JP4553600B2 - Method for manufacturing split concrete pipe - Google Patents

Description

  The present invention relates to a method for manufacturing an assembling-type concrete split concrete pipe suitable for a large diameter propulsion method of 3 m or more.

Conventionally, as a method of manufacturing a concrete pipe, there is a method in which an outer cylindrical formwork and a wife formwork are rotated on a turntable, compacted using centrifugal force, and integrally formed.
However, when the diameter of the concrete pipe becomes a large diameter of 3 meters or more, the manufacturing equipment and the manufacturing place cannot be secured, and the actual manufacturing becomes very difficult. In addition, even if the problem of manufacturing equipment and cost is solved, it is impossible to transport concrete pipes with a large diameter of 3 meters or more to the site due to road conditions and on-vehicle dimensions, or even if it can be transported, it has a high transportation cost. The burden is forced.
Therefore, the applicant previously proposed an invention of a split-type concrete pipe that can be used in advance by manufacturing a plurality of divided bodies obtained by dividing a concrete pipe in the axial direction, bringing them into a construction site and assembling them into a cylindrical shape. .

However, in the above-described divided concrete pipe, if there is a perfectly smooth surface and perfect parallelism, theoretically, if the joining surfaces of the divided bodies are joined together, they will contact each other even if manufactured separately. It should be. However, in reality, since the entire divided body is twisted or partially distorted, a gap is generated between the joint surfaces of both divided bodies. The gap formed on the joint surface not only causes deterioration of the water stoppage, but also causes a load on the concrete and cracks due to local stress as well as uneven distribution of the load.

In order to solve the above-described problems, the method for manufacturing a split concrete pipe according to the present invention is a manufacturing method of a split concrete pipe configured by a plurality of split bodies obtained by splitting a cylindrical concrete pipe along the axial direction. In the method, the arc-shaped outer mold frame surface and the inner mold frame surface that are vertically arranged at a certain distance are arranged to face each other, the side end surfaces of the both mold frame surfaces are closed with a face plate surface, and the mold Forming a pre-divided body in which concrete is filled in the frame to form a joint surface on the side end surfaces of the two mold frame surfaces, demolding the mold and the face plate surface of the hardened pre-divided body, and arc-shaped pre-dividing The outer mold frame surface and the inner mold frame surface are arranged opposite to each other on the joining surface side of the vertically divided preceding divided body, and the outer mold frame is used. the circumferential ends of the bets in the mold is covered with a bonding surface of the leading divided body forms a space that is open upward, the leading divided Characterized by forming the trailing divided body filled with concrete in a mold frame having an open upper utilized as end plate faces the joint surface of the.

  Moreover, the manufacturing method of the split-type concrete pipe of this invention is characterized by embedding a joint tool in the inside and outside of the joint surface of the said preceding division body and the said subsequent division body, and shape | molding both division bodies.

Moreover, the manufacturing method of the split-type concrete pipe of this invention is characterized by embedding the said joint tool in the said subsequent division body previously, and shape | molding it.

The method for manufacturing a split concrete pipe according to the present invention is to form a subsequent divided body by using the joint surface of the preceding divided body constructed in advance as the end face of the subsequent divided body. Thus, when assembled in a cylindrical shape, there is no gap between the joint surfaces, and this enables reliable and smooth construction.
In addition, by assembling the joint tool in advance and placing it in the concrete before placing the concrete of the succeeding divided body, it is possible to completely match the plurality of joint tools while arranging them.
The sealability is improved, and cracks and hooks due to the joint can be prevented.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<1> Overall Configuration FIG. 1 shows a preceding divided body 10a of a split-type concrete pipe 10 formed by using the manufacturing method of the present invention, and FIGS. 2 and 3 show a transverse sectional view and a longitudinal sectional view thereof.
The split concrete pipe 10 formed in this example is a cylindrical body having a cylindrical shape, and is divided into a plurality of divided bodies 10a and 10b along the longitudinal (axial) direction, and the joined bodies 10a and 10b. It comprises a plurality of joint tools 20 that connect the surfaces 11a, 11a, 11b, and 11b.
Hereinafter, details of each part will be described.

