JP6927489B2 - Wiring method for PC steel - Google Patents

Description

The present invention relates to a technique for wiring a long PC steel material for introducing a tension force when constructing a prestressed concrete structure by a post-tension method, and particularly has poor flexibility even in a narrow construction site ( It relates to a technique for preferably wiring a coated PC steel stranded wire having a large diameter (which is difficult to bend and has poor workability).

At present, in prestressed concrete girders using the post-tension method for bridges, a cable assembly in which a plurality of PC steel stranded wires are bundled, which is an example of PC steel, is frequently used as an inner cable. The post-tension method is a method of introducing prestressed concrete by tensioning the PC steel stranded wire inserted into the sheath portion of the concrete member after the concrete strength is developed. The inner cable is a cable that introduces prestress by transmitting the tension force of the PC steel stranded wire by adhering to concrete.

In prestressed concrete members using the general post-tension method, a polyethylene (resin) or metal sheath is placed before the concrete is placed, and the aggregate cable is placed in this sheath after the concrete is placed. After inserting and the strength of the concrete reaches the specified strength, the aggregated cable is tensioned and fixed, and finally, cement milk is used for the purpose of rust prevention treatment of the aggregated cable and adhesion and integration treatment of the aggregated cable and concrete. Etc. (a resin compound sometimes called grout) is injected between the assembly cable and the sheath.

In such a general post-tension method, a feeding device for inserting a PC steel stranded wire into a sheath arranged on a bridge or the like from the inner circumference of a reelless coil is described in, for example, Japanese Patent Application Laid-Open No. 6-219641 (Patent Document). It is disclosed in 1). This feeding device is a PC steel stranded wire feeding device that sandwiches a PC steel stranded wire with a catching tool that rotates in opposition and sends it out, and in a cradle that can rotate this catching tool around the PC steel stranded wire as an axis. It is characterized by being placed in. According to this PC steel stranded wire feeding device, since the catcher is in a cradle that can rotate around the PC steel stranded wire, twisting by rotating the catcher in the untwisting direction is not accumulated. .. Therefore, it is not necessary to loosen the tightening force so that the PC steel stranded wire can rotate between the traps, and even when the feeding resistance is high, the PC steel stranded wire can be reliably fed out.

Japanese Unexamined Patent Publication No. 6-219641

According to the feeding device disclosed in Patent Document 1, when the PC steel stranded wire is unwound from the inside of the reelless coil, the feeding resistance is high because it is rotated in the direction of untwisting one rotation generated for each one-turn feeding. Even in this case, it is possible to ensure that the PC steel stranded wire is sent out.
By the way, in a construction site such as a bridge, since the construction space is narrow, it is often impossible to install a PC steel stranded wire on an extension line in the opening direction of the sheath. For example, if the construction space is only in the direction opposite to the opening direction of the sheath, the PC steel stranded wire is bent by the operator's manual force (here, it is bent in a U shape so as to change the direction by 180 degrees). The changed direction PC steel stranded wire must be inserted into the sheath. If the diameter of the PC steel stranded wire is large, or if the outer layer of the PC steel stranded wire is coated with a resin such as epoxy, the flexibility of the PC steel material becomes very poor, and only human power is required without using a jig. At present, it is difficult to bend the PC steel material and insert it into the sheath. Such a problem cannot be solved by adopting the feeding device disclosed in Patent Document 1.

The present invention has been developed in view of such problems, and an object of the present invention is to preferably use a PC steel material having poor flexibility when constructing a prestressed concrete structure by a post-tension method. It is to provide a wiring method of a PC steel material which can be wired to a sheath.

In order to achieve the above object, the wiring method of the PC steel material according to the present invention takes the following technical means.
That is, the method of wiring the PC steel material according to the present invention is a method of wiring a long PC steel material for introducing a tension force when constructing a prestressed concrete structure by a post-tension method, and is a method of wiring the long PC steel material to the PC steel material. In a state where the PC steel material is aligned with at least a part of the outer diameter of the disk-shaped member having a corresponding curvature, the PC steel material is advanced in the long longitudinal direction to form the shape of the outer diameter. By bending the PC steel material so as to correspond to the bending step and advancing the PC steel material in the longitudinal direction, the PC is separated from the disk-shaped member from the state along the disk-shaped member. Includes an insertion step of inserting the steel material into a hollow sheath placed in a concrete structure.

