JPH1193182A - Foundation structure and execution method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the term of works, and to reduce cost by simplifying the structure of a foundation. SOLUTION: In the foundation structure, a ground surface 4 is cut and crushed stone layers 5 are formed, and a peripheral supporting slab 1 is formed on the crushed stone layer 5 while a pressure-resisting plate 2 is shaped at the top section of the peripheral supporting slab 1 as being unified with the peripheral supporting slab. Foams 3 made of a synthetic resin are buried between the pressure-resisting plate 2 and the ground surface 4. The load of a building is transmitted from the pressure-resisting plate 2 and the foams 3 to the ground surface 4. In the execution method, forms 6 are installed on the crushed stone layer 5 while the foams 3 are arranged at internal specified places surrounded by the forms 6, PC steel bars 7 (sheaths 12) are disposed to the upper sections of the foams 3 at regular pitches, and concrete is placed into a space composed of the forms 6 and the foams 3, thus constructing a foundation. Concrete is solidified, and tension is applied to the PC steel bars 7 (the PC steel bars 7 inserted into the sheaths 12) and compressive stress is worked to the pressure-resisting plate 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a base structure of a relatively light wooden or steel-framed building or a residential building, and more particularly to a base structure in which a base pressure plate can also serve as a floor on the first floor. , Its construction method.

[0002]

2. Description of the Related Art Even in a relatively light building made of wood or steel, a foundation corresponding to the strength of the ground is constructed, and a skeleton is assembled on the foundation. An example of a foundation adopted for such a building will be described with reference to FIGS.

FIG. 4 shows a solid foundation, which is applied to a building having a relatively large weight. In this solid foundation structure, the ground 51 is excavated to a predetermined depth in accordance with the plan of the building to form a crushed stone layer 52, and after arranging reinforcement on the upper surface of the crushed stone layer 52, concrete is poured and the weight of the building is reduced. The base bottom plate 53 (pressure-resistant plate) for dispersing the steel on the ground is formed, and the base beam 54 is erected from the base bottom plate 53.
Then, for example, a concrete panel is placed on the upper end surface of the foundation beam 54 to form the floor 55 on the first floor.

As described above, in the solid foundation, the foundation bottom plate 53 is made of reinforced concrete, and a predetermined number of reinforcing bars are arranged to cope with the ground reaction force, and concrete having a thickness of about 200 mm to 300 mm is cast. General.

FIG. 5 shows a cloth foundation, which is applied to a building whose weight is relatively small. In this cloth foundation structure, a crushed stone layer 52 is formed by cutting off a position set according to a building plan of the ground 51, and a footing for dispersing the weight of the building to the ground on the upper surface of the crushed stone layer 52. By forming the foundations 54 by connecting the footings 56 together with the footings 56, the desired foundation is formed. Also foundation beams
A moisture-proof film 57 is laid on the surface of the ground 51 surrounded by 54, and a holding mortar 58 is cast on the moisture-proof film 57. Then, for example, a concrete panel is placed on the upper end surface of the foundation beam 54 to form the floor 55 on the first floor.

[0006] When the ground surface is exposed below the floor 55 on the cloth foundation as described above, water vapor and moisture may rise from the ground surface and impair the habitability. A film 57 is laid.

[0007]

In the solid foundation described above, it is necessary to excavate the entire ground surface on which the foundation is to be constructed, and a large amount of residual soil is generated. For this reason, there is a problem that much cost is required for the treatment of the residual soil.

In the above-mentioned cloth foundation, a moisture-proof film is laid on the ground surface to block moisture from under the floor,
Further, it is necessary to perform work such as placing a holding mortar on the moisture-proof film, and there is a problem that a long construction period is required and there is a limit in reducing the cost.

Further, in each of the above-mentioned foundations, it is necessary to install a formwork on both sides along a target foundation beam in order to form a foundation beam, and work such as installation and removal of the formwork is indispensable. Become. For this reason, there is a problem that there is a limit in shortening the construction period.

[0010] An object of the present invention is to provide a foundation structure capable of reducing the amount of residual soil generated, securing moisture resistance, and shortening the construction period, and a method of constructing the foundation structure.

[0011]

According to the present invention, there is provided a foundation structure according to the present invention, wherein a pressure plate of the foundation also serves as a floor on the first floor, and a synthetic resin is provided between the pressure plate and the ground surface. It is characterized in that the foam is buried.

