JPH0759804B2 - Mantle protection tube for cable-stayed bridge cable and erection method of mantle protection tube - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an outer jacket protection tube for covering cables of a cable-stayed bridge in order to prevent corrosion and the like, and more specifically, the outer jacket protection tube The present invention relates to a structure for connecting mantle protective pipes adjacent to each other, which is convenient when coating a cable over a bridge.

(Prior Art) Generally, a cable in a cable-stayed bridge is used by being exposed outdoors, and therefore it is necessary to prevent the cable made of a bundle of steel wires from being cut due to corrosion. For this reason, when the cable-stayed bridge cable is installed, the mantle protective pipes adjacent to each other are successively connected by an adhesive so as to be fixed, and the mantle protective pipes are pulled up by a lifting means such as a motor winch. Was installed.

That is, the outer jacket protection tube is a slender cylinder in appearance, and is formed by tapering the inner surface of the tip portion and processing the rear end portion into a shape that fits into the inner surface of the tip portion. is there. Therefore, an adhesive is applied to the rear end surface of the outer jacket protection tube, and an adhesive is applied to the inner surface of the taper portion at the tip of the outer jacket protection tube, and the rear end of the outer jacket protection tube is attached to the next jacket. It was fitted and adhered to the tip of the protective tube, and was left standing or heat-treated in a heating / drying box until the required strength was obtained, and it was fixed so as to obtain early strength. This was repeated and the above-mentioned mantle protection tube was installed.

(Problems to be solved by the invention) However, in the above-mentioned cable-stayed bridge mantle protection pipe construction method,
There is a problem that an adhesive is used to connect the mantle protective tubes adjacent to each other and it takes a long time to cure the adhesive, and it takes a special time to quickly dry and cure the adhesive used for the adhesion. The use of a heating / drying box has the drawback that it requires a lot of work and cost.

The present invention has been made in view of the above-mentioned problems, and an outer protective tube for a cable-stayed bridge cable and a method for constructing the protective tube, which has a structure in which the outer protective tube can be easily connected and can be surely connected and connected. The purpose is to provide.

(Means for Solving the Problems) The gist of the method for constructing the mantle protection pipe of a cable-stayed bridge cable according to the present invention is to stretch a wire rope for pulling the mantle protection pipe between the main tower and the main girder of the cable-stayed bridge. A slender synthetic resin cylinder, which has a tapered portion with a small diameter toward the end face on the one end side of the cylinder, and a flange portion is provided on the end face. And a plurality of slits along the longitudinal direction of the pipe, and at the other end of the side where the taper portion and the flange portion are provided, an inner taper portion that includes the taper portion and a groove that engages with the flange portion Prepare a required number of mantle protection tubes with a fitting part formed of and, while suspending the mantle protection tubes with the wire rope, apply an adhesive to at least one end side of the mantle protection tubes to protect the mantle. Development of adhesive strength of the adhesive by connecting the pipes successfully That is, the mantle protection pipes are sequentially connected without waiting, and are erected by the wire rope from the main girder side to the main tower side. Further, the gist of the jacket protection tube for a cable-stayed bridge cable according to the present invention is that it is a cylinder made of an elongated synthetic resin as a whole, and a jacket protection tube covered and erected on the cable is used for corrosion protection of the cable-stayed bridge cable. , Forming a taper portion having a small diameter toward the end surface on the one end side of the cylinder, providing a flange portion on the end surface, and providing a plurality of slits along the pipe longitudinal direction in the taper portion and the flange portion, On the other end of the side where the taper portion and the flange portion are provided, a fitting portion including an inner taper portion that includes the taper portion and a groove that engages with the flange portion is formed.

(Operation) As described above, according to the mantle protection tube of the cable-stayed bridge cable of the present invention, the taper portion and the flange portion, which are provided on one end side of the cylinder, are provided when the outer sheath protection tube is covered and installed on the cable. By using an adhesive together and connecting the outer tube adjacent to each other successfully, it is possible to rapidly construct.

