JP3002741B2 - Formwork for 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 concrete product form for forming a concrete product having a straight hole longer than the opening width such as a through hole.

[0002]

2. Description of the Related Art A concrete product is formed by assembling a box-shaped outer frame including a bottom frame, a side frame, and a spline frame, further mounting a core mold in the outer frame, and placing concrete in the outer frame. After the concrete has hardened, the bottom frame, side frames, end frames, core molds and other form materials are disassembled and removed from the concrete product. However, when removing the form material, it is difficult to remove the form material by moving the form material in parallel to the concrete surface because the friction between the form material and the concrete is large.

[0003] Therefore, when molding a concrete product having holes, a tapered core mold is generally used for a hole that is short (shallow) compared to the opening width (diameter) so as to easily remove the hole. On the other hand, holes that are longer (deep) than the opening width, such as through holes, are formed straight using a cylindrical core such as steel pipe or synthetic resin pipe. The core type is left embedded in the concrete product.

[0004]

As described above, steel pipes,
When a core such as a synthetic resin tube is embedded in a concrete product, a smooth hole can be formed by the core itself, but there is a problem that the material cost is increased. In addition, there is a problem that the core mold embedded in the concrete product interferes with the secondary processing, such that another hole cannot be communicated with the hole formed by the core mold.

The present invention has been made in view of such a conventional problem,
Object of the present invention is to provide a concrete product formwork capable of suitably forming a concrete product having a linear hole longer than the opening width such as a through hole without leaving a core mold embedded therein. It is what it was.

[0006]

SUMMARY OF THE INVENTION The features of the present invention for solving the conventional problems as described above and achieving the intended purpose are as follows.
A concrete product formwork comprising an outer formwork for forming an outer shape of a concrete product, and a core form for forming a linear hole longer than an opening width, wherein the concrete product
Are multiple cables that penetrate the block body in the longitudinal direction.
Can be broken into the insertion hole and the side of each cable insertion hole
Provided with a plurality of recesses for branch holes forming a thin wall.
A bull ground piercing tube block, wherein the core molds the cable insertion hole , and the core mold has rigidity and an inner shape retaining member that retains the shape of the hole. An outer contact member having flexibility and covering the outer peripheral surface of the inner shape retaining member and contacting the concrete, and the inner shape retaining member and the outer contact member are relatively slidable in the longitudinal direction. It was formed in.

The outer peripheral surface of the core type outer contact member is
It is preferable that smooth convex portions and concave portions are formed in a waveform alternately provided in the longitudinal direction .

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 5 to FIG. 7 show a perforated pipe block 20 for laying a cable for electric power or communication such as an electric wire, a telephone line, an optical fiber, etc. underground, and the perforated pipe block 20 is a mold. It is a concrete product molded by.

The porous tube block 20 is composed of a rectangular parallelepiped block main body having a length of about 1 m. Inside the block main body, a plurality of cable insertion holes 22, 22,. It is provided penetrating in the longitudinal direction from the surface to the rear end surface. The cable insertion hole 22 is formed in a cylindrical shape having a cross-sectional area that is sufficient and sufficient to accommodate the cable in order to minimize the cross-sectional area of the block main body, and is longer than the diameter (opening width). It is straight.
Although not shown, the inner peripheral surface of the cable insertion hole 22 is formed in a waveform in which smooth concave portions and convex portions are provided alternately in the longitudinal direction.

A plurality of branch hole recesses 24, 24... Are formed on both side surfaces of the block body.
The branch hole recess 24 is formed in a tapered cylindrical shape having a cross-sectional area similar to that of the cable insertion hole 22 and is formed at a depth that does not reach the cable insertion hole. . As a result, a thin wall 23 is formed between each cable insertion hole 22 and the branch hole recess 24, and the thin wall 23 is crushed when struck by a hammer or the like, so that the cable insertion hole 22 and the branch hole recess are formed. The branch holes communicate with each other between the openings 24.

FIG. 1 shows a mold (in an assembled state) for molding the above-described perforated tube block 20. In FIG. 1, 2 is a bottom frame, 4 and 4 are side frames, and 6 and 6 are end frames. By assembling these, a substantially rectangular box-shaped outer frame corresponding to the block body of the perforated tube block 20 is formed. Are formed. Also, in FIG. 1, 17, 17,... Are recessed cores and are formed in a tapered trapezoid corresponding to the branch hole recesses 24, 24,. , 19 ... are detachably fixed.

In FIG. 1, reference numerals 10, 10... Denote core types for insertion holes. The core 10 for an insertion hole is formed in a cylindrical shape corresponding to the cable insertion hole 22, and as shown in FIG. 2, an inner shape retaining member 12 made of a steel pipe and an outer shape member made of a rubber pipe. The contact member 15 has a double structure. The inner shape-retaining member 12 may be made of a material having rigidity enough to hold a cylindrical shape during concrete casting, and the outer shape-retaining member 15 may be bent to reduce the outer diameter. Any material having flexibility may be used.

