling and reusability. From the viewpoint of waste and life cycle CO ₂ , in order to make a steel structure that is easy to assemble and dismantle and can be reused, the floor structure is a precast concrete slab (hereinafter referred to as PCa slab), and the PCa slab is It is effective to bolt the steel beam. For example, a bolt hole for bolting is provided on the periphery of a rectangular PCa slab, and the PCa slab is bolted to the steel beam through the bolt hole. However, with this configuration, the rigid floor assumption, which is a major premise in structural design, is no longer valid.

  Therefore, conventionally, there is a structure in which a rectangular frame-like floor frame is configured, a brace material is attached across diagonal corners in a rectangular space in the floor frame, and a concrete floor board is attached to the upper surface of the floor frame. That is, a brace is installed under a concrete slab to increase the rigidity in the floor (for example, see Patent Document 1).

Japanese Patent Laid-Open No. 5-112996

  However, in the conventional configuration, since the installation of the floor frame and the brace is a high place work, there is a problem that the workability is poor and the material cost is high, so that the cost is increased.

  In view of the above circumstances, an object of the present invention is to provide a precast concrete slab capable of reducing cost while having sufficient rigidity.

In order to achieve the above-mentioned object, a precast concrete slab according to claim 1 of the present invention includes a bowl-shaped horizontal brace embedded in a concrete floor board, and is fixed to an end of the horizontal brace. A fixing portion that is exposed to an outer edge of the floor board and is fixed to the building beam material, and the fixing portion is fixed to an end portion of the horizontal brace via a fixing bar. To do.

A precast concrete slab according to a second aspect of the present invention is the precast concrete slab according to the first aspect , wherein the fixing portion is a pipe that opens in the vertical direction in such a manner that the fixing portion is inserted from above into a fixing bolt erected on the building beam material. It consists of a shape member, It fixes to the said building beam material via the said fixing bolt, It is characterized by the above-mentioned.

Precast concrete slab according to claim 3 of the present invention, in the claim 1, wherein the fixing unit includes a pipe-like member that opens toward the fixing bolts fixed to the building beam members in the vertical direction in a manner to be loosely inserted The mortar material is filled inside the loose bolt and fixed to the building beam material.

A precast concrete slab according to a fourth aspect of the present invention is the precast concrete slab according to any one of the first to third aspects, wherein the reinforcing bars embedded in the concrete floor board in the form along the plate surface of the concrete floor board are replaced with the horizontal braces. It is characterized by being arranged vertically.

  In the precast concrete slab according to the present invention, horizontal braces are embedded in the concrete floor slabs, and fixed portions that are exposed to the outer edges of the concrete floor slabs and fixed to the building beam material with respect to both ends of the horizontal braces. It is fixed. Thereby, by joining a concrete floor board to a building beam material via a fixed part, a horizontal brace can be joined to a building beam material together with the concrete floor board. As a result, sufficient rigidity as a concrete floor board can be obtained. Moreover, since the work at a high place becomes easy compared with the case where a horizontal brace is installed separately from a concrete floor board, workability | operativity improves and it can reduce cost.

  Sufficient rigidity can be obtained because the horizontal braces are provided in such a manner that both end portions to which the fixing portion is fixed are communicated with each other within the thickness of the concrete floor plate with the outer edge of the concrete floor plate being directed to the outside edge.

  The horizontal brace has a fixed part fixed to one end facing the outer edge of the concrete floor slab, and a bent part is provided at the other end stopped inside the concrete floor slab, so that the bent part engages with the concrete floor slab. And sufficient rigidity can be obtained. In particular, this horizontal brace can reduce the material cost because the length can be shortened compared to the configuration in which both ends are X-shaped toward the outer edge of the concrete floor board.

  By fixing the fixing part to the end of the horizontal brace through the fixing bar, the fixing bar can absorb the dimensional error between the horizontal brace and the fixing part, so that the workability is improved and the cost is reduced. be able to.

