JPH07139051A - Centrifugal force steel pipe concrete column and manufacture thereof - Google Patents

Abstract

PURPOSE:To obtain a centrifugal force steel pipe excellent in fireproof performance regardless of small sectional area at a low cost by constructing a concrete molded body in a centrifugal force steel pipe by plural layers (a layer where a reinforcing material is mixed and a layer without a reinforcing material). CONSTITUTION:A steel pipe 1 having a designated length is rotated on the shaft center X. Concrete where a reinforcing material is mixed is supplied into the steel pipe 1. By the centrifugal force with the rotation, the concrete is compacted to form a reinforced concrete layer 2A. Subsequently, concrete to which a reinforcing material is not mixed is supplied into the steel pipe 1, and similarly the concrete is compacted by the centrifugal force to form a non-reinforced concrete layer 2B. Mortar M is filled in the cylindrical concrete. Thus, even if it has a sectional area smaller than that of the steel pipe concrete column formed by simply pouring concrete in the steel pipe, it is possible to obtain more excellent fire-proof performance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a centrifugal force steel pipe concrete column in which a concrete compact compacted by centrifugal force is loaded in a steel pipe, and a method for producing the same.

[0002]

2. Description of the Related Art Conventional centrifugal steel tube concrete columns have been constructed by loading concrete compacts compacted by centrifugal force into steel tubes. Also, although it is not a centrifugal steel tube concrete column with a structure in which a concrete compact compacted by centrifugal force is loaded into a steel pipe, it is a normal steel pipe with a structure in which concrete is simply poured into the steel pipe without being compacted by centrifugal force. As a concrete column, a concrete column in which steel fibers are mixed is also known.

[0003]

However, the conventional centrifugal steel tube concrete column described above has a shaft that is more compact than an ordinary steel tube concrete column constructed by simply loading concrete into a steel pipe without compacting the concrete by centrifugal force. It has excellent compressive strength and bending strength, that is, structural strength, and excellent fire resistance, but the drawback is that the cross-sectional area becomes extremely large in order to further improve its fire resistance. there were. That is, when performing fireproofing with a non-fireproof coating, the compressive strength of the loaded concrete compact is 1000 kg / c.
When that m ^2, and according to the centrifugal force steel concrete pole of current, in the range of 2 hours fire, the concrete cross-section needed to meet the structural strength usually required to satisfy the refractory time Since it is more than the concrete cross section, it is almost possible to achieve fire resistance for 2 hours with the non-fireproof coating, even though the cross section of the concrete compact to be loaded is determined by the concrete cross section required in terms of structural strength. Due to the fire resistance of the refractory coating, the cross section of the column does not need to be extra large. However, if it is attempted to achieve fire resistance by a non-fire resistant coating within the range of fire resistance for 3 hours with the structure satisfying the fire resistance for 2 hours, the concrete cross section required for the fire resistant surface is larger than the concrete cross section required for the structural bearing capacity. As a result, the cross section of the concrete compact to be loaded must be determined not by the concrete cross section required for the structural bearing surface but by the concrete cross section required for the fire resistant surface, and the improvement of the fire resistant performance by the non-fire resistant coating is achieved. Inevitably, the pillars had to be large in cross section.

On the other hand, according to the steel pipe concrete pillar in which the steel fiber is mixed in the concrete compact to be loaded, since the steel fiber is a heat-resistant reinforcing material, such a non-reinforced steel fiber is not mixed. Compared to ordinary steel pipe concrete loaded with concrete compacts, the concrete cross-section required for fireproofing is small and the cross-section of the concrete compacts to be loaded can be made small, but the expensive steel is used throughout the concrete compacts to be loaded. Since it was necessary to mix a sufficient amount of fibers, it was very expensive.

An object of the present invention is to improve the fire resistance performance while suppressing the increase in cost and the increase in cross section, paying attention to the peculiarity in manufacturing the centrifugal steel tube concrete column.

[0006]

A first feature of a centrifugal steel tube concrete column according to the present invention is that the concrete compact is composed of a reinforced concrete layer containing a heat-resistant reinforcing material and a non-reinforced concrete layer containing no heat-resistant reinforcing material. The point is that it has a multi-layer structure inside and outside.

A second feature of the centrifugal steel tube concrete column according to the present invention resides in that, in the first feature, the reinforced concrete layer is arranged on the outermost side.