In the above basic structure, since the pressure plate of the foundation also serves as the floor of the first floor, and the synthetic resin foam is buried between the pressure plate and the ground surface, the base plate and the floor of the solid foundation structure are used. There is no need to configure both, and the construction period can be shortened. Since the space between the pressure plate and the ground surface is filled with a synthetic resin foam, the load of the building acting on the pressure plate can be transmitted to the ground surface via the foam.
Therefore, the load can be supported substantially in the same manner as the solid foundation structure.

In the above basic structure, it is preferable that stress is applied to the pressure plate. Thus, by applying stress to the foundation pressure plate, this pressure plate becomes prestressed concrete and can exhibit high tensile strength and bending strength. For this reason, the thickness of the pressure-resistant plate can be reduced as compared with the bottom plate of the solid basic structure.

[0014] Further, the method for constructing a foundation structure according to the present invention comprises the steps of disposing a synthetic resin foam at a predetermined position on the ground surface and arranging a form along the foam to form the foam and the mold. It is characterized in that concrete is poured into a space defined by the frame and a foundation on which a pressure plate is arranged on the upper surface of the foam is formed.

In the above construction method, a foam of synthetic resin is arranged on the ground surface and a mold is provided around the foam, so that the side and top surfaces of the foam are used as a mold when forming a foundation. Can be used. Then, the foam is buried and killed by pouring concrete into a portion surrounded by the formwork, thereby making it possible to form a pressure-resistant plate which also serves as the floor of the first floor.

In particular, in a building having a small weight, a cloth foundation structure is generally adopted. However, the ground reaction force is reduced by using a solid foundation structure capable of expecting a ground reaction force on the entire surface of the building. Thus, even if the foam is buried between the pressure plate and the ground surface, the ground reaction force can be borne. Further, the moisture buried under the floor can block moisture from the ground surface.

In the above-mentioned construction method, the high-strength steel itself or a pipe for inserting the high-strength steel is arranged at a preset position corresponding to the pressure plate, and after the poured concrete is solidified. Preferably, tension is applied to the pre-placed high-strength steel or the high-strength steel inserted into the pipe to generate stress in the pressure-resistant plate. With the foundation structure constructed by this construction method, the strength of the pressure plate can be improved.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the above-described basic structure and a construction method for realizing the basic structure will be described below with reference to the drawings. 1 is a sectional view illustrating a basic structure according to a first embodiment, FIG. 2 is a plan view illustrating a basic structure according to a second embodiment, and FIG. 3 is a partial cross section illustrating a basic structure according to a second embodiment. FIG.

The basic structure shown in FIG. 1 is applied to a building having a small scale. An outer peripheral supporting plate 1 is formed corresponding to a plan configuration of a target building. A pressure plate 2 is formed on the top and integrally with the outer peripheral support plate 1. A synthetic resin foam 3 is disposed below the pressure plate 2 and between the ground surface 4 and the pressure plate 2.

The outer peripheral support plate 1 easily cuts the ground surface 4 and is formed above a crushed stone layer 5 provided at the cut portion. That is, the outer peripheral support plate 1 is defined by a mold 6 whose outer surface is provided above the crushed stone layer 5, and is formed to have a predetermined thickness and height including a reinforcing bar (not shown).

The pressure-resistant plate 2 is formed integrally with the outer peripheral support plate 1 on the top of the outer peripheral support plate 1 so as to be able to double as the floor of the first floor in the building. That is,
The pressure plate 2 has a reinforcing bar (not shown) connected to the reinforcing bar of the outer peripheral support plate 1, and is formed so that the top end surface is equal to the floor level of the first floor.

In the case where stress is applied to the pressure plate 2, in the present embodiment, the PC steel bar 7 such as a PC steel wire or a PC steel bar which becomes high-strength steel at a predetermined pitch in the plane of the pressure plate 2 is arranged. After the concrete constituting the pressure plate 2 is solidified and exhibits a predetermined strength, a tension is applied to the PC steel rod 7 by the PC steel rod tensioning jig 8 so that the compressive stress is applied to the pressure plate 2. Can be applied.

The foam 3 is disposed between the pressure plate 2 and the ground surface 4, and the side surface functions as a forming frame of the outer peripheral support plate 1 together with the mold frame 6, and the upper surface functions as a forming frame of the pressure plate 2. I do. Further, the foam body 3 is located between the pressure plate 2 and the ground surface 4 and has a function of transmitting a load acting on the pressure plate 2 to the ground surface 4.

