JP2651501B2 - Pipe sheath for PC steel - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a PC steel pipe sheath through which a PC steel material such as a PC steel material is inserted.

[Prior Art] Generally, as the size of a steel structure increases, not only does a column, a beam, and the like undergo large bending, but also the construction cost for providing a strength sufficient to withstand the bending in design is increased. In view of the above-mentioned problems, the present applicant has taken the above problems into consideration, and has made a truss-like structure with chords and lattice beams, and at least distributes a PC steel material integrally along the chords. Previously proposed truss-type steel structures, such as those provided, were pre-stressed by PC steels arranged along the length of the beam, and the stress generated when the beam was stretched. Is canceled by the prestress, and the apparent force applied to the beam is reduced.

In addition, the PC steel material is usually inserted through a pipe sheath continuously arranged along the length direction of the beam, and is tensioned by jacks provided at both ends of the pipe sheath so as to generate tension. It has become.

"Problems to be Solved by the Invention" By the way, when a PC steel material is provided in the pipe sheath,
The jacks placed at the ends apply uniform prestress to the entire beam, but the prestress to be applied to the beam varies in size depending on its position, and may be partially excessive or insufficient. was there.

"Means for Solving the Problems" The present invention has been made in view of the above circumstances, and has as its object to obtain a pipe sheath for PC steel that can partially adjust the prestress. In order to achieve this, the beam is fixed at intervals along the length of the
A plurality of fixed sheath tubes each having an inner hole through which a steel material is inserted, an intermediate sheath tube detachably provided between the fixed sheath tubes, and having an inner hole through which a PC steel material is inserted; and the fixed sheath tube. A joint tube is provided which is screwed into a thread groove formed on the outer periphery of the end of the tube and the intermediate sheath tube and connects the two together.

"Example" Hereinafter, an example of the present invention will be described with reference to FIGS.

First, in FIGS. 1 and 2, reference numeral 1 denotes a beam such as an H-shaped steel used as a lower chord member of a truss. This beam is supported by a lattice material 2, and a plurality of fixed sheath tubes 3, 3, 3 are arranged along the longitudinal direction thereof along the same axis. These fixed sheaths 3, 3, 3 are formed with holes (internal holes) 4, 4, 4 through which a PC steel material (described later) is inserted, and screw grooves 5, 5 # are formed on the outer peripheral surfaces at both ends. A support portion 6 provided on the beam 1,
6, are respectively fixed by ‥.

Further, intermediate sheath tubes 10, 10 are attached between the fixed sheath tubes 3, 3, 3. The intermediate sheath tubes 10, 10 are formed with holes (internal holes) 11, 11 through which a PC steel material is inserted, similarly to the fixed sheath tubes 3, 3, 3, and screw grooves are formed on the outer peripheral surfaces at both ends. 12, 12, and 各 々 are respectively formed, and screw grooves 5, 5, and
Joint pipes 13 and 13 screwed to 5 are attached. On the inner peripheral surface of both ends of these joint pipes 13, 13,
A screw groove (not shown) is formed, and when this screw groove is screwed with the screw grooves 5, 5, 5 and the screw grooves 12, 12, 12, ‥, the fixed sheath tubes 3, 3, 3 Intermediate sheath tube 10,
10 is connected as shown in FIG.

Next, a method of attaching an intermediate sheath tube to the fixed sheath tube of the pipe sheath configured as described above, and a method of inserting a PC steel material through these sheath tubes will be described in the order of steps.

(1) Attach the joint pipes 13, 13, ‥ to each of the ends of the intermediate sheath pipes 10, 10 as shown in FIG.

(2) The guide wire 20 attached to the tip of the PC steel (not shown) is inserted through the intermediate sheath tubes 10, 10, 10, the joint tubes 13, 13, 13, and the fixed sheath tubes 3, 3, 3 in order. .

(3) The intermediate sheath tubes 10, 10 with the joint tubes 13, 13 attached thereto are fixed sheath tubes 3, 3, 3 as shown in FIG.
And the same axis.

(4) By rotating the joint pipes 13, 13, the screw portions 5 of the fixed sheath pipes 3, 3, 3 as shown in FIGS.
5. Screw in ‥.

(5) Pull the guide wire 20 inside each sheath tube.
Insert into PC steel 21.

(6) When a jack (not shown) is provided at an end of the fixed sheath tube 3, 3, 3 and the PC steel material 21 is tensioned,
In the above process, the fixed sheath tube 3 of the intermediate sheath tube 10
Although the case of attaching to the third and third tubes has been described, the case of removing the intermediate sheath tubes 10 and 10 may be performed in a procedure reverse to the above steps.

In the pipe sheath described above, the joint pipes 13, 1 and 10 are located between the fixed sheath pipes 3, 3, 3 and the intermediate sheath pipes 10, 10, 10.
3, the sheath tube is connected or divided by interposing ‥, so that the length of a continuous section can be easily adjusted. Thereby, the positions of the ends of the fixed sheath tubes 3, 3, 3 to which the jacks are attached can be arbitrarily determined in the longitudinal direction of the beam 1, and an optimum prestress is provided for any section of the beam 1. Can be given.

In the above-mentioned pipe sheath, the fixed sheaths 3, 3,.
By connecting the intermediate sheath 3 and the intermediate sheath 10, 10, the sheath tube can be arranged in the entire section of the beam 1 to be prestressed. Similarly, the PC steel can be totally protected.

[Effects of the Invention] As described in detail above, according to the present invention, a plurality of fixed sheath tubes fixed along a beam, an intermediate sheath tube disposed between these fixed sheath tubes, and the fixed sheath tube And the joint tube connecting the intermediate sheath tube, the length of the entire tube can be easily adjusted, whereby the end of the fixed sheath tube can be arranged at an arbitrary position of the beam. At the same time, it is possible to give an optimal prestress to any section of the beam by the jacks arranged at the ends.

[Brief description of the drawings]

1 to 5 are views showing a configuration of a pipe sheath shown as one embodiment of the present invention. FIG. 1 is a state diagram showing a state where an intermediate sheath tube is removed from a fixed sheath tube, and FIG.
The figure is a state diagram showing a state in which the intermediate sheath tube and the fixed sheath tube are connected, and FIGS. 3 to 5 are explanatory diagrams for explaining a process of connecting the intermediate sheath tube to the fixed sheath tube. 1 ... beam, 3 ... fixed sheath tube, 4 ... hole (internal hole),
10 ... middle sheath tube, 11 ... hole (internal hole), 12 ... screw groove, 13 ... joint tube, 21 ... PC steel material.

Claims (1)

(57) [Claims] 1. A pipe sheath for a PC steel material into which a PC steel material is inserted, wherein a plurality of fixed sheaths are fixed at intervals in the longitudinal direction of the beam and each have an internal hole through which the PC steel material is inserted. A tube, an intermediate sheath tube detachably provided between the fixed sheath tubes, and having an internal hole through which a PC steel material is inserted, and screws formed on outer circumferences of ends of the fixed sheath tube and the intermediate sheath tube, respectively. A pipe sheath for PC steel, comprising: a joint pipe screwed into the groove to connect the two to each other.