JP2002227256A - Concrete water tank and its constructing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To construct a concrete water tank of superior quality in a narrow area. SOLUTION: When a constructing hole D is excavated, corrugated plates 2a are joined mutually by bolts 8 in conformity with the progress of excavation by an inverted construction method, and outer forms 2 are assembled into the constructing hole D. High superplasticized concrete is injected among inner forms 3 and bottom forms 1 and the outer forms 2 from an injection pipe 11 and solidified, and a concrete bottom slab A and a concrete peripheral wall B are built integrally. Accordingly, an inverted construction method, which does not take space, is enabled because the outer forms 2 having a large shape has a structure in which a large number of the corrugated plates 2a are joined and assembled, and the concrete water tank T of superior quality can be built without trouble even in the narrow area in which a car and heavy machinery for execution cannot be used because each corrugated plate 2a can be carried by human power.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a concrete water tank which can be easily constructed in a narrow area and a method of constructing the same.

[0002]

2. Description of the Related Art Cast-in-place water tanks and precast water tanks are known as concrete water structures.

[0003] The cast-in-water tank is used to transport all materials to the site, assemble a formwork, pour ready-mixed concrete into the space, and wait for solidification to complete the construction. Since the construction material can be divided into small and lightweight components, it can be transported and constructed anywhere by human power.

[0004] In the precast water tank, each part of the concrete water tank is produced in a factory so as to be freely assembled, and is transported to the site to be assembled. This precast tank
Since the main parts are factory-manufactured, high-quality water tanks can be constructed in a short period of time.

[0005]

However, since the on-site water tank is all work on site, it is susceptible to the weather, is inferior in quality reliability, and has a problem that the construction period is likely to be long. is there.

In the precast water tank, each part of the water tank produced in the factory is large and heavy, a vehicle is indispensable for transporting the tank, and heavy equipment is required for assembling at the site. There is a problem that it cannot be built.

The present invention provides a concrete water tank capable of constructing a high-quality concrete water tank in a narrow area in a short period of time, and a method of constructing the concrete water tank, by making use of the advantages of the above-mentioned cast-in-place method and precast method as they are, and compensating for the disadvantages. The purpose is to: Another object of the present invention is to provide a concrete water tank and a method for constructing the same, which can reduce costs.

[0008]

In order to achieve at least one of the above-mentioned objects, the present invention is directed to a concrete water tank in which a concrete peripheral wall is integrally connected to a concrete bottom slab. The outer mold was formed by joining a number of corrugated plates.

According to this means, a large number of corrugated plates constituting the outer formwork are processed in advance in a factory so that the outer formwork can be easily assembled by being manually brought to the site, and a concrete tank is to be constructed. When drilling a construction hole in the ground,
In conjunction with the excavation of the construction hole, joining is sequentially performed by a so-called reverse winding method, and an outer formwork is assembled in the construction hole. Then, the inner formwork is assembled, and ready-mixed concrete is poured between the outer formwork and the inner formwork to construct a concrete tank. The outer formwork is left underground as a discarded formwork.

[0010] As described above, since the outer frame, which is a main component of the concrete water tank, is constructed by joining a number of corrugated plates, each corrugated plate can be carried manually and assembled easily. Factory can be produced. Therefore, it is possible to construct a concrete tank in a narrow area. Further, the corrugated plate has a high strength and is hardly deformed due to collapse of earth and sand which is likely to occur when excavating a construction hole, and thus is useful for constructing a concrete tank having a predetermined shape and strength.

In the concrete water tank according to the first aspect, it is preferable that a bottom formwork is provided below the concrete bottom slab, and the concrete bottom slab and the peripheral wall of the concrete are made of high-fluidity concrete. In this configuration, the bottom formwork prevents the infiltration of high flow concrete into the ground. In addition, the high-fluidity concrete flows smoothly and solidifies between the inner formwork, the outer formwork and the bottom formwork without any gap, so that a concrete water tank of higher quality is obtained.

