JPH0679708A - Formation of composite concrete structural material - Google Patents

Abstract

PURPOSE:To form surface irregularities readily and safely by using a roller having protruding parts or light aggregate or ice in small lumps before hardening when the irregularities are formed on the surface of concrete, which has been injected at the previous stage when the concrete is injected in many stages and the composite concrete structural material is formed. CONSTITUTION:A rotary table 12 is turned, and concrete is injected into a framework 1. Before the complete hardening, the table 12 is rotated, and an inner wall 3 of a hollow part 2 is pressed with a free roller 4 having protruding parts 5. When the concrete contains light aggregate, the parts of the aggregate are exposed, and the irregularities are formed. When the aggregate is not contained, the light aggregate in small lumps is dispersed and pushed before the complete hardening. Or ice in small lumps is dispersed and pushed, or the lumps of ice are mixed at the final stage of the concrete injection. The concrete is injected and hardened in the hollow part 2 of the obtained hollow, thin precast concrete, and the composite concrete pole is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a composite concrete structural material such as a concrete column using hollow thin precast concrete.

[0002]

2. Description of the Related Art Conventionally, for example, as a method of forming a concrete column, a precast method, that is, a method of manufacturing a concrete column in advance and transporting the concrete column to a construction site to assemble it, has been used recently. As the number of specialists is reduced, and because it is lighter than all-precast materials and does not require a large crane, as an improved method of this method, so-called hollow thin precast concrete is used, A method of placing concrete at the construction site to form a composite concrete column in the hollow part has been widely adopted.

This hollow thin-wall precast concrete is usually manufactured by a centrifugal molding method, so that the contact area with the concrete cast at the construction site is increased to achieve structural integration and to provide a strong concrete column. In addition, a desired uneven portion is provided on the inner wall surface of the hollow portion.

For this purpose, conventionally, as shown in FIG.
The cotter part 9 is placed in the mold 1 placed on the turntable 12.
The method of arranging the inner formwork 10 having the above, as shown in FIG. 5, the method of roughening the inner wall surface 3 of the hollow portion with the wire brush 11 at the final stage of centrifugal molding and before the complete hardening of concrete is adopted. However, in the former case, the inner mold that can withstand the centrifugal force of nearly 30 G at the time of molding becomes large in scale, and the equipment and work will inevitably become large-scale, and a special machine will be used to remove the inner mold. However, in the latter case, the structural joint strength between the hollow thin precast concrete and the subsequent concrete is not sufficient at the uneven portion formed by the wire brush 11, and the wire brush is normally used. Since it is carried by the worker, the danger associated with the high speed rotation of the rotary table 12 is unavoidable, and the force exerted by the wire brush is sufficiently controlled. It is impossible to shape change of the uneven portion increases, even has been difficult process control.

[0005]

Therefore, the object of the present invention is to include an improved method for forming the required unevenness on the surface of the concrete preform formed in the preceding step,
It is to provide a new method for forming a composite concrete structural material using hollow thin precast concrete or the like.

[0006]

That is, the present invention is
(1) When concrete is cast or poured in multiple stages to form a composite concrete structural material, the surface of the concrete cast or poured in the previous stage before hardening is pressed by a free-rotating roller having a protrusion. After that, let it cure,
Form a concrete preform with surface irregularities,
Next, a method for forming a composite concrete structural material, which comprises pouring or pouring subsequent concrete so as to be bonded to the surface of the concrete preform having the uneven portion, and (2) multi-stage concrete In forming a composite concrete structural material by pouring or pouring into, concrete containing or not containing small aggregated lightweight aggregate is used as concrete to be poured or injected in the previous step, and at least the concrete is When the lightweight aggregate is not contained, small aggregated lightweight aggregate is sprayed and pressed onto the concrete surface before hardening, followed by hardening to form a concrete preform having surface irregularities, and then the concrete preform. The subsequent concrete is poured or poured and hardened so as to bond with the surface having the uneven part of the object. The method of forming a composite concrete structure material, or (3) the final step of placing or injecting concrete used in the previous step in forming or injecting concrete in multiple stages to form a composite concrete structure material Use concrete mixed with small lumps of ice in the stage, or sprinkle small lumps of ice on the surface before hardening of the concrete that was placed or poured in the previous stage, and then harden it to have surface irregularities A method for forming a composite concrete structural material, which comprises forming a concrete preform and then pouring or pouring the subsequent concrete so that the concrete preform is joined to the surface of the concrete preform having the uneven portions. Consists of.

