JP2556952B2 - Manufacturing method for tubular concrete products - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe suitable for producing a tubular concrete product such as a box culvert for providing a sewer, a water conduit, a drainage canal, an underpass, a common ditch, or a water tank underground. The present invention relates to a method for manufacturing a concrete concrete product.

[0002]

2. Description of the Related Art It is widely practiced to join a plurality of tubular concrete blocks such as box culverts to construct the sewer system mentioned above. For straight lines,
That is, there are a standard type in which both joint end surfaces are parallel, and a curve type, that is, one in which one joint end surface is inclined with respect to the other joint end surface. To join such tubular concrete blocks, the tension members are inserted through the through holes provided in the four corners thereof in the direction of the central axis, and the ends of the respective tension members are connected to the nuts in the connection box communicating with the through holes. It is fixed at. This insertion hole is formed by penetrating the end plate of the formwork at the time of manufacturing and attaching the bar-shaped member to the formwork, and then pulling out the bar-shaped member when the concrete reaches a predetermined strength after the concrete is placed. ing.

By the way, the number of tubular concrete blocks for curves is smaller than that for straight ones, and it is required that the length and the angle of inclination between the joint end faces be varied depending on the degree of the curve. However, it is uneconomical to mold with a dedicated mold. Therefore, conventionally, a partition plate corresponding to the slanted joint end face is arranged in a mold for molding a standard type tubular concrete block, and the tubular concrete block for such a curve is molded. ing.

[0004]

In the above configuration,
Since a space equal to or longer than the length is required to pull out the rod-shaped member, the site area required for manufacturing becomes large, and on the other hand, since there is a lot of empty space, it was difficult to increase the manufacturing efficiency.

In addition, the above-mentioned curved tubular concrete block uses a partition plate at the time of its manufacture. Such a partition plate is a standard type tubular concrete block at various angles in the space inside the formwork. It must be arranged so that no gap is formed in a state inclined with respect to the end surface of the mold for molding. However, in the conventional construction method, the partition plate could not be supported from the concrete pouring space side, and thus there was a problem that the position was likely to be displaced during the work. That is, the partition plate is positioned and attached by disposing the projecting support bar between the partition plate and the end plate, and when a force is applied from the surface on the side without the projecting support bar,
It is easily misaligned. Regarding the installation of this partition plate,
Since the rod-shaped member has a length such that the end thereof projects from the mold for facilitating withdrawal, it is difficult to fix the partition plate only by penetrating the partition plate, and it is not useful for disposing the partition plate. Absent. Further, when the partition plate is twisted or misaligned, there is also a problem that the defective product rate is high due to that.

An object of the present invention is to solve such a problem.

[0007]

The present invention takes the following means in order to achieve such an object. That is, the method for manufacturing a tubular concrete product according to the present invention corresponds to the predetermined positions of the four corners through which the tension members are inserted in the form for molding the standard type tubular concrete product having both joint end surfaces parallel to each other. At the position, a pipe member having approximately the same size as the inner diameter of the form and having a connecting box for connecting the tension members at its middle portion is arranged with both ends fixed to the form. The concrete product is manufactured by placing concrete in the formwork and burying the connecting box and the pipe member in the concrete.

In particular, in the case of manufacturing a tubular concrete product for curves, the formwork is provided with an inclined partition plate for inclining at least one joint end surface, and one end of the pipe member is fixed to the inclined partition plate. You can do it.

[0009]

According to the present invention, the insertion hole for passing the tension member is formed by the pipe member integrally provided with the connecting box. That is, the insertion hole is not formed of cast concrete, but is formed by embedding a pipe member integrally having a connecting box in the concrete. Therefore, unlike the conventional case, the work of pulling out the rod-shaped member attached to the mold to form the insertion hole at the time of mold removal is eliminated, and the tubular concrete product can be completed only by removing the mold.

Since this pipe member does not need to be pulled out, it is formed to have substantially the same size as the inner diameter of the mold, and therefore both ends thereof can be fixed to the plate member forming the mold. Thereby, when manufacturing a tubular concrete product for a curve, it also functions as a member that connects the plate at the end of the formwork and the inclined partition plate, and prevents the inclined partition plate from moving or twisting. Therefore, it is possible to prevent a gap from being generated. And according to this method,
It is also possible to eliminate the occurrence of defective products due to the twisting and displacement of the inclined partition plate.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

A tubular concrete block 10 shown in FIG.
0 is generally manufactured by disposing the pipe member 21 integrated with the connecting box 22 in the formwork 1, pouring concrete, and removing the formwork 1 after hardening of the concrete.