Preferably, in the bending step, the PC steel material is aligned with at least 1/6 of the outer diameter peripheral length of the disk-shaped member, and the direction in which the PC steel material is started to be aligned with the disk-shaped member and the circle. It can be configured so that the direction in which the PC steel material begins to separate from the plate-shaped member is changed by 60 degrees or more.
More preferably, the disk-shaped member is a main sheave, and the bending step can be configured to bend the PC steel material by sandwiching the PC steel material with a guide roller on the outer diameter of the main sheave. ..

More preferably, before the bending step, the PC steel material is brought into contact with the outer diameter of the main sheave, sandwiched between the guide rollers, and the guide rollers are separated along the outer diameter of the main sheave. By moving the PC steel material, it can be configured to further include a preparatory step for setting the PC steel material on the main sheave.
More preferably, before the bending step, the PC steel material is fixed to the outer diameter of the main sheave and the PC steel material is sandwiched between the guide rollers to rotate the main sheave. Can be configured to further include a preparatory step to set the main sheave.

More preferably, in the bending step, the PC steel material can be configured to advance in the long longitudinal direction by using mechanical power other than human power.
More preferably, in the bending step, at least one of a method of extruding the PC steel material in the long longitudinal direction using the mechanical power and a method of rotating the disk-shaped member using the mechanical power. According to the above method, the PC steel material can be configured to advance in the longitudinal direction of the long length.

More preferably, it is configured to further include a straightening step between the bending step and the insertion step to correct the bending habit that is attached to the PC steel material in the bending step and remains after the bending step. be able to.
More preferably, the bending step can be configured to bend the PC steel using a disc-shaped member having a curvature equal to or greater than the maximum allowable curvature set for the PC steel.

More preferably, the PC steel material, a line of epoxy resin coating PC strand, wherein the bending step, the disc-shaped member having a 32 times or more the radius of the diameter of the line from the previous SL epoxy resin coating PC strand It can be configured to bend the PC steel material by using it.

According to the wiring method of the PC steel material according to the present invention, when the prestressed concrete structure is constructed by the post-tension method, the PC steel material having poor flexibility can be preferably wired to the sheath.

It is a figure for demonstrating the wiring apparatus of PC steel material for realizing the wiring method of PC steel material which concerns on embodiment of this invention. It is a figure for demonstrating the advancing method of advancing a PC steel material in the wiring method of a PC steel material shown in FIG. It is a figure for demonstrating the 1st setting method of setting a PC steel material in the wiring method of a PC steel material shown in FIG. It is a figure for demonstrating the 2nd setting method of setting a PC steel material in the wiring method of a PC steel material shown in FIG. It is a figure for demonstrating the straightening method which corrects the bending habit attached to the PC steel material before inserting a sheath in the wiring method of the PC steel material shown in FIG. In the wiring method of the PC steel material shown in FIG. 1, it is a figure for demonstrating the outer diameter circumference length of the main sheave along which the PC steel material runs, and the angle at which the PC steel material is changed in direction. It is a figure for demonstrating the wiring method of the conventional PC steel material which is compared with the wiring method of the PC steel material shown in FIG. It is a figure for demonstrating a more specific wiring apparatus of PC steel material for realizing the wiring method of PC steel material shown in FIG. It is a detailed plan view (A) and side view (B) of the wiring device of the PC steel material shown in FIG.

Hereinafter, the wiring method of the PC steel material according to the embodiment of the present invention will be described together with the wiring device for realizing this wiring method based on the drawings. In the following, although not limited to, the PC steel material is a PC steel stranded wire, and in particular, from an epoxy resin-coated PC steel having high durability called ECF strand (Epoxy Coated and Field Strand). Described as a line. This ECF strand is preferable in that the outer layer of the PC steel stranded wire can be completely coated with a high-quality epoxy resin to dramatically improve the corrosion resistance of the PC steel stranded wire, but the outer layer is coated with an epoxy resin. As a result, the flexibility becomes very poor, and in particular, it is extremely difficult to bend the ECF strand having a large diameter by human power alone and insert it into the sheath without using a jig (tool, device).
[Wiring device and wiring method]
The wiring device for the PC steel material for realizing the wiring method for the PC steel material according to the present embodiment will be described with reference to FIG. 1, and the wiring method for the PC steel material according to the present embodiment will be described. The PC steel material 200 includes various PC steel stranded wires or various coated PC steel stranded wires. 1 (A) shows the overall configuration of the wiring device for realizing the wiring method according to the present embodiment, and FIG. 1 (B) shows an enlarged view of the wiring device 100 in FIG. 1 (A). A side view of the wiring device 100 in FIG. 1 (B) is shown as (C), and an enlarged view of the region D portion shown in FIG. 1 (C) is shown as FIG. 1 (D). In addition, in FIG. 1C and FIG. 1D, the PC steel material 200 (only) is shown in a cross-sectional view.

