JP2522636B2 - 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 above-mentioned sewer, etc., but for tubular concrete blocks used for such a purpose, There are a straight type, that is, a standard type in which both joint end faces are parallel, and a curved type, that is, one in which at least one joint end face is inclined with respect to the other joint end face. Then
Curved tubular concrete blocks are smaller in number than 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. Molding is too uneconomical. 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.

[0003]

However, such a partition plate is in a state of being inclined with respect to the end surface of the mold for molding a standard type tubular concrete block at various angles in the space inside the mold. Since it must be arranged so that there are no gaps, it is difficult to manufacture it, and mounting on the formwork is also slightly different depending on the angle, so always place it in the same state without forming a gap. Is difficult. Further, since such an inclined partition plate is often twisted or misaligned, there is a problem that the rate of defective products is high.

Therefore, the means shown in FIGS. 3 to 8 can be considered as effective means. More specifically, in the tubular concrete block 100, roughly, the reinforcing material 2 is arranged in the formwork 1, the concrete C is cast, and after the concrete C is hardened, the formwork 1 is removed. The semi-finished product 3 is molded, and the part of the semi-finished product 3 where the reinforcing material 2 is not embedded (hereinafter,
It is manufactured by cutting off the unnecessary portion 31) with a concrete cutter. FIG. 8 shows the unnecessary portion 31 and the finished product 4 that have been cut off. In manufacturing, the steps up to the production of the semi-finished product 3 are basically the same as the steps of manufacturing the standard type, except that the deformed reinforcing material 2 is arranged in the mold 1. The steps will be described below in order.

First, the mold 1 is assembled. This formwork 1
Basically, it is formed of a thin plate similar to the standard type when using a conventional unbonded PC steel material, and includes a bottom plate 11, a pair of side plates 12, a pair of end plates 13, and a core plate 14. Become. 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 a box-shaped frame. Next, the reinforcing material 2 made of rebar is placed in the middle of the bottom plate 11 in the left-right direction, and the end portion which is not inclined in the longitudinal direction is formed near one edge of the bottom plate 11 at its edge. Arrange in parallel. The reinforcing member 2 has a size such that the reinforcing bar is arranged substantially at the center in the thickness direction of the bottom plate 42, the top plate 43, and the left and right side walls 44 of the finished product 4, and the other joint end surface 41 b of the finished product 4 is provided. A plurality of reinforcing bars 21 and vertical bars 22 are welded at predetermined intervals in accordance with the shape of one joint end surface 41a inclined with respect to each other to form a double-structured cage. Then, for example, it is placed on a ceramic spacer CS arranged on the bottom plate 11 and arranged so as to keep a constant distance from the bottom plate 11, and the core plates 14 and the side plates 12 are also arranged. In order to make the distance constant, in other words, the reinforcing member 2 is fixed to the inside and outside of the reinforcing material 2 so that the reinforcing material 2 penetrates through the center of the core plate 14 and the side plate 12. . After disposing the reinforcing material 2, the core plate 14 is installed between the end plates 13 in a state of penetrating the inside of the reinforcing material 2, and the assembly of the mold 1 is completed.

In this embodiment, since the unbonded steel material 5 is put in the top plate portion, 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 the anchor plate 54
The one end portion 5a of the unbonded PC steel material 5 which penetrates through is supported by the nut member 51. Also, the other side plate 1
A protruding portion 53 called a wanco or the like is fixed to 2, and the other nut member 52 is screwed to the other end portion 5b of the unbonded PC steel material 5 by utilizing the internal space of the protruding portion 53, and The nut member 52 is supported by the other side plate 12, and the unbonded PC steel material 5 is stretched. Then, the other nut member 52
Tensioning is provided between the side plates 12 by tightening, and the required number (two in this embodiment) of unbonded steel materials 5 are arranged in the mold 1 and then the concrete is poured into the mold 1. To do. After the casting, in order to increase the filling degree of the concrete C, the mold 1 is vibrated and the upper surface without the mold 1 is finished with a trowel (FIGS. 3 and 4).

The curing is carried out in this manner, 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. 5).

The tubular concrete block thus obtained by demolding is a semi-finished product 3 of the same shape as the standard type, and the joint end faces 32 of both of them are parallel. Therefore, the unnecessary portion 31 in which the reinforcing material 2 is not embedded is cut by a concrete cutter in parallel with the inclination of the end portion of the reinforcing material 2 to complete the tubular concrete block 100 having at least one inclined joint end surface 41a. Product 4 is manufactured. In the cutting, the position of the reinforcing material 2 is specified from the outer shape of the semi-finished product 3 so that the cuts of the bottom plate 42, the top plate 43, and the left and right side walls 44 are flush with each other, and the outside of the end portion of the reinforcing material 2 is identified. It is performed so that a predetermined thickness remains. Since the concrete cutter only cuts concrete C,
It can be easily cut, and since the reinforcing material 2 is not embedded in the removed unnecessary portion 31, it can be easily crushed. After cutting, the finished product 4 is subjected to mark printing or the like, filled in the recess 100a or the like with mortar, and moved to a stockyard for storage.