According to a third aspect of the present invention, there is provided a step of joining a plurality of veneers and incorporating an outer formwork into the construction hole while excavating the construction hole at the site where the concrete tank is to be constructed. The method includes a step of assembling the inner formwork inside the outer formwork, and a step of casting and solidifying ready-mixed concrete between the inner formwork and the bottom and the outer formwork.

In this means, the outer formwork is assembled in the construction hole by joining the veneers in accordance with the progress of excavation of the construction hole by the reverse winding method, so that the excavation of the construction hole and the assembly of the outer formwork are performed. Unlike the general open-cutting method, which is performed in a separate process, the construction of a concrete tank in a narrow area is easy without taking up space. The joining of the veneers is usually a flange joining in which a flange provided on the veneer is joined with a bolt and a nut, but other joining such as welding can be adopted.

[0014] In the method for constructing a concrete tank according to the third aspect, a step of laying a bottom formwork at the bottom of the construction hole is provided, so that the ready-mixed concrete can be made into high-fluid concrete. In this configuration, the infiltration of the high-fluidity concrete into the ground is prevented by the bottom mold, while the high-fluidity concrete flows and solidifies between the inner mold, the outer mold, and the bottom mold. Therefore, a high quality concrete water tank can be constructed without wasting high fluidity concrete.

[0015] In the method for constructing a concrete water tank according to claim 4, it is preferable that the bottom mold has an inverted shape. In this configuration, the concrete volume is reduced and the cost is reduced.

In the method for constructing a concrete water tank according to any one of claims 3 to 5, it is preferred that the veneer of the outer formwork is a corrugated plate (claim 6). With this configuration, the corrugated board is strong and hardly deformed or damaged by the collapse of earth and sand that is likely to occur with the reverse winding method,
A concrete tank with the shape and strength as designed can be constructed.

[0017]

Embodiments of the present invention will be described with reference to the accompanying drawings. 1 to 4 show an embodiment of the present invention. The concrete tank T according to the present invention includes a concrete bottom slab A, a concrete peripheral wall B, and a concrete lid slab C, which are constructed by a bottom form 1, an outer form 2, an inner form 3, and a lid form 4. .

The bottom mold 1 is made of fiber reinforced plastic (FR
P) or an invert shape made of a plate material, and is laid on the cobblestone 6 spread on the bottom of the construction hole D.

The outer frame 2 is made up of a large number of corrugated plates (single plates)
The bolts 8 are inserted through the through-holes 2c of the flanges 2b provided on the flanges 2a, and the nuts 9 are screwed into the bolts 2a to integrally join them. Each corrugated board 2
a is factory-produced to a size and weight that can be freely carried by a person.

The inner form 3 is made of a plate material or the like, and the bottom form 1
A concrete casting space is formed inside the outer mold frame 2 and fixed by a separator (not shown) or the like as is well known. On the bottom surface of the inner mold 3, a ready-mixed concrete injection pipe 11 and an air release pipe 12 are provided.

The lid form 4 is made of a precast plate, steel, or the like, and is provided on the concrete peripheral wall B after the concrete peripheral wall B is constructed.

Next, a method of constructing the concrete tank T will be described. First, a construction hole D is excavated at the planned site. At this time, the corrugated plates 2a are joined to each other with the bolts 8 and the nuts 9 inside and / or outside of the construction hole D in accordance with the progress of the excavation of the construction hole D by the reverse winding method, and the outer form 2 is inserted into the construction hole D. Incorporate

After the completion of excavation of the construction hole D, a bobble stone 6 is spread on the bottom thereof, the bottom form 1 is laid thereon, and the inner form 3 is provided inside the bottom form 1 and the outer form 2. An injection pipe 11 and an air release pipe 12 are erected on the bottom surface of the lever.

Next, the inner mold 3, the bottom mold 1 and the outer mold 2
During this time, high-fluid concrete is injected from the injection pipe 11 and solidified, and the concrete bottom slab A and the concrete peripheral wall B
And build together.

Concrete bottom slab A and concrete peripheral wall B
After solidification, the inner mold 3, the injection pipe 11 and the air release pipe 12 are removed, and the lid mold 4 is placed on the concrete peripheral wall B.
Is provided, and ordinary ready-mixed concrete is poured thereon and solidified to complete the construction of the water tank T. The bottom mold 1 and the outer mold 2 are left as they are in the soil as discarded molds.

