PC tendon connector

Abstract

To provide a connector which is simple in assembly and disassembly of a connector, improves working efficiency, and achieves reduction of manufacturing time and a manufacturing cost of a PC member.SOLUTION: A connector is composed of a housing part 10 having a hollow part 11, wedge body holder parts 20 formed on both end sides of the housing part 10, a wedge body 30 for holding a PC tendon T, and a set jig 40 for pressing the wedge body 30. The set jig 40 includes pressing parts 42 formed on both ends, and the pressing part includes a horseshoe-shaped space part 41 to which the PC tendon T can be inserted, and a connection part 43 for connecting between the pressing parts. The set jig 40 is arranged from an opening 12 in the state where the PC tendon T is sandwiched by the horseshoe-shaped space part 41 of the set jig 40, and the pressing part 42 of the set jig 40 can press the wedge body 30 to the wedge body holder part 20 in the state where the wedge body 30 holds the PC tendon T.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a connector for PC tendons, and in particular to a connector for PC tendons used when connecting a tensioning device to PC tendons or connecting PC tendons to each other in the manufacture of PC components using PC tendons. [Background technology]

[0002] Generally, connectors for PC tendons are used as metal fittings when axially connecting PC tendons such as tension rebars and PC steel wires used in PC components.

[0003] Conventionally, PC members using PC tendons, in which prestress is introduced by the pretensioning method, are manufactured using a formwork for PC members. In other words, to manufacture multiple PC members, a specified number of PC tendons are hung in specified positions in the formwork, and concrete is poured into the formwork to form them. In this case, multiple formwork and PC tendons of a specified length are placed and used between strong reaction bodies installed at both ends of a section of several dozen meters to several tens of meters, and it is necessary to connect the PC tendons to the tensioning devices and to connect the PC tendons to each other.

[0004] Generally, to manufacture PC components using multiple formwork, formwork arranged in a row is used, and PC tendons are arranged in this row of formwork. One end of the arranged PC tendons is fixed to a reaction body, and the other end is connected to a tensioning device that is tensioned by a jack, and the PC tendons are connected to each other by aligning them in the axial direction, and each connection (joint) is made via a connector.

[0005] In other words, for example, when manufacturing PC components (prestressed concrete), the connectors of the PC tendons are placed outside the formwork in which the PC components are manufactured, and the PC tendons are placed into the formwork while still under tension. Concrete is then poured into the formwork, and when the concrete has developed a predetermined strength, the tension in the PC tendons is released and the connectors of the PC tendons are removed, and these connectors are then reused.

[0006] A commonly used connector for PC tendons is a cylindrical metal body with two or three separate conical wedges with blades attached to both ends, which are connected by sliding the tension of the PC tendons, causing the blades of the wedges to bite into the PC tendons.

[0007] For example, Patent Document 1 discloses a technology for a PC steel strand connection structure comprising a cylindrical coupler having a screw-connecting gripping portion in the center of its outer periphery and female threads screwed into the inner walls at both left and right ends, a pair of left and right chuck bodies having male threads on the outer periphery of the front part of the cylinder that screw together with the female threads and having a tapered insertion inside the cylinder that reduces in diameter towards the rear end, and split wedges that are inserted into the insertion portions of the chuck bodies and grip the PC steel strands with their inner wall surfaces, in which a high-strength metal cylinder is interposed between the right wedge end face and the left wedge end face of each chuck body in contact with both end faces of the wedges.

[0008] Generally, a PC tendon is subjected to tension of several tens of kilonewtons per tendon, so the wedge that engages with the PC tendon must minimize slippage while ensuring safety. Also, since operability during manufacturing is closely related to work efficiency, the shape and length of the wedge blade are determined for each steel diameter of the PC tendon. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] JP 2004-100444 A Summary of the Invention [Problem to be solved by the invention]

[0010] When the connectors for conventional PC tendons are used to connect high-strength rebars together, the connectors and wedges are firmly bonded, causing the high-strength rebar to bite into the wedges provided in the connectors, which creates the inconvenience of making it difficult to remove the high-strength rebars after the tension is released.

[0011] In addition, when connecting PC tendons together, the connectors that have been used up until now have required the PC tendons to be pulled and moved before being inserted into the connectors, and the inside of the connectors cannot be seen, resulting in poor work efficiency. Also, when connecting the tensioning device or reaction body to the PC tendons using connectors, the connection status cannot be visually confirmed, resulting in poor work efficiency. Thus, there has been a demand for a connector for PC tendons that allows easy removal of the high-strength rebar from the connector and easy removal of the wedge and the high-strength rebar.

[0012] In addition, there was a demand for a connector technology that could efficiently connect PC tendons together without pulling and moving the PC tendons when connecting them using a connector.

[0013] The object of the present invention is to provide a connector for PC tendons that can be easily assembled and disassembled when connecting a tensioning device or a reaction body to a PC tendon, or when connecting PC tendons to each other, thereby improving work efficiency and enabling a reduction in the manufacturing time and manufacturing costs of PC components. [Means for solving the problem]

[0014] The above-mentioned problem is solved by the connection tool for PC tendons according to the present invention, which is a connection tool for PC tendons for connecting PC tendons, and the connection tool is composed of a housing part having a hollow part constituting a main body, a wedge holder part for holding a wedge on at least one of one end side and the other end side of the housing part, the wedge that is arranged on the wedge holder part and holds the PC tendon, and a setting jig for pressing the wedge, and the housing part is composed of the hollow part communicating with the wedge holder part, an opening formed in a part of the hollow part and open to the atmosphere, and a setting jig for pressing the wedge. The problem is solved by the fact that the setting jig comprises a wedge body holder installation portion to which a body holder portion is attached, and the setting jig comprises a pressing portion formed on at least one end side of both ends, a placement portion in which the PC tension material can be placed in the pressing portion, and a connecting portion that connects the pressing portions, and when the setting jig is placed from the opening of the housing portion, the PC tension material is positioned and attached in the placement portion of the setting jig, and the wedge can be pressed against the wedge body holder portion by the pressing portion of the setting jig while holding the PC tension material.