In these methods, pouring or pouring concrete in multiple stages means an operation of pouring or pouring concrete in at least two stages, and in each stage, it is continuously or discontinuously poured. It includes an operation of setting or injecting.

The present invention will be described in detail below with reference to the drawings.

First, FIG. 1 shows a typical example of forming hollow thin precast concrete by centrifugal molding according to the invention of claim 1. In the figure, 1 is a form, 2 is a hollow part, 3 is an inner wall of the hollow part, 4 is a free rotating roller having a protruding part 5, and 12 is a rotary table. In this method, concrete is poured into the mold 1 while rotating the turntable 12. When a predetermined amount of concrete has been poured, the rotation of the rotary table 12 is stopped, and the poured concrete is cured and cured while being placed on the rotary table 12 or at another place, and then deframed to remove the hollow thin-walled precast concrete. Take it out. At this time, the inner wall surface 3 of the hollow portion 2 of the concrete is rotated while rotating the turntable 12 at an appropriate time before the concrete is completely hardened.
Is pressed by the free-rotating roller 4 having the protrusions 5, to form hollow thin precast concrete having surface irregularities. At the time of pressing with the free rotating roller 4, the hardening of the concrete has progressed to some extent,
It can be appropriately selected as long as the required shape of the formed concavo-convex portion is maintained, but it is usually the final stage of curing. The number of the protruding portions 5 of the free-rotating roller 4 is appropriately selected according to the thickness and length of the final concrete column or the like, the material of the concrete, etc., but it is usually 2 or more, preferably 4 or more. More than one place will be targeted. Further, the shape of the protruding portion 5 is preferably such that the structural joint strength with the subsequent concrete becomes large, and examples thereof include a pin and a cotter. Although the operating mechanism of the free rotating roller 4 can be manually operated, it is preferably automatic from the viewpoint of safety, quality control of the uneven shape formed on concrete, and the like. In the case of this automatic operation, it is preferable to add a mechanism for automatically lowering and moving the free-rolling roller 4 to a pressed state at an appropriate hardening time of concrete.

By forming or injecting subsequent concrete into the hollow portion 2 of the hollow thin wall precast concrete having the required surface irregularities on the inner wall 3 of the hollow portion thus formed and hardening it, the required composite concrete columns are formed. . In this case, it is possible to form a hollow composite concrete material by using the rotary table 12 as it is, for example.

FIG. 1 shows a case where the concrete preform is hollow thin precast concrete, but this method can be applied to the formation of, for example, a composite concrete plate or a composite concrete block. In this case, the joint surface with the subsequent concrete may be pressed by the free rotating roller 4 at an appropriate time before the complete hardening of the concrete preform having a plate shape or the like, and the rotary table 12 is not always necessary. I don't.

According to the first aspect of the present invention, a concrete preform such as hollow thin precast concrete is usually formed in a factory, and subsequent concrete is cast or poured at a construction site, but all steps are performed in the factory. It can be carried out, or if the required equipment is installed, the whole process can be carried out at the construction site.