<2> Divided bodies The divided bodies 10a and 10b are formed by dividing the cylindrical concrete pipe 10 in the axial direction into a circular arc shape. Various reinforcing materials such as reinforcing bars are embedded in the divided bodies 10a and 10b. Moreover, although the material is concrete, resin concrete, hard resin, and a sintered body of various industrial wastes may be used in addition to concrete, and these materials are formed into a predetermined shape using vibration or centrifugal force.

  The divided bodies 10a and 10b of the concrete pipe 10 are not limited to the two-divided form as shown in the figure, but may be divided into three or more. In addition, the number of divisions can be appropriately set according to the diameter of the concrete pipe 10.

When the concrete pipe 10 is used by being added in the axial direction, the male joint 12 and the female joint 13 can be formed at both ends of the pipe body, that is, at the end portions in the axial direction of the divided bodies 10a and 10b.
As shown in FIG. 1, the male joint 12 formed at the lower end of the concrete pipe 10 is formed integrally with an outer diameter that is smaller than the outer diameter of the housing body and protrudes from the body of the concrete housing in the axial direction. On the other hand, the female joint 13 formed at the upper end of the concrete pipe 10 is formed integrally with an inner diameter larger than the inner diameter of the main body of the frame and protruding in the axial direction from the main body of the concrete case.
The axial length forming the female joint 13 is set to be shorter than the protruding length of the male joint 12 and can be fitted to the adjacent concrete pipes 10.

In addition, the cross-sectional shape of the concrete pipe 10 is not limited to a circular shape, and the joint is not limited to the illustrated form, and it is needless to say that various known joint structures can be applied.

<3> Joint tool The joint tool 20 is arranged on both side end faces parallel to the axial direction of the two divided bodies 10a and 10b, that is, the joint surfaces 11a, 11a, 11b and 11b, and is used for joining the two divided bodies 10a and 10b. .
A plurality of joint tools 20 are embedded inside and outside the joint surfaces 11a, 11a, 11b, and 11b with a certain interval in the axial direction (FIGS. 3 and 4).
In this example, as means for connecting the two divided bodies 10a and 10b, a pair of connecting boxes 21a and 21b and a connecting wedge body 22 which is a connecting member for connecting the connecting boxes 21a and 21b are provided. The case of connecting in combination will be described.

The connecting boxes 21a and 21b have a C-shaped cross section, and are embedded across the joint surfaces 11a and 11b and the inner and outer peripheral surfaces of the respective divided bodies 10a and 10b, and internal spaces having a substantially T-shape are respectively formed on the inner and outer circumferences. It is exposed on the surface.
The connecting wedge body 22 is a connecting body having an H-shaped section or an I-shaped section in which bulged portions 221 and 221 are formed at both ends, and a taper with a constant gradient is formed on the opposing surfaces of the facing bulged portions 221 and 221. By being inserted between the internal spaces of the connecting boxes 21a and 21b from the side, the pair of connecting boxes 21a and 21b can be connected while being close to each other.

  In this example, when the two divided bodies 10a and 10b are connected, they are connected on both the inside and outside of the joint surfaces 11a and 11b. This is to make it possible to face each other when the tensile force and the compressive force are applied to the inside and the outside of the joint surfaces 11a and 11b of both divided bodies 10a and 10b.

In addition, the connection boxes 21a and 21b formed on the inner side of each side end surface and the connection boxes 21a and 21b formed on the outer side may be formed at the same position in the axial direction, but FIG. As shown in 3), it is desirable to shift the position in the axial direction to form a staggered pattern. This is to improve the dispersibility of the external force by avoiding stress concentration in one cross section.
Furthermore, in order to ensure a high water-stopping property at the connecting portion, a coating film having a sealing function such as an epoxy resin is formed over the entire area of the joint surfaces 11a, 11a, 11b, 11b or the formation range of the female joint 13.

