How to connect grout injection jig and PCa member

Abstract

To provide a grout injection tool and a connection method of a PCa member that can efficiently and securely fill grout relative to every space where grout is filled.SOLUTION: A grout injection tool 50 is applied when a reinforcing-bar 65 is inserted to a sheath pipe 63 with which a precast-concrete-made PCa member 60 is provided, the grout injection tool is positioned to an end surface opening 63a of the sheath pipe 63 facing an end surface 61 of the PCa member 60, and grout is injected to the sheath pipe 63. The grout injection tool has a jig body 30 provided with a first end surface 32 abutting on the end surface opening 63a and a second end surface 33 located at an opposite side of the first end surface 32. The jig body 30 comprises an open hole 31 extending between a first end surface 32 and a second end surface 33, through which the reinforcing-bar 65 is penetrated, an injection hole 13 communicating with the open hole 31, in which grout is injected, and a slit 12 communicating with the injection hole 13 and extending along the open hole 31 between an intersecting position with the injection hole 13 and the first end surface 32.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for connecting a grout injection jig to a PCa member. [Background technology]

[0002] For example, when constructing a column-beam joint in a reinforced concrete (RC) structure by pouring concrete on-site, the construction period can be lengthy, a problem that becomes even more pronounced in the case of high-rise buildings. Therefore, a construction method may be adopted in which the upper and lower columns, the joints connecting the columns, and the beams on either side of the joints are all made of precast concrete (hereinafter referred to as "PCa"), the PCa columns, PCa joints, and PCa beams (all of which are included in PCa components) are transported to the site, and after the PCa columns and PCa joints are assembled, PCa beams are temporarily installed on either side of the PCa joint. The rebar that protrudes laterally from the end face of one of the PCa beams is inserted into the sheath pipe provided in the PCa joint, protruding to the other side of the PCa joint, and the rebar is fitted into a mechanical joint inside the other PCa beam, thereby connecting the PCa joint to the left and right PCa beams.

[0003] This connection method then requires the injection of grout into the sheath pipe of the PCa joint and into the mechanical joints inside the PCa beams that connect the rebars to each other, thereby connecting the rebars to the sheath pipes and mechanical joints. Therefore, a method is used in which grout injection holes are provided in the mechanical joints, and the grout injected through the injection holes fills the interconnected spaces. Specifically, the grout filled inside the mechanical joints flows into the vertical joint space at the interface between the PCa beam equipped with the mechanical joint and the PCa joint, then flows through the sheath pipe of the PCa joint, and finally flows into the vertical joint space between the PCa joint and the other PCa beam. The other PCa beam is provided with a discharge hole connected to the vertical joint space. By confirming that the grout flowing into the vertical joint space is discharged from the discharge hole, it is possible to determine whether each space has been filled with grout.

[0004] However, even if it is possible to confirm that the grout injected from the injection hole passes through various filled spaces and is discharged from a discharge hole located away from the injection hole, it is not necessarily guaranteed that all of the mutually communicating filled spaces are densely filled with grout. It is quite possible that some filled spaces will not be filled with grout due to some influence, or that the grout will flow to the discharge hole and be discharged in a state where it is not filled sufficiently.

[0005] In view of the above, when connecting one PCa member equipped with a sheath tube to another PCa member having reinforcing bars protruding from its end face, a method of connecting the grout injection jig and the PCa member is desired that can efficiently and reliably fill all of the spaces to be filled with grout.

[0006] Patent Document 1 proposes a precast beam member and a beam construction method therefor. The precast beam member has multiple shear reinforcement bars embedded at intervals in precast concrete, and multiple parallel sheath pipes embedded in each precast concrete for inserting the lower beam main reinforcement bars between the lower ends of two precast concrete pieces. Splice reinforcement is arranged in the center of the sheath pipes, forming a lap splice formation area. The beam construction method for precast beam members involves inserting the lower beam main reinforcement bars through the sheath pipes of the beam members and installing them sequentially between the tops of the columns. The lower beam main reinforcement bars are then moved and adjusted to pass them between the end faces of the precast beam members above the column tops to form reinforcement. The front and rear ends of each lower beam main reinforcement are then connected within the lap splice formation area. Concrete is then poured between the end faces of the precast beam members, and grout is filled into each sheath pipe to construct the precast beam member. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 5-247999 Summary of the Invention [Problem to be solved by the invention]

[0008] The beam construction method for precast beam members described in Patent Document 1 merely describes that the beam is constructed by filling grout material into the sheath tube, but does not disclose any means or method for reliably filling grout into all of the spaces to be filled with grout.

