JP2015055088A - Building construction method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To economically progress building construction while employing an inverted construction method.SOLUTION: In a building construction method using an inverted construction method, a pile hole 8 is excavated by a pile hole excavation method that does not use a stable liquid; a cement liquid 12 is injected in a depth range H set for a permanent steel base column 7 in the pile hole 8; and a lower end of a permanent steel column 6 is inserted into an upper end of an injection range of the cement liquid 12 and integrated therewith for construction of a building skeleton.

Description

  The present invention relates to a building construction method using a reverse driving method.

Conventionally, this kind of building construction method has been the construction of a construction pillar and construction work supporting the construction pillar before the underground excavation, and then the construction pillar and construction pillar. The basement part and the ground part of the building are constructed in parallel while supporting the load.
And since the construction stand pillar is often used as a support pile for the main construction, in order to ensure a predetermined hole diameter and strength, in the excavation, a stabilizing liquid is used to stabilize the hole wall. The diameter of the pile is secured by this, and after excavation, the concrete is filled in the excavation hole filled with the stabilizing liquid using the treme tube to ensure the strength. In addition, the structural pillar is integrated by inserting its lower end into the concrete before the concrete of the structural support pillar is hardened (see, for example, Patent Document 1).

JP-A-5-5312 (paragraph numbers [0008], [0009])

According to the conventional building construction method described above, in the construction of the pedestal column, it is carried out while filling the pile hole with the stabilizing liquid in the excavation process, but the used stabilizing liquid is appropriately treated as industrial waste. It must be applied, and the waste disposal costs a lot of money.
Furthermore, the stability of the stable liquid deteriorates due to the mixing of excavated soil and groundwater with use. Therefore, in order to maintain the physical properties, the bentonite concentration is controlled and adjusted, and slime mixed in the liquid is removed. It is necessary to carry out processing etc., and in addition to the need for a stabilizing liquid maintenance device for carrying out such processing, the stabilizing liquid is collected from the pile hole and fed to the stabilizing liquid maintenance device, or from the stabilizing liquid maintenance device A circulation device for feeding liquid into the pile hole is also required, resulting in high equipment costs.
Moreover, in order to ensure the quality as a support pile, since the concrete which can exhibit sufficient intensity | strength is used for a filler, material cost also becomes expensive.
As a result, the overall cost for building construction increases, and a reduction is desired.

  Accordingly, an object of the present invention is to provide a building construction method capable of solving the above-described problems and economically proceeding with the construction of a building while using a reverse driving method.

  A first characteristic configuration of the present invention is a building construction method using a reverse driving method, in which a pile hole is excavated by a pile hole excavation method that does not use a stabilizing liquid, and the depth of the pile hole used as a built-up pillar. Injecting cement liquid into the area, and inserting the lower end of the construction column into the upper end of the cement liquid injection range (depth range of the construction column) to build a building frame It is in.

According to the first characteristic configuration of the present invention, since the pile hole is excavated by the pile hole excavation method that does not use the stabilizing liquid, it is not necessary to use the stabilizing liquid maintaining device and the circulation device, and the efficiency is improved with simple construction equipment. As a result, it is possible to carry out excavation of pile holes, and it is possible to shorten the construction period and reduce equipment costs. .
In addition, since it is not necessary to dispose of the used stabilizing solution, it is possible to reduce the waste treatment cost.
Furthermore, since cement liquid is used for the construction stand pillar, cost reduction in both construction and material aspects can be achieved compared to using concrete.
As a result, the overall cost for building construction can be reduced.

  According to the second characteristic configuration of the present invention, the construction of the column slab is started after the foundation is completed after the construction of the column and the beam is performed in advance with the construction of the building frame.

According to the second characteristic configuration of the present invention, it is possible to reduce the load burden on the structural pillar and the structural base column by suppressing the weight of the frame until the foundation is completed as much as possible. It is possible to reduce the pile strength.
As a result, the economy of the entire building can be improved.

  According to a third characteristic configuration of the present invention, the foundation portion is a direct foundation, and the stem frame is a temporary pile.

