JP2001317148A - Support structure for floor slab - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a support structure for a floor slab capable of realizing the safe and efficient construction work and demolition work at a low cost while maintaining the conventional effect for reducing the cross section of buried beams. SOLUTION: This support structure for the floor slab comprises the buried beams 11 supporting the floor slab (a second-layer floor slab 4a) including a floor permanent form (deck plate D) and placed unhardened concrete C, upper beams (first upper beams 12 and second upper beams 13) supporting the floor permanent form (deck plate D) on the upper layer, and hanging support members (first hanging support members 14 and second hanging support members 15) hanging and supporting the buried beams 11 from the upper beams (first upper beams 12 and second upper beams 13).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for manufacturing a floor cast form and a concrete before hardening between a time when concrete is cast on the form and the time when the concrete hardens to obtain a desired rigidity. The present invention relates to a support structure for a floor slab used for resisting internal stress generated in a floor slab containing the same.

[0002]

2. Description of the Related Art As a conventional structure for supporting a floor slab of this kind, a cast-off beam for supporting a floor slab containing concrete before being hardened and a cast-on-bed formwork on a specific floor, and Also, there is a structure that is configured to stand on an existing floor slab on the lower floor and to support the casting beam.

According to such a support structure for a floor slab, a portion of the load of the floor slab including the floor dumping formwork and the uncured concrete poured into the form can be borne by the support pillars. Compared to the case where the whole is borne by the cast beam,
There is an advantage that the cast beam can be reduced in cross section.

[0004]

However, in such a floor slab support structure, in order to obtain a stable support state, the upper end of the support column and the joint of the casting beam, the lower end of the support column, and the existing floor are required. Since it is necessary to strengthen the joints of the slab, there is a problem that the construction work and the dismantling work are extremely dangerous and complicated work including the construction and dismantling of these joints.

Further, since the support column is a column, the cross section is determined in consideration of buckling. As a result, the cross section of the actually used support column becomes large, which leads to an increase in cost. There are also problems.

Accordingly, an object of the present invention is to provide a floor slab support structure capable of realizing safe and efficient construction work and demolition work at a low cost while maintaining the conventional effect of reducing the cross section of a cast-in beam. Is to provide.

[0007]

That is, a floor slab support structure according to the present invention comprises a floor dumping formwork and a casting beam for supporting a floor slab containing concrete before being hardened which has been cast into the form. It is characterized by comprising an upper layer beam supporting a floor dumping formwork related to an upper layer, and a suspension support member for suspending and supporting the placing beam by the upper layer beam.

Therefore, according to the present invention, it is possible to avoid a very dangerous and complicated operation which is unavoidable in order to strengthen the joint between the support column and the cast-in beam in the conventional support structure using the support column. be able to. Therefore, safe and efficient construction work and dismantling work can be realized at low cost, and the conventional effect of reducing the cross section of the casting beam can be maintained.

[0009] In such technical means, the cast beam and the upper layer beam may be used before or after concrete is cast.
It does not matter what the configuration and the material are, as long as they serve to support the flooring formwork.

For example, any of a single beam, an assembled beam, a composite beam and the like may be used. In addition to steel, materials such as reinforced concrete (including prestressed concrete) and wood can be used.

[0011] The structure and material of the suspension support member are not limited as long as the suspension beam is suspended by the upper beam.

For example, a string-like member such as a wire or a rod-like member such as a reinforcing bar can be used. In addition, a single member or a composite member may be used. Further, in addition to steel (including a PC tendon), a material such as a new material such as Kevlar fiber can be used.

However, from the viewpoint of facilitating the construction by facilitating the adjustment of the suspension length, the suspension support member has a suspension length adjusting means for adjusting the suspension length. Is preferred.

Here, the suspension length adjusting means includes, for example, a turnbuckle or the like mounted in the middle of a rod-shaped member as a suspension support member.

[0015] Incidentally, the floor cast form referred to in the present invention is a formwork used for constructing a floor with cast-in-place concrete.
It is the material that remains as part of the structure without being removed after concrete is cast unsupported.

Here, the discarded formwork includes, for example, a deck plate, a flat deck, a half PC version, and the like.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings. FIG. 1 is a side view showing a schematic configuration of a floor slab support structure according to an embodiment of the present invention.

In the present embodiment, the support structure 1 for the second-layer floor slab is, as shown in the figure, erected between steel columns 3 vertically erected on the foundation structure 2. Out of a plurality of floor slabs, a deck plate D serving as a discarded formwork and concrete C to be cast before curing
And serves to support the second-layer floor slab 4a including

Specifically, as shown in FIG. 1, the support structure 1 includes a casting beam 11 erected in a horizontal direction at a portion related to the second floor slab 4a and a third floor slab. 4b, a first upper beam 12 laid horizontally in a portion related to the fourth floor slab 4c, a second upper beam 13 laid horizontally in a portion related to the fourth floor slab 4c, a casting beam 11 and a first upper layer The first suspension support member 14 is provided between the beams 12, and the second suspension support member 15 is provided between the casting beam 11 and the second upper beam 13.