[0009] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a method for connecting a grout injection jig to a PCa member, which can efficiently and reliably fill grout into all of the filled spaces when connecting one PCa member equipped with a sheath tube to another PCa member having reinforcing bars protruding from its end face. [Means for solving the problem]

[0010] In order to achieve the above object, one aspect of the grout injection jig according to the present invention is: A grout injection jig is used when a reinforcing bar is inserted into a sheath pipe provided in a precast concrete PCa member, and the reinforcing bar is aligned with the end face opening of the sheath pipe facing the end face of the PCa member and grout is injected into the sheath pipe, The grout injection jig has a jig body including a first end surface abutting the end surface opening and a second end surface opposite to the first end surface; The jig body is a through hole extending between the first end surface and the second end surface and through which the reinforcing bar passes; an injection hole communicating with the through hole and into which the grout is injected; The through hole is characterized by comprising a slit that communicates with the injection hole and extends along the through hole between a position that intersects with the injection hole and the first end surface.

[0011] According to this aspect, the jig body includes a through hole extending between a first end face abutting the end-face opening of the sheath tube of the PCa member and a second end face on the opposite side, through which a rebar is passed, and an injection hole communicating with the through hole and through which grout is injected. The jig body further includes a slit communicating with the injection hole and extending along the through hole between a position intersecting the injection hole and the first end face. This allows grout injected into the injection hole to be guided into the sheath tube through the slit, enabling the sheath tube to be efficiently and reliably filled with grout. Examples of PCa members that include a sheath tube include PCa joints and PCa beams. The slit may extend parallel to the through hole at a distance from the through hole, or may protrude laterally from the through hole (so as to be in communication with the through hole).

[0012] In another aspect of the grout injection jig according to the present invention, the jig body includes a plurality of divided bodies that divide the through hole, The divided main bodies are arranged so as to form the through-hole, and the divided main bodies are fastened together around their peripheries by a fastening band.

[0013] According to this aspect, since the jig body is formed of multiple split bodies that divide the through hole, for example, after inserting a reinforcing bar into the sheath tube of the PCa member, the multiple split bodies can be mutually arranged so as to sandwich the reinforcing bar protruding from the end opening of the sheath tube, thereby improving the attachability of the grout injection jig. Here, the multiple split bodies are typically two half-shaped split bodies, but three or more split bodies may also be used.

[0014] In another aspect of the grout injection jig according to the present invention, The first end surface of the jig body is characterized in that a spacer is provided which extends into the inside of the sheath tube to support the reinforcing bar from below and align the reinforcing bar inside the sheath tube.

[0015] According to this aspect, a spacer that extends into the sheath tube and supports the reinforcing bar is provided on the first end face of the jig body. Therefore, when the grout injection jig is installed, the reinforcing bar inserted into the sheath tube can be lifted by the spacer and aligned to, for example, the center position of the sheath tube, thereby achieving both efficient installation of the spacer and uniform and dense filling of grout between the reinforcing bar and the inner surface of the sheath tube.

[0016] Another aspect of the grout injection jig according to the present invention is At least the jig body is made of hard resin.

[0017] According to this embodiment, the jig body is formed from a hard resin, which ensures sufficient hardness to withstand the grout injection pressure, etc., while being lightweight and easy to handle, and there is no risk of rusting like with metal fittings, etc., allowing for multiple uses.

[0018] In addition, one aspect of the PCa member connection method according to the present invention is as follows: A grout injection jig having a jig body with a first end surface and a second end surface opposite the first end surface, The jig body is a through hole extending between the first end surface and the second end surface and through which a reinforcing bar is passed; An injection hole communicating with the through hole and into which grout is injected; A step A1 of preparing a grout injection jig, the grout injection jig having a slit communicating with the injection hole and extending along the through hole between a position intersecting the injection hole and the first end surface; B1 process: passing a first reinforcing bar through a sheath pipe provided in a first PCa member made of precast concrete, causing the first reinforcing bar to protrude from both a third end face opening where the sheath pipe faces the third end face of the first PCa member and a fourth end face opening where the sheath pipe faces the fourth end face of the first PCa member, inserting the first reinforcing bar into the through hole and temporarily installing the grout injection jig, connecting one end of a second reinforcing bar provided in a second PCa member and one end of the first reinforcing bar via a mechanical joint, and finally installing the grout injection jig at the position of the third end face opening; A C1 step of installing the backer material or the separate grout injection jig at the position of the fourth end surface opening while passing the first reinforcing bar protruding from the fourth end surface opening through a through hole provided in the backer material or the through hole of the separate grout injection jig; Step D: Injecting grout from the injection hole of one of the grout injection jigs, and confirming that the grout that has flowed through the slit and the inside of the sheath tube has been discharged from the slit provided in the backer material or the injection hole of the other grout injection jig, thereby completing the grout injection; The method is characterized by having a step E of pouring concrete between the first PCa member and the second PCa member so as to bury a portion of the first reinforcing bar, the mechanical joint, and a portion of the second reinforcing bar, thereby connecting the first PCa member and the second PCa member.

