JPH11117323A - Construction method of foundation structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the workability by leaving at least one underground beam and constructing other underground beams and footings, and thereafter constructing the remaining underground beams lastly. SOLUTION: A footing 5a and an underground beam 8a, the following footing 5b and underground beam 8b, and the subsequent footing 5c and underground beam 8c are constructed in sequence. In this construction way, concrete mixer- vehicles can freely come and go through the openings between the footings 5d, 5e and the footings 5e, 5f and hence, concrete can be easily placed in the forms of the footings 5a, 5b, 5c. Then, the underground beams 8a, 8b, 8c are made of precast beams for instance and the openings are excavated after construction of these beams and precast beams 8d, 8e are installed and the footings 5d, 5e, 5f of both ends are formed. And then, the same execution is repeated. In this way, the foundation work can be easily and rapidly carried out and the filling-back work can be rapidly carried out in the case of the precast beams. Accordingly, the construction period can be shortened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of constructing a foundation structure serving as a foundation of a building.

[0002]

2. Description of the Related Art Conventionally, as shown in FIGS. 7 to 9, a foundation structure of a building is formed by excavating a ground surface 1 into a substantially inverted truncated cone shape to form a footing excavation portion 2. Ground 3
Is provided with a footing 5 directly or via a lap concrete 4. The footing 5 is composed of a base portion 6 and a column portion 7, and a plurality of the footings 5 are arranged vertically and horizontally as shown in FIG. In order to form a footing excavation part 2 and an underground beam 8 by bridging and integrating,
Is formed as a basic structure by backfilling the underground beam excavation portion 11 having an inverted trapezoidal cross-section provided in.

[0003] Both the footing 5 and the underground beam 8 are
A reinforcing steel is integrated therein, and the reinforcing steel inside the footing 5 and the reinforcing steel inside the underground beam 8 are integrated by welding. In forming the footing 5 and the underground beam 8, after arranging reinforcing steel therein, concrete is poured into the inside of the formwork to complete the footing 5 and the underground beam 8. . A slab is usually provided on the underground beam 8 and the footing 5, and a column of a building is to be built on the column 7 of the footing 5.

[0004]

However, in the prior art, as shown in FIG. 9, the excavating section 2 for footing and the excavating section 11 for underground beams are excavated first and arranged in a construction, and then the formwork is set. Then, concrete is cast and the footing 5 and the underground beam 8 are formed. According to this, a closed loop L surrounded by the excavated portions 2 and 11 is formed. Since the concrete mixer truck cannot be carried into the inside, the concrete placing of the footing 5 and the underground beam 8 needs to be performed from outside the closed loop L. However, concrete can be cast relatively easily on the footing and the underground beam located on the outside.
As for the W and the underground beam 8W, the hose must be extended from the concrete mixer truck, and concrete must be sent into the inside of the construction site by this hose and must be cast by hand. There was a disadvantage that the work period was long.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to eliminate the above-mentioned drawbacks by allowing a concrete mixer truck or heavy equipment to enter a region to be surrounded by a footing and an underground beam. It is.

[0006]

According to the first aspect of the present invention, at least one underground beam is left and footing is performed so that a closed loop due to the underground beam and footing does not occur. After that, the remaining underground beams are constructed last, so that the concrete mixer truck can freely enter and exit before the remaining underground beams are constructed.

[0007] The invention according to claim 2 is to use precast as an underground beam, so that backfill of earth and sand can be performed at an early stage.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. FIGS. 1 to 6 are views showing an embodiment of a method for constructing a foundation structure according to the present invention. In each of the drawings, the same reference numerals are used for the same components as those in FIGS. In the present invention, as shown in FIGS. 1 and 2, when the foundation structure is constructed, one footing 5a located at a corner of the footing arranged in a vertical and horizontal arrangement is used as a starting point. The adjacent footing and underground beam are sequentially constructed so as to sequentially draw an S-shape. Specifically, when the footing 5a and the underground beams 8a, 8a connected to the footing 5a are completed, the next footing 5b and the underground beams 8b, 8b connected to the footing 5b are constructed, and then, Next, the footing 5c and the underground beam 8c will be constructed.

According to this construction method, the space between the footing 5d and the footing 5e and the space between the footing 5e and the footing 5f are in an open state. Can be carried in, and concrete can be easily poured into a mold for forming the footings 5a, 5b, 5c.

In this embodiment, the underground beams 8a, 8b, 8
About c, what was manufactured beforehand in a factory etc., ie, a precast is used, and after transporting this precast to a construction site, after installing it in the underground beam excavation part 11, immediately backfill it. Is what you do. The installation of the precast is performed by using a heavy machine and carrying the heavy machine from the open portion Q.