That is, the core 10 for an insertion hole has a double structure in which a cylindrical inner shape retaining member 12 is inserted into a cylindrical outer contact member 15. And the outer diameter of the inner shape retaining member 12 are substantially the same and constant in the longitudinal direction so that they can slide in the longitudinal direction. On the other hand, the outer diameter of the outer contact member 15 increases and decreases at regular intervals in the longitudinal direction, and the outer peripheral surface of the outer contact member 15 is formed in a waveform in which smooth convex portions and concave portions are alternately provided in the longitudinal direction. ing. In addition, the pitch P of the waveform on the outer peripheral surface of the outer contact member 15 is about 100 mm, and the depth E (radius difference between the convex part and the concave part) is about 3 mm. Also, the inner shape retaining member 1
2 are provided with pull-out engagement holes 13 at both ends.

The core die 10 for an insertion hole is inserted into the core type mounting holes 7, 7 formed in the end frames 6, 6 at both ends.
It is detachably supported and fixed across both wife frames 6, 6.
The gap between the insertion hole core die 10 and the core die mounting hole 7 is sealed by the packing 9.

In order to form the perforated pipe block 20 by using the thus configured formwork, concrete is poured into an outer formwork comprising the bottom frame 2, the side frames 4, 4 and the end frames 6, 6, After the concrete is hardened, the mold is disassembled and each mold material is removed from the surface of the formed perforated tube block 20.

In order to remove the core 10 for an insertion hole, first, as shown in FIG. 3, only the inner shape retaining member 12 is pulled out from the inside of the outer contact member 15 and removed. Note that the inner shape-retaining member 12 is pulled out by using the pull-out engagement holes 13.
By hooking a hook-shaped pulling tool on the hook, it can be easily performed. Also, a lubricant or the like may be applied to the outer peripheral surface of the inner shape retaining member 12 or the inner peripheral surface of the outer shape contact member 15. Next, as shown in FIG. 5, the outer contact portion 15 is bent inward to reduce the outer diameter, and is detached from the concrete surface and removed.

Accordingly, even if the cable insertion hole 22 to be formed has a linear shape longer than the diameter, the core mold 1 for the insertion hole can be used.
0 can be easily removed, and there is no possibility that it cannot be removed due to friction with concrete. Also,
The inner peripheral surface of the cable insertion hole 22 can be easily formed into a waveform. The core 10 for the removed insertion hole is removed.
Can be used repeatedly, so that the cost can be reduced when a large number of porous tube blocks 20 are manufactured.

As shown in FIG. 8, the cable submerged porous tube 20 formed in this way is 20 to 5 as shown in FIG.
Relay handhole 40 buried at a distance of 0 m,
A number of them are connected in the longitudinal direction and are buried under a sidewalk (or a roadway) so as to communicate between the forties. A branch cable insertion tube 50 is buried between the handhole 40 and the building 100. In burying the perforated pipe blocks 20, 20,..., The cross-sectional area of the block body is minimized, so that the excavation (cutting) range for burying is small.
The construction cost and construction period can be reduced.

By connecting the preformed perforated pipe blocks 20, 20,... To construct a cable laying pipe, steel pipes and synthetic resin pipes are buried and protected by cast-in-place concrete. The construction period can be shortened as compared to (it takes a long time to cure concrete), and the impact on traffic of cars and pedestrians can be minimized. In addition, since the perforated pipe block 20 is made of concrete (made of reinforced concrete) as described above, it is more resistant to impacts than that made of porcelain and can be suitably embedded without being damaged during construction. Since it is cheaper than a synthetic resin pipe, construction costs can be reduced.

The main cable is inserted into each of the cable insertion holes 22 of the perforated tube blocks 20, 20,..., And the inner peripheral surface of the cable insertion hole 22 has a waveform in which smooth concave portions and convex portions are alternately provided. Since it is formed, the friction due to the contact between the cable and the concrete is reduced, and the insertion operation can be performed smoothly. The branch cables are inserted into the branch cable insertion pipes 50, 50,.... In addition, the handhole 40 is formed in a box shape having a size necessary for the insertion work of the cables.

Thus, the perforated tube blocks 20, 2
After the completion of the burying of the handholes 40 and 40 and the laying of the cables underground, if it becomes necessary to lead the cables into the new building 101, first, the building 1
The vicinity of the branch hole concave portion 24 of the porous tube block 20 which is the shortest distance from 01 is dug back.

Next, the thin wall 2 in the branch hole recess 24 is formed.
3 is crushed and removed by hitting with a hammer or the like,
On the side surface of the perforated tube block 20, a branch hole for inserting the cable insertion hole 22 and the branch hole recess 24 is opened. That is, if the steel pipe or the synthetic resin pipe is left embedded as a core, it is difficult to form a branch hole in the side surface of the steel pipe or the synthetic resin pipe after the cable is inserted because the internal cable may be damaged. However, as described above, the core 1 for an insertion hole is used.
0 is removed after the formation of the perforated tube block 20, so that between the cable insertion hole 22 and the branch hole concave portion 24,
The branch hole can be easily opened for communication.