Further, according to the method for constructing the mantle protective tube of the present invention, the adhesive is applied to one end of the mantle protective tube having the taper portion and the flange, and the mantle protective tubes are successively coated without waiting for the strength to develop. It can be connected successfully and pulled up to the main tower side with a wire rope, which is an efficient construction work.

Embodiment An embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a front view in which a part of the mantle protection tube 1 according to the present invention is cut away. 2 (a) and 2 (b) are a partially enlarged side view and a sectional view of the same.

The material of the mantle protective tube 1 is fiber-strength plastic (hereinafter referred to as FRP), and the outer appearance of the mantle protective tube 1 is an elongated cylinder having a total length of about 6 m, an outer diameter of about 140 mm, and a wall thickness of about 4.5. mm
It is of a degree.

Then, a tapered portion 3 having a small diameter (approximately taper 1/30) toward the end surface 2a of the one end side 2 is formed on one end side 2 of the cylinder, and a flange portion 4 is provided on the end surface 2a. The taper portion 3 and the flange portion 4 are provided with a plurality of slits 5 along the pipe longitudinal direction.

As shown in FIG. 2 (a), the slits 5 are evenly arranged on the outer circumference of the cylinder and provided at 12 places, but the number is not limited to this, and it may be 6 places, 8 places or 12 places or more. Of course, it is also good.

The engaging piece portion 5a formed by the slit 5 is elastically deformed in the radial direction of the pipe by a pressing force.

Further, as shown in FIG. 1 and FIG. 2B, an inner taper including the taper portion 3 on the other end side 6 of the one end side 2 provided with the taper portion 3 and the flange portion 4 of the cylinder. A fitting portion 9 including a portion 7 and a concave groove 8 that engages with the flange portion 4 is provided to form the outer protective tube 1.

In order to use the mantle protection tube 1 thus constructed, first, a erection scaffold for joining is constructed on the main girder 10, and a wire rope for erection is erected on the main girder 10 and the main tower 11, and Install a wire rope for pulling the mantle protection tube.

Then, an adhesive (two-component epoxy resin or the like) is applied to one end side 2 of the outer jacket protection tube 1. The adhesive is also applied to the inner taper portion 7 of the fitting portion 9 on the other end side 6 of the outer sheath protection tube 1 to be cut next to close the engagement piece portion 5a on the one end side 2 of the outer sheath protection tube 1. This is fitted to the other end side 6 of the outer jacket protection tube 1 at the next stage (see FIG. 2B).

Then, the engagement piece 5a is deformed inward in the radial direction of the tube while being inserted into the other end side 6 of the outer jacket protection tube 1, and is further pushed in so that the flange portion 4 is recessed in the other end side 6. When it reaches 8, it elastically expands and returns to engage with the recessed groove 8, and by repeating this, the outer jacket protection tube 1 is successively connected, and this is suspended from the erection wire rope by a hanger or the like. Then, the wire rope for pulling up is sequentially pulled up to the main tower 11.

Next, when the erection of the mantle protection tube 1 is completed, a PC copper wire is inserted into the erected mantle protection tube 1 and sent by a feeding means such as a pushing machine, and the PC steel wire is supplied to the main tower 11 and the main girder 10. And erection with tension.

In this way, the mantle protection tube 1 is erected, but in the connection structure according to the present invention, the engagement between the engagement piece portion 5a and the concave groove 8 has a strength of about 350 kg to 400 kg as a result of a tensile test. It was found that it is possible to install only this mechanism during installation without using an adhesive, and it has sufficient strength as a jacket protection tube for cable-stayed bridge cables. As described above, in the work of connecting the mantle protection tube according to the present invention, the adhesive is not necessary for the connection, but to prevent the leakage of the grout material filled after inserting the PC steel wire into the mantle protection tube. , Slit 5
In order to form an alkali-proof film of glass fiber exposed when the is provided, for reinforcing the bonding strength, etc.,
It is sufficient that the mantle protective tube is installed and then slowly cured to develop strength. Therefore, it is not necessary to use a heating / drying box when connecting the mantle protection tube successfully.