A third characteristic of the centrifugal steel tube concrete column according to the present invention resides in that the reinforced concrete layer is arranged on the innermost side in the first characteristic.

The first feature of the method for producing a centrifugal steel pipe concrete column of the present invention is to rotate the steel pipe around its axis and to supply the concrete in a fluidized state into the steel pipe by centrifugal force. The concrete pouring process is carried out multiple times by compacting into a tubular shape with a concrete casting process to form a tubular concrete of a set wall thickness that integrates each tubular feeding concrete, and the concrete pouring process A method for creating a centrifugal force steel pipe concrete column in which a concrete compact compacted by centrifugal force is loaded into a steel pipe by performing a curing and curing step of curing and curing the cast concrete, the concrete placing step The first concrete supply in the process of forming the tubular supply concrete into the concrete mixed with heat resistant reinforcement Used performed, the molding of the cylindrical supply concrete by the concrete supply after reinforcements lies in performed using a concrete which has not been mixed.

The second feature of the method for producing a centrifugal steel pipe concrete column of the present invention is to rotate the steel pipe around its axis and to supply the concrete in a fluid state into the steel pipe by centrifugal force. The concrete pouring process is carried out multiple times by compacting into a tubular shape with a concrete casting process to form a tubular concrete of a set wall thickness that integrates each tubular feeding concrete, and the concrete pouring process A method for creating a centrifugal force steel pipe concrete column in which a concrete compact compacted by centrifugal force is loaded into a steel pipe by performing a curing and curing step of curing and curing the cast concrete, the concrete placing step The final concrete supply in the process of forming the cylindrically-supplied concrete. Done by feeding, the molding of the cylindrical supply concrete by previous concrete supply reinforcement lies in carried out by feeding the concrete not mixed.

[0011]

[Operation] Centrifugal force The concrete formed body of the steel pipe concrete column is made by centrifuging the supplied concrete by supplying the concrete in a fluid state into the form while rotating the cylindrical form around its axis. It is created by compacting into a cylindrical shape with force, and curing and hardening the cylindrical concrete.As a form of supplying concrete in a fluidized state into the formwork, the entire amount of concrete is Not only the batch supply form of supply, but also the distributed supply form of supplying in several times can be adopted. Further, generally, in order to uniformly disperse the fluidized concrete in the mold with good workability, the latter distributed supply mode tends to be adopted in many cases.

Further, when considering the usage conditions of centrifugal steel tube concrete columns, in some cases, a column having the highest axial compression strength and bending strength is required, and in some cases, bending strength is more important than axial compression strength. There are also cases where a column with a special structure is required, and conversely, a column with a structure that emphasizes axial compression strength rather than bending strength is required.

The first of the centrifugal steel tube concrete columns of the present invention
According to the features of the above, paying attention to the above points, the concrete molded body in the steel pipe is configured into an inner and outer multi-layer structure consisting of a reinforced concrete layer mixed with a heat-resistant reinforcing material and a non-reinforced concrete layer not mixed. Because of the existence of the reinforced concrete layer, it is possible to improve the fire resistance and the structural proof strength as compared with the conventional centrifugal steel tube concrete column which is composed of the whole concrete molded body without the reinforcing material. Moreover, the amount of expensive reinforcing material used can be reduced. And, it is not possible to improve both bending strength and axial compression strength equally, but by arranging the reinforced concrete layer outside,
Bending strength can be improved preferentially, and conversely, by arranging it inside, axial compression strength can be improved preferentially. Alternatively, or by selecting the thickness of the reinforced concrete, it is possible to obtain a product having specifications that meet the usage conditions.

Second Centrifugal Steel Tube Concrete Column of the Present Invention
According to the feature (1), since the reinforced concrete layer is arranged on the outermost side, the bending proof stress of the bending proof stress and the axial compression proof stress can be increased mainly.

Third Centrifugal Steel Tube Concrete Column of the Present Invention
According to the feature (1), since the reinforced concrete layer is arranged on the innermost side, the axial compressive strength among the bending strength and the axial compressive strength can be increased mainly.