As described above, the standard type mold 1 is used to manufacture the semi-finished product 3 having the same shape as the standard type, and the unnecessary portion 31 is cut out from the semi-finished product 3 to form a desired curve cylinder. Since the concrete block 100 is manufactured, the formwork 1
It is no longer necessary to use a dedicated partition, nor is it necessary to use a partition plate. Therefore, the dedicated mold and core plate 1
It is possible to suppress an increase in cost due to the use of an inclined partition plate having an opening having a shape through which the through hole 4 penetrates, and the concrete C flows out from the gap formed in the case of such an inclined partition plate or the inclined partition plate. It is possible to reduce the probability that the outer shape will change due to the displacement of the arrangement position of the item 1 and the like, resulting in a defective product, and it is possible to improve the yield.

However, according to such a method, although the conventional problems can be solved, the concrete block 10
The smaller 0 is for the standard type, the larger is the unnecessary portion 31 to be cut off, which causes a new problem that waste is increased. The present invention aims to solve such a problem.

[0011]

In order to achieve the above object, the present invention takes the following measures. That is, the method for manufacturing a tubular concrete product according to the present invention is a form for molding a standard type tubular concrete product in which both joint end faces are parallel, at least one joint end face with respect to the other joint end face. And a reinforcing material for a tubular concrete product that is inclined, and is disposed parallel to the end surface at an internal position separated from the end surface by a distance approximately equal to the larger depth dimension of the reinforcing material. A partition plate is provided, and concrete is cast in the area containing the reinforcing material in the area partitioned by the partition plate in the mold to form a semi-finished product that is smaller than the standard type tubular concrete product. , A tubular concrete product in which at least one of the joint end faces is inclined with respect to the other joint end face by cutting off a portion of the semi-finished product in which the reinforcing material is not embedded by a cutter. And characterized in that the elephants.

Further, in the present invention, the reinforcing material may include a reinforcing bar, and further, the reinforcing material may include a PC steel material for introducing prestress.

[0013]

According to the present invention, the arrangement of the reinforcing material is designed for a curve, that is, at least one joint end surface is inclined with respect to the other joint end surface, and the reinforcement material is a standard type. It is placed in the mold of. This arrangement work is
It may be performed according to the case of using a partition plate. At this time,
By placing a partition plate that is parallel to the end of the standard type formwork, the substantial total length of the formwork is shortened, and a reinforcing material is placed in the space partitioned by the partition plate. Install and pour concrete to obtain a semi-finished product smaller than the standard type. Then, a predetermined position of this semi-finished product is cut by an appropriate cutter to complete a tubular concrete block for a curve. Since the reinforcing material is not buried in the removed unnecessary portion, it can be easily crushed and effectively used.

In this way, when manufacturing a product having a relatively shorter length than that of the standard type, it is manufactured so that unnecessary parts are reduced as much as possible, even though the standard type mold is used. can do. In particular, since the position where the partition plate is disposed is separated from the end face of the mold by a distance approximately equal to the larger depth dimension of the reinforcing material embedded, the unnecessary portion to be cut can be minimized.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. The same parts as those in FIGS. 3 to 8 are designated by the same reference numerals and the description thereof will be omitted. In the method of this embodiment, a partition plate (hereinafter, parallel partition plate) 7 having a shape different from the conventional one is used in order to reduce the unnecessary portion 31 to be cut as much as possible and reduce the amount of concrete used. However,
The parallel partition plate 7 is for shortening the length dimension of the mold 1, and is arranged in the mold 1 in parallel with the end plate 13 of the mold 1. Therefore, its shape is the same as that of the end plate 13, and it can be easily manufactured.

Similarly to FIGS. 3 to 8, 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 a box-shaped frame, in which the reinforcing bars are formed. Made of reinforcing material 2,
Bars are arranged in the left-right direction at a substantially central portion of the bottom plate 11 and in the longitudinal direction in a state in which end portions which are not inclined near one edge of the bottom plate 11 are parallel to each other. Next, the parallel partition plate 7 is arranged at a position separated from the end of the reinforcing member 2 on the inclined side by a predetermined distance in consideration of the thickness of the finished product 4. The parallel partition plate 7 is a surface not facing the reinforcing material 2, that is, the end plate 13
A plurality of protruding rods 8 of the same length, which serve as spacers, are arranged between the surface opposed to and the end plate 13 and arranged at a desired position. After that, so as to penetrate the inside of the reinforcing member 2,
Further, a core plate (not shown) is arranged between the end plates 13 through the parallel partition plates 7, and the unbonded steel material 5 is mounted in the same manner as in the above-mentioned embodiment to complete the preparation of the mold 1.