<4> Formwork The formwork 30 is for forming the divided bodies 10a and 10b. The formwork 30 includes inner mold frames 31a and 31b for forming the inner formwork surfaces of the divided bodies 10a and 10b, and the divided bodies 10a and 10b. It comprises outer mold frames 32a and 32b for molding the outer mold surface and wife mold frames 33a and 33a for molding the joint surfaces (face plate surfaces) of both mold frame surfaces (FIG. 1).

A known mold as shown in FIG. 1 can be used for the outer mold 32a and the inner mold 31a, and is selected according to the shapes of the divided bodies 10a and 10b.
As the wife molds 33a and 33a of the preceding divided body 10a, a mold having a plane that forms the joint surface 11a is used.

On the other hand, the same formwork as that of the preceding divided body 10a can be used for the outer and inner circumferential molds 31b and 32b of the divided body 10b to be constructed following. However, the joint surface 11a of the preceding divided body 10a is used as a mold frame for the wife mold frame of the succeeding divided body 10b. The connecting wedge body 22 and the connecting box 21b facing each other are set in advance in each connecting box 21a of the preceding divided body 10a after demolding to form a mold. In this way, the joint surface 11a of the preceding divided body 10a from which the plurality of joint tools 20 protrudes is used as a wife mold (FIG. 5).
The shapes of the outer mold frame, the inner mold frame, and the wife mold frame are not necessarily limited to the above.

<5> Manufacturing method Next, the manufacturing method of the concrete pipe which concerns on this invention is demonstrated.

The inner mold frame 31a and the outer mold frame 32a are placed vertically and are arranged at a predetermined interval. The protruding part of the inner mold 31a is arranged at the upper part, and the protruding part of the outer mold 32a is arranged at the lower part (FIG. 3).
The connecting boxes 21a are arranged in a staggered manner inside and outside the portion forming the joining surface 11a. It is preferable to place a temporary member having a shape obtained by cutting the connecting wedge body 22 in half so that concrete does not enter inside the connecting box 21a. Each connection box 21a is arranged so that the connection wedge body 22 can be attached to and detached from the inner and outer peripheral surfaces after demolding. Thus, the part excluding the upper part is surrounded by the formwork.

  Reinforcement inside the space surrounded by the formwork. This bar arrangement work may be performed before setting the formwork, and in this case, it may be arranged in advance in either the inside or outside formwork. Similarly, when a steel plate outer shell is provided on the outer periphery of the divided body 10a, it may be arranged in advance inside the mold before placing concrete.

  Concrete is cast inward from an arcuate gap formed at the upper end between the inner mold 31a and the outer mold 32a. After filling the internal voids with concrete, it is left to solidify for the required time.

  After a certain period of time, remove the formwork. The mold is removed except for the inner mold 31a among the three types. When the wife molds 33a and 33a are removed, the connecting boxes 21a arranged at regular intervals are exposed on the joint surfaces 11a and 11a of the preceding divided body 10a. The temporary member is removed from each connection box 21a, and the connection wedge body 22 and the connection box 21b are arranged.

The inner mold frame 31b having the same shape is placed back-to-back on the planar portion of the inner mold frame 31a. Thereafter, the outer mold 32b is assembled in the same manner as described above (FIG. 5). When the outer mold frame 32b is arranged, the end of the outer mold frame 32b in the circumferential direction covers the end of the preceding divided body 10a.
In this way, the inner mold frame 31b, the outer mold frame 32b, and the joint surfaces 11a and 11a of the preceding divided body 10a form a space that opens upward. Concrete is filled here and the divided body 10b is shape | molded. That is, the bonding surfaces 11a and 11a of the preceding divided body 10a are used for forming the bonding surfaces 11b and 11b of the trailing divided body 10b. The concrete to be filled is spread over the joining surfaces 11a and 11a that are uneven, and the joining surfaces 11b and 11b of the succeeding divided body 10b are formed using the joining surfaces 11a and 11a of the preceding divided body 10a as a mold. For this reason, the joint surfaces 11a and 11b separated after curing have a shape that can be fitted. That is, the joining surface 11a of the preceding divided body 10a does not necessarily have to be smooth, and may be formed almost in parallel with the axial direction of the concrete pipe 10. Even if there are some irregularities on the joint surfaces 11a and 11a of the preceding divided body 10a, the joint surfaces 11b and 11b that face each other using the joint surfaces 11a and 11a as molds are formed. It does not occur and can be joined (FIG. 6).
Moreover, since each division body 10a, 10b is what is once decomposed | disassembled and molded in the factory where the manufacturing environment was prepared, it can manufacture with high quality.

