JP2020059983A - Base floor structure and construction method of base floor - Google Patents

Abstract

To provide a base floor structure improving workability of constructing a base floor.SOLUTION: A base floor structure 10 comprises: a concrete filled steel tube column 50 filled with concrete in an inner part of a sub-structural column 52 formed with steel pipes placed in a base floor 12; a capital plate 150 connected on an outer peripheral surface 50A of the concrete filled steel tube column 50; a lib plate 160 connected on an upper surface 153 of the capital plate 150 and the outer peripheral surface 50A; and a flat slab 100 in which the rib plate 160 supported with the capital plate 150 is buried.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a basement floor structure and a method for constructing a basement floor.

  A reverse driving method is known in which the underground structure is excavated from the upper floor to the lower floor and the structure is sequentially repeated.

  Patent Document 1 discloses a technique relating to a joint structure between a flat slab and a concrete-filled steel tubular column in a reverse driving method.

  In this prior art, a ring plate is arranged on the outer peripheral surface of a concrete-filled steel pipe column corresponding to the main bar of the flat slab, and a plurality of steel rib plates radially arranged at predetermined intervals between the ring plates are arranged. . Also, by welding one end to the ring plate and arranging a plurality of column anchoring lines radially around the concrete-filled steel tubular column, at least one row of hoop lines that are fixed to the rib plate and surround the periphery of the concrete-filled steel tubular column. The main bar of the flat slab is reinforced. This eliminates the flat slab's capital part in the concrete-filled steel tube column.

Patent 3728653

  The technique of Patent Document 1 can eliminate the capital portion, but the arrangement of reinforcement around the concrete-filled steel tubular column in the flat slab becomes complicated. Therefore, there is room for improvement in improving workability.

  In view of the above facts, the present invention has an object to improve the workability of constructing a basement floor.

  A first aspect is provided on a basement floor, a true column made of steel pipe, a capital plate joined to the outer peripheral surface of the true column, and an upper surface of the capital plate and the outer peripheral surface. The basement floor structure includes a rib plate and a flat slab supported by the capital plate and having the rib plate embedded therein.

  In the first aspect, since the flat slab is supported by the capital plate joined to the outer peripheral surface of the true column made of steel pipe, the reinforcement of the periphery of the true column in the flat slab does not become complicated. Therefore, the workability of constructing the basement is improved.

  A second aspect, the flat slab has a receiving portion that is convex on the lower side extending in one direction, and the capital plate supports the receiving portion, the basement floor structure according to the first aspect. Is.

  In the second aspect, since the convex receiving portion that extends in one direction is provided on the lower side, it is possible to widen the interval in the extending direction of the concrete-filled steel tubular columns that support the flat slab.

  A third aspect is a reverse driving method of simultaneously constructing a ground floor and a basement floor, by excavating the ground, joining a capital plate to the outer peripheral surface of a true column made of steel pipe, and the outer peripheral surface and the capital plate. Construction of a basement floor including a step of joining a rib plate to the upper surface of the base plate and a step of constructing a flat slab constituting the basement floor by using the excavated surface of the ground and the capital plate as a formwork Is the way.

  In the third aspect, the frame construction of each floor of the underground floor after excavation is the joining of the capital plate and the rib plate to the concrete-filled steel tubular column (structured column) and the construction of the flat slab supported by the capital plate. , The manpower on the basement floor is reduced.

  Moreover, since the flat slab that constitutes the basement floor is constructed by using the excavated surface and the capital plate as a formwork, the excavated soil volume is reduced and the work efficiency is improved.

  Alternatively, a flat concrete slab may be constructed by placing a waste container on the excavated surface.

  Also, the rib plate is joined only to the upper surface of the capital plate, and the lower surface of the capital plate is a flat surface, so when joining the capital plate to the concrete-filled steel tubular column (structured column), the concrete-filled steel tubular column (structured column) The amount of excavation around can be reduced.

  A fourth aspect is to construct a rock mass form having at least one of a concave portion for forming a convex receiving portion on the lower side extending in one direction and a convex portion for forming an opening on the excavation surface. It is a method of constructing a basement floor of a third aspect, which comprises a step and a step of constructing the flat slab having at least one of the receiving portion and the opening portion by using the ground formwork.

  In the fourth aspect, by constructing a rock mass form having at least one of a concave portion for forming a receiving portion and a convex portion for forming an opening portion (temporary opening, equipment opening, etc.) on the excavation surface, At least one of the portion and the opening can be easily formed in the flat slab.

  According to the present invention, the workability of constructing a basement floor can be improved.

1 is a vertical sectional view of a basement floor to which a basement floor structure of one embodiment of the present invention is applied. It is sectional drawing which looked up at the cross section along the 2-2 line of FIG. It is an expanded sectional view which expanded the principal part of FIG. It is the perspective view which looked down the inside of the basement floor of FIG. 1 from diagonally above. It is sectional drawing of the state which formed the ground formwork on the excavation surface and constructed the flat slab. It is an expanded sectional view corresponding to Drawing 3 of other examples of an embodiment.