[0019] According to this aspect, by using the grout injection jig of the present invention to inject grout into the inside of the sheath tube of the first PCa member through which the first reinforcing bar is inserted, the inside of the sheath tube can be filled with grout efficiently and reliably.

[0020] In addition, by confirming that grout has been ejected from the slit in the backer material installed at the other opening of the sheath tube of the first PCa member or from the injection hole of a separate grout injection jig, it is possible to ensure that grout has been injected accurately inside the sheath tube.

[0021] After filling the sheath tube of the first PCa member with grout, the grout injection jig and backing material installed at the end opening of the sheath tube are removed. Next, one end of the first rebar inserted and fixed through the sheath tube of the first PCa member is connected to one end of the second rebar of the other, second PCa member using a mechanical joint, and the interior of this mechanical joint is also filled with grout or epoxy resin. Because the mechanical joint is a relatively short and small component, there is no need to use a grout injection jig when filling the interior of the mechanical joint with grout, and the grout can be directly injected through the gap at the end opening of the mechanical joint where the first and second rebars are connected. After the injection of grout, epoxy resin, etc. into the inside of the sheath tube and the inside of the mechanical joint is completed, concrete is poured into the space between the first PCa member and the second PCa member so as to bury part of the first reinforcing bar, the mechanical joint, and part of the second reinforcing bar, and the PCa members are connected by connecting the first PCa member and the second PCa member.

[0022] For example, the first PCa member may be a PCa joint and the second PCa member may be a PCa beam. In this case, a first reinforcing bar inserted into the sheath pipe of the PCa joint is extended to the left and right of the PCa joint, and one end of a second reinforcing bar provided on the PCa beams arranged on the left and right is connected to the left and right ends of the first reinforcing bar with a mechanical joint, respectively. By pouring concrete on the left and right of the PCa joint, a column-beam joint that is T-shaped when viewed from the front is formed, with the PCa beam extending to the left and right sides of the PCa joint assembled above the PCa column.

[0023] Another aspect of the PCa member connection method according to the present invention is: A grout injection jig having a jig body with a first end surface and a second end surface opposite the first end surface, The jig body is a through hole extending between the first end surface and the second end surface and through which a reinforcing bar is passed; An injection hole communicating with the through hole and into which grout is injected; a slit communicating with the injection hole and extending along the through hole between a position intersecting the injection hole and the first end surface, A2 step of preparing a grout injection jig, wherein the jig body is formed by a plurality of divided bodies that divide the through hole; B2 process includes passing a first reinforcing bar through a sheath tube provided in a first PCa member made of precast concrete, causing the first reinforcing bar to protrude from both a third end face opening where the sheath tube faces the third end face of the first PCa member and a fourth end face opening where the sheath tube faces the fourth end face of the first PCa member, connecting one end of a second reinforcing bar provided in a second PCa member to one end of the first reinforcing bar via a mechanical joint, arranging a plurality of the divided bodies at the position of the third end face opening while forming the through holes so as to sandwich the first reinforcing bar, and fastening the peripheries of the plurality of divided bodies with fastening bands to form and install the grout injection jig; A C2 step of installing the backer material or the separate grout injection jig at the position of the fourth end surface opening while passing the first reinforcing bar protruding from the fourth end surface opening through a through hole provided in the backer material or the through hole of the separate grout injection jig; Step D: Injecting grout from the injection hole of one of the grout injection jigs, and confirming that the grout that has flowed through the slit and the inside of the sheath tube has been discharged from the slit provided in the backer material or the injection hole of the other grout injection jig, thereby completing the grout injection; The method is characterized by having a step E of pouring concrete between the first PCa member and the second PCa member so as to bury a portion of the first reinforcing bar, the mechanical joint, and a portion of the second reinforcing bar, thereby connecting the first PCa member and the second PCa member.

[0024] According to this aspect, the use of a grout injection jig formed by a split body improves the ease of attachment and detachment of the grout injection jig. Therefore, for example, a first rebar is inserted into the sheath tube of a first PCa member, and grout injection jigs for grout injection and grout discharge (discharge) are installed at the left and right end openings of the sheath tube. Furthermore, before grout injection, the first rebar and a second rebar of a second PCa member are connected via a mechanical joint. Then, grout can be injected into the sheath tube and grout, epoxy resin, or the like can be injected into the mechanical joint. After grout injection, the grout injection jig can be dismantled and removed while separating the split body, allowing for the next step of pouring concrete between the first PCa member and the second PCa member.

[0025] In another embodiment of the PCa member connection method according to the present invention, In the step B1 or the step B2, spacers are installed at least near the third end surface opening and near the fourth end surface opening in a lower portion of the inside of the sheath tube; The first reinforcing bar is supported from below by at least two of the spacers, and the first reinforcing bar is aligned inside the sheath tube.