[0015] In the PC tendon connector of the present invention, an opening open to the atmosphere is formed in the housing of the connector, allowing the PC tendon and wedge body to be easily moved between the outside and inside of the connector while visually inspecting them, and making it possible to easily engage the wedge body and PC tendon inside the connector.

[0016] In addition, the PC tendons can be held in the connector by moving the connector itself, without having to pull and move the PC tendons. This means that the connector can be easily assembled and disassembled during the manufacture of the PC member, shortening the manufacturing time and reducing the manufacturing costs of the PC member that uses the PC tendons.

[0017] In addition, the structure of the connectors for the PC tendons is extremely simple and highly durable, making it easy to replace and manage parts, while also improving work efficiency and making it possible to reduce the overall manufacturing costs of PC components. It is preferable that the PC tendons are arranged with their axial directions aligned on one end side and the other end side of the housing part, so that the axial directions are aligned and the connection can be made, and tension can be applied to the PC tendons without misalignment in the axial direction.

[0018] In this case, it is preferable that the wedge holder portion is configured to include a PC tendon insertion hole provided on one end side of the wedge holder portion, a wedge mounting hole provided on the other end side of the wedge holder portion, a knob portion formed on the PC tendon insertion hole side, and a male thread portion formed on the outer periphery continuous with the knob portion.

[0019] When configured in this manner, the wedge holder portion can be assembled integrally with the housing portion by rotating the knob portion and screwing the wedge holder portion into the female threaded portion of the housing portion with the male threaded portion formed on the outer periphery continuous with the knob portion.

[0020] In addition, the wedge body may be preferably composed of a plurality of segments divided circumferentially, a blade-shaped portion formed on the inner surface of the segments, a PC tendon through hole through which the PC tendon formed by the plurality of segments is inserted, and a wedge body connector that integrates the segments. In this way, since the wedge body is composed of multiple segments divided circumferentially, even if the blade-shaped portion of the wedge body is biting into the PC tendon, it is easy to peel each segment individually from the PC tendon.

[0021] Furthermore, it is preferable that the pressing part of the setting jig is provided with a positioning part in which the PC tendons can be placed. Since the pressing part is provided with a positioning part in which the PC tendons can be placed, when the PC tendons are connected to each other, the PC tendons are restricted by the positioning parts formed in the pressing parts at both ends, and can be placed so that their axial directions are aligned.

[0022] At this time, the pressing portion is tapered from the wedge pressing surface toward the connecting portion on the free end side. That is, it is preferable that the free end side (the surface opposite the connecting portion) is tapered from the wedge pressing surface toward the connecting portion, and such a tapered portion of the wedge pressing portion makes it easy to position the setting jig between the wedges, and the connecting portion of the setting jig can be forcibly pressed with a hammer or the like against the wedge pressing surface to reliably fit the wedge into the wedge holder portion, thereby eliminating play between the wedge and the wedge holder portion.

[0023] By using the setting jig, the wedge can be securely held in the housing, and the PC tendons can be securely connected linearly in the axial direction. In other words, the pressing part of the setting jig can reliably press the wedge against the wedge holder, eliminating play and reducing set loss. Effect of the Invention

[0024] According to the PC tendon connector of the present invention, an opening open to the atmosphere is formed in the connector, allowing the wedge to be easily moved between the outside and inside of the connector, making it possible to connect the PC tendon to the wedge inside the connector while visually inspecting the wedge and the PC tendon.

[0025] Furthermore, without having to pull and move the PC tendon, the connector itself can be moved and the wedge and the PC tendon can be engaged with the connector while being visually inspected. In addition, when manufacturing PC components, it becomes easy to connect and disassemble PC tendons to each other, and to connect and disassemble PC tendons to threaded rebars attached to threaded holders.In addition, because it becomes possible to easily assemble and disassemble connectors for PC tendons, it becomes possible to shorten the manufacturing time and reduce the manufacturing costs of PC components while ensuring the strength of the connections.

[0026] In addition, the structure of the connectors for the PC tendons and threaded rebars is extremely simple and highly durable, making it easy to replace and manage parts and improving work efficiency, which makes it possible to reduce the overall manufacturing costs of PC components.