As the foam 3 having the above function, any foam having a compressive strength enough to support the load of the building and having a waterproof property can be used. In particular, the compressive strength, including the safety factor, ranges from 0.1 kg to 1 kg per square centimeter, preferably from 0.5 kg to 1 kg.
The range is 1 kg.

Examples of the foam 3 that can be used include foamed polystyrene and foamed polyethylene.
The dimensions of the foam 3 are not particularly limited. That is, one foam 3 having a size suitable for forming the target base may be molded and used, or a foam 3 of a standard size may be molded and used. It may be selectively used according to the basis.

In the basic structure constructed as described above, the pressure plate 2 also serves as the floor of the first floor, and the foam 3 disposed between the lower surface of the pressure plate 2 and the ground surface acts on the pressure plate 2. Can be transmitted to the ground.

Next, a construction method for constructing the above-mentioned foundation structure will be described. First, the ground surface 4 is easily cut along the peripheral support plate 1 on the target foundation, and a crushed stone layer 5 is formed at the cut portion. That is, the outer periphery supporting plate 1 is formed on the outer periphery of the foundation structure like the conventional cloth foundation, but does not require footing. Also, unlike the solid foundation structure, there is no need to excavate the entire surface. Therefore, it is only necessary to make a shallow and simple root cutting on the ground surface 4, and the construction becomes easy.

Next, a mold 6 that defines the outer surface of the outer peripheral support plate 1 and the outer surface of the pressure-resistant plate 2 is installed on the crushed stone layer 5. The foam body 3 is arranged at a predetermined distance from the mold frame 6 of FIG. For this operation, the foams 3 need only be arranged on the ground surface 4.

The form 6 and the foam 3 above the crushed stone layer 5
A reinforcing bar for the outer peripheral support plate 1 is arranged in a space surrounded by the above, and further, a reinforcing bar for the pressure plate 2 is arranged on the upper surface of the foam 3. At this time, by arranging the PC steel rods 7 with the PC steel rod tensioning jigs 8 attached to both ends thereof on the upper surface of the foam body 3 together with the reinforcing bars at a predetermined pitch and lengthwise and widthwise, the stress on the pressure-resistant plate 2 in a later step. Can be provided.

After arranging the foam 3, the form 6, the reinforcing bar and the PC steel bar 7 as described above, concrete is poured into the space defined by the foam 3 and the form 6 to support the outer periphery. The plate 1 and the pressure-resistant plate 2 can be integrally formed. At this time, the foam 3 is buried and killed in the space formed by the perimeter support plate 1 and the pressure plate 2 formed by the cast concrete.

As described above, since the foam 3 exhibits a function as a mold for forming the outer peripheral support plate 1 and the pressure plate 2, the cast concrete is brought into close contact with the foam 3 and integrated therewith. . Therefore, when an out-of-plane force acts on the pressure plate 2, the force is transmitted from the pressure plate 2 to the foam 3, and further transmitted to the ground surface 4 via the foam 3.

After the poured concrete has solidified, the foundation is constructed by removing the formwork 6. Further, after removing the mold frame 6, it is possible to apply a compressive stress to the pressure-resistant plate 2 by operating the PC steel bar tension jig 8 to apply tension to the PC steel bar 7.

The pressure plate 2 to which the compressive stress acts acts as prestressed concrete, and can exhibit high strength against bending force acting on the pressure plate 2 due to the load of the building. Further, the foam 3 is disposed in close contact with the lower side of the pressure plate 2, and further, since the foam 3 is in close contact with the ground surface 4, the force acting on the pressure plate 2 is applied to the ground via the foam 3. It is possible to transmit to the surface 4.

As described above, since the pressure plate 2 is set at a position higher than the ground surface 4, the pressure plate 2 can also serve as the floor of the first floor of the building, and the load of the building acting on the floor can be reduced. It can be reasonably supported by the pressure plate 2 and the foam 3.

Next, a basic structure according to a second embodiment will be described with reference to FIGS. The foundation structure of this embodiment is adopted when the weight of a building is relatively large. In the drawings, the same portions and portions having the same functions as those of the above-described embodiment are denoted by the same reference numerals, and description thereof will be omitted.

As shown in the figure, an outer foundation beam 10 arranged on the outer periphery and an inner foundation beam 11 arranged inside are arranged according to the first floor plan of the target building. Each of these foundation beams 10 and 11 is the same as the outer peripheral support plate 1 except that it is formed to be slightly thicker than the outer peripheral support plate 1 in the first embodiment.