[0026] According to this aspect, by installing at least two spacers inside the sheath tube to support the first rebar from below and aligning the first rebar inside the sheath tube, an annular space of as uniform width as possible can be formed inside the sheath tube between the first rebar and the inner surface of the sheath tube, and grout can be filled in, thereby achieving a strong connection between the first rebar and the sheath tube.

[0027] In another embodiment of the PCa member connection method according to the present invention, In the A1 step or the A2 step, a spacer is provided on the first end surface of the jig body, the spacer extending into the sheath tube supports the reinforcing bar from below, and the spacer aligns the reinforcing bar inside the sheath tube; In steps B1, B2, C1, and C2, when the two grout injection jigs are installed at the positions of the third end face opening and the fourth end face opening, respectively, the spacer is inserted into the inside of the sheath tube to support the first reinforcing bar from below.

[0028] According to this aspect, the grout injection jig is equipped with a spacer that supports the first rebar inserted into the sheath tube from below, so that when the grout injection jig is installed at the end opening of the sheath tube, the spacer enters the sheath tube and automatically lifts and supports the first rebar, thereby enabling the spacer to be installed efficiently in the sheath tube. [Effects of the Invention]

[0029] As can be understood from the above explanation, according to the method of connecting a grout injection jig and a PCa member of the present invention, when connecting one PCa member equipped with a sheath tube to another PCa member having reinforcing bars protruding from its end face, grout can be efficiently and reliably filled into all of the filled spaces into which grout is to be filled. [Brief explanation of the drawings]

[0030] [Figure 1] FIG. 2 is a perspective view of an example of a grout injection jig according to the first embodiment. [Figure 2A] FIG. 2 is a view taken along the line IIa-IIa in FIG. [Figure 2B] FIG. 2 is a view taken along the line IIb-IIb in FIG. [Figure 2C] FIG. 2 is a view taken along the line IIc-IIc in FIG. [Figure 3] FIG. 10 is a perspective view of an example of a grout injection jig according to a second embodiment. [Figure 4] 1 is a process diagram of an example of a method for connecting PCa members according to an embodiment. [Figure 5] 4A to 4C are process diagrams illustrating an example of a method for connecting PCa members according to an embodiment. [Figure 6]5A to 5C are process diagrams illustrating an example of a method for connecting PCa members according to an embodiment. [Figure 7] 6A to 6C are process diagrams illustrating an example of a method for connecting PCa members according to an embodiment. [Figure 8] 7A to 7C are process diagrams illustrating an example of a method for connecting PCa members according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0031] Hereinafter, an example of a grout injection jig according to each embodiment and an example of a PCa member connection method according to each embodiment will be described with reference to the accompanying drawings. Note that in this specification and the drawings, substantially identical components may be designated by the same reference numerals to avoid redundant description.

[0032] [Grout injection jig according to the first embodiment] First, an example of a grout injection jig according to the first embodiment will be described with reference to Figures 1 and 2. Here, Figure 1 is a perspective view of an example of the grout injection jig according to the first embodiment, and Figures 2A, 2B, and 2C are views taken along arrows IIa-IIa, IIb-IIb, and IIc-IIc in Figure 1, respectively.

[0033] As will be described in detail below, the grout injection jig 50 is a jig that is used when inserting reinforcing bars into a sheath pipe provided in a PCa member made of precast concrete, aligning the reinforcing bars with the end face opening of the sheath pipe facing the end face of the PCa member, and injecting grout into the sheath pipe.

[0034] The grout injection jig 50 has a cylindrical jig body 30 with a first end face 32 that abuts against the end face opening of the sheath tube and a second end face 33 on the opposite side of the first end face 32. The jig body 30 is formed from two separate bodies 10, 20. Here, the jig body may be an integrally molded body as a whole, but it is preferable to form the jig body from multiple (two in the illustrated example) separate bodies 10, 20 as in the illustrated example, as this improves the ease of attachment and removal of the grout injection jig 50 and increases construction efficiency. Furthermore, the external shape of the jig body may be a polygonal prism, including a rectangular parallelepiped, in addition to the cylindrical shape of the illustrated example.

[0035] Half-split through holes 11, 21 are provided at corresponding positions on the abutment surfaces of the two semi-cylindrical split bodies 10, 20, so that when the split bodies 10, 20 are abutted as shown in the example, a through hole 31 is formed.

[0036] The through hole 31 has a cross-sectional dimension that is the same as or approximately the same as the outer diameter of the first reinforcing bar to be inserted, and penetrates the jig body 30 between a first end face 32 and a second end face 33 in the X direction.