[0027] In addition, the setting jig makes it possible to easily attach the wedge by pressing it against the wedge holder positioning section of the housing section, and makes it possible to connect the PC tendons to each other and the PC tendons to the screw reinforcing bars in a linear manner in the axial direction when connecting the PC tendons to each other and the PC tendons to the screw reinforcing bars. In this way, the setting jig can eliminate play in the wedge body and reduce set loss, thereby ensuring the quality of the manufactured PC components. [Brief description of the drawings]

[0028] [Figure 1] FIG. 1 is a perspective view illustrating one embodiment of a connector according to the present invention. [Diagram 2] 13 is a plan view illustrating the housing part of the connector according to the present invention with the wedge holder part attached thereto. FIG. [Diagram 3] FIG. 2 is an exploded explanatory view of FIG. [Figure 4] FIG. 2 is an explanatory diagram of a wedge holder portion in FIG. 1. [Figure 5A] 1A is a perspective view of a wedge body, and FIG. 1B is a perspective view of the engagement with a PC tendon. [Figure 5B] FIG. 5B is an explanatory diagram of the wedge of FIG. 5A. [Figure 5C] FIG. 5B is an explanatory diagram of a divided body constituting the wedge body of FIG. 5A. [Figure 5D] 5B shows the O-ring of FIG. 5A, in which (a) is a plan view and (b) is a side view in the direction of the arrow in (a). [Figure 6A] FIG. 2 is a perspective view of a setting jig according to an embodiment of the present invention. [Figure 6B] FIG. 6B is a view seen from the direction of the arrow in FIG. 6A. [Figure 6C] 6B is an explanatory diagram of the mounting of the setting jig in FIG. 6A, and FIG. [Figure 7A] 13(a) to (d) are explanatory diagrams of the assembly status of the PC tendon connector. [Figure 7B] 4(e) to 4(h) are explanatory diagrams of the assembly status of the PC tendon connector. [Figure 7C]13(i) to 13(k) are explanatory diagrams of the assembly status of the PC tendon connector. [Figure 7D] 13(l) to 13(m) are explanatory diagrams of the assembly status of the PC tendon connector. [Figure 8A] FIG. 11 is an explanatory diagram of the use of a PC tendon connector when manufacturing one PC member. [Figure 8B] FIG. 11 is an explanatory diagram of the use of PC tendon connectors when manufacturing multiple PC components. [Figure 9A] 13(a) to 13(d) are explanatory diagrams showing the dismantling of a PC tendon connector. [Figure 9B] 4(e) to 4(h) are explanatory diagrams showing the dismantling of the PC tendon connector. [Figure 9C] 13(i) to 13(l) are explanatory diagrams showing the dismantling of the PC tendon connector. [Figure 10] FIG. 11 is an explanatory diagram of a connector showing a second embodiment. [Figure 11] FIG. 11 is an explanatory diagram of the connection between the connector of FIG. 10 and a PC tendon. [Figure 12] FIG. 13 is an explanatory diagram of the state when the setting jig is attached. [Figure 13] 13 is an explanatory diagram of a usage state when a PC member is manufactured using the connector of the second embodiment. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] An embodiment of the present invention (hereinafter, this embodiment) will be described below with reference to the drawings. Note that the members, arrangements, etc. described below do not limit the present invention, and can be modified in various ways within the scope of the present invention, and the dimensions described below are merely examples.

[0030] As shown in Figures 1 and 3, the connector 1 of the PC tendon T of this embodiment has as its main components a housing portion 10, a wedge holder portion 20, a wedge 30, a setting jig 40, and the like.

[0031] The casing 10 of this embodiment constitutes the main body of the connector 1 for PC tendons, is formed in a cylindrical shape, has a longitudinal length of about 260 mm, and an outer diameter of about 65 mm to 80 mm. It is made of steel. The dimensions of the casing 10 and the various dimensions of the components other than the casing 10 described below can take various values ​​within a certain range as long as they are in line with the spirit of the present invention, and the dimensions are not fixed or limited. As shown in FIG. 2, the housing 10 includes a hollow portion 11, an opening 12, a wedge holder installation portion 13, and a wedge placement stand 50. As shown in FIG.

[0032] The hollow portion 11 in this embodiment is formed approximately in the center of the housing portion 10 in the longitudinal direction, and this hollow portion 11 is located between the wedge body holder installation portions 13 formed on both end sides of the housing portion 10, and communicates with the wedge body holder installation portions 13. This hollow portion 11 also serves as a space for mounting a setting jig 40, which will be described later.

[0033] The size of the hollow portion 11 is approximately 160 mm in the longitudinal direction of the housing portion 10, approximately 50 mm in the lateral direction perpendicular to the longitudinal direction, and approximately 40 mm in the height direction from the bottom surface of the housing portion 10 so that the setting jig 40 can be attached to the housing portion 10. The opening 12 in this embodiment is configured by cutting out a part (the upper side in this example) of the hollow portion 11 in a substantially rectangular shape, and is formed so as to be open to the atmosphere.

[0034] As shown in Figs. 2 and 3, the wedge holder installation sections 13 of this embodiment are formed on both longitudinal end sides of the housing section 10, and are hollow so that the wedge holder sections 20 can be attached. That is, in this embodiment, a female thread portion 13b is screwed onto the inner periphery of the wedge holder installation portion 13 so that the male thread portion 24 of the wedge holder portion 20 can be screwed in. The size of this female thread portion 13b is formed to match the male thread portion 24 of the wedge holder portion 20, and in this embodiment, the length is about 40 mm and the inner diameter is about 50 mm.

[0035] 2, the wedge placement base 50 is composed of a wedge insertion groove 50a and a setting jig installation surface 50b. The wedge insertion groove 50a is located at the bottom of the housing 10, between the wedge insertion opening 23a formed on one end side and the wedge insertion opening 23a formed on the other end side, and is formed by a long groove in the axial direction. Further, the setting jig installation surface 50b is formed on the lower side of the casing 10, above the wedge insertion groove 50a.