<Embodiment>
A basement floor structure and a basement floor construction method according to an embodiment of the present invention will be described. It should be noted that the two directions orthogonal to the horizontal direction are the X direction and the Y direction, which are indicated by arrows X and Y, respectively. Further, a vertical direction orthogonal to the X direction and the Y direction is defined as a Z direction, and is indicated by an arrow Z.

[Construction]
First, the basement floor constructed by the reverse driving method for constructing the ground floor and the basement floor at the same time will be described.

  As shown in FIGS. 1, 3 and 4, the basement floor 12 to which the basement floor structure 10 of the present embodiment is applied has a concrete-filled steel pipe column 50, a capital plate 150, a rib plate 160, and a flat slab 100. ing. Note that “1FL” in FIG. 1 indicates the level of the slab on the first floor.

  As shown in FIG. 1, the concrete-filled steel pipe column 50 has a structure in which concrete S (see FIG. 2) is filled inside the structure column 52 built in the concrete of the cast-in-place pile 20. As shown in FIG. 2, the concrete-filled steel tubular column 50 (structured column 52) of the present embodiment has a rectangular cross section orthogonal to the axial direction, but is not limited to this. For example, the cross section may be circular.

  As shown in FIGS. 1, 3 and 4, the flat slab 100 of the present embodiment is a reinforced concrete structure (see FIGS. 1 and 3) and is unidirectional (Y direction in the present embodiment, see FIG. 4). A one-way capital 120 is formed as an example of a receiving portion that is convex downward and extends. As shown in FIG. 4, the one-way capitals 120 are formed in parallel in parallel with each other at intervals in the X direction.

  As shown in FIGS. 1 and 3, slab-side main reinforcements 112 and slab-side distribution muscles 114 are arranged in a grid shape in a plan view at the upper and lower portions of the flat slab 100. In addition, at the lower part of the one-way capital 120, capital-side force distribution muscles 122 and capital-side main reinforcements 124 are arranged in a grid pattern in a plan view. It should be noted that both ends 122 </ b> A of the capital-side force distribution muscle 122 are curved obliquely upward, and the tip end portion thereof is positioned above the lower slab-side main muscle 112.

  As shown in FIGS. 1 to 4, the capital plate 150 is joined to the outer peripheral surface 50A of the concrete-filled steel pipe column 50 (structured column 52). The capital plate 150 of the present embodiment is composed of four divided plates 152.

  The rib plate 160 is joined to the upper surface 153 of each divided plate 152 of the capital plate 150 and the outer peripheral surface 50A of the concrete-filled steel tubular column 50 (structured column 52). The concrete-filled steel pipe column 50 (true column 52), the division plate 152, and the rib plate 160 are joined by welding.

  As shown in FIGS. 1, 3 and 4, in the present embodiment, the capital plate 150 supports the one-way capital 120 of the flat slab 100, and the rib plate 160 is embedded in the one-way capital 120.

  As shown in FIG. 4, a temporary opening 70 is formed as an example of the opening in the flat slab 100 of this embodiment in which the basement floor 12 is being constructed. The temporary opening 70 is filled and closed when the basement 12 is completed.

[Construction method]
Next, an example of a method for constructing a basement floor by the reverse construction method will be described with reference to FIG. Note that, in FIG. 5, the slab-side main reinforcement 112, the slab-side distribution muscle 114, the capital-side distribution muscle 122, and the capital-side main reinforcement 124 (see FIG. 3) are omitted.

  First, the cast-in-place pile 20 (see FIG. 1) is driven into the ground 30, and the true column 52 (see FIG. 1) is built in the pile head.

  Next, the ground 30 is excavated. A hole 38 for welding the capital plate 150 (divided plate 152) and the rib plate 160 is formed around the true column 52. The capital plate 150 (divided plate 152) is welded to the outer peripheral surface 50A of the true column 52, and the rib plate 160 is joined to the outer peripheral surface 50A and the upper surface 153 of the capital plate 150 (divided plate 152). Further, the concrete columns 52 are filled with concrete S (see FIG. 2) to obtain concrete-filled steel pipe columns 50.

  It is preferable to fill the concrete columns 52 with concrete S after welding the capital plate 150 (divided plate 152) and the rib plate 160 to the outer peripheral surface 50A of the true columns 52. After filling with, the capital plate 150 (divided plate 152) and the rib plate 160 may be welded to the outer peripheral surface 50A of the true column 52.

  Further, the ground 30 is excavated, and the ground form 36 having the groove-shaped concave portion 32 for forming the one-way capital 120 and the convex portion 34 for forming the temporary opening 70 is formed on the excavated surface 30A. .

  Then, the slab-side main reinforcement 112, the slab-side distribution reinforcement 114, the capital-side distribution reinforcement 122, and the capital-side main reinforcement 124 (see FIGS. 1 and 3) are arranged, and the ground form 36 and the capital plate 150 are formed into a form. Concrete is poured as described above to construct the flat slab 100 having the one-way capital 120 and the temporary opening 70.

  Although not shown, the flat slab 100 is actually constructed by placing a waste concrete on the excavation surface 30A.