After the formwork 1 has been prepared, FIG.
Similarly to FIG. 8, concrete C is poured, and then the form 1 is removed to obtain a semi-finished product 3A shorter than the standard type and similar in shape to the standard type. When placing concrete C,
Although pressure is applied to the parallel partition plate 7 from the concrete C, since the parallel partition plate 7 is arranged in parallel with the end plate 13 and supported by the projecting rod 8, the pressure is evenly applied to the whole and unevenly distributed. Since it is not pushed, the position is not displaced and an unnecessary gap is not formed. The obtained semi-finished product 3A has a length dimension slightly larger than the longest dimension of the reinforcing material 2, and as in the above-mentioned embodiment, from the inclined end portion of the reinforcing material 2 to the end of the semi-finished product 3A. The unnecessary portion 31a having a rectangular prism shape with a trapezoidal cross section is not formed up to the portion, but the unnecessary portion 31a having a substantially triangular prism shape is formed. It is smaller than the example. Then, the unnecessary portion 31a of the semi-finished product 3A in which the reinforcing material 2 is not buried is cut by a concrete cutter to obtain a tubular concrete block 100 in which one joint end surface 41a is inclined.

As described above, in the manufacturing method of this embodiment,
The parallel partition plate 7 is used to reduce the substantial size of the formwork 1. Since the parallel partition plate 7 is arranged in parallel with the end plate 13, it is difficult to open a gap and it can be arranged very easily. Moreover, the unnecessary portion 31a cut by the concrete cutter is reduced by the size between the end plate 13 and the parallel partition plate 7, that is, the size of the portion actually used as the mold 1 is reduced. Therefore, the amount of concrete to be used can be reduced, and the unnecessary portion 31a that has been cut off is also small, and since the reinforcing material 2 is not buried, the crushing process can be easily performed.

The present invention is not limited to the embodiment described above. In the above embodiment, the tubular concrete block 100 in which one joint end face 41a is inclined
Although the case has been described, both joint end faces may be inclined. Besides, the configuration of each unit is not limited to the illustrated example, and various modifications can be made without departing from the spirit of the present invention.

[0020]

INDUSTRIAL APPLICABILITY As described in detail above, the present invention uses a standard type mold to manufacture a tubular concrete block in which at least one joint end surface is inclined, so that the inclined joint is achieved. There is no need to worry about problems such as gaps or displacement of the formwork at the part like the one that uses a partition plate that matches the end face, and the cost of the formwork such as a dedicated formwork. Does not become large, and a tubular concrete block having a desired inclined joint end surface can be easily manufactured. Further, it is possible to eliminate defective products caused by twisting or positional deviation of the partition plate, as compared with the case where the inclined joining end surface is produced by the inclined partition plate.

In addition, even if such a standard type mold is used, when the concrete is smaller than the standard type, a partition plate arranged in parallel with the end plate is used to make a substantial mold. Since the frame area can be limited to a small size,
It is possible to reliably reduce the amount of concrete used.

[Brief description of drawings]

FIG. 1 is a perspective view of a semi-finished product according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a state in which an unnecessary portion of the embodiment is separated.

FIG. 3 is a process explanatory view showing a process of assembling a conventional mold.

FIG. 4 is a process explanatory view showing a process of placing concrete of the conventional example and applying vibration.

FIG. 5 is a process explanatory view showing a demolding process of the conventional example.

FIG. 6 is a perspective view showing a part of the entire configuration of the conventional example before being removed from the mold.

FIG. 7 is a perspective view showing a semi-finished product of the conventional example.

FIG. 8 is a perspective view showing a state in which an unnecessary portion of the conventional example is separated.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Formwork 2 ... Reinforcement material 3 ... Semi-finished product 4 ... Finished product 5 ... Unbonded steel material 7 ... Partition plate 41a ... One joining end surface 41b ... The other joining end surface

Claims (3)

(57) [Claims] 1. A tubular concrete product in which at least one of the joining end faces is inclined with respect to the other of the joining end faces in a form for molding a standard type tubular concrete product having both joining end faces parallel to each other. Reinforcement material is installed and
For a distance approximately equal to the larger depth dimension of the
Is arranged in parallel to the end face at an internal position away from the end face of
A partition plate was provided and it was partitioned by the partition plate inside the formwork .
Concrete is poured into the area containing the reinforcing material to form a semi-finished product that is smaller than the standard type tubular concrete product, and then the part of the semi-finished product in which the reinforcement material is not embedded is cut with a cutter. A method for producing a tubular concrete product, characterized in that at least one of the joining end faces is cut away by the above method to produce a tubular concrete product which is inclined with respect to the other joining end face. 2. The contract, wherein the reinforcing material includes a reinforcing bar.
The method for producing a tubular concrete product according to claim 1 . 3. The reinforcing material is a PC steel material for introducing prestress.
The method for producing a tubular concrete product according to claim 1, further comprising :