[0036] The setting jig installation surface 50b abuts against the free end side end of the wedge pressing portion 42 of the setting jig 40 when the setting jig 40 described later is struck with a hammer or the like from the top of the connecting portion (striking portion) 43 and inserted between the wedge bodies 30. After the wedge 30 is connected to the PC tendon T at the position of the hollow portion 11, it is moved to the wedge insertion opening 23a while sliding along the wedge insertion groove 50a, and is inserted into the tapered portion 23b. The wedge insertion groove 50a is approximately equal to the larger outer diameter of the wedge 30, but is formed slightly larger than the larger outer diameter of the wedge 30 so that the wedge 30 can slide.

[0037] As described above, the wedge holder part 20 of this embodiment holds the wedge 30 and is provided on one end side and the other end side of the housing part 10. The wedge holder part 20 is made of steel, and its size is about 60 mm in length in the longitudinal direction and about 50 mm in outer diameter. The wedge holder portion 20 is formed in a cylindrical shape, and the portion about 20 mm from the PC tendon insertion port 22 serves as a knob portion 25 that is not threaded. A male thread portion 24 is formed continuous with this knob portion 25, and this male thread portion 24 is configured so as to be able to screw into the female thread portion 13b formed on the wedge holder installation portion 13 described above.

[0038] More specifically, the wedge holder portion 20 is formed with a PC tendon insertion hole 21, a wedge mounting hole 23, a male thread portion 24, and a knob portion 25. A PC tendon insertion opening 22 is formed on the end side of the knob portion 25, and the size of this PC tendon insertion opening 22 is determined according to the thickness of the PC tendon T, but in this embodiment, the hole diameter is set to about 16 mm to match the PC tendon T. Each wedge holder portion 20 is screwed to the wedge holder installation portion 13 at both ends of the housing portion 10, and the wedge holder portion 20 is attached integrally to the housing portion 10.

[0039] A wedge mounting hole 23 is formed on the opposite side of the wedge holder portion 20 from the PC tendon insertion opening 22. In this embodiment, the size of the wedge mounting hole 23 is formed to a length capable of accommodating the wedge 30, and is about 40 mm in this embodiment. The wedge mounting hole 23 has a wedge fitting opening 23a and a tapered portion 23b that reduces in diameter from the wedge fitting opening 23a toward the PC tendon insertion opening 22. The tapered portion 23b is a portion into which the wedge 30 is fitted, and is provided on the inner wall surface of the wedge mounting hole 23. The inner wall shape of the tapered portion 23b approximately matches the outer shape of the wedge 30.

[0040] As described above, the male thread portion 24 of the wedge body holder part 20 is a portion that screws into the female thread portion 13b of the wedge body holder installation part 13, and is formed on the outer periphery of the wedge body holder part 20 other than the knob part 25. In this example, the male thread portion 24 of the wedge body holder part 20 is formed in a portion approximately 40 mm from the wedge fitting opening 23a side.

[0041] The wedge 30 of this embodiment is made of steel, and as shown in Fig. 5A, is composed of a PC tendon through-hole 33, a wedge connecting O-ring 34 (wedge connecting device), and an O-ring fixing groove 35. And, on the inside of these three divided bodies 30a, 30b, 30c, as shown in Fig. 5C, continuous blade-shaped portions 32 are formed at regular intervals in the direction perpendicular to the longitudinal direction. Further, the O-ring fixing groove 35 is formed on the outer periphery on the end side of the divided bodies 30a, 30b, 30c having the larger diameter. That is, as shown in FIG. 5B, the segments 30a, 30b, and 30c of this embodiment are formed by dividing the wedge body 30 into three in the circumferential direction, and the wedge body 30 is formed by abutting the circumferential end faces of the segments 30a, 30b, and 30c.

[0042] In this manner, the wedge body 30 is integrally assembled with the segments 30a, 30b, and 30c by the wedge body connecting O-ring 34. That is, as shown in Fig. 5C, the O-ring fixing groove 35 is formed on the outer peripheral surface of the enlarged diameter side of the segments 30a, 30b, and 30c, and is formed to match the shape of the wedge body connecting O-ring 34. The groove width is 3 mm, and the groove depth is 2 mm. As shown in FIG. 5A(a), the wedge 30 in the assembled state (whole) is formed into a cone shape with a reduced diameter, matching with the tapered portion 23b of the wedge holder portion 20 shown in FIG.

[0043] In addition, the O-ring 34 for connecting the wedge bodies is made of a resin such as rubber, and as shown in (b) of Figure 5A, when the PC tension member T is inserted, the segments 30a, 30b, and 30c expand, and the inner blade-shaped portion 32 bites into and holds the PC tension member T as the O-ring 34 for connecting the wedge bodies is tightened. In this embodiment, the length of the wedge body 30 in the longitudinal direction is 50 mm, and the outer diameter of the expanded portion is 29.8 mm.

[0044] 5A(b), after the three divided bodies 30a, 30b, 30c are integrated by the wedge body connecting O-ring 34 to form the wedge body 30, the wedge body 30 engages with the PC tendon T. Then, the blade-shaped portion 32 is tightly bitten into the PC tendon T by the tapered portion 23b of the wedge holder part 20 and is tightly fitted into the tapered portion 23b, so that the PC tendon T is firmly clamped by the blade-shaped portion 32 in the PC tendon through-hole 33.