As shown in FIG. 2, among the constituent elements of the support structure 1, the casting beam 11 is a second-layer floor slab including a deck plate D and concrete C to be cast thereon before hardening. 4a.

That is, between the time when the concrete C is cast on the deck plate D of the second layer and the time when the concrete C hardens and the desired rigidity is obtained, the cast beam 11 is formed.
Will bear the load of the second floor slab 4a.

However, after the second layer of concrete C is hardened and the desired rigidity is obtained, the load of the second layer of floor slab 4a is changed to the second layer of floor slab 4a after hardening of concrete C. It is borne by its own rigidity, and is no longer borne by the casting beam 11.

That is, after the second-layer concrete C is hardened, the cast-in beam 11 does not play a role of supporting the second-layer floor slab 4a and becomes unnecessary, so that it can be removed. .

As shown in FIG. 1, the first upper beam 12 is a third-layer deck plate D which is higher than the second layer.
Not only plays the role of supporting the deck plate D
And a role of suspending and supporting the casting beam 11 in a state of supporting the second-layer floor slab 4a including the uncured concrete C to be cast via the first suspension support member 14. Fulfill.

That is, from the time when the concrete C is cast on the second deck plate D to the time when the concrete C hardens to obtain the desired rigidity, the first upper beam 1
2 bears not only the load of the third-layer deck plate D but also the load of the second-layer floor slab 4a via the placing beam 11 and the first suspension support member 14. .

However, after the concrete C has hardened and the desired rigidity has been obtained, the load on the second floor slab 4a after the hardening of the concrete C is increased by the rigidity of the second floor slab 4a itself. , And is no longer borne by the first upper beam 12.

After the construction of the second floor slab 4a is completed, a support structure (not shown) for the third floor slab is newly constructed.
And the third-layer floor slab 4b including the unhardened concrete C to be cast thereon is supported. In the third-layer floor slab support structure, the first upper beam 12 is , Not as upper beams, but as cast beams.

Further, as shown in the figure, the second upper layer beam 13 has a deck plate D of a fourth layer which is higher than the second layer.
Not only plays the role of supporting the deck plate D
In addition, the casting beam 11 supporting the second-layer floor slab 4a containing the uncured concrete C to be cast is supported by the first suspension support member 14, the first upper beam 12, and the second suspension. It also plays the role of being suspended and supported via the support member 15.

That is, during the period from when the concrete C is cast on the deck plate D of the second layer to when the concrete C hardens and the desired rigidity is obtained, the second upper beam 1
3 not only bears the load of the fourth-layer deck plate D but also bears the load of the second-layer floor slab 4a.
The load is borne via the first suspension support member 14, the first upper beam 12, and the second suspension support member 15.

However, after the concrete C has hardened and the desired rigidity is obtained, the load on the second floor slab 4a after the hardening of the concrete C is increased by the rigidity of the second floor slab 4a itself. And the second upper beam 13 no longer bears.

On the other hand, the first suspension support member 14 plays a role of suspending and supporting the casting beam 11 by the first upper beam 12 as shown in FIG.

Specifically, as shown in FIG. 2, the first suspension support member 14 is threadedly engaged with a steel bar 14a having a thread formed at an upper end and a lower end, and an upper end of the steel bar 14a. The upper end of the steel bar 14a is fixed to the first upper beam 12 and screwed to the lower end of the steel bar 14a.
Nut 14b for fixing the lower end of 4a, and turnbuckle 1 as suspension length adjusting means mounted in the middle of steel bar 14a
4c.

The reason that the turnbuckle 14c is mounted in the middle of the steel bar 14a is that the adjustment of the suspension length is originally facilitated to facilitate the construction. However, the use of the turnbuckle 14c in the removal operation of the first suspension support member 14 facilitates the removal operation, and also has an economic advantage that the first suspension support member 14 can be diverted. can get.

As shown in FIG. 1, the second suspension support member 15 suspends the casting beam 11 via the first upper layer beam 12 and the first suspension support member 14 by the second upper layer beam 13. Play a supporting role.

As shown in FIG. 2, the second suspension support member 15, like the first suspension support member 14, also includes a steel bar 15a, a nut 15b, and a turnbuckle (not shown).

Next, the operation of the second-layer floor slab support structure 1 according to the present embodiment will be described with reference to FIGS. (A) Construction of the support structure 1, (b) Casting of concrete C, (c) Removal of the first suspension support member 14, (d)
The steps are separately described for placing the additional concrete C.

(A) Construction of Support Structure 1 Before the concrete C is cast on the second floor slab 4a, the support structure 1 of the second floor slab is constructed.