As shown in FIG. 1, the wiring device 100 is installed on the gantry 510 of the scaffolding 500 provided in the existing structure 400, and the PC steel material is used for at least a part of the outer diameter peripheral length of the main sheave 110 of the wiring device 100. It is a wiring device 100 that changes the traveling direction of the PC steel material 200 from the arrow X direction to the arrow Y direction by 180 degrees along the line 200 and inserts it into the hollow sheath 310 embedded in the concrete structure 300. In the present invention, the length of the PC steel material 200 along the outer diameter peripheral length of the main sheave 110 (ratio to the total outer diameter peripheral length) and the direction of the PC steel material 200 are changed from the arrow X direction to the arrow Y direction. All of the angles to be set are approximate values, but "abbreviation", "about", etc. may not be described.

Since the existing structure 400 is present as described above, the construction space is narrow, and the PC steel material 200 cannot be inserted into the sheath 310 from the extension line in the opening direction of the sheath 310. Therefore, by the wiring device 100 and the wiring method according to the present embodiment using the wiring device 100, the traveling direction of the PC steel material 200 is changed by 180 degrees from the arrow X direction to the arrow Y direction, and concrete. It needs to be inserted into the hollow sheath 310 embedded in the structure 300.

The wiring device 100 includes a main sheave 110 which is a disk-shaped member having a curvature (often defined by a radius of curvature) corresponding to the PC steel material 200 to be constructed, and a PC steel material 200 having an outer diameter of the main sheave 110. It may be described as a pull-out side guide roller 120 for holding the guide roller 120) and an insertion-side guide roller 130. The PC steel material 200 has an outer diameter of the main sheave 110, such as a drawer side guide roller 120 and an insertion side guide roller 130 (these two may be simply referred to as a guide roller, a guide roller 120, and a guide roller 130). It is necessary to provide at least one guide roller for sandwiching the.

The main sheave 110 is supported by a rotating shaft 112 so as to be rotatable in the arrow R (1) direction, and the drawer side guide roller 120 is supported by a rotating shaft (not shown) so as to be rotatable in the arrow R (2) direction. ), And the insertion side guide roller 130 is supported by a rotation shaft (not shown) so as to be rotatable in the direction of arrow R (3). In this wiring device 100, the rotation axes of the drawer side guide roller 120, the insertion side guide roller 130, and the main sheave 110 are horizontal axes (axis extending in the horizontal direction), but the present invention rotates in this way. The direction of the axis is not limited to the horizontal direction.

As shown in FIGS. 1C and 1D, the main sheave 110 includes a groove 114 along the cross-sectional shape of the PC steel material 200 and a rib 122 for preventing detachment, and the guide roller 120 is the same as the main sheave 110. Is provided with a groove 124 along the cross-sectional shape of the PC steel material 200 and a rib 122 for preventing detachment. The guide roller 130 also has a groove along the cross-sectional shape of the PC steel material 200 and a rib for preventing detachment, like the main sheave 110 and the guide roller 120. The main sheave 110 and the guide rollers 120, 130 are the surface layer of the PC steel material 200 (the material of this surface layer is a resin such as epoxy when the surface layer of the PC steel material is coated, and the surface layer of the PC steel material. Is a PC steel material when it is not coated), and a resin such as epoxy coated on the surface layer of the PC steel material 200 and a material such as industrial plastic that does not damage the PC steel material are used. It is preferably used.

The method of wiring the PC steel material according to the present embodiment using the wiring device 100 exemplified above is a long PC steel material for introducing a tension force when constructing a prestressed concrete structure by a post-tension method. A method of wiring the 200, in which the PC steel 200 is aligned with at least a part (approximately half a circumference in FIG. 1) of a disk-shaped member (main sheave 110) having a curvature corresponding to the PC steel 200. In this state, by advancing the PC steel material 200 in the long longitudinal direction in the direction indicated by the arrow X by the manual force of the worker S, it corresponds to the outer diameter shape (outer circumference shape) of the disk-shaped member (main sheave 110). By bending the PC steel material 200 in this way and bending the PC steel material 200 so that the PC steel material 200 is in the Y direction indicated by the arrow, and by advancing the PC steel material 200 in the longitudinal direction by the manual force of the worker S, a disk-shaped member (main sheave). With the insertion step of inserting the PC steel material 200, which is separated from the disk-shaped member (main sheave 110) from the state along 110), into the hollow sheath 310 arranged (buried) in the concrete structure 300. Is a method that includes.