After the foundation structure is constructed with the part Q open as described above, the open part Q is excavated and the precast underground beam 8d, as shown in FIG.
8e, and the footings 5d, 5e, 5f at both ends of the underground beams 8d, 8e are formed. By repeating such forming, that is, the footing and the underground beams are formed in a meandering state. To complete the basic structure.

Next, the formation of the footing and the integration of both ends of the underground beam into the footing, which are made by precasting, will be described with reference to FIGS. First, a marking for footing called "inking out" and positioning of an underground beam are added to the ground surface. In this case, for the underground beam 8, a precast previously produced in a factory or the like is used. As shown in FIG. 3, the footing site where the above-mentioned summing was performed was excavated as shown in FIG. 3 to form an inverted frustum-shaped excavated portion 2 for footing. A ring-shaped sediment stop plate 9 is provided around the outer periphery of the portion to be formed.
Upright. A reinforcement member (not shown) is provided on the earth and sand stopper 9 so as not to fall inward, and a ladder is installed so as to be able to enter and exit the interior. Next, the sediment 1a deposited on the surface 1 at the time of excavation in the space outside the sediment stop plate 9
And backfill.

FIG. 4 shows a state in which the backfilled earth and sand 1b thus backfilled is deposited on the outer portion of the earth and sand stopper plate 9. Reinforcing bars 5 for footing are arranged inside the earth and sand stopper plate 9, and a formwork 10 for footing is provided.

In addition, the ground surface 1 is excavated corresponding to the installation location of the underground beam to be connected to the footing, and the underground beam excavating portion 11 is formed.
, And then the earth and sand stopper plate 9 corresponding to the underground beam
Is cut into a U-shape to provide a cut portion 12, where an underground beam can be installed.

Next, as shown in FIG. 5, the underground beam 8 is set inside the underground beam excavation section 11 and the cut section 12,
The underground beam main reinforcement 8M protruding from the tip of the underground beam 8 is positioned at a position approaching the reinforcing bar 5M. Next, after the underground beam excavation portion 11 is backfilled with backfilled soil 8K previously deposited on the surface of the ground, the underground beam main reinforcement 8M and the column reinforcing bar projecting upward from the formwork 10 are welded. Then, after arranging the connecting portions, concrete footing is formed by casting concrete inside the formwork 10. In this case, since the backfill soil 1b is present, the concrete mixer truck can be relatively easily brought close to the space where the formwork 10 is installed, so that concrete can be easily poured. The concrete mixer truck can be carried into the construction site via the open part Q described above. After the concrete is cast, the formwork 10 is removed and the inside surrounded by the sediment stop plate 9 is further filled with external earth and sand to backfill, thereby completing one footing and the construction of an underground beam connected to this. I do.

As shown in FIG. 1 by using the steps shown in FIGS. 3 to 6, first, a sediment stop plate 9a is installed to provide a footing 5a and underground beams 8a, 8a.
In the present embodiment, when the footing excavation part 2a is formed, the underground beam 8 to which the footing 5a is connected is formed.
The footing excavations 2b and 2f for forming the footings 5b and 5f on the other end side of the a and 8a are also formed in advance by excavation, and sediment stop plates 9b and 9f are provided here. , 9f is filled with the sediment 1a, and the U-shaped cut portion 12 is provided at the upper end of the sediment stop plates 9b, 9f, so that the underground beams 8a, 8a can be installed without any obstacle. , Can be installed horizontally in the underground beam excavation sections 11a, 11a provided in advance. Next, the footing 5b and the underground beams 8b, 8
In the construction of b, excavation parts 11b, 11b for installing the underground beams 8b, 8b are provided, and footing excavation parts 2c, 2e on the other end side of the underground beams 8b, 8b are also provided. A U-shaped cut portion 12 is provided at the upper end of the sediment stop plates 9c and 9e in the excavated portions 2c and 2e, and in this state, precast underground beams 8b and 8b are carried in from outside and installed. After backfilling the underground beams 8b, 8b,
The concrete for the footing 5b may be cast in the same manner as in the above-described process.

Next, when forming the footing 5c,
An underground beam excavation portion 11c for the underground beam 8c is provided. An excavation portion 2d for forming a footing 5d at the other end of the underground beam 8c is provided, and the underground beam is excavated similarly to the above-described process. The footing 5c can be formed by setting the center beam 8c and placing concrete in the formwork in the footing excavation part 2c.