  Then, the ground 30 is excavated from the temporary opening 70 to similarly construct the lower floor. As described above, the temporary opening 70 is closed by the time the basement 12 is completed.

[Action and effect]
Next, the operation and effect of this embodiment will be described.

  Since the flat slab 100, in the present embodiment, the one-way capital 120 is supported by the capital plate 150 joined to the outer peripheral surface 50A of the concrete-filled steel pipe column 50, the reinforcement of the periphery of the concrete-filled steel pipe column 50 in the flat slab 100 is complicated. do not become. Therefore, the workability of constructing the basement floor 12 is improved.

  Since the flat slab 100 of this embodiment has the one-way capital 120, the installation interval in the extending direction (Y direction) of the concrete-filled steel tubular column 50 supporting the flat slab 100 can be widened.

  In addition, since the frame construction of each floor of the basement floor 12 after excavation is the joining of the capital plate 150 and the rib plate 160 to the concrete-filled steel pipe column 50 (structure column 52) and the construction of the flat slab 100, the basement floor 12 work man-hours are reduced.

  Since the rib plate 160 is joined only to the upper surface 153 of the capital plate 150 and the lower surface of the capital plate 150 remains flat, the capital plate 150 is joined to the outer peripheral surface 50A of the concrete-filled steel pipe column 50 (structure column 52). In this case, the amount of excavation of the hole 38 around the concrete-filled steel pipe column 50 (true column 52) can be reduced as compared with the case where the plate is joined to the lower surface of the capital plate 150. Therefore, excavation work time can be reduced.

  In addition, since the flat slab 100 is constructed by using the excavated surface 30A and the capital plate 150 as a mold, the excavated soil amount is reduced and the work efficiency is improved.

  Further, by constructing a rock mass form 36 having a concave portion 32 for forming the one-way capital 120 and a convex portion 34 for forming the temporary opening 70 on the excavation surface 30A, the one-way capital 120 and the temporary opening 70 are formed. Can be easily formed on the flat slab 100.

  Further, since the flat slab 100 does not require a beam, the floor height can be reduced and the amount of excavated soil can be reduced. Further, the shallow excavation depth improves the construction speed of the basement floor 12.

<Other>
The present invention is not limited to the above embodiment.

  For example, in the above-described embodiment, the flat slab 100 having the one-way capital 120 as an example of the receiving unit is used, but the present invention is not limited to this. Unlike the flat slab 101 of the basement floor 13 to which the basement floor structure 11 of another example shown in FIG. 6 is applied, the one-way capital 120 (see FIG. 3) may not be provided. In this case, the recess 32 (see FIG. 5) is not formed in the natural formwork.

  Further, for example, although the temporary opening 70 is formed in the flat slab 100, an opening other than the temporary opening 70 may be formed. For example, an equipment opening through which a pipe or the like is passed may be formed.

  Further, for example, in the above-described embodiment, the pillar on the basement floor is the concrete-filled steel pipe pillar 50 in which the concrete S is filled in the interior of the structure pillar 52 made of a steel pipe, but the present invention is not limited to this. The true column 52 may not be filled with the concrete S.

  Further, for example, in the above-described embodiment, the basement floor structure of the present invention is applied to the basement floor constructed by the reverse driving method in which the ground floor and the basement floor are simultaneously constructed, but the present invention is not limited to this. The basement floor structure of the present invention can also be applied to a basement floor constructed by a sequential driving method of excavating and dropping a slab.

  Furthermore, the present invention can be implemented in various modes without departing from the spirit of the present invention.

10 Basement floor structure 11 Basement floor structure 12 Basement floor 13 Basement floor 30 Ground 30A Excavation surface 32 Recessed portion 34 Convex portion 36 Rock mass form 50A Outer peripheral surface 52 Structured column 70 Temporary opening (an example of opening)
100 flat slab 101 flat slab 120 one-way capital (an example of receiving part)
150 Capital plate 153 Upper surface 160 Rib plate

Claims (4)

With a true pillar made of steel pipes on the basement floor,
A capital plate joined to the outer peripheral surface of the structure column,
A rib plate joined to the upper surface of the capital plate and the outer peripheral surface,
A flat slab supported by the capital plate and in which the rib plate is embedded,
Basement structure with. The flat slab has a convex receiving portion on the lower side extending in one direction,
The capital plate supports the receiving portion,
The basement floor structure according to claim 1. In the reverse construction method that constructs the ground floor and the basement at the same time,
Excavating the ground, and joining a rib plate to the outer peripheral surface and the upper surface of the capital plate together with joining the capital plate to the outer peripheral surface of the true column made of steel pipe,
A step of constructing a flat slab that constitutes the basement floor by utilizing the excavated surface of the natural ground and the capital plate as a formwork forming the lower surface;
How to build a basement with. A step of constructing a rock mass formwork having at least one of a concave portion for forming a convex receiving portion on the lower side extending in one direction and a convex portion for forming an opening on the excavation surface,
A step of constructing the flat slab having at least one of the receiving portion and the opening portion using the natural formwork;
The method for constructing a basement floor according to claim 3, further comprising: