JPH0710247U - Joint joint sheath for PC precast member - Google Patents

Abstract

(57) [Summary] [Object] To provide a joint sheath in the joint 3 of the PC precast members 1 and 2 which does not cause cement paste leakage into the sheath when the joint concrete or mortar is cast. [Structure] A rubber cylinder 7 having both ends fixed to a coil spring 6 is placed on the coil spring 6, and a retractable joint sheath in which guide pipes 4 and 5 are inserted inside the coil spring 6,
After being contracted in the longitudinal direction and suspended in the joint 3, the PC steel material is inserted, it is extended to connect the sheaths of the members 1 and 2 and insulate the joint.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a joint joint sheath used in a joint of a PC precast member joint such as a joint between a PC precast column and a beam.

[0002]

[Prior art]

 In the case of assembling PC precast members, especially in the case of buildings, the joints such as columns and beams, beam-to-beam joints, etc. are joined at the site by providing cast concrete or mortar construction joints with a width of about 20-40 mm. Most of the time. Such joints are joined together by introducing prestress by means of PC steel material in the joints. In this case, since the joint width is very narrow, 20 to 40 mm, it is very difficult to carry out the construction so as to completely prevent the cement paste from leaking into the sheath when the joint concrete is poured. As a result, there was a problem that the grout work in the sheath of the PC steel material for connecting the joint portion was incomplete.

On the other hand, conventionally, for example, the joint width is widened to about 100 to 150 mm, a PC precast member is attached, and then a joint sheath or the like is inserted from outside the joint, and taping is performed on the joint hoop. Also, there is a technology to attach a formwork and place concrete in joints. In this case, the joint width becomes large, which makes it unsuitable for the method of installing brackets on columns and placing beams, etc., and the construction cost of joints will increase because the amount of joint concrete will increase. is there.

As another means, after the PC precast member is erected by setting the joint width so that it can be taped from the outside (about 50 mm), the split sheath is covered with the sheath protruding from the PC precast member, and taping is performed. There is also a construction method to prevent the cement paste of joint concrete from leaking into the sheath. There is also a technique of taping by inserting a sheath having a small diameter into both sheaths instead of the split sheath. In these cases, taping is very time-consuming and the taping is likely to be incomplete, so cement paste may enter the sheath during joint concrete pouring, making it impossible to grout PC steel after tensioning.

Japanese Patent Publication No. 18228/1989 describes these improving techniques. In this technique, an elastic cylinder is axially compressed and inserted into the end of the PC steel material insertion hole of one of the PC precast members, and this is prevented with a stopper, and this stopper is used during construction. The elastic cylinder is detached and stretched so that it can be fitted into the cylinder fitting portion of the other precast member. Although this technique is an excellent technique, its operation may be restricted because the elastic cylinder may not operate smoothly.

[0006]

[Problems to be solved by the device]

 In view of the above circumstances, the present invention has an object to provide a joint joint sheath of a PC precast member which does not require taping and can be easily mounted in a joint and has a high sealing property. .

[0007]

[Means for Solving the Problems]

 The present invention was developed in order to achieve the above-mentioned object, and is a double guide pipe which is loosely fitted to each other and has a flange formed at one end thereof, and the double guide pipe is fitted onto the double guide pipe. A joint joint sheath for a PC precast member, characterized in that it is composed of a coil spring whose both ends are seated on each flange, and an expandable cylinder that is fitted onto this coil spring and fixed at both ends to both ends of the coil spring. is there.

[0008]

[Action]

 The joint joint sheath of the PC precast member of the present invention is inserted into the joint portion of the PC precast member through the joint gap, the PC steel material is inserted through this joint sheath, and then expanded inside the joint portion to form a closed sheath space. To do. Since this joint sheath does not have to be attached to the PC precast member in advance, it does not require troublesome work when manufacturing the PC precast member.

In addition, even if the joint facing surfaces are not parallel to each other, this joint sheath can bend the entire joint sheath with the left and right guide pipes separated from each other, so that the end surfaces of the sheath adhere to both facing concrete surfaces. The sheath seal is complete. In addition, this joint sheath can be manufactured to fit any joint size. Furthermore, even if the joint size on site differs from the design, it is sufficient to select and insert a joint sheath with a length that is compatible with it.

This joint sheath is inserted into the joint in a contracted state, and used by being extended at an arbitrary position. As the expandable cylinder, for example, a rubber cylinder processed so that both ends are locked to both ends of the coil spring can be used. If the length of this rubber cylinder is slightly shorter than the joint width, this cylinder can be used. It can be formed into a predetermined shape without applying an extra stretching force to it. Since the rubber cylinder is backed up by the guide pipe and coil spring, it does not require so much strength for joint concrete pouring. The rubber cylinder is fixed at both ends in the longitudinal direction to both ends of the coil spring, and the middle part is free, so that it can be easily expanded and contracted into a free shape.

