JPH071439Y2 - Concrete formwork support pipe for construction or civil engineering - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a concrete formwork support pipe made of fiber reinforced plastic for construction or civil engineering.

[Prior art and its drawbacks] When placing concrete in construction or civil engineering, the concrete formwork is assembled by a support pipe called a flap material. As this support pipe, iron and aluminum pipes are generally used, but iron pipes have the drawback of being heavy and corroded by water, etc. It has the drawback of being easy to do. Therefore, recently, those made of fiber reinforced plastic have come to be used.

This plastic support tube is lightweight, resistant to corrosion,
In addition to the advantage that concrete is unlikely to adhere, it has the advantage of having a predetermined mechanical strength because it is reinforced with reinforcing fibers such as glass fibers.

However, the above-mentioned fiber-reinforced plastic support tube has a drawback in that the end portion is cut off and opened, so that concrete penetrates through the end opening and solidifies to become very heavy. Further, when used in a place where water is covered, water enters the inside of the support pipe, and water flows out from the inside during handling, which hinders handling. In addition, the end of the support tube may be damaged,
It may have cracked.

[Challenges for devising]

The object of the present invention is to solve the drawbacks of the conventional concrete formwork support pipe made of fiber reinforced plastics for construction or civil engineering work, concrete and water do not enter the inside of the pipe, and the pipe end is not damaged or cracked. , To provide a concrete formwork support pipe made of fiber reinforced plastic for construction or civil engineering work.

[Means for Solving the Problems]

The present invention has been made to achieve the above object, and a concrete formwork support pipe made of fiber reinforced plastic for construction or civil engineering according to the present invention has an end opening of the support pipe closed by a plastic stopper. This stopper
It has a fitting portion that is tightly fitted and adhered to the end portion of the support tube, and a flange portion that is integrally formed on the outer end portion of this fitting portion, and is recessed toward the support tube at the outer end portion of the hermetic stopper. It is characterized in that a recess is formed and the outer peripheral surface of the recess is tapered.

Here, it is preferable that the fitting portion of the hermetic plug is formed in a tubular shape, the outer end portion thereof is closed by the closing bottom portion, and the concave portion is formed on the outer end surface of the closing end portion.

Further, the angle between the outer peripheral surface of the recess and the outer end surface of the stopper is 20 to 70.
It is desirable that the angle is °.

Further, it is desirable that the fitting portion of the sealing plug has a large number of shallow grooves extending in the longitudinal direction of the support tube on the outer peripheral surface thereof.

〔Example〕

 Next, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a longitudinal section of an end portion of a concrete formwork support pipe 1 for construction or civil engineering work and a hermetic stopper 2 fitted in an opening of the support pipe end portion.

The support tube 1 is formed as a fiber-reinforced plastic rectangular pipe and has a three-layer structure including an intermediate layer 3, an inner layer 4 and an outer layer 5. The intermediate layer 3 of the support tube 1 is formed by integrally binding reinforcing fibers with a thermosetting resin. An unsaturated polyester resin is preferable as the thermosetting resin. Further, as the reinforcing fiber, in order to improve the rigidity of the reinforced plastic pipe, it is preferable to use a long fiber bundle, and as the fiber, polyester, nylon,
It is preferable to use organic synthetic fibers such as vinylon, polyethylene, polypropylene and aromatic polyamide, and inorganic fibers such as glass fibers and carbon fibers.

The inner side and the outer side of the intermediate layer 3 are covered with the inner layer 4 and the outer layer 5 made of a thermoplastic resin. As the thermoplastic resin forming the inner layer 4 and the outer layer 5, those having a chemical affinity with the thermosetting resin (for example, unsaturated polyester resin) which is the matrix of the intermediate layer 3 are used. As, acrylonitrile-butadiene-styrene resin (ABS resin), acrylonitrile-
Styrene resin (AS resin), acrylonitrile-acrylic-styrene resin (AAS resin), polystyrene resin (P
S resin), polycarbonate resin (PC resin) and the like.

The concrete formwork support pipe 1 is manufactured, for example, as follows. First, the thermoplastic resin forming the inner layer 4 is first
After being extruded into a pipe shape by the extruder of No. 3 and continuously molded and solidified, the liquid thermosetting resin-impregnated reinforcing fibers constituting the intermediate layer 3 are continuously extruded onto the outer periphery of the continuously extruded inner layer pipe-shaped material. It is coated and shaped into a predetermined cross-sectional shape, and the thermoplastic resin forming the outer layer 5 is further coated by a second extruder. The pipe-shaped material continuously molded in this way is immediately put in cooling water, the thermoplastic resin of the outer layer 5 is cooled and solidified, and then passed through a hot water tank arranged on the same line to form an intermediate tank. The support tube of the present invention can be obtained by heating and curing the thermosetting resin of No. 3. The dimensions of the support tube 1 are, for example, 50 mm square in outer dimension, 0.5 mm in thickness of the outer layer 5, 2.7 mm in thickness of the intermediate layer 3, and 1.8 m in thickness of the inner layer 4.
m.