This tubular concrete block 100 is
It is a casing type having a bottom plate 101, side walls 102, and a top plate 103, and both ends thereof are opened. And
Bottom plate 101 and side wall 102, and top plate 103 and side wall 10
In the corner portion 104 where the two intersect, a tension member (not shown) for connecting the plurality of cylindrical concrete blocks 100 in a state in which the joint end surfaces 105 at both ends thereof are in close contact with each other when, for example, constructing a culvert, is provided. The insertion hole member 2 including the pipe portion 21 material and the connection box 22 which are insertion holes for insertion is embedded, and both end portions 21a thereof are open to the joint end surface 105.

As shown in FIG. 2, the insertion hole member 2 is formed by integrally forming pipe members 21 at both ends of the connecting box 22 so as to communicate with the inside thereof. More specifically, the insertion hole member 2 has a rectangular parallelepiped connecting box 22 having one side surface opened and a circular through hole 22a through which a tension member penetrates, which is formed at both end surfaces in the longitudinal direction. The pipe member 21 is formed by welding so that the central axis of the pipe member 21 passes through the center of the hole 22a. This insertion hole member 2
The total length of the pipe members 21 varies depending on the length of the tubular concrete block 100, and the lengths of the respective pipe members 21 are set so that the connecting box 22 is located at a substantially intermediate point thereof. In the standard type tubular concrete block 100 shown in FIG. 1, the pipe member 21 whose both ends are cut at right angles to the central axis is fixed to the connecting box 22, but the tubular concrete for curves described later is used. In the block 200, at least one end corresponds to the inclination of the joint end surface 205 of the tubular concrete block 200,
It will be cut diagonally.

In the tubular concrete block 100 having such a structure, the insertion hole portion for inserting the tension member is reinforced by the pipe member 21 of the insertion hole member 2, so that the strength of this portion is increased. be able to.

This kind of tubular concrete block 100
The manufacturing process starts with assembling the mold 1.

The formwork 1 includes a bottom plate 11 and a pair of side plates 1.
2, a pair of end plates 13, and a core plate 14. First, a pair of side plates 12 and a pair of end plates 13 are joined to the peripheral edge of the bottom plate 11 to form an outer frame. When joining the end plate 13 to the bottom plate 11, the core plate 14 of the end plate 13 is joined to both ends of the insertion hole member 2 in which the pipe member 21 and the connecting box 22 prepared in advance are integrated. Opening 4
It is fixed to the end plate 13 by using the through hole 13a formed near the corner. For fixing, for example, a female screw portion is formed on the inner surface of the end portion 21a of the pipe member 21, and the end plate 13 is attached to the female screw portion.
It may be performed by screwing a male screw member such as a bolt through the through hole 13a. Then, the core plate 14 is installed between the end plates 13 to complete the assembly of the mold 1 (FIG. 3).

In this embodiment, an unbonded PC is attached to the top plate.
Since the steel material 5 is inserted, both ends of which the male screw is engraved are stretched at the side plate 12 using the nut members 51 and 52. That is, one nut member 51 is attached to one side plate 12 in a penetrating state, and one end portion 5a of the unbonded PC steel material 5 penetrating the anchor plate 54.
Is supported by the nut member 51. Also, a protruding portion 53 called a dog or the like is fixed to the other side plate 12, and the other end member 5b of the unbonded PC steel material 5 is provided with the other nut member 52 by utilizing the internal space of the protruding portion 53. The nut member 52 is screwed and supported by the other side plate 12, and the unbonded PC steel material 5 is stretched. Then, the other nut member 52 is tightened to provide tension between the side plates 12, and the necessary number (two in this embodiment) of unbonded Ps are provided.
In the state in which the C steel material 5 is arranged in the mold 1, fresh concrete is poured into the mold 1. After the casting, in order to increase the filling degree of the concrete C, the formwork 1 is vibrated and the upper surface without the formwork 1 is finished with a trowel (FIGS. 4 and 5).

The curing is carried out in this way, and the mold is removed at the stage when it is confirmed that the compressive strength of the concrete C is, for example, 250 kgf / cm 2 or more. After this demolding, the nut members 51 and 52 at both ends of the unbonded PC steel material 5 are removed, and prestress is introduced into the unbonded PC steel material 5.
That is, after removing the nut member 52, the anchor plate 55 is attached to the recessed portion 100a formed by the protruding portion 53, and each end portion 5a of the unbonded PC steel rod 5 is attached.
The nut 56 is screwed onto 5b. In this case, the other end 5
The nut 56 of b is temporarily installed with a distance to the anchor plate 55. Then, while pulling the other end 5b outward by the hydraulic jack, the nut 56 is fully tightened and fixed (FIG. 6). After that, mark printing or the like is performed, the recessed portions 100a and the like are filled with mortar, and they are moved to a stockyard and stored.

As described above, the insertion hole member 2 is embedded in the concrete C, and since the insertion hole portion for inserting the tension member is formed, it is not necessary to pull out the rod-shaped member or the like after releasing the mold. In addition, it is possible to shorten the process, and it is not necessary to prepare a large work space for pulling out such a rod-shaped member, so that it is possible to manufacture more tubular concrete blocks 100 in a limited work space. It is possible to improve productivity.

