JP2020125630A - Building construction method - Google Patents

Abstract

To provide a building construction method capable of smoothly proceeding with excavation of the ground and construction of an underground structure in an inner area.SOLUTION: A building method comprises a step S1 of constructing a temporary wall 22 and constructing an under-ground piled column 23 in an outer peripheral area 20B, a step S2 of excavating a ground 2 of a central area 20A to a planned base level 24 while driving a ground anchor 25 from a wall surface of the temporary wall 22 toward the outer peripheral area 20B, a step S3 of constructing a preceding floor 17B in the outer peripheral area 20B and supporting it with the under-ground piled column 23, and constructing a part of a central portion 10A from the planned base level 24 upward to construct a preceding floor 17A in the central area 20A, and a step S4 of repeating construction of the rest of the central portion 10A in the central area 20A and excavation of the ground 2 from the preceding floor 17B downward to construct an outer peripheral portion 10B in the outer peripheral area 20B.SELECTED DRAWING: Figure 3

Description

The present invention relates to a method of constructing a building having an underground structure.

Conventionally, when constructing a super high-rise building having a large-scale underground structure, a reverse construction method may be used. In this reverse construction method, first, the floor slab on the first floor is constructed as a preceding floor. Next, while using this preceding floor as a support work, the ground excavation and the construction of the underground structure are sequentially repeated downward, and the ground structure is constructed upward from the preceding floor.
In this reverse construction method, the steel frame construction on the ground floor precedes the construction of the foundation structure. Therefore, during the period until the foundation frame is completed, the vertical load applied to the structural columns becomes large, and it is necessary to increase the pile length and the pile diameter of the piles that support the structural columns, which increases the construction cost. there were. In addition, when the height of the building is high, the bearing capacity of the piles was insufficient, and it was sometimes necessary to suspend the steel frame construction on the ground floor. Furthermore, in the case of a building equipped with a low-rise part around the high-rise part of the super high-rise part, since the whole underground skeleton is integrated, the number of structure columns will increase by the number of underground columns, which may further increase the cost. ..
On the other hand, even if it is a large-scale underground structure, if a direct foundation that does not require piles can be adopted, the sequential driving method is more cost effective than the reverse driving method, but the construction period is prolonged. was there.
For example, as a method of constructing a large-scale underground structure, there is a method of Patent Document 3, but if the construction of the skeleton of the outer peripheral portion is not completed, excavation of the central portion cannot be started, and when the central portion is a super high-rise building. Had the problem of extending the construction period.
Further, in the method of Patent Document 4, the outer peripheral portion is formed by the reverse driving method and the central portion is formed by the normal driving method. However, since a crossbeam is required in the central area, the construction of the underground structure can be promoted smoothly. Was difficult.

Patent Document 1 describes a method for constructing an underground structure including a high-rise part and a low-rise part of a building. In this method of constructing an underground structure, when constructing an underground skeleton, a reverse construction method is used in which the underground skeleton is constructed while excavating the ground, so that there is no difference in the amount of subsidence during the construction process. For underground columns that support the section, vertical displacement is suppressed by placing concrete first. On the other hand, for the underground columns that support the low-rise part of the building, concrete placement is delayed to allow vertical displacement to prevent uneven settlement.
Patent Document 2 describes a method for constructing an underground structure in which a basic structure of a new building is constructed while leaving a part of the existing underground structure. Specifically, after dismantling the upper skeleton, the existing underground skeleton is left in place, the underground skeleton is reinforced by columns and girders, and a gantry is installed. Next, the underground structure is constructed in a short period of time by performing pile work on the underground structure with a rock auger or a full-circle rotary excavator.
Further, Patent Document 3 describes a method for constructing an underground structure in which the center portion of the building is formed by a sequential driving method and the outer peripheral portion is constructed by a reverse driving method. In this method of constructing an underground structure, first, a retaining wall is constructed around an existing underground structure. Next, while sequentially dismantling the existing underground structure, an outer peripheral ring is constructed on the outer peripheral portion of the new underground structure, and the outer peripheral portion of the new underground structure is constructed from the upper layer to the lower layer. After that, the center of the new underground structure will be built inside the outer ring. However, in Patent Document 3, a space where an earth retaining wall can be constructed is required between the existing underground structure and the site boundary.
Patent Document 4 discloses a method for constructing an underground structure in which a new underground structure is constructed at a place where an existing underground structure is dismantled. In this method, the new underground structure is divided into an outer peripheral area and a central area, and in the outer peripheral area, the underground structure is constructed by the reverse construction method, and in the central area, support work is carried out using shelf piles and beams. Will be erected and an underground structure will be constructed by the progressive construction method. However, in the method of constructing an underground structure of Patent Document 4, since a temporary structure such as a shelf pile or a crossbeam is provided in the central area, it is difficult to smoothly perform excavation in the central area or construction of an underground structure. It was