The fiber-reinforced plastic support tube 1 having the three-layer structure has mechanical properties such as compressive strength, bending fracture strength, bending rigidity, etc., which sufficiently withstands use as a concrete formwork supporting tube.
Since the outer layer 5 that constitutes a part of the support tube 1 is made of a thermoplastic resin, it has excellent corrosion resistance unlike iron pipes, etc., and unlike aluminum pipes, etc., even if concrete adheres during construction, it is easy. It can be peeled off and removed.

The end opening of the concrete support pipe 1 is closed by a plastic stopper 2. The hermetic stopper 2 is integrally molded by injection molding. The material of the stopper 2 is, for example, acrylonitrile-butadiene-styrene resin (ABS
Resin), acrylonitrile-styrene resin (AS resin),
Acrylonitrile-Acrylic-Styrene resin (AAS
Resin), polystyrene resin (PS resin), polycarbonate resin (PC resin) and the like. The sealing plug 2 is formed on a cylindrical fitting portion 6 that is tightly fitted into the end opening of the support tube 1, a closing bottom portion 7 that closes the outside of the cylindrical fitting portion 6, and an outer end portion of the fitting portion 6. It is composed of a flange portion 8.

The fitting portion 6 is tightly fitted into the support tube 1 and is bonded with an adhesive (for example, a resin-based solvent-based adhesive (Bond VP2000, manufactured by Konishi Co., Ltd.).
A large number of shallow grooves 9 extending in the longitudinal direction of the support tube 1 are formed. The groove 9 allows the adhesive to remain sufficiently on the outer peripheral surface of the fitting portion 6 when the fitting portion 6 is fitted into the supporting tube 1 so that the outer peripheral surface of the fitting portion 6 and the inner peripheral surface of the supporting tube 1 are separated from each other. It is for firmly adhering. That is, when the fitting portion 6 having an outer diameter substantially equal to the inner diameter of the support tube 1 is applied to the outer peripheral surface and fitted into the support tube 1, the adhesive on the outer peripheral surface is scratched by the inner peripheral edge of the support tube 1. Although the adhesive action is weakened by removing the groove 9, if the groove 9 is provided on the outer peripheral surface of the fitting portion 6 as described above, the adhesive remains sufficiently on the outer peripheral surface,
The fitting portion 6 is firmly adhered to the support tube 1 with an adhesive.

The outer shape of the flange portion 8 is the same as the outer shape of the support tube 1 so as to avoid unnecessary unevenness at the tube end portion.

On the outer end surface of the hermetic plug 2, that is, the outer end surface of the closed bottom portion 7, there is formed a recess 10 recessed toward the support tube 1. This recess 10 serves for temporarily placing the support tube 1 vertically at the construction site. That is, when the support tube 1 is suspended in air, the concave portion 10 at the lower end of the support tube 1 is hooked on the head of the nail hit on the formwork at the site, so that the support tube 1 is supported vertically and temporarily suspended. Can be placed. However, if the recess 10 is too deep or the angle of the outer peripheral surface 11 of the recess 10 is too tight, concrete enters the recess 10 and solidifies, so that it no longer serves its purpose. Therefore, the depth of the recess 10 is 3
The outer peripheral surface 11 of the recess 10 is tapered so that the outer peripheral surface 11 and the outer end surface of the sealing plug 2 (the outer end surface of the closed bottom portion 7 or the flange portion 8) are formed. It is preferred that the angle α is between 20 and 70 °, especially about 45 °. Thereby, even if the concrete enters the recess 10 and solidifies, it can be easily peeled and removed.

Concrete formwork support pipe 1 according to the embodiment of the present invention
Since its end opening is closed by the plastic sealing plug 2, concrete and water do not enter the inside of the pipe at the construction site. Therefore, it is possible to prevent the weight of the support pipe 1 from increasing due to intrusion of concrete or water, and the handling operation of the support pipe 1 is easy. Further, since the stopper 2 has a role of protecting the end of the supporting tube, the end of the supporting tube is not damaged or cracked.

Further, the fitting portion 6 of the tight plug 2 is provided on the outer peripheral surface of the support tube 1
Since it has a large number of shallow grooves 9 extending in the longitudinal direction, the outer peripheral surface of the fitting portion 6 and the inner peripheral surface of the support tube 1 are firmly bonded with an adhesive.