Next, another embodiment will be described with reference to FIGS.

In the method of this embodiment, unlike the above-mentioned embodiment, a tubular concrete block 200 for a curve is manufactured, and the mold 1 is provided with an inclined partition plate 16, and at least one of them is used. The joining end surface 205 is formed in a shape inclined with respect to the other joining end surface 206.

Specifically, first, a pair of side plates 12 and a pair of end plates 13 are provided on the periphery of the bottom plate 11 of the standard type tubular concrete block form 1 in the above embodiment.
And are joined to form the outer frame portion. Next, the inclined partition plate 16 is placed between the side plates 12 near the end plate 13 on the far side, and the end plate 1
3, and a supporting rod 17 is interposed between the end supporting member 3 and the front end plate 13 so as to be supported by the insertion hole member 2. In this case, the insertion hole member 2 is fixed to the inner side of the connecting box 22 by cutting the end portion of the pipe member fixed to the front side of the connecting box 22 at a right angle to the central axis corresponding to the end plate 13. The end portion of the pipe member 21 is cut according to the angle of the inclined joint end surface 205, and fixed to the end plate 13 and the inclined partition plate 16 as in the above-described embodiment. Then, the core plate 14 is inserted into the opening of the end plate from the end plate 13 side on the front side, and then the inclined partition plate 16 is penetrated to reach the end plate 13 on the back side. It is fixed to 13 and the assembling of the form 1 is completed.

After the mold 1 is assembled in this way,
Concrete C is poured in the same manner as in the above-mentioned embodiment, and after being vibrated, it is cured for a predetermined period of time and demolded to manufacture a tubular concrete block 200 in which the joint end face 205 is inclined.

In this embodiment, the inclined partition plate 16 is used to manufacture the curved tubular concrete block 200, but unlike the conventional one, the inclined partition plate 16 is made of concrete C. It is supported by a projecting rod 17 from the outside that is not cast, and the inside where the concrete C is cast is formed by the bottom plate 11, the end plate 13, and the side plate 12 by being connected and fixed to the end plate 13 by the insertion hole member 2. It is arranged in a box-shaped frame. That is, the inclined partition plate 16
Is not fixed to the bottom plate 11 or the side plate 12, but is fixed between the both end plates 13 by the insertion hole member 2 and the projecting support rod 17. Therefore, there is almost no risk of deviation from the installation position, it is possible to prevent a gap from being formed between the side plate 12 and the like, it is possible to extremely reduce the probability of defective products, and it is possible to improve the yield. .

The present invention is not limited to the embodiment described above. In the above-described other embodiment, the case of the tubular concrete block 200 in which one joint end surface 205 is inclined has been described, but both joint end surfaces may be inclined.

In addition, the configuration of each section is not limited to the illustrated example, and various modifications can be made without departing from the spirit of the present invention.

[0028]

According to the present invention, since the pipe member is formed by embedding it in concrete to form the insertion hole, it is not necessary to pull out the rod member, and the number of steps can be reduced. The space required for extraction is not necessary, and the space can be effectively used to enable the production of more tubular concrete products. Moreover, since the end of the pipe member is fixed to the formwork,
The inclined partition plate, which is used when manufacturing tubular concrete products whose curved joint end faces are inclined, can be firmly fixed, and the occurrence of defective products due to misalignment of the inclined partition plate can be suppressed. Therefore, the yield can be significantly improved.

[Brief description of drawings]

FIG. 1 is a cylindrical container manufactured in one embodiment of the present invention.
The perspective view which shows a cleat product .

FIG. 2 is a perspective view showing an insertion hole member of the embodiment.

FIG. 3 is a perspective view showing a mold used in one embodiment of the present invention.

FIG. 4 is a process explanatory view for explaining a process of assembling a mold in the manufacturing process of the embodiment.

FIG. 5 is a process explanatory view for explaining a process of placing concrete of the embodiment and applying vibration.

FIG. 6 is a process explanatory view showing a demolding process of the example.

FIG. 7 is a perspective view showing a tubular concrete block manufactured according to another embodiment of the present invention.

FIG. 8 is a perspective view showing a structure of a mold used in the other embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Formwork 2 ... Insertion hole member 21 ... Pipe member 22 ... Connection box

Claims (2)

(57) [Claims] 1. A method for forming a standard type tubular concrete product having both joint end surfaces parallel to each other. A pipe member having the same size and a connecting box for connecting the tension members in the middle is arranged with both ends fixed to the formwork, and concrete is poured into the formwork. A method for producing a tubular concrete product, comprising producing a tubular concrete product with the connecting box and the pipe member being embedded in concrete. 2. The cylinder according to claim 1, wherein the formwork comprises an inclined partition plate for inclining at least one joint end surface, and one end of the pipe member is fixed to the inclined partition plate. Manufacturing method of concrete products.