Next, FIG. 2 shows a typical example of forming hollow thin precast concrete by centrifugal molding according to the invention of claim 2. In the figure, 1 is a formwork, 2 is a hollow part, 3 is an inner wall of the hollow part, 6 is a small aggregate lightweight aggregate, 12
Is a turntable. In this method, the lightweight aggregate 6
Means an aggregate lighter in specific gravity than concrete, and the difference in specific gravity between the two is appropriate in consideration of the magnitude of centrifugal force generated by the rotation of the rotary table 12 and the joint strength between the hollow thin precast concrete and the subsequent concrete. Select.
In this case, the small lump-shaped lightweight aggregate 6 may or may not be premixed with concrete. When the concrete contains the lightweight aggregate 6, a part of the lightweight aggregate 6 is exposed on the surface of the inner wall of the hollow portion of the precast concrete to form a desired uneven portion, and the centrifugal force generated by the rotation of the rotary table 12 acts. As a result, the lightweight aggregate 6 having a low specific gravity is transferred to the inner wall 3 of the hollow portion 2.
It will be exposed a lot on the surface. In addition, lightweight aggregate 6
Can be mixed only in the concrete used in the final stage of pouring, and in that case, the required unevenness can be formed with a small amount of the lightweight aggregate 6. On the other hand, if at least the concrete does not contain the lightweight aggregate 6, the small aggregated lightweight aggregate 6 should be scattered and pressed onto the surface of the inner wall 3 of the hollow portion 2 at an appropriate time before the injected concrete is completely hardened. By doing so, the lightweight aggregate 6 is immersed in the hollow inner wall 3 side to some extent. In this case, it is necessary that the lightweight aggregate 6 can be held in a protruding state from the surface of the inner wall 3 of the hollow portion. The degree to which the scattered lightweight aggregates 6 are pressed is appropriately selected according to the size of the lightweight aggregates 6 and the required size of the convex portions. Although it is possible to manually spray and press the lightweight aggregate 6, it is preferable to add a mechanism for automatically spraying and pressing from the viewpoint of safety and quality control. Further, when the concrete contains the lightweight aggregate 6, the lightweight aggregate 6 can be further sprayed.

A desired composite concrete column is formed by injecting the subsequent concrete into the hollow portion 2 of the hollow thin precast concrete having the required surface irregularities on the inner wall 3 of the hollow portion thus formed and hardening it. In this case, it is possible to form a hollow composite concrete material by using the rotary table 12 as it is, for example.

FIG. 2 shows a case where the concrete preform is hollow thin precast concrete, but this method can be applied to the formation of, for example, a composite concrete plate or a composite concrete block. In this case, at least in the final stage of the casting in the previous stage, concrete containing a small aggregate of lightweight aggregate 6 is used, or in the case where the concrete does not contain the lightweight aggregate 6, it was placed in the previous stage. It is sufficient to sprinkle and press small aggregated lightweight aggregates 6 on the joint surface with the subsequent concrete at an appropriate hardening time of the concrete.
2 is not always necessary.

Also in the second aspect of the present invention, the concrete preform such as hollow thin precast concrete is usually formed in the factory, and the subsequent concrete is cast or poured at the construction site, but all the steps are performed in the factory. It can be carried out, or if the required equipment is installed, the whole process can be carried out at the construction site.

Next, FIG. 3A and FIG.
1 illustrates a typical example of forming hollow thin precast concrete by centrifugal molding according to the described invention. In the figure, 1 is a mold, 2 is a hollow portion, 3 is an inner wall of the hollow portion, 7 is a small piece of ice, 8 is a concave portion left after the ice 7 is melted, and 12 is a rotary table. In this method, in the final stage of pouring or pouring the concrete used in the previous stage, small ice cubes 7 are mixed in the concrete, or
Alternatively, before the concrete poured or poured in the previous stage is completely hardened, small lumps of ice 7 are scattered and pressed on the surface of the inner wall 3 of the hollow portion. In the case of the former, since the mixed ice 7 has a low specific gravity, it is floated on the surface side of the hollow inner wall 3 by the rotation of the rotary table 12 and melted during the hardening of the concrete to form the concave portion 8 in the inner wall 3. become. In the latter case, the sprayed and pressed ice 7 immerses in the concrete,
It melts during the hardening of the concrete to form a required recess in the hollow inner wall 3. The extent to which the sprayed ice 7 is pressed is appropriately selected according to the size of the ice 7 and the size of the required recesses, and it is possible to immerse the ice 7 almost completely. Care must be taken to ensure that the required openings remain after melting. Also in this method, it is possible to pour concrete containing ice 7 at the final stage and further spray the ice 7. The ice 7 may be sprayed and pressed manually, but it is preferable to add a mechanism for automatically spraying and pressing the ice 7 from the viewpoint of safety and quality control.