As another embodiment of the present invention, as shown in FIG. 4 to FIG.
A flange portion 13 and a slit 14 are provided to form a mantle protection tube 15, and the end portion of the mantle protection tube 15 is fitted separately from this.
A coupler (19) having a fitting portion (18) formed of an inner taper portion (16) and a concave groove (17) engaging with the flange portion (13) is provided on the inner surface of the cylinder. Then, by fitting the end portion of the outer jacket protection tube 15 with this coupler 19, the outer jacket protection tube 15 is sequentially connected in succession and is installed in the same manner as described above.

Although one embodiment of the jacket protection tube for the cable-stayed bridge cable according to the present invention has been described, it goes without saying that various design changes can be made without changing the gist of the present invention.

(Effects of the Invention) As described above, the method for constructing the jacket protection tube for a cable-stayed bridge cable according to the present invention facilitates the successful connection of the jacket protection tube, saves labor, and provides sufficient connection strength. Since it can be obtained, the protection of the adhesive applied to one end of the mantle protective tube in order to prevent the water leakage of the grout material and to form the alkali-proof film of the glass fiber does not have to wait for the strength of the adhesive to develop. The pipes can be successfully connected, and the work process of leaving strength of the adhesive for connection or heat treatment as in the conventional case to develop strength is not necessary in the erection method according to the present invention, so that the construction period is greatly reduced. Can be shortened,
It has an excellent effect of reducing the construction cost. In addition, since the outer sheath protection tube of the cable-stayed bridge cable according to the present invention does not require an adhesive for connection, it can be erected and connected by only the outer sheath protection tube, and the length of the main tower and the main girder can be increased. It will be able to withstand its own weight after being installed diagonally in the section,
There is an excellent effect that the work of constructing the mantle protection tube can be quickly constructed and the work efficiency is improved.

[Brief description of drawings]

FIG. 1 is a front view in which a part of a mantle protection tube according to the present invention is cut away, and FIGS. 2 (a) and 2 (b) are also partially enlarged side views, sectional views, and FIG. An explanatory view showing a state in which the mantle protection tube is used, and FIGS. 4 to 5 are explanatory views showing a used state according to another embodiment of the present invention and a front view in which a part thereof is also broken. 1 ... Mantle protection tube, 2 ... One end side, 2a ... End surface, 3, 12 ...
… Taper part, 4,13 …… Flange part, 5,14 …… Slit,
5a ...... engagement piece part, 6 ... other end side of mantle protection tube, 7 ... inner taper part, 8 ... recessed groove, 9 ... fitting part, 10 ... main girder, 11
…… Main tower, 19 …… Coupler.

Claims (2)

[Claims] 1. A wire rope for pulling a mantle protection tube is stretched between a main tower and a main girder of a cable-stayed bridge, and is an elongated synthetic resin cylinder, which is provided on one end side of the cylinder. A tapered portion having a small diameter is formed toward the end portion, and a flange portion is provided on the end surface of the tapered portion, and a plurality of slits along the pipe longitudinal direction are provided in the tapered portion and the flange portion, and the tapered portion and the flange portion are provided. On the other end side of the wire side, a required number of mantle protective tubes each having a fitting portion formed of an inner tapered portion including the tapered portion and a concave groove engaging with the flange portion are prepared, and the wire rope An adhesive is applied to at least the one end side of the mantle protection pipe while suspending the mantle protection pipe, and the mantle protection pipes are successfully connected, and the mantle protection pipes are sequentially connected without waiting for the adhesive strength of the adhesive to develop. Connect the wire rope from the main girder side to the main tower side Cable-stayed bridge erection method mantle protecting tube of the cable, characterized in that the erection. 2. An outer cover protection tube which is a slender cylinder made of synthetic resin and is covered and erected on a cable for cable-stayed bridge cables so as to have a smaller diameter toward the end surface on one end side of the cylinder. And a flange portion is provided on the end surface, a plurality of slits are provided in the taper portion and the flange portion along the longitudinal direction of the pipe, and the taper portion and the flange portion are provided on the other side. An outer jacket protection tube for a cable-stayed bridge cable, characterized in that a fitting portion composed of an inner taper portion including the taper portion and a concave groove engaging with the flange portion is formed on an end side.