[0045] As shown in Fig. 5A(a), the PC tendon through hole 33 is an insertion hole for the PC tendon T formed inside the wedge body 30. The size of the PC tendon through hole 33 is a length of 50 mm, and a hole diameter of 15 mm on the expanded diameter side and 12 mm on the reduced diameter side. As shown in Fig. 5B, the PC tendon T is inserted into the PC tendon through-hole 33 from the reduced diameter side of the wedge body 30, and the segments 30a, 30b, and 30c are separated at the wedge body connecting O-ring 34, and the diameter of the PC tendon through-hole 33 expands. As shown in Fig. 5A(b), the diameter of the PC tendon through-hole 33 expands, and gaps 36 are generated in the axial direction at the end faces of the three segments 30a, 30b, and 30c.

[0046] 5D, the wedge connecting O-ring 34 has a circular shape and matches the shape of the enlarged diameter portion of the wedge 30. The wedge connecting O-ring 34 has an outer diameter of 25 mm, an inner diameter of 20 mm, and a width of 2 mm. It is advisable to color-code the wedge connecting O-rings 34 by size in order to distinguish between O-rings 34 for connecting high-strength rebars with a diameter of 13 mm and O-rings 34 for connecting high-strength rebars with a diameter of 16 mm.

[0047] As shown in Fig. 6A, the setting jig 40 is made of steel and has a roughly U-shape as a whole, with a size of 140 mm in the longitudinal direction and 45 mm in the width direction. The setting jig 40 has a horseshoe-shaped space portion 41 as an insertion portion through which the PC tendon T can be inserted, a wedge pressing portion 42, and a connecting portion 43 (striking portion). The horseshoe-shaped space 41 in this embodiment is formed on one end side and the other end side (that is, both end sides) of the setting jig 40.

[0048] The horseshoe-shaped spaces 41 at both ends are notches formed in the center of the wedge pressing portions 42, and these horseshoe-shaped spaces 41 sandwich the PC tendon T and restrict the PC tendon T in the axial direction. As shown in FIG. 6B, when the setting jig 40 is attached to a predetermined position in the hollow portion 11 through the opening 12, the PC tendon T is restricted in the horseshoe-shaped space portion 41, and the PC tendon T is positioned linearly in the axial direction.

[0049] As shown in Figures 6A and 6B, the wedge pressing portion 42 is an approximately rectangular prism on both ends of the setting jig 40, and has the horseshoe-shaped space portion 41 described above, a pressing portion 42a, and a tapered portion 42b. The size of the wedge pressing portion 42 is 40 mm in the vertical direction and 40 mm in the horizontal direction, and the thickness is 17 mm on the upper end side and 10 mm on the lower end side.

[0050] The pressing portion 42 a is a surface that presses and fits the wedge body 30 when the wedge body 30 is fitted into the wedge body holder portion 20 by the setting jig 40 . The size of the pressing portion 42a is 20 mm in the vertical direction, 20 mm in the horizontal direction, and 17 mm in thickness.

[0051] The connecting portion 43 (hitting portion) connects the pressing portions 42a at both ends (i.e., is formed between one end and the other end of the setting jig 40) and is formed in a substantially rectangular prism shape. The size of the connecting portion 43 (hitting portion) is 140 mm in the longitudinal direction, 20 mm in the width direction, and 25 mm in the height direction. The connecting portion 43 (striking portion) is used when striking the setting jig 40 from above to press-fit the wedge body 30 when attaching the setting jig 40, and is also used as a handle portion (grip portion) when moving the setting jig 40.

[0052] Tapered portion 42b is formed in a tapered shape and is a surface that allows pressing portion 42a to be positioned between wedge bodies 30 in order to facilitate mounting of wedge body 30 in a position for press-fitting. Tapered portion 42b is 20 mm in the vertical direction and 20 mm in the horizontal direction, and is 17 mm thick on the upper end side and 10 mm thick on the lower end side.

[0053] Although not shown, in order to prevent the housing unit 10 from tipping over when the housing unit 10 is placed on a horizontal location such as the ground, a housing tipping prevention unit 60 can be provided on the outer circumferential surface of the lower part of the housing unit 10. The shape of the housing tipping prevention unit 60 can be a semi-cylindrical or rectangular prism shape, but is not limited thereto.

[0054] For the PC tendon T, for example, a high-strength rebar (e.g., MK785) with a yield point of 590 to 1275 N / mm2 is used, and the diameter of the high-strength rebar is preferably 13 mm or 16 mm. In order to distinguish whether the diameter of the high-strength rebar is 13 mm or 16 mm, it is desirable to mark it according to its size.

[0055] As shown in Figures 8A and 8B, the method of using a connector 1 for a PC tendon T when manufacturing a PC member is such that a reaction body 70 is disposed at both ends of a specified section, and a jack 80 is installed on one of the reaction bodies 70. The PC tendon T is stretched across the reaction bodies 70 and fixed to the tensioning side reaction body 70 equipped with a jack 80 and the reaction body 70 on the reaction force receiving side.

[0056] The number of jacks 80 provided corresponds to the number of PC tendons T that are stretched between the reaction bodies 70. Between the reaction bodies 70 at both ends, formwork 90 for manufacturing the PC members is provided according to the number of PC members to be manufactured, and the formwork 90 has PC tendon insertion holes. In this case, a predetermined number of connectors 1 for the PC tendons T are provided at predetermined positions outside the formwork 90 of the PC member according to the length of the PC tendons T. Then, the opposing ends of the PC tendons T are connected to the connectors 1 for the PC tendons T, and the PC tendons T are connected in the axial direction.