In the present embodiment, the main sheave 110 is adopted as such a disk-shaped member, and in the bending step described above, the PC steel material 200 is applied to the outer diameter of the main sheave 110 by the guide rollers 120 and 130. The PC steel material 200 is bent by sandwiching it.
In FIG. 1, the PC steel material 200 is advanced only by the human power of the worker S, but the present invention is not limited to such an advance method, and the mechanical power other than the human power is used in the bending step. The PC steel material 200 may be advanced in the long longitudinal direction using the above (that is, mechanical power other than the human power of the worker S is used). As such an embodiment, for example, in a bending step, a method of extruding a PC steel material 200 in a long longitudinal direction using mechanical power (FIG. 2 (B)) and a disk-shaped member (main) using mechanical power. The PC steel material 200 is advanced in the long longitudinal direction by at least one of the methods of rotating the sheave 110) (FIG. 2C).

More specifically, instead of or in addition to the method of advancing the PC steel material 200 only by human power in the direction of arrow W (1) indicated by the operator S as shown in FIG. 2 (A), or in addition, FIG. 2 (B). ), An electric (electrically powered) tire type strand pusher 600 may be used, or an electric motor (motor) for rotating the main sheave 110 may be used as shown in FIG. 2 (C). In this case, mechanical power may be used together with the human power of the worker S, or other types of mechanical power (for example, mechanical power that applies a pulling force instead of pushing out to the PC steel material 200) may be used. May be combined as appropriate.

In the tire type strand pusher 600 shown in FIG. 2B, a pair of electric tires 610 and electric tires 620 sandwiching a PC steel material 200 are connected to at least one electric tire by electric power (motor) in the direction W (2) and in the direction of arrow W (2). This is a method of advancing the PC steel material 200 by rotating it in the direction of arrow W (3).
In the method of rotating the main sheave 110 shown in FIG. 2 (C), the main sheave 110 sandwiching the PC steel material 200 together with the guide rollers 120 and 130 described with reference to FIG. ) Is a method of advancing the PC steel material 200 by rotating it in the direction. Instead of or in addition to the method of rotating the main sheave 110 in this way, a method of rotating the guide rollers 120 and 130 in predetermined directions by electric power (motor) may be adopted.

When the PC steel material 200 is sandwiched between the main sheave 110 and the guide rollers 120 and 130 in this way, for example, the following two methods can be adopted as the preparatory steps executed before the bending step.
As shown in FIG. 3, in the preparatory step executed before the bending step, the PC steel material 200 is brought into contact with the outer diameter of the main sheave 110 and sandwiched by the insertion side guide roller 140 along the outer diameter of the main sheave. By moving the insertion side guide roller 140 to a position where the PC steel material 200 is separated, the PC steel material 200 is set on the main sheave 110. More specifically, in this case, the insertion side guide roller 140 having a function different from that of the insertion side guide roller 130 is configured to be movable in the direction of arrow Z (1) shown in FIG. As shown in FIGS. 3A to 3C, the insertion side guide roller 140 sandwiching the PC steel material 200 with the main sheave 110 is in the direction of arrow Z (1) (here, approximately half of the main sheave 110). The rotation axis of the insertion side guide roller 140 moves (by the amount of rotation). Although the pull-out side guide roller 120 rotates, it is not necessary for the rotation axis to move as in the insertion-side guide roller 140.

Further, as shown in FIG. 4, in the preparatory step executed before the bending step, the starting end of the PC steel material 200 is fixed to the outer diameter of the main sheave 110 by the fixing jig 210, and the PC steel material 200 is fixed to the drawer side guide roller. The PC steel material 200 is set on the main sheave 110 by sandwiching it between 120 and rotating the main sheave 110 (by human power or mechanical power). More specifically, in this case, the insertion side guide roller 150 having a function different from that of the insertion side guide roller 130 and the insertion side guide roller 140 is configured to be movable in the direction of arrow Z (2) shown in FIG. As shown in FIGS. 4 (A) to 4 (C) in chronological order, the PC steel material 200 whose starting end is fixed by the fixing jig 210 moves in the direction of arrow R (1) due to the rotation of the main sheave 110. Moving. Until the start end of the PC steel material 200 exceeds the position of the insertion side guide roller 150, the insertion side guide roller 150 is separated from the outer periphery of the main sheave 110 by at least the size of the fixing jig 210, and the PC steel material 200 is separated from the insertion side guide roller 150 by at least the size of the fixing jig 210. When the starting end exceeds the position of the insertion side guide roller 150, the insertion side guide roller 150 approaches the outer periphery of the main sheave 110 (the insertion side guide roller 150 moves the rotation axis in the direction of arrow Z (2)). , The PC steel material 200 is sandwiched between the main sheave 110 and the insertion side guide roller 150. Although the pull-out side guide roller 120 rotates, its rotation axis does not need to move.