In this embodiment, a sheath 12 serving as a tube for inserting the PC steel rod 7 is arranged above the foam 3 at the time of arranging the reinforcement, and the concrete is solidified to exhibit a predetermined strength. The PC steel rod 7 is inserted through the sheath 12 and
A tension is applied to the steel rod 7 by a PC steel rod tensioning jig 8, and this tension is transmitted to the pressure-resistant plate 2 via the sheath 12.
A compressive stress is applied to the pressure plate 2.

As described above, when a compressive stress is applied to the pressure plate 2, the force may be directly transmitted from the PC steel bar 7 to the concrete constituting the pressure plate 2. May be transmitted to the concrete constituting the pressure-resistant plate 2 via the sheath 12.

Also in this embodiment, the foam 3 is used as the foundation beam 1
Functions as molds of 0, 11 and the pressure plate 2 are the same as in the first embodiment. In particular, since the foam body 3 can be used as a mold for forming the internal foundation beam 11, the setup work when constructing the foundation becomes extremely easy.

Further, even in the basic structure of the present embodiment, the pressure-resistant plate 2 is located at a predetermined high position from the ground surface 4 and can also serve as the floor of the first floor of the building. The load of the building acting on the floor of the first floor can be rationally supported by the pressure plate 2 and the foam 3.

[0041]

As described above in detail, in the foundation structure according to the present invention, since the pressure plate also functions as the floor of the first floor, the foundation and the floor of the first floor can be constructed simultaneously. Therefore, the construction period can be shortened. Further, there is no need to excavate the entire area of the ground surface or excavating the area corresponding to the footing, and the excavation depth may be small. For this reason, the amount of the residual soil is reduced, and the processing cost can be reduced.

Also, by embedding the foam between the pressure plate and the ground surface to form a substantially solid foundation structure, the ground reaction force per unit area is reduced, and the foam is made of a synthetic resin foam having low strength. Even if there is, it can bear the ground reaction force.

By applying an in-plane stress to the pressure plate, even if a load of a building acts on the pressure plate, the load can be rationally supported and the thickness of the pressure plate can be reduced. I can do it.

By disposing a waterproof synthetic resin foam between the pressure plate and the ground surface, the load acting on the pressure plate can be transmitted to the ground surface via the foam,
In addition, moisture from the ground surface can be prevented. The foam can be used as a heat insulating material for the floor.

Further, in the construction method according to the present invention, the foam placed at a predetermined position surrounded by the formwork can be used as a formwork for the outer peripheral support plate or the foundation beam and the pressure plate. Since this foam is embedded in the cast concrete, there is no need to remove it even after the concrete has solidified. For this reason, the construction period of the foundation work can be significantly shortened and the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a basic structure according to a first embodiment.

FIG. 2 is a plan view illustrating a basic structure according to a second embodiment.

FIG. 3 is a partial sectional view illustrating a basic structure according to a second embodiment.

FIG. 4 is a diagram illustrating a conventional solid basic structure.

FIG. 5 is a view for explaining a conventional cloth foundation structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Perimeter support plate 2 Pressure plate 3 Foam 4 Ground surface 5 Crushed stone layer 6 Formwork 7 PC steel rod 8 PC steel rod tension jig 10 Peripheral foundation beam 11 Inner foundation beam 12 Sheath 51 Ground 52 Crushed stone layer 53 Foundation bottom plate 54 Foundation Beam 55 Floor 56 Footing 57 Moisture proof film 58 Holding mortar

Claims (5)

[Claims] 1. The pressure plate of the foundation also serves as the floor of the first floor,
A basic structure, wherein a synthetic resin foam is buried between the pressure plate and the ground surface. 2. The basic structure according to claim 1, wherein a stress is applied to the pressure plate. 3. A synthetic resin foam is placed at a predetermined position on the ground surface, and a form is arranged along the foam, and concrete is placed in a space defined by the foam and the form. A method of constructing a foundation structure, which comprises casting and forming a foundation on which a pressure plate is arranged on an upper surface of a foam. 4. A high-strength steel is arranged at a preset position corresponding to the pressure plate, and after the cast concrete is solidified, a tension is applied to the high-strength steel to apply a stress to the pressure plate. The method for constructing a foundation structure according to claim 3, wherein the method is applied. 5. A pipe for inserting high-strength steel at a preset position corresponding to the pressure plate, and after the cast concrete is solidified, insert the high-strength steel into the pipe and The method according to claim 3, wherein a tension is applied to the high-strength steel to apply a stress to the pressure plate.