Since the perforated pipe block 20 is made of concrete (reinforced concrete), only the thin wall 23 can be suitably crushed and removed, so that other parts are destroyed as in the case of porcelain. There is no.

Then, a joint made of synthetic resin is attached to the branch hole recess 24 of the perforated tube block 20, and the branch cable insertion tube 51 is connected to the joint. The branch cable insertion pipe 51 is buried between the building 101 and the branch cable insertion pipe 51.
Therefore, even if the building 101 is far from the handhole 40, the excavation area for burying the branch cable insertion pipe 51 can be reduced because the hole from the building 101 to the shortest perforated pipe block 20 can be cut. It is possible to reduce the scale of the work for drawing cables into the simple building 101.

[0026]

As described above, the concrete product mold according to the present invention has a rigid core shape for forming a linear hole longer than the opening width, and has a rigid shape. A dual structure comprising an inner shape-retaining member and an outer contact member that has flexibility and covers the outer peripheral surface of the inner shape-retaining member and contacts the concrete, and the inner shape-retaining member and the outer contact member are relatively By being formed to be slidable in the longitudinal direction, the core mold can be easily removed from the concrete product after the concrete product is formed, by first pulling out the inner shape retaining member and then peeling off the outer contact member. it can. Therefore, since the core mold is not embedded in the concrete product, the core mold can be used repeatedly, and the secondary processing can be easily performed, such as connecting another hole to the hole formed by the core mold. . Then, by providing a convex portion or a concave portion on the outer peripheral surface of the core type outer contact member, a hole having a concave portion or a convex portion on the inner peripheral surface can be easily formed.

Also, the concrete product has a plurality of cable insertion holes penetrating the block body in the longitudinal direction, and a plurality of branch hole recesses forming a breakable thin wall beside each cable insertion hole. Since it is a perforated tube block for burying cables underground, it is possible to form the cable insertion hole suitably only with concrete (without embedding a core mold) so that the cable insertion hole can be easily broken from the branch hole recess. And material costs can be reduced. By forming the outer peripheral surface of the core type outer contact member into a waveform in which smooth convex portions and concave portions are alternately provided in the longitudinal direction, the inner peripheral surface of the cable insertion hole is easily formed into a waveform. The cable can be suitably inserted into the cable insertion hole.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of an embodiment of a concrete product formwork according to the present invention.

FIG. 2 is a longitudinal sectional view of a core type portion in FIG.

FIG. 3 is a longitudinal sectional view showing a detached state of the core-shaped inner shape retaining member of FIG. 2;

FIG. 4 is a vertical sectional view showing a state in which a core-type outer contact member of FIG. 2 is removed.

FIG. 5 is a front view showing a perforated pipe block for laying underground cables formed by the mold of FIG. 1;

FIG. 6 is a vertical sectional view taken along line AA in FIG.

FIG. 7 is a longitudinal sectional view taken along line BB in FIG.

8 is a plan view showing an example of a cable underground laying method using the perforated pipe block of FIG. 5;

[Explanation of symbols]

 2 Bottom frame (outer frame) 4 Side frame (outer frame) 6 Wife frame (outer frame) 7 Core type mounting hole 9 Packing 10 Core type for insertion hole 12 Inner shape retaining member 13 Pull-out engagement hole Reference Signs List 15 outer contact member 17 core for concave portion 19 bolt 20 perforated pipe block (concrete product) 22 cable insertion hole 23 thin wall 24 concave portion for branch hole 40 hand hole 50, 51 branch cable insertion tube 100, 101 building

Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B28B 7/00 B28B 21/00

Claims (2)

(57) [Claims] 1. A concrete product formwork comprising an outer formwork for forming an outer shape of a concrete product and a core form for forming a linear hole longer than an opening width, wherein the concrete product comprises: Penetrate the block body in the longitudinal direction
A plurality of cable insertion holes through which each of the cable insertion holes passes;
Holes forming a thin wall that can be crushed to the side
Cable underground perforated pipe block with
Yes, the core type molds the cable insertion hole
A is, the core die has an inner shape retaining member for retaining the shape of the hole rigid, outer contact by covering the outer peripheral surface of the inner shape retaining member has flexibility in contact with the concrete A mold for a concrete product, comprising: a member; and wherein the inner shape-retaining member and the outer contact member are formed so as to be relatively slidable in the longitudinal direction. 2. The outer peripheral surface of the core type outer contact member is smoothed.
Kana convex portions and concave portions are alternately provided in the longitudinal direction.
The concrete product formwork according to claim 1 formed .