In this way, the PC steel material 200 whose traveling direction is changed from the arrow X direction to the arrow Y direction by being bent to a desired curvature in the bending step has a bending habit given in the bending step in the insertion step. In such a case, this bending habit may be caught on the inner wall of the sheath 310 and become an insertion resistance into the sheath 310. Therefore, in the wiring method of the PC steel material according to the present embodiment, the bending habit that is attached to the PC steel material 200 in the bending step and remains after the bending step is corrected between the bending step and the insertion step. It is also preferred to include additional correction steps.

More specifically, as shown in FIG. 5, a straightening portion 700 is installed between the insertion side guide roller 130 and the inlet of the sheath 310. The straightening portion 700 is composed of a plurality of straightening rollers 710, 720, and 730, and is provided with the PC steel material 200 sandwiched so as to sandwich the PC steel material 200. Here, the straightening roller 710 and the straightening roller 720 are arranged side by side, and the straightening roller 730 is provided on the opposite side of the PC steel material 200 between the straightening roller 710 and the straightening roller 720. That is, the straightening rollers 710, 720, and 730 are arranged in a staggered manner and sandwich the PC steel material 200. The straightening rollers 710, 720, and 730 rotate while sandwiching the PC steel material 200 in a predetermined direction, respectively. Here, the straightening roller 710 and the straightening roller 720 rotate in the direction of arrow R (4) and in the direction of straightening roller 730 arrow R (4), respectively. In this case, the rotation may be either a free rotation that rotates as the PC steel material 200 advances without power being applied, or a forced rotation that rotates as power is applied.

In the above-described embodiment, the direction in which the PC steel material 200 begins to follow the main sheave 110 (direction X) and the direction in which the PC steel material 200 begins to separate from the main sheave 110 (direction Y) are abbreviated. Although modified by 180 degrees, the invention is not limited to such angles. It suffices as long as it can realize a suitable wiring method in a narrow construction place. For example, in the bending step, the PC steel material 200 is aligned with at least 1/6 of the outer diameter peripheral length of the disk-shaped member (main sheave 110). Therefore, the direction in which the PC steel material 200 begins to run along the disk-shaped member (main sheave 110) and the direction in which the PC steel material 200 begins to separate from the disk-shaped member (main sheave 110) are changed by 60 degrees or more. Is preferable. By changing the direction by 60 degrees or more along 1/6 or more of the outer peripheral circumference, it is possible to exhibit the effect of facilitating the construction in a narrow place. PC steel material from the direction in which the PC steel material 200 started to follow the disk-shaped member (main sheave 110) (direction X indicated by arrows in FIGS. 6 (A) to 6 (D)) and the disk-shaped member (main sheave 110). As a matter of course, the upper limit of the change angle from the direction in which the 200 begins to separate (the Y direction indicated by FIGS. 6 (A) to 6 (D)) is 180 degrees. That is, for example, as shown in FIG. 6 (A), the direction is changed by 60 degrees from the arrow X direction to the arrow Y direction along about 1/6 of the outer diameter circumference, and as shown in FIG. The direction is changed by 90 degrees from the arrow X direction to the arrow Y direction along about 1/4 of the circumference, and as shown in FIG. 6C, the arrow X is along about 1/3 of the outer circumference. Change the direction from the direction to the arrow Y direction by 120 degrees, and change the direction from the arrow X direction to the arrow Y direction by 180 degrees along about 1/2 of the outer diameter circumference as shown in FIG. 6 (D). Therefore, it is possible to exhibit the effect of facilitating the construction in a narrow place.