Japanese Patent No. 5171902 JP, 2017-020265, A JP2012-107430A Japanese Patent No. 6103667

However, in the method of constructing an underground structure as disclosed in Patent Document 1, it is difficult to smoothly perform excavation and construction of an underground structure in the central area because provisional structures such as shelf piles and beams are provided in the central area. Met.

An object of the present invention is to provide a method of constructing a building, which is capable of smoothly excavating the ground and constructing an underground structure in an inner area, for a building having an underground structure.

The present inventors, as a method of constructing a high-rise building having an underground skeleton, after partitioning the building into a high-rise part and a low-rise part, perform ground excavation immediately below the high-rise part, and move upward from the excavated bottom. Constructing an underground structure by the sequential driving method, and using the underground structure directly under the high-rise portion as a mountain retaining for the area directly under the low-rise part, construct the underground structure by the reverse-injection method, using both the forward-injection method and the reverse-injection method. Then, the present invention has been accomplished by focusing on the fact that the ground frame construction work can be started early and a short construction period can be realized.
A method of constructing a building according to a first aspect of the present invention is a method of constructing a building (for example, a building 1 described below) having an underground structure (for example, an underground structure 10 described below), wherein the underground structure is viewed in a plan view. , An inner structure (for example, a central portion 10A described later) built in an inner area (for example, a central area 20A described later) and an outer area outside the inner area (for example, a peripheral area 20B described later). And an outer structure (for example, an outer peripheral portion 10B described later), and a temporary wall (for example, a temporary wall 22 described later) is constructed at a boundary between the inner area and the outer area, and A first step (for example, step S1 described below) of constructing a true pillar (for example, true pillar 23 described later) in the ground of the area (for example, ground 2 described later), and the inner area side of the temporary wall Second step of excavating the ground in the inner area to the bottom depth of the inner structure while driving a ground anchor (for example, a ground anchor 25 described later) from the wall surface of the inner area toward the ground in the outer area (for example, described later). Step S2) and a floor slab of a predetermined floor (for example, the first floor) of the outer structure (for example, a floor slab 16 of the first floor described later) of the outer structure in the outer area is used as a preceding floor (for example, a preceding floor described later 17B), the preceding floor is supported by the true column, and in the inner area, a part of the inner structure goes upward from a surface with a floor (for example, a surface with a floor 24 described later). (For example, a steel frame column 26 and a steel beam 27 of a central portion 10A described later is constructed, supported by a part of the inner structure, and a floor slab of a predetermined floor (for example, the first floor) is used as a preceding floor (for example, later described). In the third area (for example, step S3 described later) to be constructed as the preceding floor 17A) and a ground structure (for example, the above-mentioned skeleton skeleton 11 described later) are constructed from the preceding floor to the inside area. And constructing the rest of the inner structure and repeating the construction of the outer structure by excavating the ground while removing the ground anchor downward from the preceding floor in the outer area. It is characterized by including four steps (for example, step S4 described later).
The above-mentioned temporary wall is a wall that is temporarily installed at the boundary between the inner area and the outer area in the process of building the building, and for example, a partition pile to be described later and a horizontal sheet pile installed between the partition piles. Composed.

According to this invention, the underground structure is constructed in the outer area by the reverse casting method, and the underground structure is constructed in the inner area by the sequential casting method. At this time, a temporary wall was provided at the boundary between the outer area and the inner area, and a ground anchor supporting the temporary wall was fixed in the ground of the outer area. Therefore, temporary structures such as shelving piles and beams are not required in the inner area, so that excavation in the inner area and construction of an underground structure can be smoothly performed. Further, since the temporary wall and the ground anchor serve as a mountain retaining member that holds the ground in the outer area, the stability of the surrounding ground adjacent to the construction site can be enhanced.

In the method of constructing a building according to a second aspect of the invention, in the second step, the ground anchor is driven into the ground of the outer area through the space between the structural columns, and the fixing body of the ground anchor is ground in the outer area. It is characterized by being placed inside.