According to the first feature of the method of the present invention, the tubular supply formed by the first supply of the concrete mixed with the reinforcing material among the concrete supplied separately into the steel pipe by the curing and hardening after the casting. The concrete becomes the reinforced concrete layer, while the tubular feed concrete formed by the supply of the concrete not mixed with the reinforcing material later becomes the non-reinforced concrete layer, so the outermost side is the reinforced concrete layer and the inner side is the non-reinforced concrete layer. It is possible to prepare a concrete molded body having an inner and outer two-layer structure and having increased fire resistance and bending strength, that is, a concrete molded body of a centrifugal force steel tube concrete column according to claim 2. Moreover,
Since the steel pipe itself is used as a form for placing and forming the concrete compact to be loaded into the steel pipe, no special form is required, and moreover, the concrete is placed and poured (filled) into the steel pipe. It becomes the work of loading the concrete formed body into the work, and the work can be shared.

According to the first feature of the method of the present invention, among the concretes supplied separately in the steel pipe by curing and hardening after casting, the tubular shape formed by the supply of the concrete without the reinforcing material in the front. The supplied concrete becomes the non-reinforced concrete layer, while the tubular supplied concrete molded by the last supply of the concrete mixed with the reinforcing material becomes the reinforced concrete layer, so the outer side is the non-reinforced concrete layer and the innermost side is the reinforced concrete layer. It is possible to prepare a concrete molded body having an inner and outer two-layer structure and having increased fire resistance and bending resistance, that is, a concrete molded body of a centrifugal steel tube concrete column according to claim 3. Moreover, since the steel pipe itself is used as a formwork for placing and forming the concrete formed body to be loaded into the steel pipe, no special formwork is required, and the concrete placing work can be performed by using the concrete formed body into the steel pipe. It becomes a loading work, and the work can be combined.

[0018]

Therefore, according to the present invention, the amount of expensive reinforcing material such as steel fiber used is reduced to economically improve the fire resistance performance of a centrifugal steel tube concrete column and at the same time increase the structural strength. I was able to do it.

According to the second aspect of the present invention, it is possible to provide a centrifugal steel pipe concrete column which is increased in bending strength in a focused manner and adapted to a use condition requiring a large bending strength.

According to the third aspect of the present invention, it is possible to provide a centrifugal steel tube concrete column which is adapted to a use condition that requires a large axial compression strength by intensively increasing the axial compression strength.

According to the fourth aspect of the present invention, the centrifugal force can achieve excellent performance especially in bending strength while reducing the cost of manufacturing equipment by eliminating the need for a formwork and improving the workability of manufacturing by sharing work. It is possible to create steel pipe concrete columns.

According to the fifth aspect of the present invention, it is possible to reduce the production equipment cost by eliminating the need for a formwork and improve the production workability by sharing the work, and at the same time, it is possible to exhibit excellent performance in terms of axial compression strength. Centrifugal steel tube concrete columns can be created.

[0023]

EXAMPLES Example 1 Centrifugal steel pipe concrete columns are, as shown in FIGS. 1 and 2, in a steel pipe 1 having a predetermined column length.
A tubular concrete compact 2 compacted by centrifugal force is loaded into the steel pipe 1 over the entire length thereof, and a mortar compact 3 is loaded into the concrete compact 2.

The concrete molded body 2 has an inner and outer two-layer structure, the outer layer is constituted by a reinforced concrete layer 2A containing a heat-resistant reinforcing material, and the inner layer is formed by mixing the reinforcing material. Not configured in unreinforced concrete layer 2B. The reinforcing material is a short fiber (steel fiber) having a length of about 20 to 30 mm and a diameter of 0.
However, other examples include aramid fiber and short fiber such as carbon fiber. That is, the type of fiber as the reinforcement is appropriately determined according to the required performance, and the diameter and length of the reinforcing material are also appropriately determined according to the type of fiber used and the required performance. It is decided. The mixing amount of the reinforcing material in the reinforced concrete layer 2A is about 5% of the weight of the concrete, but it may not be so. In other words, the amount of reinforcing material mixed in is
It can be appropriately adjusted (determined) according to the required performance.