As described above, the outer mold frame 2 having a large shape has a structure in which a large number of corrugated plates 2a are joined and assembled.
Moreover, since each corrugated plate 2a can be carried by human power, the concrete water tank T can be constructed without trouble even in a narrow area where vehicles and heavy construction equipment cannot be used. Further, since the corrugated plate 2a has high strength and is hardly deformed due to collapse of the excavated soil, the quality of the concrete water tank T is improved in combination with the use of high fluidity concrete that solidifies without gaps. In addition, the process is 7
An effect of about 5% was obtained.

Concrete bottom slab A and concrete peripheral wall B
Can be constructed of ordinary concrete. In this case, the bottom form 1 may be omitted. Also, in some cases,
The concrete cover plate C may not be provided. When the bottom form 1 is formed into an inverted shape, the concrete volume decreases,
Although the cost can be reduced, the shape may not be inverted.

The number and shape of the corrugated plates 2a and the shape and volume of the outer mold frame 2 are not limited to those shown in the figures, but may be changed arbitrarily.

[0029]

As described above, according to the first aspect of the present invention, a high-quality concrete water tank which can be constructed at a relatively low cost in a narrow area by a reverse winding method by carrying a corrugated plate manually. Can be provided.

In the concrete tank according to the first aspect, when a bottom formwork is provided below the concrete bottom slab and the concrete bottom slab and the peripheral wall of the concrete are made of high-fluidity concrete, a concrete water tank of better quality can be obtained.

According to the third aspect of the present invention, a high-quality concrete water tank can be constructed in a narrow area where a transporting vehicle or construction heavy equipment cannot be used in a relatively short construction period and at low cost.

The method for constructing a concrete water tank according to claim 3, further comprising the step of laying a bottom formwork at the bottom of the construction hole, wherein the raw concrete is a high-fluid concrete.
A better quality concrete tank. Further, in the method for constructing a concrete water tank according to claim 4, when the bottom form is inverted, the concrete volume is reduced and the cost is reduced.

In the method for constructing a concrete water tank according to any one of claims 3 to 5, when the veneer of the outer formwork is a corrugated plate, the excavated soil in the construction hole may collapse. However, a concrete tank having a predetermined shape can be constructed without any trouble.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a plan view showing an example of an outer mold frame.

FIG. 3 is a view showing a joined state of a corrugated plate.

FIG. 4 is also a sectional view.

[Explanation of symbols]

 T Concrete water tank A Concrete bottom slab B Concrete peripheral wall C Concrete lid slab D Construction hole 1 Bottom form 2 Outer form 2a Corrugated plate 2b Flange 2c Through hole 3 Inner form 4 Cover form 6 Cutting stone 8 Bolt 9 Nut 11 Injection pipe 12 Air release pipe

Claims (6)

[Claims] 1. A concrete water tank in which a concrete peripheral wall is integrally connected to a concrete bottom slab, wherein an outer formwork to which a number of corrugated plates are joined is provided outside the concrete peripheral wall. 2. The concrete tank according to claim 1, wherein a bottom formwork is provided below the concrete bottom slab, and the concrete bottom slab and the concrete peripheral wall are made of high-fluidity concrete. 3. A step of joining a large number of veneers and incorporating an outer formwork into the construction hole while excavating a construction hole at a site where the concrete tank is to be constructed; and a bottom of the construction hole and the inside of the outer formwork. A step of assembling an inner formwork into the mold, and a step of casting and solidifying fresh concrete between the inner formwork and the bottom and outer formworks. 4. The method for constructing a concrete water tank according to claim 3, further comprising a step of laying a bottom formwork at a bottom of the construction hole, wherein the ready-mixed concrete is made of high-fluidity concrete. Method. 5. The method for constructing a concrete water tank according to claim 4, wherein the bottom mold has an inverted shape. 6. The method for constructing a concrete water tank according to claim 3, wherein a single plate of the outer formwork is a corrugated plate.