Next, as shown in FIG. 2, the underground beam 8d is bridged to the excavated portion 2d, and the excavated portion 2i is provided, and the underground beam 8d is bridged therebetween, and the footing 5d is connected. It is formed by casting concrete, and then excavated for footing 2
The footing 5e, 5f is completed by bridging the underground beam 8e between e and 2f, and bridging the underground beam 8e between the footing excavations 2e, 2h and placing concrete. . The footing is sequentially formed in such a meandering state.

According to the present embodiment, as shown in FIG. 1, the space surrounded by the footings 5a and 5b and the underground beams 8a and 8b does not form a closed loop but is partially open, so that the footing is formed. Excavation part 2a, underground beam excavation part 11
Since the excavation operations a and 11a can be performed from the inside of the construction site, the excavation operation can be performed quickly. Further, since the concrete mixer truck can enter the inside of the construction site through the opened portion Q, concrete can be easily poured into the excavating portions 2e and 2h for the footing located at the center side thereof, for example. As in the related art, the troublesome work of laying a hose from outside the construction site and placing concrete can be omitted, the burden on the operator can be reduced, and the construction period can be shortened. In addition, since heavy equipment can enter the inside of the construction site, the precast underground beam can be easily carried into the specified place from the inside and installed.There is no problem with using the precast underground beam. Does not occur.

The present embodiment has the following effects. Conventionally, when performing construction on a narrow site, there is no place to temporarily store the excavated earth and sand.Therefore, in general, transport by truck to another place away from the construction site and dispose of it by truck become. Therefore, when performing backfilling after building the frame, it is necessary to purchase new earthfill for backfilling, which requires not only disposal costs but also purchasing costs, which leads to an increase in construction costs. Was. However, according to the present embodiment, the space required for forming the footing is immediately rebuilt around the sediment retaining plate, leaving a necessary space for forming the footing, and the early backfilling is performed by using a precast underground beam. It is possible. Therefore, it is possible to contribute to a reduction in costs related to off-site disposal (transportation disposal cost and cost of purchased earth and sand).

Further, according to the present embodiment, since the construction proceeds in order along the S-shape, the concrete mixer truck, heavy equipment and the like can be carried to the construction site, so that concrete can be efficiently poured. In this way, early backfill of excavated earth and sand and installation of precast underground beams are possible.

In this embodiment, the following effects are obtained by using the precast underground beams. That is,
When performing construction on a narrow site, the excavation site is an operation that is close to the adjacent land. For this purpose, it is common to provide a landscaping near the site boundary line in a place close to the site, but as in the present embodiment, provide a sand stopper on the foundation and backfill it early, After excavation, the precast underground beam is set and then backfilled at an early stage. Therefore, even when a mountain stay is to be provided in the vicinity, a small mountain stay can be used, and in some cases, the mountain stay itself can be omitted.

[0023]

According to the present invention, at least one underground beam is left and footing is applied to another underground beam so that a closed loop due to the underground beam and footing does not occur. Since the center beam is constructed last, a concrete mixer truck etc. can easily enter the inside of the construction site. it can.

According to the second aspect of the present invention, the underground beam is integrated with the footing using the precast, so that the precast excavation portion for filling the precast can be quickly backfilled, This can also shorten the construction period.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of a method for constructing a foundation structure according to the present invention.

FIG. 2 is a plan view showing an embodiment of the present invention.

FIG. 3 is a sectional view showing one embodiment of the present invention.

FIG. 4 is a sectional view showing an embodiment of the present invention.

FIG. 5 is a sectional view showing an embodiment of the present invention.

FIG. 6 is a sectional view showing an embodiment of the present invention.

FIG. 7 is a perspective view showing a construction example of a conventional footing.

FIG. 8 is a cross-sectional view showing a construction example of a conventional footing and underground beam.

FIG. 9 is a plan view showing an example of construction of a conventional footing and underground beam.

[Explanation of symbols]

1 ground, 1a sediment, 2 footing excavation,
3 Ground, 4 Rapple concrete, 5M steel bars, 6
Base part, 7 pillar part, 8 underground beam, 9 earth and sand stopper,
10 Formwork, 11 Underground beam excavation section, 12 Cut section.

Claims (2)

[Claims] 1. A method for constructing a foundation structure comprising underground beams bridging between vertical and horizontal footings, wherein at least one underground beam is provided so that a closed loop due to the underground beams and the footing does not occur. A footing with another underground beam, leaving the underground beam last, and then finally installing the remaining underground beam. 2. The footing according to claim 1, wherein the footing is formed by arranging a reinforcing bar and placing concrete in a formwork, and the underground beam is integrated with the footing by using a precast. Construction method of foundation structure.