Next, a method of making the centrifugal steel tube concrete column will be described. The production method is such that the steel pipe 1 held in a posture in which the shaft core X is horizontally positioned is used as a concrete formwork, and the steel pipe 1 is rotated around the shaft core X, while concrete in a fluid state is supplied into the steel pipe 1. By doing so, the concrete is compacted into a tubular shape by centrifugal force and the concrete is supplied twice to form each tubular concrete c.
Concrete pouring process to form tubular concrete C with a set wall thickness, which is integrated <see <(a) and (b) in FIG. 3>
And a mortar filling step of filling the mortar M in a fluid state into the tubular concrete C (see (c) of FIG. 3), and a tubular placing concrete C by the concrete placing step and a mortar filling step It is carried out by performing a curing and curing step of curing and curing the mortar M. In the concrete placing step, forming of the tubular supply concrete c by the first concrete supply is performed by using the concrete in which the reinforcing material is mixed, and the forming of the tubular supply concrete c by the subsequent concrete supply is reinforced. Use concrete that does not contain wood.

According to this production method, the reinforcing concrete layer 2A is formed by hardening the cylindrically supplied concrete c mixed with the reinforcing material which is firstly supplied and poured out of the cylindrically cast concrete C. The non-reinforced concrete layer 2 that is integrated with the reinforced concrete layer 2A by hardening the tubular supply concrete c that does not contain the reinforcement material
B is formed, and the mortar compact 3 is formed from the cured mortar M.

[Second Embodiment] The difference from the first embodiment is that
As shown in FIG. 4, the inner layer constituting the concrete molded body 2 having the inner-outer two-layer structure is composed of a reinforced concrete layer 2A in which a heat-resistant reinforcing material is mixed, and the outer layer is constituted by the reinforcing material. It is composed of the non-reinforced concrete layer 2B which is not mixed, and the other structure is the same as that of the first embodiment, and therefore the description thereof is omitted.

A method for producing the centrifugal force steel tube concrete column will be described. The difference between the method of making and the method of making shown in Example 1 is that in the concrete supplying step, forming of the tubular supply concrete c by the first concrete supply is performed.
It is the same as in Example 1 except that the concrete containing no reinforcing material is used, and the cylindrical concrete c to be supplied by the subsequent concrete supply is formed using concrete containing the reinforcing material.

According to this producing method, the non-reinforced concrete layer 2B is formed by hardening the tubular supply concrete c which does not contain the reinforcing material and which is first supplied and cast out of the cylindrical cast concrete C. The tubular supply concrete c mixed with the reinforcing material, which has been supplied and cast later, is hardened so that the reinforced concrete layer 2 integrated with the non-reinforced concrete layer 2B.
A is formed.

[Other Embodiment] In the above embodiment, one reinforced concrete layer 2A and one non-reinforced concrete layer 2B are used.
The concrete molded body 2 was constructed from the above, but as shown in (a) and (b) of FIG. 5 and (a) and (b) of FIG. 6, a plurality of non-reinforced concrete layers were formed in the same manner as the plurality of reinforced concrete layers 2A. The concrete molded body 2 may be configured from 2B. FIG. 5 shows the same number of reinforced concrete layers 2A and non-reinforced concrete layers 2B, and FIG. 6 shows different numbers.

In the above-mentioned embodiment and another embodiment, one tubular supply concrete c to one reinforced concrete layer 2A is used.
Was formed and one non-reinforced concrete layer 2B was formed from one cylindrical supplied concrete c, but when the wall thickness of the reinforced concrete layer 2A or the non-reinforced concrete layer 2B is large, As shown in (b), they are composed of a plurality of tubular supply concretes c.

In the above-mentioned embodiment, the steel pipe 1 was used as a mold for producing the concrete molded body 2. However, a concrete frame was separately provided to prepare the concrete molded body 2, and the concrete molded body 2 was attached to the steel pipe 1. It may be loaded to form a centrifugal steel tube concrete column.

In the above embodiments, the reinforcing material is a fiber, that is, a fibrous material. However, the reinforcing material is well mixed with concrete and is made of concrete at the time of pouring and pouring into the formwork. The shape and the size are not limited as long as the fluidity is not extremely lowered.

Although the centrifugal force steel pipe concrete column having the structure in which the mortar molded body 3 is loaded is shown in the above-mentioned embodiment and the other examples, the centrifugal force steel pipe concrete column of the present invention is as shown in FIG. 8 has a structure in which a mortar molded body 3R containing a reinforcing material is loaded instead of the mortar molded body 3 or a cavity H is formed without loading the mortar molded body 3 as shown in FIG. 8 has a structure in which a concrete molding CR containing a reinforcing material is loaded in place of the mortar molding 3 as shown in FIG. 8C. As shown in FIG. 8D, the mortar molding Instead of 3, the structure may be one in which a concrete molded product CAR containing no reinforcing material is loaded. It should be noted that although the drawing shows the one based on the centrifugal force steel pipe concrete column having the structure described in Example 1,
Of course, this another embodiment may be based on the centrifugal force steel pipe concrete column having the structure shown in the second embodiment or the other embodiment described above.