By the way, as described above, a long PC steel material 200 for introducing a tension force when constructing a prestressed concrete structure by a post-tension method is provided with a curvature corresponding to the PC steel material 200 in a bending step. With the PC steel material 200 aligned with at least a part of the outer diameter of the disk-shaped member (main sheave 110), the PC steel material 200 is advanced in the long longitudinal direction so as to correspond to the shape of the outer diameter. The PC steel material 200 is bent. By this bending step, the PC steel material 200 is bent with a curvature corresponding to the PC steel material 200. Here, if the PC steel material 200 is bent extremely (if it is bent with a small curvature), for example, the epoxy resin covering the outer layer of the PC steel material 200 may be damaged. There is sex. In order to avoid such a problem, in this bending step, the PC steel material 200 is formed by using a disk-shaped member (main sheave 110) having a curvature equal to or greater than the maximum allowable curvature set for the PC steel material 200. I'm bending. Furthermore, where if the PC steel member 200 is a line of epoxy resin coating PC strand (ECF strands), the bending step, a circle with a 32-fold or more the radius of the diameter of the wire from the ET epoxy resin coating PC strand The PC steel material 200 is bent using a plate-shaped member (main sheave 110).
[Specific wiring equipment and wiring method]
The wiring device and the wiring method will be described more specifically with reference to FIG. 7 showing a wiring method adopting the prior art and FIGS. 8 and 9 showing the wiring method according to the present embodiment.

The wiring method of the PC steel material according to the present embodiment and the wiring device of the PC steel material for realizing this wiring method are as described above, but will be described in more detail below. The wiring device and wiring method shown below are merely examples of the present invention, and the present invention is not limited to the wiring device and wiring method shown below.
First, with reference to FIG. 7, a wiring method adopting the prior art will be described. In the prior art, instead of the wiring method using the wiring device as described above, for example, a semi-circular pipe 800 made of polyethylene or steel is fixed, and the PC steel material 200 is sandwiched by the tire type strand pusher 600. By rotating the pair of electric tires 610 and the electric tires 620 in the direction of arrow W (2) and the direction of arrow W (3) by electric power (motor), the PC steel material 200 is installed in the pipe 800. The direction of the PC steel material 200 was changed by approximately 180 degrees (the angle between the arrow X direction and the arrow Y direction in FIGS. 6 (A) to 6 (D)).

However,
-When ECF strand 28.6 mm diameter was adopted as the PC steel material 200 and a polyethylene pipe with an outer diameter of 76 mm and a radius of curvature of 900 mm was adopted as the pipe 800, the PC steel material 200 advanced about 1/3 of the pipe 800. The tip of the 200 sank into the pipe 800 and could not be advanced any further.
-When the ECF strand 28.6 mm diameter was adopted as the PC steel material 200 and the steel pipe with the outer diameter 89.1 mm and the radius of curvature 900 mm was adopted as the pipe 800, (the material of the pipe 800 is not made of PE but made of steel. Therefore, although the tip of the PC steel material 200 did not sink into the pipe 800, it could not be advanced when the PC steel material 200 advanced about 1/3 of the pipe 800. For this reason, it is difficult to insert the PC steel material 200 into the sheath 310 in a narrow construction place because the PC steel material 200 cannot be bent favorably by the conventional technique shown in FIG. 7.

On the other hand, when the wiring device 1000 shown in FIGS. 8 and 9 which embodies the above-mentioned wiring device is used, the PC steel material 200 could be bent in the bending step without any problem. This will be described in detail below.
As shown in FIGS. 8 and 9, in the wiring device 1000, both the pull-out side guide roller 1120 (corresponding to the pull-out side guide roller 120) and the insertion side in which the positions of the rotation axis (this rotation axis is the vertical axis) are fixed are fixed. Advance the main sheave 1110 (corresponding to the main sheave 110) in the direction of arrow A (1) with respect to the guide roller 1130 (corresponding to the insertion side guide roller 130) and these drawer side guide rollers 1120 and the insertion side guide roller 1130. Alternatively, it is provided with a pneumatic device (here, an air cylinder 1100) that retracts in the direction of arrow A (2). Here, in FIG. 8, approximately 1/3 of the outer diameter peripheral length of the main sheave 1110 is approximately 1/3, and in FIG. 9, approximately 1/3 or approximately 1/2 of the outer diameter peripheral length of the main sheave 1110 is along the PC steel material 200. , The traveling direction of the PC steel material 200 corresponds to the conversion (approximately 120-degree conversion corresponding to FIG. 6 (C) in FIG. 8, approximately 120-degree conversion corresponding to FIG. 6 (C) or FIG. 6 (D) in FIG. 9). Approximately 180 degrees conversion).