[0057] Next, the method of using the connector 1 of the PC tendon T having the above-mentioned configuration will be explained using Figures 7A(a)-(d), 7B(e)-(h), 7C(i)-(k), 7D(l)-(m), 9A(a)-(d), 9B(e)-(h), and 9C(i)-(l). In this example, the connector 1 of the PC tendon T that connects opposing PC tendons T will be explained.

[0058] First, the assembly of the connector 1 of the PC tendon T will be described. As shown in Fig. 7A(a), the assembly method is to screw the wedge holder parts 20 into the wedge holder installation parts 13 from both end sides of the housing part 10. Then, as shown in Fig. 7A(b), the PC tendon T is inserted into the PC tendon insertion hole 21 from one side. Next, as shown in Figures 7A(c)-(e), the wedge body 30 is attached to the inserted PC tendon T from the opening 12 side (Figures 7B(c) and (d)). At this time, the wedge body 30 and the PC tendon T are in an assembled state as shown in Figure 5A(b). Then, after the wedge body 30 is placed in a predetermined position on the PC tendon T (Figure 7B(e)), the PC tendon T is pulled towards the PC tendon insertion hole 21 and inserted into the wedge attachment hole 23.

[0059] As shown in Figure 7B(g) to Figure 7C(j), the PC tendon T is inserted from the other side into the PC tendon insertion hole 21. At this time, as shown in Figure 7C(j), the PC tendon T is inserted into the wedge mounting hole 23 on the same axis. Next, the setting jig 40 is placed from the opening 12 into the hollow portion 11. At this time, the pressing portion 42a is positioned between the wedges 30, and the tapered portion 42b enters between the wedges 30 first, pressing the wedges 30, so that the pressing portion 42a can press the wedges 30. Then, when the setting jig 40 is inserted, the upper portion of the connecting portion 43 (striking portion) is struck with a hammer or the like to press and fit the wedges 30 (FIG. 7D(l)(m)).

[0060] After the connector 1 of the PC tendon T is used to span the PC tendon T between the reaction bodies 70, a tension force is introduced into the PC tendon T from the reaction body 70 side on the tensioning side using a jack 80, and the PC tendon T is tensioned. After tension is introduced into the PC tendon T, concrete is poured into the formwork 90, and when the concrete reaches a predetermined strength, the formwork 90 is removed and the tension is released.

[0061] The method of removing the connector 1 of the PC tendon T is as shown in Figures 9A(a)-(d), 9B(e)-(h), and 9C(i)-(l), in which first, the PC tendon T is cut on the outside of one end side and the other end side of the casing part 10, and then the setting jig 40 is removed from the opening 12 (Figure 9A(c)).

[0062] Next, since the wedge body 30 is tightly fitted into the tapered portion 23b and it is difficult to remove the wedge body 30 from the tapered portion 23b, a striking force is applied with a hammer or the like to the end of the other PC tendon T that has been cut on the outside of the other end side (FIGS. 9A(d) to 9B(g)). The wedge body 30 on the other end side that has the other PC tendon T fitted into it is removed from the tapered portion 23b.

[0063] Next, because the blade portion 32 of the wedge body 30 is bitten into the PC tendon T, the wedge body 30 is disassembled into three segments 30a, 30b, and 30c by removing the wedge body connecting O-ring 34, and then removed from the other PC tendon T and the three segments 31a, 31b, and 31c are removed from the opening 12. Next, the other PC tendon T is pulled out from the PC tendon insertion port 22 on the other end side. Then, an impact force is applied to the end of one of the PC tendons T that has been cut on the outside of one end side, and the wedge body 30 on the one end side into which one of the PC tendons T is fitted is removed from the tapered portion 23b (Figures 9B(h) to 9C(l)).

[0064] Next, the wedge body 30 has the wedge body connecting O-ring 34 removed, and is disassembled into three segments 30a, 30b, and 30c, which are then removed from one of the PC tendons T and removed as the three segments 31a, 31b, and 31c from the opening 12. Next, one of the PC tendons T is pulled out from the PC tendon insertion port 22 on one end side. Then, the housing portion 10, the wedge holder portion 20, the wedge 30, the setting jig 40, etc., which constitute the connection device 1 of the PC tendon T, are cleaned to remove dirt, and oil is applied thereto.

[0065] <Another embodiment of the connector 1 for PC tendon T> Next, a second embodiment of the connector 1 for PC tendon T will be described with reference to Fig. 10 to Fig. 13. This embodiment shows an example in which a housing part 10 constituting a connector 101 for a PC tendon is configured with a wedge holder part 20 on one end side and a screw-fitting holder part 120 on the other end side. In the following description, the same reference numerals will be used to designate the same parts as those in the above-described embodiment, and the description thereof will be omitted.

[0066] As shown in FIG. 10, the connector 101 for the PC tendon is mainly composed of a housing portion 10, a wedge holder portion 20, a screw-fitting holder portion 120, a wedge 30, and a setting jig 40. 10 and 11, the screw-on holder part 120 is screwed to the screw-on holder installation part 113 on the end (other end) opposite to the wedge holder part 20 formed at one end of the housing part 10. The screw-on holder part 120 is attached integrally with the housing part 10, and unlike the above embodiment, is configured to fasten a threaded reinforcing bar or the like having a threaded outer peripheral surface of a reinforcing bar material.