According to this invention, the true pillar is driven into the ground in the outer area, and the ground anchor is installed between the true pillars. Therefore, it is not necessary to secure a land outside the building site only to fix the ground anchor, and the ground anchor can be easily installed even if the site is narrow.
In addition, since the ground anchor fixing body is installed in the ground in the outer area, various forms can be adopted as the ground anchor fixing body, and the ground anchor can be removed relatively easily.
Further, the ground anchor can be easily removed according to the progress of the ground excavation work in the outer area.

The method of constructing a building according to a third aspect of the present invention is to excavate the ground in the inner area to a predetermined depth and repeat the operation of driving the ground anchor into the wall surface exposed by the excavation of the temporary wall, thereby vertically moving the ground anchor. It is characterized in that a plurality of stages are provided.

According to the present invention, since the ground anchors are provided in a plurality of upper and lower stages, the temporary wall can be reliably supported by the ground anchor even when the excavation depth is deep and the temporary wall is high.

According to the present invention, it is possible to provide a method of constructing a building that can smoothly proceed with excavation of the ground and construction of an underground structure in an inner area, targeting a building having an underground structure.

It is a typical longitudinal cross-sectional view of the building constructed|assembled by the building construction method which concerns on one Embodiment of this invention. 2 is a schematic cross-sectional view of an underground structure of the building shown in FIG. 1. FIG. It is a flowchart which shows the construction procedure of a building. It is explanatory drawing of the construction procedure of a building (the part 1: drive-in process of the partition pile which comprises a temporary wall, the construction process of the construction pillar and SMW wall in an outer peripheral area). It is explanatory drawing of the construction procedure of a building (the part 2: driving process of the ground anchor in a central area). It is explanatory drawing of the construction procedure of a building (the part 3: The construction process of the preceding floor in an outer peripheral area, the steel frame construction in the center area, and the construction process of a preceding floor). It is explanatory drawing of the construction procedure of a building (Part 4: construction process of the underground skeleton in the outer peripheral area, construction process of the underground skeleton in the central area).

The present invention, as a method of constructing a high-rise building having an underground skeleton, for the central area directly under the high-rise part of the building, construct an underground skeleton by performing ground excavation by the progressive construction method, and for the outer peripheral area immediately below the low-rise part of the building. Is a method for constructing an underground skeleton by the reverse casting method, in which the center area is sequentially hammered and the outer area is hammered. As a result, the construction work on the ground can be started early and the construction period can be shortened.
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic vertical sectional view of a building 1 constructed by a building construction method according to an embodiment of the present invention. FIG. 2 is a schematic cross-sectional view of the underground structure 10 of the building 1.
The building 1 includes an underground skeleton 10 as an underground structure of steel reinforced concrete structure, and an above-ground skeleton 11 as an above-ground structure of steel frame constructed on the underground skeleton 10.

The underground structure 10 includes a central portion 10A as an inner structural body and an outer peripheral portion 10B as an outer structural body that is annularly constructed around the central portion 10A (in the plan view). Further, the underground skeleton 10 is, in a longitudinal sectional view, a mat slab 12 which is a solid foundation, a pile 13 which is a pile foundation provided directly below the mat slab foundation of the outer peripheral portion 10B, a pillar 14 on each floor, and a beam 15 on each floor. The floor slab 16 on each floor is provided. As shown in FIG. 1, no pile is provided in the central portion 10A, and the pile 13 is provided only in the outer peripheral portion 10B.
The ground structure 11 is composed of a high-rise part and a low-rise part built around the high-rise part. The central portion 10A of the underground structure 10 is located directly below the high-rise part, and the outer peripheral part 10B of the underground structure 10 is located directly below the low-rise part.

Hereinafter, the procedure for constructing the building 1 will be described with reference to the flowchart of FIG.
First, in plan view, an area in which the central portion 10A of the underground structure 10 is constructed is a central area 20A as an inner area, and an area in which the outer peripheral portion 10B is constructed is an outer peripheral area 20B as an outer area (see FIG. 2). ). The outer peripheral area 20B has a ring shape surrounding the central area 20A.