The main sheave 1110 is supported by a rotation axis 1112 (a vertical axis corresponding to the rotation axis 112) so as to be rotatable in the direction of arrow R (1). The stroke length of the air cylinder 1100 differs depending on how much the PC steel material 200 conforms to the outer diameter peripheral length of the main sheave 1110, but the PC steel material 200 is aligned with at least 1/6 and the PC steel material 200 is aligned with the main sheave 1110. It is the same as the above that it is preferable that the direction in which the PC steel material 200 starts to separate from the main sheave 1110 is changed by 60 degrees or more. In this wiring device 1000, the rotation axes of the drawer side guide roller 1120, the insertion side guide roller 1130, and the main sheave 1110 are vertical axes (axises extended in the vertical direction), but the present invention rotates in this way. The direction of the axis is not limited to the vertical direction.

As shown in FIG.
When the stroke length of the air cylinder 1100 is L (B) shown in the figure, the main sheave 11
10 can advance from the initial position 1110A to the first forward position 1110B, and the PC steel material 200 is aligned with about 1/3 of the outer diameter peripheral length of the main sheave 1110, and the PC steel material 200 in the initial state 200A is bent by a bending step. The PC steel material 200 shown as the conversion state 200B can be changed to the PC steel material 200 whose traveling direction is changed by approximately 120 degrees.
When the stroke length of the air cylinder 1100 is L (C) shown in the figure, the main sheave 1110 can advance from the initial position 1110A to the second forward position 1110C, and the PC steel material 200 can move the PC steel material 200 to the outer diameter peripheral length of the main sheave 1110. The PC steel material 200 in the initial state 200A can be changed to the PC steel material 200 shown as the conversion state 200C by the bending step, and the traveling direction thereof is changed to the PC steel material 200 whose direction is changed by approximately 180 degrees. (It is assumed that the PC steel material 200 is sandwiched between the main sheave 1110, the drawer side guide roller 1120, and the insertion side guide roller 1130 at any stroke length).

If, instead of the air cylinder 1100, a linear guide and a drive motor capable of stopping at a plurality of positions are used to realize a plurality of stroke lengths, for example, a PC steel material can be used according to the size of the construction site. The length of the 200 can be changed along with the outer peripheral circumference of the main sheave 1110, and the traveling direction of the PC steel 200 can be changed to the size of the construction site as desired (any of them). The stroke length is the same as described above in that the PC steel material 200 is sandwiched between the main sheave 1110, the drawer side guide roller 1120, and the insertion side guide roller 1130).

The wiring method according to the present embodiment using the wiring device 1000 shown in FIGS. 8 and 9 will be described. The stroke length of the air cylinder 1100 will be described as L (C).
This wiring method is a method of wiring a long PC steel material 200 for introducing a tension force when constructing a prestressed concrete structure by a post-tension method.
If the main sheave 1110 is not in its initial position 1110A, the air cylinder 1100 is retracted in the direction of arrow A (2) and the main sheave 1110 is moved to its initial position 1110A.
-The PC steel material 200 shown as the initial state 200A is set in the main sheave 1110.-The air cylinder 1100 is advanced in the direction of arrow A (1), and the main sheave 1110 is moved to the second advance position 1110C. The PC steel material 200 is sandwiched between the drawer side guide roller 1120, the insertion side guide roller 1130, and the main sheave 1110.
In this way, the PC steel material 200 is aligned with at least a part of the outer diameter of the main sheave 1110 having a curvature corresponding to the PC steel material 200 (approximately 1/2 because the stroke length in FIG. 9 is L (C)). In this state, the PC steel material 200 is advanced in the long longitudinal direction by the tire type strand pusher 600 in the X direction indicated by the arrow so as to correspond to the shape of the outer diameter of the disk-shaped member (main sheave 110). The PC steel material 200 is bent to the state shown in the conversion state 200C, and the PC steel material 200 is bent so that the traveling direction of the PC steel material 200 is the arrow Y direction (bending step).
-By advancing the PC steel material 200 in the longitudinal direction by the tire type strand pusher 600, the PC steel material 200 that has been separated from the main sheave 1110 from the state along the main sheave 1110 is arranged in the concrete structure 300 ( Includes insertion into (embedded) hollow sheath 310 (insertion step).