[0011]

【Example】

 A joint sheath according to an embodiment of the present invention is shown in FIGS. FIG. 1 is a sectional view showing a state in which the precast member is mounted in a joint, FIG. 2 is a sectional view showing a state immediately before mounting, FIG. 3 is an exploded view, and FIG. 4 is a perspective view showing a reduced state. The joint sheath of the present invention, as shown in an exploded view in FIG. 3, has a coil spring 6 and an elastic rubber cylinder 7 which is fitted on the coil spring 6 and has both ends fixed to both ends of the coil spring 6. The guide pipes 4 and 5 are inserted.

The rubber cylinder 7 is provided at both ends thereof with fixed end portions 11 covering both ends of the coil spring 6, and the fixed end portions 11 are fitted to both end portions of the coil spring 6, respectively. The middle portion of the rubber cylinder 7 is not fixed to the coil spring at all. The rubber cylinder 7 is set so that its free length is slightly shorter than the joint width to which this joint sheath is applied. The coil spring 6 has a free length longer than the joint width to be applied, and when the coil spring 6 is mounted in the joint in the state shown in FIG. 1, the length and the spring constant are determined so that the coil spring 6 has a sufficient urging force in the extending direction. The guide pipes 4 and 5 are loosely fitted to each other to form a double guide pipe with a flange formed at one end thereof. The double guide pipes are inserted into each other with the flanges at both ends to be integrated. To do. The flanges 12 and 13 are seats on which the coil spring 6 is seated. A ring-shaped sealing material 8 is attached to the outer surface of this flange. If the lengths of the guide pipes 4 and 5 are shorter than 1/2 of the joint width, even when the opposing concrete surfaces in the joint are not parallel when mounted in the joint in the state shown in FIG. It is preferable because the flange adheres closely to the concrete surface.

When the guide pipes 4 and 5 are inserted into the coil spring 6 covered with the rubber cylinder 7 from both sides, the coil spring 6 is pushed and contracted, and the guide pipes are fitted and fixed to each other, the state becomes usable. At this time, the rubber cylinder shrinks in a bellows shape along with the spring. FIG. 4 is a perspective view showing the assembled state in this state, and shows a state in which the length of the joint sheath of the embodiment is reduced and both the flanges 12 and 13 are drawn together and fitted into the jig 21. . The jig 21 is composed of a horseshoe-shaped holding plate 22, which is in contact with approximately half of the outer surfaces of the flanges 12 and 13, a connecting member 23 that connects the holding plate 22, and a hanging member 24. The connecting member 23 may be a member whose length can be adjusted.

The joint sheath assembled as shown in FIG. 4 is suspended in the joint 3 of the PC precast members 1 and 2 as shown in FIG. 2, and the PC steel material 10 is inserted therethrough. Then, when the jig 21 is pulled up, the joint sheath is externally fitted to the PC steel material 10 and extends between the opposing end faces of the PC precast members 1 and 2 as shown in FIG. Form a closed sheath space.

The coil spring 6 presses the flanges 12 and 13 onto the concrete via the sealing material 8. The inner surface of the rubber cylinder 7 is backed up by the coil spring 6 to form a closed cylinder. In the joint sheath of the embodiment, even if the opposing concrete end faces in the joint 3 are not parallel to each other, the flanges 12 and 13 are brought into close contact with each other in conformity with the concrete face, and the sealing is performed via the seal material 8 so that the joint sheath is sealed. Is complete and there is no risk of cement paste leaking into the sheath when the joint concrete is cast.Because it is possible to select a joint sheath with an appropriate longitudinal dimension according to the joint dimensions, it is rational. Is.

[0016]

[Effect of device]

 According to the present invention, the joint sheath can be completely insulated from the joint, and the cement paste does not leak into the sheath when the joint concrete is placed. Therefore, the intra-sheath grouting can be completely performed. In addition, it is easy to install and install in an appropriate position without requiring any taping, and even if the actual joint size is different from the design, the work can be performed in conformity with this and it is possible to complete the joint construction. There are many places to donate.

[Brief description of drawings]

FIG. 1 is a sectional view of a joint showing a joint state of a joint joint sheath of the present invention.

FIG. 2 is a sectional view of a joint showing a method of attaching a joint joint sheath of the present invention.

FIG. 3 is an exploded view of a joint joint sheath of the present invention.

FIG. 4 is a perspective view of a joint joint sheath of the present invention.

[Explanation of symbols]

1, 2 Precast member 3 Joint 4, 5 Guide pipe 6 Coil spring 7 Rubber cylinder 8 Sealing material 10 PC steel material 11 End part 12, 13 Flange 21 Jig 22 Holding plate 23 Connecting material 24 Hanging material

Claims (1)

[Scope of utility model registration request] 1. A double guide pipe which is loosely fitted to each other and has a flange formed on one end thereof, a coil spring which is fitted on the double guide pipe and has both ends seated on the respective flanges, and the coil. A joint joint sheath for a PC precast member, characterized in that the joint pre-cast member comprises an expandable and contractible cylinder that is fitted onto a spring and has both ends fixed to both ends of the coil spring.