[0067] More specifically, the threaded holder part 120 is formed with a threaded rebar insertion hole 121, a male thread part 24, and a knob part 25. Threaded rebar insertion openings 122 are formed on both end sides of the threaded holder part 120, and the threaded rebar insertion hole 121 passes through the threaded holder part 120 in the longitudinal direction. The size of the threaded rebar insertion hole 121 is determined according to the thickness of the threaded rebar material 100T.

[0068] The threaded reinforcing bar insertion hole 121 is a portion into which the threaded reinforcing bar material 100T is screwed, and a female thread portion 121a is screwed into the inner wall surface of the threaded reinforcing bar insertion hole 121. The size of this female thread portion 121a is formed to match the male thread portion 100Ta of the threaded reinforcing bar material 100T. 11, the male thread portion 100Ta of the threaded reinforcing bar 100T is screwed into the female thread portion 121a of the screw-fitting holder portion 120. As shown in FIG.

[0069] 12, the wedge pressing portion 42 is formed on one end of the setting jig 40, and the pressing portion 42a formed on the other end serves as a surface formed for contacting the end of the threaded reinforcing bar 100T. The pressing portion 42a on the threaded reinforcing bar 100T side of the setting jig 40 contacts the end of the threaded reinforcing bar 100T. Since the threaded reinforcing bar 100T is threaded into the threaded holder portion 120, the longitudinal position of the threaded reinforcing bar 100T does not change even when the setting jig 40 is attached. The threaded reinforcing bar 100T and the pressing portion 42a on the other end side become the contact surfaces for pressing and fitting the wedge body 30 on the one end side.

[0070] Further, the tapered portion 42b on the side of the threaded reinforcing bar 100T is a surface formed to facilitate mounting the pressing portion 42a at the position of the above-mentioned contact surface.

[0071] The connecting portion 43 (striking portion) is used to strike the setting jig 40 from above when mounting the setting jig 40, and to mount the pressing portion 42a at the position of the contact surface described above.

[0072] Next, as shown in Figure 13, the method of using the connector 101 of the threaded reinforcing bar material 100T is to provide it as a connector 101 of the threaded reinforcing bar material 100T between the reaction bodies 70 arranged on both sides of a specified section, at a position close to the reaction body 70 outside the formwork 90 for manufacturing the PC member closest to the reaction body 70, and at a specified position between the formwork 90 and the reaction body 70. The threaded reinforcing bar 100T is connected to the threaded holder portion 120 on the reaction body 70 side of the connector 101 of the threaded reinforcing bar 100T, and the PC tendon T is connected to the wedge holder portion 20 on the formwork 90 side of the connector 101 of the threaded reinforcing bar 100T. The threaded reinforcing bar 100T and the PC tendon T are connected in the axial direction.

[0073] Furthermore, the threaded reinforcing bar material 100T may be a threaded reinforcing bar, a high-tensile deformed reinforcing bar (threaded reinforcing bar), or the like, but is not limited thereto, and any appropriate threaded reinforcing bar material 100T may be used.

[0074] As shown in FIG. 13, the threaded reinforcing bar 100T and the reaction body 70 are fixed to the outside of the reaction body 70 using a fixing nut 70a and a fixing plate 70b that correspond to the thickness of the threaded reinforcing bar 100T.

[0075] The fixing method between the screw reinforcing bar material 100T and the reaction body 70 is not limited to the fixing method using the fixing nut 70a and the fixing plate 70b, and other appropriate fixing methods are possible, such as a fixing method using a wedge fitting.

[0076] Next, the assembly of the connector 101 of the threaded reinforcing bar material 100T will be described. The connector 101 of the threaded reinforcing bar 100T is provided between the reaction body 70 and the formwork 90 that is closest to the reaction body 70. The threaded reinforcing bar 100T is connected to the reaction body 70 side of the connector 101 of the threaded reinforcing bar 100T, and the PC tendon T is connected to the formwork 90 side of the connector 101 of the threaded reinforcing bar 100T.

[0077] First, the threaded reinforcing bar material 100T is rotated and inserted from the threaded reinforcing bar insertion opening 122 on the end side of the housing part 10, and is screwed into the female threaded portion 121a of the threaded reinforcing bar insertion hole 121.

[0078] Next, the setting jig 40 is placed into the hollow portion 11 through the opening 12. At this time, the tapered portion 42b on the end side enters before the pressing portion 42a, and the pressing portion 42a on the end side becomes an abutment surface for pressing and fitting the wedge body 30 on the opposite end side.

[0079] The connecting portion 43 (striking portion) of the setting jig 40 strikes the setting jig 40 from above when mounting the setting jig 40, and is used when the pressing portion 42a mounts the setting jig at the position of the contact surface described above.

[0080] The threaded reinforcing bar 100T and the reaction body 70 are fixed to the outside of the reaction body 70 using a fixing nut 70a and a fixing plate 70b that correspond to the thickness of the threaded reinforcing bar 100T. Then, a tension is introduced to the threaded reinforcing bar 100T and the PC tendon T using a jack 80 from the reaction body 70 side on the tension side, and the threaded reinforcing bar 100T and the PC tendon T are tensioned.

[0081] Next, a method for removing the connector 101 of the threaded reinforcing bar material 100T will be described. First, the PC tendon T is cut on the outside of one end side of the casing portion 10, and the setting jig 40 is removed from the opening 12. Thereafter, the fixing nuts 70a and the fixing plates 70b of the threaded reinforcing bars 100T disposed on the outside of the reaction body 70 are removed.