As described above, according to the wiring method of the PC steel material according to the present embodiment, it is a PC steel material that introduces a tension force in the prestressed concrete post-tension method, and the PC steel material has poor flexibility and is a narrow construction site. Even so, the PC steel material can be suitably wired to the sheath during construction.
It should be noted that the embodiments disclosed this time are exemplary in all respects and are not considered to be restrictive. The scope of the present invention is shown by the scope of claims rather than the above description, and it is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

The present invention is preferable for a technique of wiring a long PC steel material for introducing a tension force when constructing a prestressed concrete structure by a post-tension method, and the PC steel material is inflexible and is a narrow construction site. However, it is particularly preferable in that the PC steel material can be suitably wired to the sheath during construction.

100 Wiring device 110 Main sheave 112 Rotating shaft 120 Drawer side guide roller 130 Insertion side guide roller 200 PC steel 300 Concrete structure 310 Sheath 400 Existing structure 500 Scaffolding 510 Stand 600 Tire type strand pusher 1000 Wiring device

Claims (8)

It is a method of wiring a long PC steel material to introduce tension when constructing a prestressed concrete structure by the post tension method.
By advancing the PC steel material in the long longitudinal direction in a state where the PC steel material is aligned with at least a part of the outer diameter of the disk-shaped member having a curvature corresponding to the PC steel material, the outside Bending step of bending the PC steel material so as to correspond to the shape of the diameter,
By advancing the PC steel material in the longitudinal direction, the PC steel material that has been separated from the disk-shaped member from the state along the disk-shaped member is transferred to the hollow sheath arranged in the concrete structure. Insert step to insert and
Only including,
The disk-shaped member is a main sheave and
In the bending step, the PC steel material is sandwiched by a guide roller on the outer diameter of the main sheave to bend the PC steel material.
Prior to the bending step, the PC steel material is brought into contact with the outer diameter of the main sheave, sandwiched between the guide rollers, and the guide roller is moved along the outer diameter of the main sheave to the separated position. A method of wiring a PC steel material, further comprising a preparatory step of setting the PC steel material on the main sheave. It is a method of wiring a long PC steel material to introduce tension when constructing a prestressed concrete structure by the post tension method.
By advancing the PC steel material in the long longitudinal direction in a state where the PC steel material is aligned with at least a part of the outer diameter of the disk-shaped member having a curvature corresponding to the PC steel material, the outside Bending step of bending the PC steel material so as to correspond to the shape of the diameter,
By advancing the PC steel material in the longitudinal direction, the PC steel material that has been separated from the disk-shaped member from the state along the disk-shaped member is transferred to the hollow sheath arranged in the concrete structure. Insert step to insert and
Including
The disk-shaped member is a main sheave and
In the bending step, the PC steel material is sandwiched by a guide roller on the outer diameter of the main sheave to bend the PC steel material.
Prior to the bending step, the PC steel material is fixed to the outer diameter of the main sheave, the PC steel material is sandwiched between the guide rollers, and the main sheave is rotated to obtain the PC steel material into the main sheave. Wiring method for PC steel, including further preparatory steps to set up. In the bending step, the PC steel material is aligned with at least 1/6 of the outer diameter peripheral length of the disk-shaped member, and the direction in which the PC steel material is started to be aligned with the disk-shaped member and the disk-shaped member The wiring method for a PC steel material according to claim 1 or 2 , wherein the direction in which the PC steel material begins to separate is changed by 60 degrees or more. The method for wiring a PC steel material according to any one of claims 1 to 3 , wherein in the bending step, the PC steel material is advanced in the long longitudinal direction by using mechanical power other than human power. In the bending step, at least one of a method of extruding the PC steel material in the long longitudinal direction using the mechanical power and a method of rotating the disk-shaped member using the mechanical power. The wiring method for a PC steel material according to claim 4 , wherein the PC steel material is advanced in the longitudinal direction of the long length. Claims 1 to 5 further include a straightening step between the bending step and the insertion step to correct the bending habit that is attached to the PC steel material in the bending step and remains after the bending step. The method for wiring a PC steel material according to any one of the above. The PC according to any one of claims 1 to 6 , wherein the bending step bends the PC steel material using a disk-shaped member having a curvature equal to or higher than a maximum allowable curvature set for the PC steel material. Wiring method for steel materials. The PC steel material is an epoxy resin-coated PC steel stranded wire.
The bending step, before Symbol with disk-shaped member having a 32 times or more the radius of the diameter of the wire from the epoxy resin-coated PC steel bending the PC steel according to any one of claims 1 to 6 Wiring method for PC steel.

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