In step S1, as shown in FIG. 4, partition piles forming the temporary wall 22 are driven at a predetermined interval at the boundary between the central area 20A and the outer peripheral area 20B. Further, in the outer peripheral area, the SMW wall 21 as a mountain retaining wall is constructed along the outer periphery of the building 1 in the ground 2, and the true pillar 23 is embedded in the ground 2 to construct the pile 13.
In step S2, as shown in FIG. 5, the ground anchor 25 is driven into the ground 2 of the central area 20A from the wall surface of the temporary wall 22 on the side of the central area 20A toward the ground 2 of the outer peripheral area 20B. Excavate to the depth of the bottom surface of the mat slab 12 (surface 24 with floor).
Specifically, the ground 2 in the central area 20A is excavated to a predetermined depth, and a horizontal sheet pile is fitted between the partition piles exposed by the excavation to construct the temporary wall 22. Then, the ground anchor 25 is driven into the exposed wall surface of the temporary wall 22. At this time, the ground anchor 25 is driven through between the true columns 23 of the ground 2 in the outer peripheral area 20B and between the piles 13 to arrange the fixing body at the tip of the ground anchor 25 in the ground 2 in the outer peripheral area 20B. .. By repeating this work, the ground anchor 25 is provided in a plurality of upper and lower stages, and the floor-attached surface 24 is excavated.
The temporary wall 22 is a wall temporarily installed at the boundary between the central area 20A and the outer peripheral area 20B in the process of building the building 1. Since the temporary wall 22 is pulled toward the ground 2 side of the outer peripheral area 20B by installing the ground anchor 25, the temporary wall 22 is retained even when the ground 2 in the central area 20A is being excavated.

In step S3, as shown in FIG. 6, in the outer peripheral area 20B, the structure columns 23 are supported to construct the preceding floor 17B of the outer peripheral portion 10B, and in the central area 20A, the steel frame pillars 26 of the central portion 10A. The leading floor 17A of the central portion 10A is constructed by supporting the first floor as the first floor 17 and the entire first floor slab is constructed. Specifically, the outer peripheral area 20B is appropriately excavated, the beam 15 and the floor slab 16 on the first floor of the outer peripheral portion 10B are constructed as a preceding floor 17B, and the preceding floor 17B is supported by the true column 23. In this way, even if the upper part of the ground 2 in the outer peripheral area 20B is excavated to construct the outer peripheral part 10B, the ground anchor 25 is not driven into the upper part of the ground 2 and therefore does not interfere with the ground anchor 25.

Further, in the central area 20A, the steel framing of the steel frame columns 26 and the steel beam 27 of the central portion 10A is performed upward from the floor-attached surface 24. Here, for the purpose of shortening the construction period, a bundle member 28 made of precast concrete is installed on the bottom surface 24 of the steel column 26, and the steel column 26 is built on the bundle member 28. Note that the present invention is not limited to this, and the lower portion 12A of the mat slab (shown by the broken line in FIG. 6) may be constructed, and the steel column 26 may be built on this.
Further, in the central area 20A, the beam 15 and the floor slab 16 on the first floor, which are integrated with the preceding floor 17B in the outer peripheral area, are constructed as the preceding floor 17A. As a result, the first-floor preceding floor 17 is completed over the entire surface, and thereafter, it becomes possible to proceed with construction above and below the first-floor preceding floor 17 at the same time.

In step S4, as shown in FIG. 7, in the entire area (the central area 20A and the outer peripheral area 20B), the construction of the above-ground building 11 from the preceding floor 17 on the first floor is started.
Further, in the central area 20A, the remaining skeleton of the central portion 10A is constructed. Here, the construction of the floor frame (the beam 15 and the floor slab 16) of each floor of the central portion 10A does not necessarily have to be performed from the lower layer to the upper layer.
In the outer peripheral area 20B, the ground 2 is excavated downward from the preceding floor 17B while the ground anchor 25 is removed to construct the beam 15 and the floor slab 16 on the basement floor of the outer peripheral portion 10B. After that, such excavation and construction of the underground structure are repeated. In this excavation, since the excavation depth is shallow, the earth pressure acting on the SMW wall 21 is small, and the beam 15 and the floor slab 16 already constructed in the outer peripheral area 20B function as a support for the SMW wall 21. Therefore, excavation can proceed without waiting for the construction of the beam 15 and the floor slab 16 in the central portion 10A. Therefore, the level of the floor skeleton constructed in the central portion 10A and the level of the floor skeleton constructed in the outer peripheral portion 10B do not necessarily have to match.

According to this embodiment, there are the following effects.
(1) In the outer peripheral area 20B, the outer peripheral portion 10B of the underground skeleton 10 is constructed by the reverse striking method, and in the central area 20A, the central portion 10A of the underground skeleton 10 is constructed by the sequential striking method. At this time, a temporary wall 22 was provided at the boundary between the outer peripheral area 20B and the central area 20A, and the ground anchor 25 of this temporary wall 22 was fixed in the ground 2 of the outer peripheral area 20B. Therefore, temporary structures such as shelving piles and beams are unnecessary in the central area 20A, so that excavation in the central area 20A and construction of the underground skeleton 10 can be proceeded smoothly. Further, since the temporary wall 22 and the ground anchor 25 exert the function of retaining the ground 2 in the outer peripheral area 20B, the stability of the surrounding ground adjacent to the construction site can be enhanced.

