JP6920039B2 - How to dismantle the existing underground skeleton - Google Patents

Description

The present invention relates to a method of disassembling an existing underground skeleton.

Conventionally, the existing underground skeleton has been dismantled (see Patent Documents 1 to 5).
In Patent Document 1, first, a reinforcing wall is formed on the outer peripheral frame of the existing underground skeleton, and the internal skeleton of the existing underground skeleton is changed from the first basement floor to the lowest floor, leaving a part of the skeleton that supports the earth pressure of the reinforcing wall. Dismantle until. Next, while erection of a girder on the existing underground skeleton, the steps of dismantling the reinforcing wall and the skeleton left directly under the girder are sequentially repeated.

In Patent Document 2, first, a retaining wall is constructed inside the existing underground skeleton of an existing building, and dismantled glass or concrete is filled between the retaining wall and the outer peripheral wall of the existing underground skeleton to form the existing underground skeleton. The retaining wall supports the earth pressure acting on the outer wall. In this state, the underground frame of the new building will be constructed inside the retaining wall.

In Patent Document 3, the above-ground part of the building is dismantled and the underground structure part is backfilled with the dismantling glass, and the pillars and beams in the underground part are left in a batless shape while rejecting the backfilled dismantling glass. The process of dismantling the underground part and the process of compacting the dismantled beams to make the construction ground are performed.

In Patent Document 4, an opening is formed in each floor slab of the underground skeleton, then the dismantling means is carried into the lowermost layer portion through the opening, and then the dismantling means performs the dismantling work on the lowermost layer portion. While backfilling the dismantled part, the process of transporting the dismantling means onto the backfilled soil and backfilling the dismantled part while performing dismantling work on the structural skeleton such as the slab on the immediate upper floor by the dismantling means The process to be performed is repeated in sequence toward the upper floors.

Patent Document 5 is a method of constructing a new building using an existing building, in which the process of dismantling the above-ground skeleton of the existing building and the work on the existing underground slab of the existing building or the upper part of the girder of the existing building. Using the process of installing the demolition, the process of forming openings in the existing underground slab on each basement floor of the existing building, and the lifting device placed on the work platform, on the floor of the nth basement floor of the existing building. Includes the process of erection of new underground pillars.

Japanese Unexamined Patent Publication No. 2011-163074 Japanese Unexamined Patent Publication No. 2006-266036 JP-A-2010-189960 Japanese Unexamined Patent Publication No. 7-18881 Japanese Patent No. 5925231

In the method of rebuilding a building in Patent Document 1, after dismantling an existing underground skeleton while leaving a part of the skeleton on the outer periphery, a girder is erected inside the existing underground skeleton, and reinforcement left directly under the girder is erected. Dismantle the walls and skeleton. Therefore, the girder becomes an obstacle to the dismantling work, which may prolong the construction period.

Further, in the method of rebuilding a building in Patent Document 2, since earth pressure is applied to a self-supporting retaining wall, there is a problem that if the existing underground skeleton is deep, the retaining wall becomes large and the construction cost increases. ..

Further, in the method of dismantling a building in Patent Document 3, the underground part is dismantled while leaving the columns and beams in the underground part in a buttress shape while rejecting the dismantling glass, which requires a lot of work and prolongs the construction period. There was a risk.

Further, in the method of dismantling the underground skeleton of Patent Document 4, the backfilled soil is used as a support for the retaining wall by backfilling the dismantled part by the dismantling means. In some cases, the acting earth pressure could not be supported.

Further, in the method of constructing a building in Patent Document 5, a new underground column of a new building can be constructed at an early stage, but a method of dismantling an existing underground skeleton is not specified.

An object of the present invention is to provide a method for dismantling an existing underground skeleton that can reduce the construction cost without prolonging the construction period even when the space between the existing underground skeleton and the boundary between adjacent lands is narrow.