  The fixing part consists of a pipe-like member that opens in the vertical direction in a manner that it is inserted from above into a fixing bolt standing on the building beam material, and is fixed to the building beam material via the fixing bolt. Thereby, the inner surface yield strength of the joint portion on the concrete floor board side can be improved.

  The fixed part consists of a pipe-shaped member that opens in the up-down direction in a manner of loosely inserting a fixing bolt fixed to the building beam material, and the interior fixed to the building beam material is filled with mortar material to make the building beam material On the other hand, the concrete floor board can be joined by absorbing the error of the mounting position of the fixing bolt fixed to the building beam material.

  By arranging the reinforcing bars embedded in the concrete floor plate along the plate surface of the concrete floor plate above and below the horizontal brace, the state of engagement of the horizontal brace with the concrete floor plate is improved. Yield strength can be improved and cracking of the concrete floor board can be prevented.

  Exemplary embodiments of a precast concrete slab according to the present invention will be described below in detail with reference to the accompanying drawings. Note that the present invention is not limited to the embodiments.

  1 is a plan view showing a precast concrete slab in Example 1 of the present invention, FIG. 2 is a side sectional view of the precast concrete slab in Example 1, and FIG. 3 is a partially enlarged sectional view of the precast concrete slab in Example 1. 4 is an enlarged cross-sectional view showing a joined state of the precast concrete slab in the first embodiment, and FIG. 5 is an enlarged plan view showing a joined state of the precast concrete slab in the first embodiment.

  As shown in FIG. 1, a precast concrete slab (hereinafter referred to as PCa slab) in Example 1 has a concrete floor board 1 as a base, a horizontal brace 2 and a reinforcing bar 3 are embedded in the concrete floor board 1, and concrete is also provided. The fixed portion 4 is exposed on the outer edge of the floor board 1.

  The concrete floor board 1 is manufactured in advance with concrete, and in the present embodiment, the concrete floor board 1 is formed in a rectangular shape and forms a plate having a predetermined thickness.

  The horizontal brace 2 is formed in a bowl shape with round steel or deformed reinforcing bars, and is embedded in the thickness of the concrete floor board 1 so as to face the diagonal of the concrete floor board 1. That is, the horizontal brace 2 is provided in an X shape within the thickness of the concrete floor board 1 in plan view.

  As shown in FIG. 2, the reinforcing bar material 3 is formed of a welded wire mesh, a deformed reinforcing bar, or the like, and is buried in communication with the thickness of the concrete floor board 1. The reinforcing bars 3 are arranged above and below the horizontal braces 2 in a manner along the plate surface of the concrete floor board 1. Thereby, the engagement state of the horizontal brace 2 to the concrete floor board 1 is improved, the strength of the concrete floor board 1 is improved, and the crack of the concrete floor board 1 is prevented.

  The fixing portion 4 is provided so as to be exposed at each corner portion which is the outer edge of the concrete floor board 1. The fixing portion 4 is fixed to both end portions of the horizontal brace 2 facing the corner portion of the concrete floor board 1. As shown in FIG. 3, the fixing portion 4 is formed in a round pipe shape in which the openings 4 a and 4 b are directed in the vertical direction in such a manner that a fixing bolt 11 a described later is inserted, and the upper end thereof is the lower surface of the end plate 5. It is attached by welding. The end plate 5 is provided with a hole 5 a communicating with the opening 4 a above the fixed portion 4. The end plate 5 to which the fixing portion 4 is attached is fixed to both ends of the horizontal brace 2 by welding. In addition, the fixed portion 4 has an upper opening 4 a exposed to the outer edge (corner portion) of the concrete floor board 1 along with the hole 5 a of the end plate 5 by a notch 1 a provided on the upper surface of the concrete floor board 1. Further, the lower end of the fixed portion 4 is flush with the lower surface of the concrete floor board 1 so that the lower opening 4 b is exposed from the lower surface of the concrete floor board 1.