A desired composite concrete column is formed by injecting the subsequent concrete into the hollow portion 2 of the hollow thin precast concrete having the required surface irregularities on the inner wall 3 of the hollow portion thus formed and hardening it. In this case, it is possible to form a hollow composite concrete material by using the rotary table 12 as it is, for example.

FIG. 3 shows the case where the concrete preform is hollow thin precast concrete, but this method can be applied regardless of the shape of the final concrete formation.
For example, it can be applied to the formation of a composite concrete plate, a composite concrete block, etc. In these cases, concrete containing small lumps of ice 7 is used in the final stage of casting, or If the ice does not contain ice 7, it is sufficient to sprinkle and press small lumps of ice 7 on the joint surface with the subsequent concrete at an appropriate hardening time of the concrete placed in the previous stage, and the rotary table 12 Not necessarily required.

Also in the third aspect of the invention, usually, a concrete preform such as hollow thin precast concrete is formed in a factory, and subsequent concrete pouring or pouring is carried out at the construction site, but all steps are performed in the factory. It can be carried out, or if the required equipment is installed, the whole process can be carried out at the construction site.

[0021]

The present invention having the above construction has the following effects.

By using a free-rotating roller, small aggregate lightweight aggregate or small aggregate ice, surface irregularities of a concrete preform can be formed easily, safely and at low cost. The quality of the roughened surface is also excellent.

In any of the methods of the present invention, all the steps can be carried out at a factory or a construction site, or part of them can be carried out at a factory and the rest can also be carried out at a construction site. It has a high degree of freedom in work and can form a composite concrete structural material extremely rationally.

The degree of freedom in designing the shape and structure of the composite concrete structural material to be formed is great, and it is possible to meet various needs.

[Brief description of drawings]

FIG. 1 is a plan view illustrating the method of the present invention using a freely rotating roller.

FIG. 2 is a plan view illustrating the method of the present invention in which small aggregate lightweight aggregates are used.

FIG. 3 is a plan view illustrating the method of the present invention using small pieces of ice.

FIG. 4 is a plan view illustrating a conventional method using an inner mold with a cotter.

FIG. 5 is a plan view illustrating a conventional method using a wire brush.

[Explanation of symbols]

 1 Formwork 2 Hollow Part 3 Hollow Part Inner Wall 4 Free Rotating Roller 5 Free Rotating Roller Protrusion 6 Lightweight Aggregate 7 Ice 8 Recess 9 Cotter Part 10 Inner Form 11 Wire Brush 12 Rotating Table

Claims (3)

[Claims] 1. When the concrete is cast or poured in multiple stages to form a composite concrete structural material, the surface of the concrete cast or poured in the preceding stage before hardening is
After pressing with a free-rotating roller having a protrusion, it is cured to form a concrete preform having surface irregularities, and then the subsequent concrete is joined to the surface of the concrete preform having the irregularities. A method for forming a composite concrete structural material, which comprises pouring or pouring and curing. 2. When concrete is cast or poured in multiple stages to form a composite concrete structural material, the concrete to be cast or poured in the preceding stage contains or does not contain small aggregated lightweight aggregates. When concrete is used, and at least when the concrete does not contain a lightweight aggregate, a small preform of the aggregate is sprayed and pressed onto the concrete surface before hardening, followed by hardening, and a concrete preform having surface irregularities. A method for forming a composite concrete structural material, comprising the steps of: forming, and then hardening by pouring or injecting a subsequent concrete so as to join the surface of the concrete preform having the uneven portion. 3. When concrete is poured or poured in multiple stages to form a composite concrete structural material, concrete containing small lumps of ice is used in the final stage of casting or pouring in the previous stage, or Alternatively, small lumps of ice are sprayed and pressed onto the concrete surface before hardening of the concrete cast or poured in the previous step, and then it is hardened to form a concrete preform having surface irregularities, and then the concrete A method for forming a composite concrete structural material, which comprises pouring or pouring a subsequent concrete so as to be hardened so as to be bonded to the surface of the preform having the uneven portion.