As a method of rebuilding an existing building built in a densely populated area, the present inventors use the existing underground outer wall as a retaining wall, suspend the demolition heavy machine to the lowest basement floor of the existing underground skeleton, and then use the demolition heavy machine. Then, when the existing underground skeleton is dismantled from the bottom to the top, the existing underground floor slab on the upper floor and the existing underground pillar support the underground skeleton as a support work, without installing a new support work. Focusing on the fact that the existing underground skeleton can be disassembled and removed, the invention of the method for disassembling the existing underground skeleton of the present invention was made.
The features of the present invention are that the existing floor slabs and existing underground pillars on the upper floor function as support works to support the underground skeleton on the lower floor, and the existing floor slabs and existing underground pillars on the upper floor support the floor to be dismantled. In this state, the skeleton other than the existing underground pillars is dismantled for each floor to be dismantled, and the dismantled parts are backfilled and dismantled sequentially from the bottom to the top.

The method of disassembling the existing underground skeleton of the first invention is a method of disassembling the existing underground skeleton (for example, the existing underground skeleton 2 described later), and is a method of disassembling the existing underground skeleton (for example, the existing floor slab described later). In 16), a step of providing an opening (for example, an opening 20 described later) from the ground surface to the lowest basement floor (for example, step S1 described later) and the existing underground skeleton from the lowest basement floor toward the ground surface. A step of backfilling while disassembling the existing underground skeleton while leaving the existing pillars of the existing underground skeleton (for example, the existing pillar 14 described later) (for example, steps S2 to S7 described later) is provided. It is a feature.

According to the present invention, the existing underground outer wall is used as a retaining wall, and by using the existing floor slab and the existing pillar as the support for the existing underground outer wall facing each other, a separate support is erected between the existing underground outer walls facing each other. The existing underground skeleton can be dismantled and removed. Therefore, the existing underground skeleton can be dismantled in a short construction period and at low cost.

The method of dismantling the existing underground skeleton of the second invention is a method of dismantling the existing underground skeleton, and constructs a new wall body (for example, a retaining wall 21 described later) outside the existing underground outer wall of the existing underground skeleton. (For example, step S11 described later), an opening is provided in the existing floor slab of the existing underground skeleton from the ground surface to the lowest basement floor, and stress is transmitted between the existing underground outer wall and the wall body. A step of providing a member (for example, a backfill member 22 described later) (for example, steps S12 to S14 described later) and an existing pillar (for example) of the existing underground skeleton from the lowest basement floor of the existing underground skeleton toward the ground surface. It is characterized by comprising a step of backfilling while disassembling the existing underground skeleton while leaving the existing pillar 14) described later (for example, steps S15 to S21 described later).

Here, examples of the wall body include a retaining wall and a continuous reinforced concrete wall.
According to the present invention, a new wall body is constructed outside the existing underground outer wall, and the new wall body is supported by the existing floor slab by a stress transmission member. Then, by using the existing floor slab and the existing pillar as the support work of the facing wall bodies, the existing underground skeleton can be dismantled and removed without separately constructing the support work between the facing wall bodies. Therefore, the existing underground skeleton can be dismantled in a short construction period and at low cost.

In the method of dismantling the existing underground skeleton of the third invention, the existing underground skeleton is dismantled in the step of backfilling while dismantling the existing underground skeleton from the lowest basement floor of the existing underground skeleton toward the ground surface. It is characterized in that the work of backfilling is repeated for each floor or for each of a plurality of floors.

According to the present invention, even in an existing building in which an existing underground skeleton is provided near the boundary line of the adjacent land, the existing underground skeleton can be dismantled in a short construction period and at low cost.

According to the present invention, it is possible to prevent the construction period from becoming long and reduce the construction cost.