  As shown in FIGS. 4 and 5, in order to join the above-described PCa slab to the steel beam 10 as a building beam material, a fixing bolt 11 a is welded to the upper flange 10 a of the steel beam 10. Then, the lower opening 4b of the fixing portion 4 is inserted into the upper end of the fixing bolt 11a from above. Then, the nut 11 b is tightened to the upper end of the fixing bolt 11 a extending from the opening 4 a above the fixing portion 4 and the hole 5 a of the end plate 5. Thereby, the concrete floor board 1 is joined to the steel beam 10.

  Thus, the PCa slab in Example 1 has the horizontal brace 2 embedded in the concrete floor board 1, and the fixing portion 4 that is exposed to the outer edge of the concrete floor board 1 and fixed to the steel beam 10. It is fixed to both ends of the horizontal brace 2. Thereby, it is possible to join the horizontal brace 2 to the steel beam 10 together with the concrete floor plate 1 by installing the concrete floor plate 1 to the steel beam 10 through the fixing portion 4. As a result, sufficient rigidity as the concrete floor board 1 can be obtained. Moreover, since the work in a high place becomes easy compared with the case where a horizontal brace is installed separately from the concrete floor board 1, workability improves and cost can be reduced. Furthermore, since the horizontal brace 2 is provided in such a manner that both end portions to which the fixing portion 4 is fixed are communicated with each other within the thickness of the concrete floor board 1 toward the outer edge of the concrete floor board 1, sufficient rigidity can be obtained. Furthermore, since the fixing portion 4 inserted and fixed to the fixing bolt 11a fixed to the steel beam 10 is formed in a pipe shape, the inner surface strength of the joint portion on the concrete floor board 1 side can be improved.

  6 is a plan view showing a precast concrete slab in Example 2 of the present invention, FIG. 7 is a side sectional view of the precast concrete slab in Example 2, and FIG. 8 is a partially enlarged sectional view of the precast concrete slab in Example 2. 9 is an enlarged cross-sectional view showing the joined state of the precast concrete slab in Example 2, and FIG. 10 is an enlarged plan view showing the joined state of the precast concrete slab in Example 2.

  In the second embodiment described below, the same parts as those in the first embodiment are denoted by the same reference numerals.

  As shown in FIG. 6, the precast concrete slab (hereinafter referred to as PCa slab) in Example 2 has a concrete floor board 1 as a base, a horizontal brace 2 and a reinforcing bar 3 embedded in the concrete floor board 1, and concrete. The fixed portion 4 is exposed on the outer edge of the floor board 1.

  The concrete floor board 1 is manufactured in advance with concrete, and in the present embodiment, the concrete floor board 1 is formed in a rectangular shape and forms a plate having a predetermined thickness.

  The horizontal brace 2 is formed in a bowl shape with round steel or deformed reinforcing bars, and is embedded in the thickness of the concrete floor board 1 so as to face the diagonal of the concrete floor board 1. That is, the horizontal brace 2 is provided in an X shape within the thickness of the concrete floor board 1 in plan view.

  As shown in FIG. 7, the reinforcing bar material 3 is made of a welded wire mesh, a deformed reinforcing bar, or the like, and is embedded in the thickness of the concrete floor board 1. The reinforcing bars 3 are arranged above and below the horizontal braces 2 in a manner along the plate surface of the concrete floor board 1. Thereby, the engagement state of the horizontal brace 2 to the concrete floor board 1 is improved, the strength of the concrete floor board 1 is improved, and the crack of the concrete floor board 1 is prevented.