In the figure, the steel pipe 1 is shown as a quadrangular cylinder, but the steel pipe 1 is a round cylinder, a pentagon, or the like.
It may be a polygonal tube such as a hexagon. That is, the shape of the steel pipe 1 can be appropriately changed.

It should be noted that reference numerals are given in the claims for convenience of comparison with the drawings, but the present invention is not limited to the structures of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a main part of a centrifugal steel tube concrete column showing Example 1.

FIG. 2 is a transverse cross-sectional view of a centrifugal steel tube concrete column showing Example 1.

FIG. 3 is a cross-sectional view in each step of producing a centrifugal steel tube concrete column showing Example 1.

FIG. 4 is a transverse sectional view of a centrifugal steel tube concrete column showing Example 2.

FIG. 5 is a transverse cross-sectional view of each centrifugal steel tube concrete column showing another embodiment.

FIG. 6 is a transverse sectional view of each centrifugal steel tube concrete column showing another embodiment.

FIG. 7 is a cross-sectional view of each centrifugal steel tube concrete column showing another embodiment.

FIG. 8 is a cross-sectional view of each centrifugal steel tube concrete column showing another embodiment.

[Explanation of symbols]

 2 Concrete molded body 1 Steel pipe 2A Reinforced concrete layer 2B Non-reinforced concrete layer c Cylindrical supply concrete C Concrete

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akio Kodaira 1-5 Otsuka, Inzai-cho, Inba-gun, Chiba Incorporated Takenaka Corporation Technical Research Institute (72) Kenji Handa 3-4 Honmachi, Chuo-ku, Osaka-shi, Osaka No. 10 within Nippon Concrete Industry Co., Ltd.

Claims (5)

[Claims] 1. A centrifugal force steel tube concrete column in which a concrete compact (2) compacted by centrifugal force is loaded in a steel pipe (1), said concrete compact (2).
The reinforced concrete layer (2
Centrifugal steel tubular concrete columns having an inner and outer multi-layer structure consisting of A) and a non-reinforced concrete layer (2B) that does not mix. 2. The centrifugal steel tube concrete column according to claim 1, wherein the reinforced concrete layer (2A) is arranged on the outermost side. 3. A centrifugal steel tube concrete column according to claim 2, wherein the reinforced concrete layer (2A) is arranged on the innermost side. 4. Concrete for compacting the supplied concrete into a tubular shape by centrifugal force by supplying concrete in a fluid state into the steel tube (1) while rotating the steel tube (1) around its axis. Concrete pouring process of forming a concrete wall (C) having a set wall thickness in which each of the cylindrical concrete feeds (c) is integrated by performing plural times of feeding, and a tubular pouring concrete by the concrete pouring process A method of producing a centrifugal force steel pipe concrete column in which a concrete compact (2) compacted by centrifugal force is loaded into a steel pipe (1) by performing a curing and curing step of curing (C). The first concrete feed in the concrete placing step is used to form the tubular feed concrete (c) by using concrete mixed with a heat resistant reinforcing material. A method for producing a centrifugal force steel pipe concrete column, which is performed by forming the tubular supply concrete (c) by the subsequent concrete supply using the concrete in which the reinforcing material is not mixed. 5. Concrete for compacting the supplied concrete into a tubular shape by centrifugal force by supplying concrete in a fluid state into the steel tube (1) while rotating the steel tube (1) around its axis. Concrete pouring process of forming a concrete wall (C) having a set wall thickness in which each of the cylindrical concrete feeds (c) is integrated by performing plural times of feeding, and a tubular pouring concrete by the concrete pouring process A method for producing a centrifugal force steel pipe concrete column in which a concrete compact (2) compacted by centrifugal force is loaded into a steel pipe (1) by performing a curing and curing step of curing (C). Forming the tubular supply concrete (c) by the last concrete supply in the concrete placing step, supplying concrete containing heat-resistant reinforcement material A method for producing a centrifugal steel tube concrete column, wherein the tubular supply concrete (c) by the previous concrete supply is formed by supplying concrete containing no reinforcing material.