It is a vertical sectional view of the existing building to which the 1st dismantling method of the existing underground skeleton which concerns on 1st Embodiment of this invention is applied. It is a flowchart of the first dismantling method of an existing underground skeleton. It is explanatory drawing of the 1st dismantling method of the existing underground skeleton (the first, the dismantling explanatory view of the lowermost part of the existing underground skeleton). It is explanatory drawing of the 1st dismantling method of the existing underground skeleton (the second, dismantling explanatory view from the lowest floor of the existing underground skeleton to the first basement floor level). It is explanatory drawing of the 1st dismantling method of the existing underground skeleton (3, dismantling explanatory view of the 1st basement floor part of the existing underground skeleton). It is explanatory drawing of the 1st dismantling method of the existing underground skeleton (the fourth, the backfilling explanatory view of the surface layer ground part). It is a flowchart of the 2nd dismantling method of the existing underground skeleton which concerns on 2nd Embodiment of this invention. It is explanatory drawing of the 2nd dismantling method of the existing underground skeleton (the first, the explanatory view of the mountain retaining wall to be constructed outside the existing underground skeleton). It is explanatory drawing of the 2nd dismantling method of the existing underground skeleton (the second, the explanatory view of the backfill member provided between the existing underground skeleton and the mountain retaining wall). It is explanatory drawing of the 2nd dismantling method of the existing underground skeleton (3, explanatory drawing of the backfill member provided between the existing underground skeleton and the mountain retaining wall). It is explanatory drawing of the 2nd dismantling method of the existing underground skeleton (4, explanatory drawing of the diagonal beam provided between a mountain retaining wall and an existing underground skeleton). It is explanatory drawing of the 2nd dismantling method of the existing underground skeleton (No. 5, dismantling explanatory view from the lowest floor of the existing underground skeleton to the second basement floor level). It is explanatory drawing of the 2nd dismantling method of the existing underground skeleton (6, dismantling explanatory view from the 2nd basement floor to the 1st basement floor level of the existing underground skeleton). It is explanatory drawing of the 2nd dismantling method of the existing underground skeleton (7, the backfilling explanatory view of the 1st basement floor part of the existing underground skeleton). It is explanatory drawing of the 2nd dismantling method of the existing underground skeleton (the 8, backfilling explanatory view of the surface layer ground part).

The present invention presents a method of dismantling an existing underground skeleton using an existing underground outer wall as a mountain retaining wall (first embodiment) and a method of dismantling an existing underground skeleton in which a new retaining wall is provided outside the existing underground outer wall (second embodiment). Embodiment). Unlike the first embodiment, the second embodiment is characterized in that the existing underground outer wall on the upper basement floor can be dismantled at an early stage by providing a backfill member between the existing underground outer wall and the newly constructed retaining wall. .. According to the present invention, when the existing underground skeleton is dismantled sequentially from the bottom to the top, it is not necessary to provide a support as a separate member in order for the existing underground floor slab on the upper floor to support the underground skeleton as a support. , The existing underground skeleton can be dismantled.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description of the following embodiments, the same components will be designated by the same reference numerals, and the description thereof will be omitted or simplified.
[First Embodiment]
FIG. 1 is a vertical cross-sectional view of an existing building 1 to which the method of dismantling an existing underground skeleton according to the first embodiment of the present invention is applied.
The existing building 1 includes an existing underground skeleton 2 constructed underground and an existing above-ground skeleton 3 constructed on the existing underground skeleton 2.

The existing underground skeleton 2 is a reinforced concrete structure up to the second basement floor.
The existing underground skeleton 2 includes an existing column 10, a footing 11 provided on the existing column 10, a foundation beam 12 connecting the footings 11, a pressure-resistant plate 13 provided between the foundation beams 12, and a foundation beam. Existing columns 14 provided on the 12, existing beams 15 erected between the existing columns 14, existing floor slabs 16 provided between the existing beams 15 and between the foundation beams 12, located on the outer periphery. The existing underground outer wall 17 provided between the existing outer peripheral column 14a and the existing outer peripheral beam 15a is provided.

Hereinafter, a method of disassembling the existing underground skeleton 2 after disassembling the existing above-ground skeleton 3 will be described with reference to the flowchart of FIG.
In step S1, as shown in FIG. 3, a part of the existing floor slabs 16 on the first floor and the first basement floor is dismantled, and openings are opened in each floor from the ground surface to the second basement floor, which is the lowest basement floor. 20 is formed.