  According to the 3rd characteristic structure of this invention, since the whole building can be supported by the foundation part which is a direct foundation, after completion of a building, it is not necessary to bear a load for a construction pillar. In other words, the pedestal column does not support all of the final load of the building, but it only needs to temporarily support the building load at the construction stage. You can achieve cost reduction.

  According to a fourth feature of the present invention, after the injection of the cement liquid into the pile hole, a poorly mixed cement that is poorer than the cement liquid in an upper range of the injection range (depth range of the stem column). The liquid is injected to stabilize the hole wall of the pile hole.

According to the fourth characteristic configuration of the present invention, since the pile hole is excavated by an excavation method that does not use a stabilizing liquid, there is a possibility that the hole wall collapses, but at least with respect to the upper range of the stem frame Can stabilize the hole wall by the injected poorly mixed cement liquid, and can prevent the soil from falling off and mixing in the range of the construction column where the normal cement liquid has been injected, and can maintain the pile quality. .
Furthermore, the poorly blended cement liquid itself has a lower strength after curing than a normal cement liquid, and therefore can be easily removed. Therefore, for example, when excavating the underground part of a building by the reverse driving method, even if poor cementitious cemented material adheres around the structural pillar, it can be easily removed, and construction in the underground part of the building Can be improved.

  According to a fifth characteristic configuration of the present invention, in the formation of the stem frame, a guide casing is installed in a state where a lower end portion is positioned in the vicinity of the upper portion of the cement liquid injection range (depth range of the stem column). In addition, between the lower end portion of the guide casing and the upper end portion of the cement liquid injection range, the poorly mixed cement liquid that is poorer than the cement liquid is injected to stabilize the hole wall of the pile hole. It is in.

According to the fifth feature of the present invention, the guide casing and the poorly mixed cement liquid can stabilize the hole wall above the stem frame and can more reliably prevent the soil around the hole from falling off.
In addition, since the adhesion between the poorly mixed cement liquid and the guide casing is lower than the adhesion between the normal cement liquid and the guide casing, it is difficult to resist when pulling out the guide casing, and the work proceeds smoothly. be able to.
Moreover, since it is not necessary to inject | pouring the poor mixing | blending cement liquid into the installation range of a guide casing, compared with inject | pouring upwards, the injection quantity can be reduced and the reduction of material cost can be aimed at more.
Therefore, preferable results can be obtained in terms of quality, construction, and economy of the construction stand pillar.

Front sectional view of the building Explanatory drawing showing the building construction procedure Explanatory drawing showing the building construction procedure Explanatory drawing showing the building construction procedure Explanatory drawing showing the building construction procedure Explanatory drawing showing the building construction procedure Explanatory diagram showing the installation procedure of the structural stem and structural pillar

  Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a building B constructed by adopting an embodiment of the building construction method of the present invention.
The building B is formed in a multi-level structure including an underground portion B0 and an above-ground portion B1, and is constructed by using a reverse driving method.
In the lowermost layer, a foundation part K that directly constitutes the foundation is provided, and on the foundation part K, pillars 1, beams 2, floor slabs 3, walls 4, etc. of each layer are provided.

  In building B, prior to the formation of the basement B0, the structural pillar 6 which becomes the leading underground column during the installation of the retaining wall 5 and the reverse driving method, and the structural pillar 6 It installs with the construction stand pillar 7 used as a support pile of.

A construction method of the building B will be described.
[1] The retaining wall 5 is installed at a position on the outer peripheral side of the basement B0, and a pile hole 8 for excavating the frame stand 7 is excavated below the planned position of the column 1 (see FIG. 2). .
In addition, the detailed installation method of the construction stem pillar 7 and the construction stem pillar 6 will be described later.

[2] The cement liquid 12 is injected into the depth range H corresponding to the framing pillar 7 in the pile hole 8, and the lower end portion of the framing column 6 is inserted into the upper end portion of the injection range to maintain the position. In this state, integration is attempted (see FIG. 3).

[3] When the installation of the corresponding structural support pillars 7 and the structural support pillars 6 is completed and each of them can secure a supporting force, the first floor beam 2 and the floor slab 3 are formed, and the structural support Integration with the head of the column 6 is performed, and the load is supported on the construction column 6.
Further, the beam 2 on the first floor has both ends abutted against the opposing earth retaining wall 5 and is installed so as to function as a cut beam (see FIG. 4).