[0037] The jig body 30 is formed, for example, from a hard resin, and specific materials include polyethylene (PE), polypropylene (PP), polyvinylidene fluoride (PVDF), polyvinyl chloride (PVC), and hard rubber such as ethylene propylene diene rubber (EPDM).

[0038] By forming the jig body 30 from a hard resin, it is possible to ensure sufficient hardness to withstand the grout injection pressure, while also being lightweight and easy to handle, and there is no risk of rusting like with metal fittings, etc., allowing for multiple uses. The jig body may also be formed from a metal material that is resistant to rust, and for example, by using an aluminum jig body, a jig body with appropriate strength and light weight can be obtained.

[0039] One of the divided bodies 10 forming the jig body 30 is provided with an injection hole 13 which communicates with the half through-hole 11 forming the through-hole 31 and through which grout is injected.

[0040] Furthermore, divided body 10 is provided with slit 12 that communicates with casting hole 13 and extends along through hole 31 between the position where it intersects with casting hole 13 and first end face 32. In the illustrated example, slit 12 is in the form of a recess that protrudes entirely to the side of through hole 31, but in addition to the illustrated example, slit 12 may also be in the form of a recess that extends along through hole 31 at a position away from through hole 31.

[0041] With the above-described configuration, the vertical cross-sectional configuration of the jig body 30 perpendicular to the axial direction changes depending on the position in the axial direction, as shown in FIGS. 2A to 2C.

[0042] When grout injection jig 50 is actually used, two divided bodies 10, 20 are brought into contact with each other while forming through-hole 31 so as to sandwich the rebar inserted into the sheath pipe of the PCa member, and the jig is installed on the end face of the PCa member.After that, as shown in Figure 1, the two divided bodies 10, 20 are fastened around their peripheries with, for example, a plurality of fastening bands 40 (two in the illustrated example), thereby forming grout injection jig 50.In this case, injection hole 13, through which grout is injected, may be arranged to face upward, downward, or to the side, and the position of injection hole 13 is set taking into consideration workability.

[0043] By applying the grout injection jig 50, the grout injected into the injection hole 13 can be guided through the slit 12 into the sheath tube of the PCa member, making it possible to efficiently and reliably fill the sheath tube with grout.

[0044] [Grout injection jig according to the second embodiment] Next, an example of a grout injection jig according to a second embodiment will be described with reference to Fig. 3. Here, Fig. 3 is a perspective view of an example of a grout injection jig according to the second embodiment.

[0045] The grout injection jig 50A differs from the grout injection jig 50 shown in FIG. 1 in that a spacer 35 is provided below the opening of the through-hole 31 in the first end face 32 of the jig body 30.

[0046] The spacer 35 is molded integrally with the divided body 20, for example, but may also be molded separately and bonded to the first end surface 32.

[0047] According to the grout injection jig 50A, the spacer 35 that extends into the sheath tube and supports the rebar is provided on the first end face 32 of the jig body 30. Therefore, when the grout injection jig 50A is installed, the spacer 35 automatically lifts the rebar that has already been inserted into the sheath tube, and the rebar can be aligned, for example, at the center of the sheath tube. This allows for both efficient installation of the spacer 35 and uniform and dense filling of grout between the rebar and the inner surface of the sheath tube.

[0048] [Connection method for PCa members according to the embodiment] Next, an example of a method for connecting PCa members according to an embodiment will be described with reference to Figures 4 to 8. Figures 4 to 8 are, in order, process diagrams of an example of a method for connecting PCa members according to an embodiment. In the following explanation, a connection method using the grout injection jig 50A shown in Figure 3 will be described, but even in the case of using a grout injection jig whose jig body is an integrally molded member, differences in the method from when using the grout injection jig 50A will be mentioned as appropriate.

[0049] The following description will explain a method of connecting a PCa joint, which is a first PCa member 60 made of precast concrete, to two PCa beams, which are second PCa members 70 made of precast concrete on either side of it.

[0050] At the construction site, a PCa column 68 is erected, and a PCa joint 60 is installed at the top end of the PCa column 68. Although not shown, multiple mechanical joints are embedded, for example, below the PCa joint 60, and the main column reinforcement bars protruding upward from the top end surface of the PCa column 68 are fitted into the mechanical joints below the PCa joint. A horizontal joint (not shown) is formed between the PCa column 68 and the PCa joint 60 by injecting grout, and this grout penetrates into the mechanical joints, connecting the main column reinforcement bars to the mechanical joint. Although not shown, the PCa joint 60 has multiple joint reinforcement bars protruding upward from its top end surface, and the joint reinforcement bars are fitted into mechanical joints below the PCa column of the upper floor (not shown).

[0051] In the method for connecting PCa members, first, a required number of grout injection jigs 50A shown in FIG. 3 are prepared (step A2).

[0052] Here, when using a grout injection jig whose jig body is an integrally molded member, a required number of grout injection jigs 50 are similarly prepared (step A1).