In step S2, as shown in FIG. 3, the foundation skeleton of the existing underground skeleton 2 is dismantled, leaving the outer peripheral foundation beam 12a, the footing 11, the existing column 14, and the existing outer peripheral column 14a. Specifically, a lifting device is placed on the first floor or a work platform provided on the ground, and the lifting device is used to reach the lowest floor of the existing underground skeleton through the opening 20 provided in the existing floor slab 16. Suspend the heavy equipment for dismantling. Then, using this heavy machine for dismantling, the foundation beam 12, the pressure plate 13, and the existing floor slab 16 at the floor level of the second basement floor are dismantled. The dismantled material is lifted to the first floor through the opening 20 and carried out.

In step S3, as shown in FIG. 4, primary backfilling is performed. Specifically, while dismantling the outer peripheral foundation beam 12a and the existing underground outer wall 17 rising up to the second basement floor, backfilling is performed from the lowest basement floor to the level below the first basement floor beam with ground-improved earth and sand.

In step S4, as shown in FIG. 4, the existing basement floor level skeleton of the existing underground skeleton 2 is dismantled, leaving the existing outer peripheral beam 15a, the existing pillar 14, and the existing outer peripheral pillar 14a. Specifically, the existing beam 15 and the existing floor slab 16 at the first basement floor level will be dismantled. The dismantled material is lifted to the first floor through the opening 20 and carried out.

In step S5, as shown in FIG. 5, secondary backfilling is performed. Specifically, while dismantling the existing outer peripheral beam 15a on the first basement floor level and the existing underground outer wall 17 rising on the first basement floor, backfilling is performed from the first basement floor to the lower level of the first basement beam with ground-improved earth and sand. ..

In step S6, as shown in FIG. 5, the existing underground skeleton 2 is dismantled at the floor level of the first basement floor, leaving the existing columns 14 and the existing outer peripheral columns 14a. Specifically, the existing beam 15 and the existing floor slab 16 at the first floor level are dismantled.

In step S7, as shown in FIG. 6, tertiary backfilling is performed. Specifically, the surface ground portion is backfilled with earth and sand that has been ground-improved to the ground level.

In step S8, the existing pillar 14, the existing outer peripheral pillar 14a, the footing 11, and the existing pile 10 are crushed or pulled out and removed by the all-swivel all-casing method or the like. The removal method is not particularly limited.

According to this embodiment, there are the following effects.
(1) The existing underground outer wall 17 is used as a retaining wall, and the existing floor slab 16, the existing beam 15, and the existing columns 14 and 14a are used as support works for the existing underground outer wall 17 (existing outer peripheral beam 15a) facing each other. The existing underground skeleton 2 can be disassembled and removed without erection of support work between the existing underground outer walls 17. Therefore, the existing underground skeleton 2 can be dismantled in a short construction period and at low cost.

(2) In the present invention, the existing columns 14 and 14a are retained, and the existing floor slab 16 supported by the existing columns 14 and 14a is used as a support. Then, while the existing underground outer wall 17 (existing outer peripheral beam 15a) is supported by the existing floor slab 16, the existing underground skeleton 2 other than the existing pillar 14 is dismantled and removed for each floor, and formed by this dismantling work. The space that has been created is backfilled and closed. As a result, the existing underground skeleton 2 can be safely dismantled from the lowest floor toward the ground surface while securing the construction ground for each dismantled floor.
In the present embodiment, one cycle from dismantling to backfilling is carried out for each floor, but the present invention is not limited to this, and one cycle from dismantling to backfilling may be carried out for each of a plurality of floors.

(3) Even when the existing underground skeleton 2 and the adjacent land boundary are close to each other, the existing underground skeleton 2 can be dismantled in a short construction period and at low cost without providing a large-scale excavation area such as a slope slope on the outside of the existing underground skeleton 2. can.

[Second Embodiment]
FIG. 7 is a flowchart of a method of disassembling the existing underground skeleton according to the second embodiment of the present invention.
Hereinafter, the method of dismantling the existing building 1 will be described with reference to the flowchart of FIG. 7.

In step S11, as shown in FIG. 8, a retaining wall 21 as a wall body made of steel sheet piles is constructed on the outside of the existing underground outer wall 17 of the existing underground skeleton 2. The retaining wall 21 is not limited to the steel sheet pile wall, but may be a soil cement column wall, an RC continuous wall, an existing concrete column wall, or the like.