(2) The structure columns 23 are driven into the ground 2 in the outer peripheral area 20B, and the ground anchors 25 are installed between the structure columns 23 and the piles 13. Therefore, it is not necessary to secure a land outside the building site only for fixing the ground anchor 25, and the ground anchor 25 can be easily installed even if the site is narrow.
Further, since the fixing body of the ground anchor 25 is installed in the ground 2 of the outer peripheral area 20B, various forms can be adopted as the fixing body of the ground anchor 25 and the ground anchor 25 can be removed relatively easily.
Further, the ground anchor 25 can be easily removed according to the progress of the excavation work of the ground 2 in the outer peripheral area 20B.

(3) Since the ground anchor 25 is provided in a plurality of upper and lower stages, the temporary wall 22 can be reliably supported by the ground anchor 25 even if the excavation depth is deep and the temporary wall 22 is high.
(4) For the building 1 having the underground skeleton 10, the central part 10A immediately below the high-rise part of the building 1 is constructed by the sequential construction method, and the outer peripheral part 10B immediately below the low-rise part of the building 1 is constructed by the reverse construction method. Thus, it is possible to realize a method for constructing an underground structure that is advantageous in both cost and construction period. In particular, in the building 1, since the central portion 10A is directly supported by the solid foundation instead of the pile, the cost of constructing the underground skeleton 10 can be reduced, and the construction period can be shortened.

It should be noted that the present invention is not limited to the above-described embodiment, and modifications, improvements, etc. within the scope of achieving the object of the present invention are included in the present invention.
For example, in the above embodiment, the ground anchor is driven in a plurality of steps, but the present invention is not limited to this, and the ground anchor may be driven in only one step.
Further, in the above embodiment, the preceding floor 17A in the central area 20A and the preceding floor 17B in the outer peripheral area 20B are provided at the first floor level, but the present invention is not limited to this, and the preceding floor 17A and the preceding floor 17B are set at different floor levels. It may be provided.
Further, in the above embodiment, the foundation of the central area 20A is a direct foundation made of a solid foundation (mat slab 12), but the foundation is not limited to this and may be a pile foundation.

1... Building 2... Ground 10... Underground structure (underground structure) 10A... Central part (inner structure)
10B... Peripheral part (outer structure) 11... Ground structure (ground structure)
12...mat slab 12A...bottom of mat slab 13...pile 14...pillar 15...beam 16...floor slab 17...preceding floor on the first floor 17A...preceding floor in the center 17B...preceding floor on the outer periphery 20A...central area (inner area ) 20B... Outer area (outer area)
21... SMW wall 22... Temporary wall 23... Structural column 24... Floor surface 25... Ground anchor 26... Steel column 27... Steel beam 28... Bundle member

Claims (3)

A method of constructing a building having an underground structure,
The underground structure, in plan view, an inner structure constructed in an inner area, and an outer structure constructed in an outer area outside the inner area, and is configured,
A first step of building a temporary wall at the boundary between the inner area and the outer area, and building a true pillar in the ground of the outer area,
A second step of excavating the ground in the inner area to the bottom depth of the inner structure while driving the ground anchor from the wall surface on the inner area side of the temporary wall toward the ground in the outer area;
In the outer area, a floor slab of a predetermined floor of the outer structure is constructed as a preceding floor, and the preceding floor is supported by the structural pillars, and in the inner area, from the floor-attached surface upward. A third step of constructing a part of the inner structure, supporting a part of the inner structure to construct a floor slab of a predetermined floor as a preceding floor, and
While constructing a ground structure upward from the preceding floor, construct the rest of the inner structure in the inner area, and in the outer area, downward from the preceding floor, the ground anchor. And a fourth step of repeating the step of excavating the ground while removing the ground to construct the outer structure, the method for constructing a building. In the second step, the ground anchor is driven into the ground in the outer area so as to pass through between the true columns, and the fixing body of the ground anchor is arranged in the ground in the outer area. The method for constructing a building according to 1. In the second step, by excavating the ground in the inner area to a predetermined depth and driving the ground anchor into the wall surface of the temporary wall exposed by the excavation, the ground anchors may be provided in a plurality of upper and lower stages. The method for constructing a building according to claim 1 or 2, which is characterized.

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