[0053] Next, as shown in FIG. 4, first reinforcing bars 65 are inserted through each of the multiple sheath pipes 63 (two, one above the other, in the illustrated example) provided in the PCa joint 60.

[0054] In the illustrated example, the left end face of the PCa joint 60 is the third end face 61, and the right end face is the fourth end face 62. The sheath tube 63 extends horizontally between the third end face 61 and the fourth end face 62, and a third end opening 63a and a fourth end opening 63b are provided at positions facing each end face of the sheath tube 63. A first reinforcing bar 65 is temporarily installed in each sheath tube 63 with the first reinforcing bar 65 protruding from both the third end face opening 63a and the fourth end face opening 63b.

[0055] Next, as shown in Figure 5, the two divided bodies 10, 20 are arranged at the positions of the upper and lower third end face openings 63a, forming through holes 31 so as to sandwich the first reinforcing bar 65, and the two divided bodies 10, 20 are fastened around the periphery with fastening bands 40 to form and install the grout injection jig 50A.

[0056] When the grout injection jig 50A is installed, the spacer 35 protruding from the first end face 32 thereof is inserted downward into the sheath tube 63 in the Y1 direction.

[0057] By inserting this spacer 35 into the sheath tube 63, the first rebar 65 inserted in the sheath tube 63 is lifted upward in the Y2 direction, and the first rebar 65 supported by the spacer 35 is aligned with the cross-sectional center of the sheath tube 63. When the grout injection jig 50 shown in Fig. 1 is used, prior to installing the grout injection jig 50, a spacer is installed inside the sheath tube 63 to support the first rebar 65, and then the grout injection jig 50 is installed.

[0058] After installing the grout injection jig 50A, a lock nut 55 is fitted onto the first rebar 65, and the second end face 33 of the grout injection jig 50A is pressed with the lock nut 55, thereby installing the grout injection jig 50A so that it cannot be moved (this is step B2).

[0059] Here, when using a grout injection jig whose jig body is an integrally molded member, the end of the first reinforcing bar 65 is inserted into the through hole 31, while the grout injection jig 50 is moved to the third end face 61 of the PCa joint 60 and installed, and then the lock nut 55 is fitted to install the grout injection jig 50 (step B1).

[0060] After installing the grout injection jig 50A, as shown in Figure 5, the two split bodies 10, 20 are arranged at the positions of the upper and lower fourth end face openings 63b, forming through holes 31 so as to sandwich the first reinforcing bar 65, and the two split bodies 10, 20 are fastened around the periphery with fastening bands 40 to form and install the grout injection jig 50A.

[0061] Here, the grout injection jig 50A installed at the position of the fourth end face opening 63b (to the right of the PCa joint 60 in FIG. 5) is not used as a jig for injecting grout, but is used as a jig for confirming that the sheath tube 63 has been filled with grout. Therefore, in the grout injection jig 50A installed on the right side in FIG. 5, the injection hole 13 functions as a grout discharge hole (discharge hole).

[0062] The right-side grout injection jig 50A is also installed while the spacer 35 protruding from the first end face 32 thereof is inserted downward inside the sheath tube 63 in the Y3 direction.

[0063] By inserting this spacer 35 into the sheath tube 63, the first reinforcing bar 65 inserted into the sheath tube 63 is lifted upward in the Y4 direction, and the first reinforcing bar 65 supported by the spacer 35 is aligned with the center of the cross section of the sheath tube 63.

[0064] In this way, the spacers 35 at the left and right ends inside the sheath tube 63 position the first reinforcing bar 65 horizontally inside the sheath tube 63 and at the center of the cross section of the sheath tube 63.

[0065] After installing the right-side grout injection jig 50A, a lock nut 55 is fitted onto the first rebar 65 and the second end face 33 of the grout injection jig 50A is pressed with the lock nut 55, thereby installing the right-side grout injection jig 50A so that it cannot be moved (this is step C2).

[0066] Although not shown, a backer material with slits may be installed instead of the grout injection jig 50A on the right side used to check the grout filling.

[0067] Furthermore, when using a grout injection jig whose jig body is an integrally molded member to check grout filling, the end of the first reinforcing bar 65 is inserted into the through hole 31, while the grout injection jig 50 is moved to the third end face 61 of the PCa joint 60 and installed, and then the lock nut 55 is fitted to install the grout injection jig 50 (step C1).

[0068] After installing a grout injection jig 50A for grout injection and grout discharge on the third end face 61 and the fourth end face 62 of the PCa joint 60, respectively, the left and right ends of the first reinforcing bar 65 and the ends of the second reinforcing bars 75 protruding from the ends of the PCa beams 70 on the left and right are screwed into mechanical joints 72 such as couplers, thereby connecting the first reinforcing bar 65 and the second reinforcing bar 75 via the mechanical joints 72.