Further, a concave portion recessed toward the support tube 1 is formed on the outer end surface of the sealing plug 2.
Since 10 is formed, the temporary placement work of the support pipe 1 can be easily performed at the construction site. Furthermore, the outer peripheral surface of the recess 10
Since the angle between 11 and the outer end surface of the stopper 2 is 20 to 70 ° C,
Concrete does not adhere to the recess 10.

Further, since the fitting portion 6 of the hermetic plug 2 is formed in a tubular shape and the outer end portion thereof is closed by the closed bottom portion 7, the hermetic plug 2 itself is lightweight.

The concrete formwork support pipe according to the embodiment of the present invention has been described above, but the present invention is not limited to the above embodiment. For example, the support tube 1 may have another laminated structure, and the cross-sectional shape may be not only square but also other shape (for example, circular, that is, round pipe). Further, the fitting portion 6 of the hermetic plug 2 can be formed not only in a cylindrical shape but also in a prismatic shape (a cylindrical shape in the case of a round pipe) having a closed inside. In this case, the closed bottom portion 7 becomes a part of the fitting portion 6.

Further, in order to facilitate the fitting of the fitting portion 6 into the support tube 1, the tip portion of the fitting portion 6 may be tapered or the tip edge portion of the fitting 6 may be chamfered. Furthermore,
The outer shape of the flange portion 8 does not necessarily have to be the same as the outer shape of the support tube 1, and may be smaller or larger than the outer shape of the support tube 1. Further, the length and the thickness of the support tube 1 may be made smaller. The stopper 2 can be colored with the color shown.

Further, in the above-mentioned embodiment, the sealing plug is adhered to the main body of the frame support tube by using an adhesive, but the both may be adhered by using other adhering means.

[Effect of device]

As described above in detail, the concrete support pipe for construction or civil engineering work according to the present invention has the end opening closed by the tight plug, so that concrete or water does not enter the inside of the support pipe at the construction site. There is an advantage that the end of the support tube is not damaged or cracked. Furthermore,
Due to the concave portion formed on the outer end surface of the hermetic plug, the temporary placement work of the support pipe can be easily performed at the construction site. Furthermore, since the outer peripheral surface of the concave portion is tapered, concrete is unlikely to adhere to the concave portion, and even if concrete adheres, the concrete can be easily removed.

Further, since the fitting portion of the hermetic plug is formed in a tubular shape and the outer end portion thereof is closed by the closed bottom portion, there is an advantage that the hermetic plug itself is lightweight.

Further, the angle between the outer peripheral surface of the recess and the outer end surface of the stopper is 20 to 70.
When the angle is °, it is easier to remove the concrete solidified in the recess.

Further, by forming a large number of shallow grooves on the outer peripheral surface of the fitting portion of the hermetic plug, there is an advantage that the hermetic plug is firmly adhered to the support tube with an adhesive.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of the end of a concrete formwork support pipe for construction or civil engineering, and a stopper plugged into the opening of this support pipe end. FIG. 2 is a perspective view of the stopper shown in FIG. is there. 1 ... Concrete formwork support tubes for construction or civil engineering, 2
...... Seal stopper, 3 ... Middle layer, 4 ... Inner layer, 5 ... Outer layer, 6
... Fitting part, 7 ... Closed bottom part, 8 ... Flange part,
9 ... Groove, 10 ... Recess, 11 ... Outer peripheral surface of recess

Claims (4)

[Scope of utility model registration request] 1. In a concrete formwork support pipe made of fiber reinforced plastic for construction or civil engineering, the end opening of the support pipe is closed by a plastic stopper, and the stopper is tightly fitted into the end of the supporting pipe. It has a fitting part to be bonded and a flange part integrally formed on the outer end part of this fitting part, and a concave part recessed toward the support pipe is formed at the outer end part of the hermetic plug, and the outer peripheral surface of this concave part is formed. Concrete formwork support pipe for construction or civil engineering, characterized by a taper. 2. A fitting portion of a hermetic plug is formed in a tubular shape, an outer end portion thereof is closed by a closing bottom portion, and a concave portion is formed on an outer end surface of the closing end portion.
A concrete formwork support tube for construction or civil engineering according to claim 1. 3. The angle between the outer peripheral surface of the recess and the outer end surface of the stopper is
The concrete formwork support pipe for construction or civil engineering according to claim 1 or 2, characterized in that the angle is 20 to 70 °. 4. The concrete formwork support pipe for construction or civil engineering according to claim 1, wherein the fitting portion of the hermetic stopper has a large number of shallow grooves extending in the longitudinal direction of the support pipe on its outer peripheral surface.