[0082] Thereafter, the threaded reinforcing bar 100T that has been threaded into the threaded holder portion 120 of the housing portion 10 is rotated and removed from the threaded holder portion 120. Then, the threaded reinforcing bar 100T is pulled out to the outside of the reaction body 70 through the through hole 70c of the threaded reinforcing bar 100T formed in the approximate center of the reaction body 70 in the height direction.

[0083] Other embodiments In the above embodiment, the case where the housing 10 is cylindrical has been described, but the shape of the housing 10 is not limited to a cylindrical shape, and any shape such as a prismatic shape is possible.

[0084] In addition, in the above embodiment, a high-strength reinforcing bar with a specific diameter is used as the PC tendon T, but it is possible to select a diameter that matches the outer diameter of the casing portion 10.

[0085] In addition, in the above embodiment, the shape of the opening 12 is described as being approximately rectangular, but the shape of the opening 12 is not limited to being approximately rectangular, and any shape, such as approximately oval, is possible as long as it exposes the hollow portion 11 and allows the wedge body 30 and the PC tendon T to engage with each other while being visually observed.

[0086] In addition, in the above embodiment, a case has been described in which the wedge holder part 20 and the housing part 10 are screwed together, but the connection between the wedge holder part 20 and the housing part 10 is not limited to a screwed connection, and fitting means or other appropriate connection structures are possible.

[0087] In addition, in the above embodiment, a case has been described in which the wedge body 30 is composed of three divided bodies 30a, 30b, and 30c, but this is not limited to this, and the wedge body 30 can be composed of multiple divided bodies, such as two divided bodies.

[0088] In addition, in the above embodiment, the shape of the connecting portion 43 (impact portion) of the setting jig 40 is described as being approximately rectangular, but the shape of the connecting portion 43 (impact portion) can be any suitable shape, such as a cylindrical shape.

[0089] In addition, in the above embodiment, the use of high-strength steel bars as the PC tendons T was described, but it is possible to use any appropriate PC tendons T such as threaded steel bars, high-tensile deformed steel bars (threaded steel bars), high-tensile steel, PC twisted wire, etc. as the PC tendons T. [Explanation of symbols]

[0090] 1 Connector 10 Housing 11 Hollow part 12 Opening 13 Wedge holder installation section 13b Female thread 20 Wedge holder part 21 PC tendon insertion hole 22 PC tendon insertion hole 23 Wedge mounting hole 23a Wedge fitting entrance 23b Tapered section 24 Male thread 25 Knob 30 cuneiform 30a 30b 30c Split body 32 Blade section 33 PC tension material through hole 34 O-ring 35 O-ring fixing groove 36 Gap 40 sets of fixtures 41 Horseshoe-shaped space 42 Wedge pressing part 42a Pressing part 42b Tapered section 43 Connection part (striking part) 50 Wedge placement table 50a Wedge body insertion groove 50b Set jig installation surface 60 Housing tip-over prevention part 70 Reaction Body 70a Fixing nut 70b Fixed plate 70c through hole 80 Jack 90 Formwork 100T Screw Reinforcement Bar 100Ta male thread 101 Connector 113 Screw-fit holder installation part 120 Threaded holder part 121 Threaded rebar insertion hole 121a Female thread 122 Screw rebar insertion hole T PC tendons

Claims

1. A connector for PC tendons for connecting PC tendons, The connector is composed of a housing part having a hollow part constituting a main body, a wedge holder part for holding a wedge on at least one of one end side and the other end side of the housing part, the wedge that is disposed on the wedge holder part and holds the PC tendon, and a setting jig for pressing the wedge, the housing portion includes the hollow portion communicating with the wedge holder portion, an opening formed in a part of the hollow portion and open to the atmosphere, and a wedge holder installation portion to which the wedge holder portion is attached; The setting jig includes a pressing portion formed on at least one end side of both ends, a placement portion in which the PC tendon can be placed in the pressing portion, and a connecting portion connecting the pressing portions, This is a PC tension member connector characterized in that, when the setting jig is placed through the opening of the housing portion, the PC tension member is positioned and attached to the placement portion of the setting jig, and the wedge can be pressed against the wedge holder portion by the pressing portion of the setting jig while holding the PC tension member.

2. The PC tendon connector according to claim 1, characterized in that the PC tendon is arranged with its axial direction aligned at one end side and the other end side of the housing portion.

3. A PC tension member connector as described in claim 1 or 2, characterized in that the wedge holder portion comprises a PC tension member insertion hole provided on one end side of the wedge holder portion, a wedge mounting hole provided on the other end side of the wedge holder portion, a knob portion formed on the PC tension member insertion hole side, and a male thread portion formed on the outer periphery continuous with the knob portion.

4. A PC tension member connector as described in any one of claims 1 to 3, characterized in that the wedge body comprises a plurality of segments divided circumferentially, a blade-shaped portion formed on the inner surface of the segments, a PC tension member through hole formed by the plurality of segments through which the PC tension member is inserted, and a wedge body connector that integrates the segments.

5. A connector for PC tendons according to any one of claims 1 to 4, characterized in that the pressing portion of the setting jig is provided with a placement portion in which the PC tendons can be placed.

6. The PC tendon connector according to claim 5, characterized in that the pressing portion is tapered from the wedge pressing surface toward the free end side of the connecting portion.

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