[0069] Next, as shown in Fig. 6, grout is injected in the Y5 direction from the injection hole 13 of the right-side grout injection jig 50A. The grout injected into the injection hole 13 is supplied into the inside of the sheath tube 63 through the slit 12 communicating with the injection hole 13.

[0070] Inside the sheath tube 63, the first rebar 65 is aligned with the cross-sectional center of the sheath tube 63 by the spacer 35, and therefore an annular gap of approximately uniform width is formed between the first rebar 65 and the inner surface of the sheath tube 63 along the longitudinal direction of the sheath tube 63. The grout supplied to the sheath tube 63 flows through this annular gap in the Y6 direction and enters the slit 12 of the grout injection jig 50A on the right side, and the grout that flows from the slit 12 into the injection hole 13 is discharged (discharged) to the outside in the Y7 direction.

[0071] By checking the discharge of this grout, the worker can determine that the inside of the sheath pipe 63 is densely filled with grout.

[0072] Following the filling of the sheath tube 63 with grout, grout, epoxy resin, or the like is also injected into the mechanical joint 72 connecting the first reinforcing bar 65 and the second reinforcing bar 75. For example, when injecting grout into the mechanical joint 72, the grout can be injected directly through the end opening of the mechanical joint 72 without using the grout injection jig 50A.

[0073] As shown in Figure 7, the inside of the sheath tube 63 is densely filled with grout G, and the inside of the left and right mechanical joints 72 is also filled with grout or epoxy resin. After that, the grout injection jig 50A is removed, and the concrete is formed in its pre-cast state at the site (this is process D).

[0074] Here, when using a grout injection jig whose jig body is an integrally molded member, after injecting grout into the sheath pipe 63, the grout injection jig 50 is pulled out from the end of the first reinforcing bar 65 and removed, and then the end of the first reinforcing bar 65 and the end of the second reinforcing bar 75 of the PCa beam 70 are screwed into the mechanical joint 72, and grout, epoxy resin, or the like is filled into the mechanical joint 72. In other words, by using the grout injection jig 50A having the divided bodies 10, 20, it is possible to vary the timing of removing the grout injection jig 50A, and it is possible to continuously fill the sheath pipe 63 and the mechanical joint 72 with grout, thereby improving construction efficiency.

[0075] Next, as shown in Figure 8, concrete is poured into the space between the PCa joint 60 and the left and right PCa beams 70 so as to bury part of the first reinforcing bar 65, the mechanical joint 72, and part of the second reinforcing bar 75, and by constructing, for example, a concrete connector 80 having the same cross-sectional shape and dimensions as the PCa beam 70, the PCa joint 60 and the PCa beam 70 are connected via the concrete connector 80, and a column-beam joint 100 is constructed.

[0076] According to the illustrated method of connecting PCa members, by using grout injection jigs 50, 50A when injecting grout into the sheath tube 63, the grout G can be efficiently and reliably filled into all of the filled spaces into which the grout G is to be filled, thereby realizing an efficient method of connecting PCa members.

[0077] The present invention is not limited to the configurations shown here, and other embodiments may be possible in which other components are combined with the configurations described in the above embodiments. In this regard, the present invention can be modified within the scope of the present invention, and can be appropriately determined depending on the application form. [Explanation of symbols]

[0078] 10,20: Split body 11, 21: Half-split through-hole 12:Slit 13: Injection hole 30: Jig body 31:Through hole 32: First end surface 33: Second end surface 35: Spacer 40: Fastening band 50, 50A: Grout injection jig 55: Lock nut 60: First PCa member (PCa joint, PCa member) 61: Third end face (end face) 62: 4th end face (end face) 63: Sheath tube 63a: Third end opening (end opening) 63b: 4th end opening (end opening) 65: First rebar (rebar) 68: PCa pillar 70: Second PCa member (PCa beam, PCa member) 72: Mechanical coupling 75: Second rebar (rebar) 80: Concrete connector 100: Column beam joint G: Grout

Claims

1. A grout injection jig is used when a reinforcing bar is inserted into a sheath pipe provided in a precast concrete PCa member, and the reinforcing bar is aligned with an end face opening of the sheath pipe facing the end face of the PCa member, and grout is injected into the sheath pipe. The grout injection jig has a jig body including a first end surface abutting the end surface opening and a second end surface opposite the first end surface; The jig body is a through hole extending between the first end surface and the second end surface and through which the reinforcing bar passes; an injection hole communicating with the through hole and into which the grout is injected; A grout injection jig comprising: a slit communicating with the injection hole and extending along the through hole between a position intersecting the injection hole and the first end face.