  The fixing portion 41 is provided so as to be exposed at each corner portion which is the outer edge of the concrete floor board 1. The fixing portion 41 is fixed to both ends of the horizontal brace 2 facing the corner portion of the concrete floor board 1. As shown in FIG. 8, the fixing portion 41 is formed in a square pipe shape (in this embodiment, a rectangular pipe shape) with the openings 41a and 41b facing in the vertical direction in such a manner that a fixing bolt 11a described later is loosely inserted. The outer part is attached to the edge of the end plate 5 by welding. The end plate 5 to which the fixing portion 41 is attached is fixed to both end portions of the horizontal brace 2 by welding. The fixed portion 4 has a vertical length substantially the same as the thickness of the concrete floor board 1, and the upper and lower openings 4 a and 4 b are exposed at the outer edge (corner) of the concrete floor board 1. Furthermore, the fixed portion 4 forms a corner portion of the concrete floor board 1 with a rectangular pipe shape.

  9 and 10, in order to join the above-described PCa slab to the steel beam 10 as a building beam material, the concrete floor board 1 is placed on the upper flange 10 a of the steel beam 10, and the pipe of the fixing portion 41 is placed. Inside, the fixing bolt 11a is fastened and fixed to the steel beam 10 with a nut 11b. That is, the fixing portion 41 is loosely inserted into the fixing bolt 11a. Then, the mortar material 12 is filled in the pipe of the fixed portion 41. Thereby, the concrete floor board 1 is joined to the steel beam 10.

  Thus, in the PCa slab in Example 2, the horizontal brace 2 is embedded inside the concrete floor board 1, and the fixing portion 41 that is exposed to the outer edge of the concrete floor board 1 and fixed to the steel beam 10 is provided. It is fixed to both ends of the horizontal brace 2. Accordingly, the horizontal brace 2 can be joined to the steel beam 10 together with the concrete floor plate 1 by installing the concrete floor plate 1 to the steel beam 10 through the fixing portion 41. As a result, sufficient rigidity as the concrete floor board 1 can be obtained. Moreover, since the work in a high place becomes easy compared with the case where the horizontal brace 2 is installed separately from the concrete floor board 1, workability improves and it can reduce cost. Furthermore, since the horizontal brace 2 is provided in such a manner that both ends to which the fixing portion 41 is fixed are communicated with each other within the thickness of the concrete floor board 1 toward the outer edge of the concrete floor board 1, sufficient rigidity can be obtained. Furthermore, since the fixing portion 41 is loosely inserted into the fixing bolt 11a fixed to the steel beam 10 and the mortar material 12 is filled in the pipe of the fixing portion 41, the mounting position of the fixing bolt 11a fixed to the steel beam 10 The concrete floor board 1 can be joined by absorbing the above error.

  Hereinafter, another embodiment of the horizontal brace will be described. FIG. 11 is a plan view showing a precast concrete slab having another form of horizontal brace, and FIG. 12 is a side sectional view of the precast concrete slab having another form of horizontal brace.

  11 and 12, the fixing portion 41 in the second embodiment described above is employed, but the fixing portion 4 in the first embodiment may be employed.

  As shown in FIGS. 11 and 12, the horizontal brace 21 is formed in a bowl shape with round steel or deformed reinforcing bars, and the fixed portion 41 (4) is provided at one end 21 a facing the outer edge of the concrete floor board 1. A bent portion 13 is provided at the other end portion 21 b fixed and fixed inside the concrete floor board 1. As shown in FIG. 11, the bent portion 13 is curved and formed in a substantially U shape. The other bent portion 13 may be substantially L-shaped or substantially V-shaped, and may have any shape as long as it has other bends.

  The PCa slab having such a horizontal brace 21 can obtain the same rigidity as the first and second embodiments because the bent portion 13 engages with the concrete floor board 1. In particular, according to the horizontal brace 21, the length can be shortened as compared with the horizontal brace 2 whose both ends are X-shaped toward the outer edge of the concrete floor board 1, so that the material cost can be reduced.

  Hereinafter, still another form of the horizontal brace will be described. FIG. 13 is a plan view showing a precast concrete slab having still another form of horizontal brace, and FIG. 14 is a side sectional view of the precast concrete slab having still another form of horizontal brace.

  In FIG. 13 and FIG. 14, the fixing portion 41 in the second embodiment described above is employed, but the fixing portion 4 in the first embodiment may be employed.