When concrete is placed behind the scenes, an insulating layer is provided on the joint surfaces 11a and 11a excluding the joint tool 20. In this way, the placed concrete embeds only the joint tool 20 so as not to be integrated with the joint surfaces 11a and 11a of the preceding divided body 10a.
After placing and filling the concrete and letting it stand for the required time, it is demolded.
After removing the outer mold frame 32b and the inner mold frames 31a, 31b, the connecting wedge bodies 22, 22,... Are removed from each joint tool 20 located on the joint surfaces 11a, 11b, and the divided bodies 10a, 10b are divided into two. To do.

The divided bodies 10a and 10b are loaded onto a required transport vehicle together with the connecting wedge body 22, and are carried out to the site.
As described above, the split-type concrete pipe 10 manufactured by the method of the present invention has a particularly high laying depth and a large laying depth because the joint surface is completely fitted even if the joint is twisted and distorted. It is useful for concrete pipes that are molded to the thickness of the body with the diameter.

In the above, the case where the male joint 12 and the female joint 13 are formed at both ends of the concrete pipe 10 has been described. However, the present invention is not necessarily limited to this form, and the shape of the form is also arbitrary accordingly. It can be.

<6> Other Embodiments The method for manufacturing the cylindrical concrete pipe 10 has been described above, but the cross-sectional shape of the concrete pipe 10 is not particularly limited, and may be, for example, an ellipse or a square. Even in the case of this form, like the above-described embodiment, the concrete pipe is divided in the axial direction, the joint tool is embedded in the joining surface of the preceding divided body to be formed in advance, and this joined surface is used as the wife mold of the succeeding divided body. By using it as a frame, it is possible to form a concrete pipe that is not twisted or partially distorted in the entire divided body at the time of joining on site.

The perspective explanatory view of the preceding division object concerning the present invention. The cross-sectional view of the preceding divided body during molding. III-III arrow line view of FIG. The enlarged detail drawing of the joint surface of a preceding division body. The figure which showed the formation process middle part of the subsequent division body. The enlarged view of the junction surface of a preceding division and a subsequent division.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Concrete pipe 10a ... Predecessor division body 10b ... Subsequent division body 11 ... Joint surface 20 ... Joint tool 31a, 31b ... Inner mold frame 32a, 32b ... Outer mold Frame 33a ... wife formwork

Claims (3)

In the method for manufacturing a split concrete pipe, comprising a plurality of split bodies obtained by splitting a cylindrical concrete pipe along the axial direction,
Arranging the arc-shaped outer mold surface and the inner mold surface facing each other vertically with a certain distance,
The side end surfaces of the two mold surfaces are closed with the end plate surface,
Molding the concrete into the mold and forming a preceding divided body having a joint surface on the side end surfaces of the two mold surfaces ,
Demolding the formwork and the end face of the hardened prior division,
Using arc-shaped preceding divisions and arc-shaped outer and inner mold surfaces,
The outer mold frame surface and the inner mold frame surface are arranged opposite to each other on the joining surface side of the vertically divided preceding divided body,
Covering the circumferential ends of the outer mold frame and the inner mold frame with the joint surface of the preceding divided body to form a space opened upward,
Using the joint surface of the preceding divided body as a face plate surface , filling the concrete into the mold that opened upward, and forming the subsequent divided body,
A method of manufacturing a split concrete pipe.   In the method for manufacturing a split concrete pipe according to claim 1, characterized in that both split bodies are formed by embedding joint tools inside and outside the joint surfaces of the preceding split body and the subsequent split body. A method of manufacturing a split concrete pipe. 3. The method for manufacturing a split concrete pipe according to claim 2 , wherein the joint tool is embedded in the succeeding divided body in advance and formed.

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