In step S12, as shown in FIG. 8, a backfill member 22 as a stress transmission member is constructed between the existing underground outer wall 17 and the retaining wall 21 at the height position of the first floor level. As a result, the backfill member 22 and the first-floor-level skeleton of the existing underground outer wall 17 play the role of a first-stage support that supports the earth pressure acting on the retaining wall 21.
In addition, a part of the existing floor slab 16 on the first floor will be dismantled to provide an opening 20.

In step S13, as shown in FIG. 9, the existing 1st basement floor rising skeleton of the existing underground skeleton 2 is dismantled, leaving the existing pillar 14 and the existing outer peripheral pillar 14a. Specifically, as in the first embodiment, the lifting device is used to suspend the dismantling heavy machine to the floor to be dismantled through the opening 20 provided in the existing floor slab 16, and the dismantling heavy machine is lifted. The existing underground outer wall 17 and a partition wall (not shown) are dismantled by using. The dismantled material is lifted to the first floor through the opening 20 and carried out. At this time, the ground between the existing underground outer wall 17 and the retaining wall 21 is also excavated and removed.

In step S14, as shown in FIG. 9, a backfill member 22 is constructed between the existing underground outer wall 17 and the retaining wall 21 at the height position of the first basement floor level. As a result, the backfill member 22 and the existing underground outer wall 17 serve as a second-stage support for supporting the earth pressure acting on the retaining wall 21.
In addition, a part of the existing floor slab 16 on the first basement floor will be dismantled to provide an opening 20.

In step S15, as shown in FIG. 10, the existing 2nd basement floor rising skeleton of the existing underground skeleton 2 is dismantled, leaving the existing pillar 14 and the existing outer peripheral pillar 14a. Specifically, the existing underground outer wall 17 and a partition wall (not shown) are dismantled, and the dismantled material is lifted to the first floor through the opening 20 and carried out. At this time, the ground between the existing underground outer wall 17 and the retaining wall 21 is also excavated and removed.

In step S16, as shown in FIG. 10, an oblique beam 23 is erected between the existing underground skeleton 2 and the retaining wall 21 at a height position on the second basement floor level. As a result, the diagonal girder 23 and the existing underground outer wall 17 serve as a third-stage support for supporting the earth pressure acting on the retaining wall 21.

In step S17, as shown in FIG. 11, the foundation skeleton of the existing underground skeleton 2 is disassembled, leaving the footing 11, the existing pillar 14, and the existing outer peripheral pillar 14a. Specifically, the foundation beam 12, the outer peripheral foundation beam 12a, the pressure plate 13, and the existing floor slab 16 on the second basement floor are dismantled, and the dismantled material is lifted to the first floor through the opening 20 and carried out.

In step S18, as shown in FIG. 12, primary backfilling is performed. Specifically, the ground is backfilled with earth and sand that has been improved to the floor level of the second basement floor, and the diagonal beam 23 is removed.

In step S19, as shown in FIG. 13, secondary backfilling is performed. Specifically, it will be backfilled with earth and sand with improved ground to the level below the beam on the first basement floor.

In step S20, as shown in FIG. 13, the existing underground skeleton 2 is dismantled at the floor level of the first basement floor, leaving the existing columns 14 and the existing outer peripheral columns 14a. Specifically, the existing beam 15, the existing outer peripheral beam 15a, and the existing floor slab 16 at the first basement floor level are dismantled, and the dismantled material is lifted to the first floor through the opening 20 and carried out.

In step S21, as shown in FIG. 14, tertiary backfilling is performed. Specifically, it will be backfilled with earth and sand that has been ground-improved to the level below the beam on the first floor.

In step S22, as shown in FIG. 14, the first floor level skeleton of the existing underground skeleton 2 is dismantled, leaving the existing pillar 14 and the existing outer peripheral pillar 14a. Specifically, the existing beam 15 at the first floor level, the existing outer peripheral beam 15a, and the existing floor slab 16 are dismantled.