2. the jig body includes a plurality of divided bodies that divide the through hole, 2. The grout injection jig according to claim 1, wherein a plurality of the divided bodies are arranged so as to form the through-hole, and the peripheries of the plurality of divided bodies are fastened together with a fastening band.

3. 3. A grout injection jig as described in claim 1 or 2, characterized in that a spacer is provided on the first end surface of the jig body, extending into the inside of the sheath tube to support the reinforcing bar from below and align the reinforcing bar inside the sheath tube.

4. 4. The grout injection jig according to claim 1, wherein at least the jig body is made of a hard resin.

5. A grout injection tool having a tool body with a first end surface and a second end surface opposite the first end surface, The jig body is a through hole extending between the first end surface and the second end surface and through which a reinforcing bar is passed; An injection hole communicating with the through hole and into which grout is injected; A step A1 includes preparing a grout injection jig, the grout injection jig including a slit communicating with the injection hole and extending along the through hole between a position intersecting the injection hole and the first end surface; B1 process: passing a first reinforcing bar through a sheath tube provided in a first PCa member made of precast concrete, causing the first reinforcing bar to protrude from both a third end face opening where the sheath tube faces a third end face of the first PCa member and a fourth end face opening where the sheath tube faces a fourth end face of the first PCa member; inserting the first reinforcing bar into the through hole and temporarily installing the grout injection jig; connecting one end of a second reinforcing bar provided in a second PCa member and one end of the first reinforcing bar via a mechanical joint; and finally installing the grout injection jig at the position of the third end face opening; A C1 step of installing the backer material or the separate grout injection jig at the position of the fourth end surface opening while passing the first reinforcing bar protruding from the fourth end surface opening through a through hole provided in the backer material or the through hole of the separate grout injection jig; Step D: Injecting grout from the injection hole of one of the grout injection jigs, and confirming that the grout that has flowed through the slit and the inside of the sheath tube has been discharged from the slit provided in the backer material or the injection hole of the other grout injection jig, thereby completing the grout injection; A method for connecting PCa members, characterized by including a step E of pouring concrete between the first PCa member and the second PCa member so as to bury a portion of the first reinforcing bar, the mechanical joint, and a portion of the second reinforcing bar, thereby connecting the first PCa member and the second PCa member.

6. A grout injection tool having a tool body with a first end surface and a second end surface opposite the first end surface, The jig body is a through hole extending between the first end surface and the second end surface and through which a reinforcing bar is passed; An injection hole communicating with the through hole and into which grout is injected; a slit communicating with the injection hole and extending along the through hole between a position intersecting the injection hole and the first end surface, A2 step of preparing a grout injection jig, wherein the jig body is formed by a plurality of divided bodies that divide the through hole; a B2 step in which a first reinforcing bar is passed through a sheath tube provided in a first PCa member made of precast concrete, the first reinforcing bar extending from both a third end face opening where the sheath tube faces the third end face of the first PCa member and a fourth end face opening where the sheath tube faces the fourth end face of the first PCa member, one end of a second reinforcing bar provided in a second PCa member and one end of the first reinforcing bar are connected via a mechanical joint, and a plurality of the divided bodies are arranged at the position of the third end face opening while forming the through holes so as to sandwich the first reinforcing bar, and the peripheries of the plurality of the divided bodies are fastened with fastening bands to form and install the grout injection jig; A C2 step of installing the backer material or the separate grout injection jig at the position of the fourth end surface opening while passing the first reinforcing bar protruding from the fourth end surface opening through a through hole provided in the backer material or the through hole of the separate grout injection jig; Step D: Injecting grout from the injection hole of one of the grout injection jigs, and confirming that the grout that has flowed through the slit and the inside of the sheath tube has been discharged from the slit provided in the backer material or the injection hole of the other grout injection jig, thereby completing the grout injection; A method for connecting PCa members, characterized by including a step E of pouring concrete between the first PCa member and the second PCa member so as to bury a portion of the first reinforcing bar, the mechanical joint, and a portion of the second reinforcing bar, thereby connecting the first PCa member and the second PCa member.

7. In the step B1 or the step B2, spacers are installed at least near the third end surface opening and near the fourth end surface opening in a lower portion of the inside of the sheath tube; 7. A method for connecting PCa members according to claim 5 or 6, characterized in that the first reinforcing bar is supported from below by at least two of the spacers, and the first reinforcing bar is aligned inside the sheath tube.

8. In the A1 step or the A2 step, the jig body is prepared, and a spacer for extending into the sheath tube to support the reinforcing bar from below and for aligning the reinforcing bar inside the sheath tube is provided on the first end surface; 7. A method for connecting PCa members according to claim 5 or 6, characterized in that in steps B1, B2, C1, and C2, when the two grout injection jigs are installed at the positions of the third end face opening and the fourth end face opening, respectively, the spacer is inserted into the inside of the sheath tube to support the first reinforcing bar from below.

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