First, between the steel columns 3, the cast beam 1
1, the first upper beam 12 and the second upper beam 13 are erected in the horizontal direction.

Next, between the casting beam 11 and the first upper beam 12, the first suspension support member 14 is installed vertically, and between the first upper beam 12 and the second upper beam 13. The second suspension support member 15 is installed in the vertical direction.

Subsequently, the load borne by each suspension support member can be applied between the time when the concrete C is cast on the deck plate D of the second layer and the time when the concrete C hardens and the desired rigidity is obtained. Adjustment of the suspension length of the first suspension support member 14 and the second suspension support member 15 is performed in order to make them as uniform as possible.

At this time, by using the turnbuckle 14c, the operation of adjusting the suspension length of the first suspension support member 14 and the second suspension support member 15 can be considerably facilitated.

Then, among the constituent members of the support structure 1 for the constructed second-layer floor slab, the adjacent casting beams 11
In between, the deck plate D is erected in the horizontal direction.

(B) Casting of concrete C Next, concrete C is cast on the deck plate D erected between the casting beams 11 adjacent to each other.

Then, from the viewpoint of facilitating the work of removing the first suspension support member 14 after the concrete C is hardened, the box related to the turnbuckle 14c is unboxed.

At this time, the support structure 1 for the second floor slab
Is a second-layer floor slab 4a including the deck plate D and the uncured concrete C cast thereon before the concrete C hardens to obtain the desired rigidity.
Will be supported. That is, the support structure 1 for the second-layer floor slab can bear a part of the load of the second-layer floor slab 4a including the deck plate D and the uncured concrete C cast thereon. In comparison with the case where the entire load is borne by the casting beam 11, the cross section of the casting beam 11 can be reduced.

(C) Removal of the first suspension support member 14 After the concrete C has hardened to obtain the desired rigidity, the turnbuckle 14c is removed first, and then the lower end portion of the steel bar 14a. Most parts except for will be removed.

At this time, the removal of the first suspension support member 14 is considerably facilitated by utilizing the boxed portion related to the turnbuckle 14c.

The removed turnbuckle 14c, most of the steel bar 14a, and the nut 14b are diverted in a support structure (not shown) for the floor slab as the upper layer.

(D) Casting of additional concrete C Finally, concrete C is additionally poured into the box-cut portion of the turnbuckle 14c, and when the concrete C hardens, the second-layer floor slab 4a Will be completed.

Therefore, according to the support structure 1 for the floor slab of the second layer according to the present embodiment, in the support structure using the conventional support columns, the joints between the support columns and the cast beams 11 are strengthened. Therefore, it is possible to avoid extremely dangerous and complicated work which is inevitable.

As a result, safe and efficient construction work and dismantling work can be realized at low cost while maintaining the conventional effect of reducing the cross section of the casting beam 11.

Further, according to the present embodiment, before the second layer concrete C is hardened, it can be used as an upper beam in the support structure 1 of the second floor slab.
After the concrete of the layer C is hardened, it can be used as a cast-in beam in the support structure (not shown) for the floor slab in the third layer. Since the labor for erection of a casting beam exclusively for the support structure (not shown) of the floor slab can be omitted, work efficiency can be improved.

If not only the removed first suspension support member 14 but also the cast-in beams 11 and the upper beams are to be diverted to the floor slab support structure (not shown) relating to the upper layer, it is even more effective. Will be used effectively.

[0054]

According to the support structure for a cast-in-pile formwork of concrete casting according to the present invention, since it is constructed as described above, the conventional effect of reducing the cross section of the cast-in beam can be maintained while maintaining safety. Thus, efficient construction work and dismantling work can be realized at low cost.

[Brief description of the drawings]

FIG. 1 is a side view showing a schematic configuration of a floor slab support structure according to an embodiment of the present invention.

FIG. 2 is a side view showing a detailed configuration of a floor slab support structure according to one embodiment of the present invention.

FIG. 3 is a side view illustrating the operation of the floor slab support structure according to one embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Support structure of 2nd floor slab 2 ... Foundation structure 3 ... Steel column 4 ... Floor slab 4a ... 2nd floor slab 4b ... 3rd floor slab 4c ... 4th floor slab 11 ... Striking Mounting beam 12 ... First upper beam 13 ... Second upper beam 14 ... First suspension support member 14a ... Bar steel 14b ... Nut 14c ... Turnbuckle 15 ... Second suspension support member 15a ... Bar steel 15b ... Nut D ... Deck plate (Floor form) C… Concrete

Claims (1)

[Claims] 1. A cast-in-place beam and a cast-in beam for supporting a floor slab containing concrete before being hardened, which is cast in the cast-in-form form, an upper beam supporting a cast-in-place formwork related to a higher layer, A supporting structure for a floor slab, comprising: a suspension support member for suspending and supporting the casting beam by an upper layer beam.