[4] Subsequently, the construction of the ground part B1 and the underground part B0 is performed in parallel.
In the above-ground part B1, the column 1 and the beam 2 are sequentially formed in a state where a load is applied to the installed true pillar 6, and the construction is advanced to the upper floor.
In the underground part B0, ground excavation in a predetermined depth range is performed to form the beam 2 of the corresponding underground floor and to be integrated with the structural pillar 6. Similarly to the case of the first floor, the beam 2 of the corresponding underground floor is configured so that the end portion is brought into contact with the earth retaining wall 5 and functions as a cut beam (see FIG. 4).
It is to be noted that the column 1 and the beam 2 are formed in advance, and the construction of the floor slab 3 is postponed, so that the load on the middle of the construction column 6 and the construction platform column 7 can be applied to the floor slab 3. It can be reduced by the amount corresponding to the load.

[5] Further, the excavation on the lower floor side is advanced, and the construction pillar 6 on the immediately upper floor is reinforced and updated as the main pillar 1 (see FIG. 5). Thereafter, the underground excavation and the renewal of the structural pillar 6 to the main pillar are repeated.

[6] Excavation is performed up to the lowest layer, and the base portion K is formed in a state where the load can be supported. At this point, the entire design load can be supported by the foundation portion K, and the role as a support structure is transferred from the structural stand column 7 which has supported the load as a temporary structure to the foundation portion K.
Therefore, construction of each floor slab 3 of the underground part B0 and the above-ground part B1 which has not been formed is started with the construction of the pillar 1 and the beam 2 (see FIG. 6).
As for the wall 4 of each level, the outer peripheral part is preferably formed together with the construction of the pillar 1 and the beam 2 because the purpose of shielding from the outside is preceded, but the inner wall is a temporary construction stand pillar. In order to reduce the load on 7, it is preferable to delay until the construction time of the floor slab 3.
As described above, the building B is completed by completing the construction up to the top floor of the ground portion B1.

Next, the detailed installation method of the construction stem pillar 7 and the construction pillar 6 will be described.
[A] The guide casing 10 is installed up to an intermediate depth of excavation depth, and the inner space thereof is excavated by an excavator (not shown) of the type that excavates by rotating the auger 11 (see FIG. 7A). ).
For the excavation, it is preferable not to use industrial liquids, for example, it is preferable to carry out the excavation by using a moat only by rotating the auger 11 or a method of digging while discharging water from the tip.

[B] When excavation is completed up to the lower end depth of the structural support column 7, the auger 11 is rotated and the cement liquid 12 is discharged from the tip while being raised. A range in which the cement liquid 12 is discharged is set to a depth range H corresponding to the stem column 7 (see FIG. 7B).

[C] When the discharge of the cement liquid 12 in the depth range H corresponding to the structural stand column 7 is completed, the cement liquid 12 is switched to the poorly mixed cement liquid 13 and the depth range J to the lower end of the guide casing 10 is changed. Is injected into the pile hole 8 (see FIG. 7C).
By this step, the hole wall stabilizing effect by the poorly blended cement liquid 13 can be exhibited with respect to the depth range J between the guide casing 10 and the cement liquid 12 injection range.
Incidentally, the cement liquid 12 is prepared, for example, with a mixture having a water cement ratio of about 60%, and the poorly mixed cement liquid 13 is prepared, for example, with a composition having a water cement ratio of about 800%.

[D] After removing the excavator, while the cement liquid 12 and the poorly mixed cement liquid 13 in the pile hole 8 are maintained in a flowable state, the frame column 6 is inserted into the pile hole 8; The lower end portion is inserted into the cement liquid 12 and cured integrally with the position maintained (see FIG. 7D).
Incidentally, for the structural pillar 6, for example, a steel material such as H-shaped steel is generally used. In addition, although explanation is omitted, the installation angle (vertical) and the installation depth are appropriately measured while the construction column 6 is set up.