  As shown in FIG. 13 and FIG. 14, the horizontal brace 22 is formed in a bowl shape with round steel or deformed reinforcing bar, and communicates with the concrete floor board 1 within the thickness thereof toward the diagonal of the concrete floor board 1. Buried. That is, the horizontal brace 22 is provided in an X shape within the thickness of the concrete floor board 1 in plan view. Fixing portions 41 (4) are fixed to both ends of the horizontal brace 22 via fixing bars 14. The fixing bar 14 is a reinforcing bar bent in a substantially U shape, and is lap welded along the length direction of the horizontal brace 22. Further, the fixing muscle 14 has a substantially U-shaped bent portion welded to the fixing portion 41 (4). The fixing muscle 14 may be bent in a substantially L shape other than a substantially U shape, and the bent portion may be welded to the fixing portion 41 (4).

  The PCa slab having such a horizontal brace 22 can obtain the same rigidity as in the first and second embodiments. In particular, according to the horizontal brace 22, since the dimensional error between the horizontal brace 22 and the fixing portion 41 (4) can be absorbed by the fixing bars 14, the workability is improved and the cost can be reduced.

  As described above, the precast concrete slab according to the present invention is suitable for reducing cost while having sufficient rigidity.

It is a top view which shows the precast concrete slab in Example 1 of this invention. It is a sectional side view of the precast concrete slab in Example 1. It is a partial expanded sectional view of the precast concrete slab in Example 1. FIG. It is an expanded sectional view which shows the joining state of the precast concrete slab in Example 1. FIG. It is an enlarged plan view which shows the joining state of the precast concrete slab in Example 1. FIG. It is a top view which shows the precast concrete slab in Example 2 of this invention. It is a sectional side view of the precast concrete slab in Example 2. It is a partial expanded sectional view of the precast concrete slab in Example 2. FIG. It is an expanded sectional view which shows the joining state of the precast concrete slab in Example 2. FIG. It is an enlarged plan view which shows the joining state of the precast concrete slab in Example 2. FIG. It is a top view which shows the precast concrete slab which has another form of a horizontal brace. FIG. 4 is a side cross-sectional view of a precast concrete slab having another form of horizontal brace. It is a top view which shows the precast concrete slab which has another form of a horizontal brace. FIG. 5 is a side cross-sectional view of a precast concrete slab having yet another form of horizontal braces.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Concrete floor board 1a Notch 2 Horizontal brace 21 Horizontal brace 21a One end part 21b Other end part 22 Horizontal brace 3 Reinforcement material 4 Fixing part 4a Upper opening 4b Lower opening 41 Fixing part 41a Upper opening 41b Lower opening 5 End part Plate 5a Hole 10 Steel beam 10a Upper flange 11a Fixing bolt 11b Nut 12 Mortar material 13 Bending part 14 Anchoring bar

Claims (4)

A bowl-shaped horizontal brace embedded in a concrete floor slab, and a fixed part fixed to an end of the horizontal brace and exposed to an outer edge of the concrete floor slab and fixed to a building beam. ,
The precast concrete slab , wherein the fixing portion is fixed to an end portion of the horizontal brace through a fixing bar. The fixing portion is composed of a pipe-like member that opens in the vertical direction in a manner of being inserted from above into a fixing bolt that is erected on the building beam material, and is attached to the building beam material via the fixing bolt. The precast concrete slab according to claim 1, which is fixed. The fixing portion is composed of a pipe-shaped member that opens in a vertical direction in a mode in which a fixing bolt fixed to the building beam material is loosely inserted, and is filled with a mortar material in the inside where the fixing bolt is loosely inserted. The precast concrete slab according to claim 1, wherein the precast concrete slab is fixed to the building beam material. The precast according to any one of claims 1 to 3 , wherein reinforcing bars embedded in the concrete floor board are arranged above and below the horizontal brace in a mode along the plate surface of the concrete floor board. Concrete slab.

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