In step S23, as shown in FIG. 15, fourth backfilling is performed. Specifically, it will be backfilled with earth and sand that has been improved to the ground level.

In step S24, the retaining wall 21, the existing pillar 14, the footing 11, and the existing pile 10 are crushed or pulled out and removed by a fully swivel all-casing method or the like.

According to this embodiment, in addition to the above-mentioned (2) and (3), the following effects are obtained.
(4) The retaining wall 21 was constructed in the vicinity of the outside of the existing underground outer wall 17, and the retaining wall 21 was supported by the existing floor slab 16 via the backfill member 22. Then, by using the existing floor slab 16, the existing beam 15, and the existing columns 14 and 14a as the support work of the facing mountain retaining wall 21, the existing support work is not erected between the facing mountain retaining walls 21. The underground skeleton 2 can be disassembled and removed. Therefore, the existing underground skeleton 2 can be dismantled in a short construction period and at low cost.

The present invention is not limited to the above-described embodiment, and modifications, improvements, and the like within the range in which the object of the present invention can be achieved are included in the present invention.
In the above-described first embodiment, in the primary backfilling step of step S3 and the secondary backfilling step of step S5, while dismantling the existing underground outer wall 17, the dismantled portion was backfilled with ground-improved earth and sand. However, the present invention is not limited to this, and the existing underground outer wall may be dismantled while the existing underground outer wall remains, and the existing underground outer wall may be removed together with the existing columns and existing piles in step S8. In this way, when the existing underground outer wall is retained and the inside of the existing underground skeleton is dismantled, the existing underground outer wall can prevent sediment and groundwater from flowing in from the outside of the existing underground skeleton.

Further, in the above-mentioned second embodiment, the retaining wall 21 is constructed as a wall body made of steel sheet piles on the outside of the existing underground outer wall 17 of the existing underground skeleton 2, but the present invention is not limited to this, and the underground outer wall of the new building is constructed. Then, it may be connected to the existing underground outer wall 17. In this case, the underground outer wall of the new building and the existing underground outer wall 17 are integrated into a composite wall, which has the same effect as (4) above.

Further, in the above-mentioned second embodiment, the oblique beam 23 is erected between the retaining wall 21 and the existing underground skeleton 2, but the present invention is not limited to this. That is, if the strength and rigidity of the retaining wall 21 can be sufficiently secured, it is not necessary to provide such an oblique beam.
In the first and second embodiments described above, the existing underground skeleton 2 is a reinforced concrete two-story underground structure, but the method of dismantling the existing underground skeleton of the present invention is limited to the scale of the existing underground skeleton. Not done.

1 ... Existing building 2 ... Existing underground skeleton 3 ... Existing above-ground skeleton 10 ... Pile 11 ... Footing 12 ... Foundation beam 12a ... Outer foundation beam 13 ... Pressure-resistant plate 14 ... Existing pillar 14a ... Existing outer pillar 15 ... Existing beam 15a ... Existing outer circumference Beam 16 ... Existing floor slab 17 ... Existing underground outer wall 20 ... Opening 21 ... Mountain retaining wall (wall body) 22 ... Backfill member (stress transmission member)
23 ... Diagonal beam

Claims (2)

It is a method of dismantling the existing underground skeleton,
The process of constructing a new wall body outside the existing underground outer wall of the existing underground skeleton, and
A step of providing an opening from the ground surface to the lowest basement floor in the existing floor slab of the existing underground skeleton, and providing a stress transmission member between the existing underground outer wall and the wall body at a height position of each floor level. When,
From the lowest basement floor of the existing underground skeleton to the ground level, the process of backfilling while dismantling the existing underground skeleton while leaving the existing pillars of the existing underground skeleton, and
A method for dismantling an existing underground skeleton, which comprises a step of crushing or pulling out the remaining existing pillars from the surface level using a heavy machine for dismantling. In the process of backfilling while dismantling the existing underground skeleton from the lowest basement floor to the ground level of the existing underground skeleton, the work of dismantling and backfilling the existing underground skeleton is repeated for each floor. The method for dismantling an existing underground skeleton according to claim 1.

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