[E] The guide casing 10 is pulled out and the pile hole 8 is backfilled with soil (see FIG. 7E).
Through the above steps, the pedestal column 7 and the structuring column 6 can be installed.

According to the building construction method according to this embodiment, pile hole excavation can be carried out efficiently with simple construction equipment, and industrial waste treatment such as stable liquid accompanying excavation of the pile hole 8 does not occur. Costs can be reduced, and furthermore, since the cement liquid 12 with high cost merit can be used for the gantry column 7, the overall cost for building construction can be reduced.
In other words, by devising the construction procedure, it is possible to proceed with the reverse driving method while reducing the load acting on the structural stand column 7, and promoting simplification and small diameter drilling of pile holes and reduction of pile strength By doing so, it became possible to improve the economic efficiency of the entire building.

[Another embodiment]
Other embodiments will be described below.

<1> The building B described in the previous embodiment is merely an example, and the structure type, scale, and the like can be set as appropriate.

<2> The excavation of the pile hole 8 is not limited to being performed by the excavator using the auger described in the previous embodiment, and may be performed by an excavator of a different type.
Moreover, when excavating the pile hole 8, it is also possible to employ a method in which water is ejected in addition to performing by excavation.
In short, what is necessary is just by the pile hole excavation method which does not use a stabilizer.

<3> The cement liquid 12 and the poorly mixed cement liquid 13 are not limited to those described in the previous embodiment, and can be appropriately changed.
Moreover, even if it is the method of backfilling the soil in the pile hole 8 above it after inject | pouring the cement liquid 12 to the depth range H of the construction stand pillar 7 without using the poor mixing | blending cement liquid 13. Good.
Further, even when the poorly mixed cement liquid 13 is used, the hole wall stability of the pile hole 8 is not limited to being injected between the lower end portion of the guide casing 10 and the upper end portion of the depth range H of the frame column 7. It is also possible to reduce the injection to a minimum depth range that can be achieved.
Further, instead of injecting the poorly blended cement liquid above the gantry column 7, a method may be adopted in which the lower end portion of the guide casing 10 is installed deeply so as to reach the vicinity of the upper end of the gantry column 7. In this case, since the trouble of injecting the poorly blended cement liquid and the material itself can be omitted, the economy can be further improved.

<4> In the previous embodiment, the structural stand pillar 7 has been described as a temporary pile until the foundation K is completed, but is not limited to temporary construction. For example, the foundation pillar 7 includes the foundation K and the construction stand pillar 7. It may be designed to support building loads.

  In addition, as mentioned above, although the code | symbol was written in order to make contrast with drawing convenient, this invention is not limited to the structure of an accompanying drawing by this entry. In addition, it goes without saying that the present invention can be carried out in various modes without departing from the gist of the present invention.

1 pillar 2 beam 3 floor slab 6 construction column 7 construction platform pillar 8 pile hole 10 guide casing 12 cement liquid 13 poor blending cement liquid H depth range K foundation

Claims (5)

It is a building construction method that uses the reverse hammering method,
Drilling pile holes by a pile hole drilling method that does not use a stabilizing liquid,
Cement liquid is injected into the depth range to be the pedestal column in the pile hole, and the lower end portion of the pedestal column is inserted into the upper end portion of the cement liquid injection range to achieve integration,
A building construction method for building a building frame. Along with the construction of the building frame, the construction of columns and beams is performed in advance,
The building construction method according to claim 1, wherein construction of the floor slab is started after the foundation is completed. The foundation is a direct foundation;
The building construction method according to claim 2, wherein the structural stem pillar is a temporary pile. After injection of the cement liquid into the pile hole,
The building construction method according to any one of claims 1 to 3, wherein a poorly blended cement liquid that is poorer than the cement liquid is poured into an upper range of the pouring range to stabilize the hole wall of the pile hole. In the formation of the stem frame, a guide casing is installed in a state where the lower end is located near the upper part of the cement liquid injection range,
Between the lower end part of the said guide casing and the upper end part of the injection | pouring range of the said cement liquid, the poor mixing | blending poor cement liquid is injected from the said cement liquid, and the hole wall stability of the said pile hole is aimed at. 4. The building construction method according to any one of 3 above.

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