Precast beam joint structure
The precast beam joint structure addresses the challenge of beam member width by embedding a mechanical joint and using a cast-in-place concrete section to facilitate easier filling and anchoring, enhancing construction efficiency.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- TAKENAKA CORP
- Filing Date
- 2022-05-18
- Publication Date
- 2026-05-19
AI Technical Summary
Existing precast beam joint structures face challenges in narrowing the width of the beam member due to protruding reinforcements, which complicates the filling of mechanical joints with grout or filler materials.
A precast beam joint structure with a mechanical joint embedded in the column-beam joint, where one end opens onto the interior surface, and a cast-in-place concrete section is provided between the inner surface of the column-beam joint and the beam end face, allowing easier filling of the mechanical joint with grout and enhancing anchoring force through a mechanical anchoring body.
The structure allows for a narrower beam member width, improved workability in filling mechanical joints, and increased anchoring force, simplifying the construction process.
Smart Images
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Abstract
Description
Technical Field
[0007]
[0001] The present invention relates to a precast beam joint structure.
Background Art
[0002] A joint structure between a precast column-beam joint portion and a precast beam member is known (see, for example, Patent Documents 1 and 2).
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Patent Document 2
Summary of the Invention
[0008] The precast beam joint structure according to claim 1 comprises a precast beam member having a column-beam joint portion, a beam portion extending from the column-beam joint portion, a cantilever portion projecting out from the exterior surface of the beam portion on the exterior side, and a mechanical joint embedded in the column-beam joint portion, with one end opening to the interior surface of the column-beam joint portion on the interior side; and a beam member to which the main beam reinforcement is connected to the one end of the mechanical joint.
[0009] According to the precast beam joint structure of claim 1, the precast beam member has a column-beam joint, a beam section, an overhang, and a mechanical joint. The beam section extends from the column-beam joint. The overhang section cantileveres out from the exterior surface of the beam section on the outdoor side.
[0010] Here, a mechanical joint is embedded in the column-beam joint. One end of the mechanical joint opens onto the interior surface of the column-beam joint on the room side. The main reinforcement of the beam member is connected to one end of this mechanical joint.
[0011] Thus, in this invention, by embedding a mechanical joint in the column-beam joint, the width of the precast beam member (member width) can be narrowed compared to a configuration in which the main beam reinforcement protrudes from the inner surface of the column-beam joint.
[0012] The precast beam joint structure according to claim 2 is the precast beam joint structure according to claim 1, wherein the main beam reinforcement protrudes from the beam end face of the beam member, and a cast-in-place concrete section is provided between the inner surface of the column-beam joint and the beam end face of the beam member.
[0013] According to the precast beam joint structure of claim 2, a cast-in-place concrete section is provided between the inner surface of the column-beam joint and the beam end face of the beam member.
[0014] In this case, if the gap between the inner surface of the column-beam joint and the beam end face of the beam member is narrow, it becomes difficult to fill the mechanical joint embedded in the column-beam joint with grout, mortar, or other filler material while the main reinforcement bars of the beam member are inserted into the mechanical joint.
[0015] In contrast, in the present invention, as described above, a cast-in-place concrete section is provided between the inner surface of the column-beam joint and the beam end face of the beam member. Therefore, in the present invention, the gap between the inner surface of the column-beam joint and the beam end face of the beam member can be widened compared to a configuration in which a filler material such as grout is filled between the inner surface of the column-beam joint and the beam end face of the beam member.
[0016] Therefore, with the main reinforcement bars of the beam member inserted into the mechanical joint embedded in the column-beam joint, it becomes easier to fill the mechanical joint with grout or other filling material, thus improving workability.
[0017] The precast beam joint structure according to claim 3 is the precast beam joint structure according to claim 1 or claim 2, wherein a mechanical anchoring body connected to the other end of the mechanical joint is embedded in the column-beam joint portion.
[0018] According to the precast beam joint structure of claim 3, a mechanical anchoring body is embedded in the column-beam joint. The mechanical anchoring body is connected to the other end of the mechanical joint. This makes it possible to shorten the length of the mechanical joint while increasing the anchoring force of the mechanical joint to the column-beam joint. [Effects of the Invention]
[0019] As described above, according to the present invention, in a precast beam member having a protruding portion that extends outward from the outer surface on the outdoor side, the width of the precast beam member can be narrowed. [Brief explanation of the drawing]
[0020] [Figure 1] This is a plan view showing a first precast beam member and a second precast beam member to which a precast beam joint structure is applied in one embodiment. [Figure 2] It is a sectional view taken along line 2-2 of FIG. 1. [Figure 3] It is an exploded longitudinal sectional view of the first precast beam member and the second precast beam member shown in FIG. 2. [Figure 4] It is a longitudinal sectional view of a column-beam joint portion for explaining a method of filling a filler for a mechanical joint embedded in the column-beam joint portion. [Figure 5] (A) is a sectional view taken along line 5A-5A of FIG. 4, and (B) is a sectional view showing a state where a binding band is removed from the ring-shaped formwork shown in FIG. 5(A).
Embodiment for Carrying Out the Invention
[0021] Hereinafter, a precast beam joining structure according to an embodiment will be described with reference to the drawings.
[0022] (Precast Beam Joining Structure) In FIG. 1, a first precast beam member 10 and a second precast beam member 50 to which the precast beam joining structure of this embodiment is applied are shown. The first precast beam member 10 and the second precast beam member 50 are arranged so as to intersect (substantially orthogonally) with each other in a plan view.
[0023] (First Precast Beam Member) The first precast beam member 10 is made of precast concrete. This first precast beam member 10 has column-beam joint portions 12, two beam portions 20, and a balcony 24. The column-beam joint portions 12, the two beam portions 20, and the balcony 24 are integrally formed (precast) in a factory or the like. Note that the balcony 24 is an example of a projecting portion. Note that the first precast beam member 10 is an example of a precast beam member.
[0024] (Column-Beam Joint Portion) The column-beam joint 12 is formed in a rectangular shape when viewed from above. As shown in Figure 2, the column-beam joint 12 is positioned between the lower precast column member 30 and the upper precast column member 40, and is joined to these two precast column members. Together with the lower precast column member 30 and the upper precast column member 40, this column-beam joint 12 constitutes the outer perimeter column (side column) of the structure.
[0025] The column-beam joint section 12 is placed on the upper surface of the lower precast column member 30. Multiple sheath pipes 14 are embedded in the outer circumference of this column-beam joint section 12. The multiple sheath pipes 14 are arranged at intervals in the circumferential direction of the column-beam joint section 12. The multiple sheath pipes 14 are formed in a cylindrical shape and are embedded in the column-beam joint section 12 along the vertical direction. These sheath pipes 14 form multiple through holes that penetrate the column-beam joint section 12 in the vertical direction.
[0026] The lower precast column member 30 and the upper precast column member 40 are made of precast concrete. Furthermore, the lower precast column member 30 and the upper precast column member 40 are formed in a rectangular prism shape. In plan view, the outer shapes of these lower precast column member 30 and the upper precast column member 40 and the column-beam joint 12 are substantially identical.
[0027] Multiple main column reinforcements 32 and shear reinforcements (not shown) are embedded in the outer circumference of the lower precast column member 30. The upper ends of the multiple main column reinforcements 32 extend upward from the upper surface of the lower precast column member 30. These main column reinforcements 32 each penetrate vertically through multiple sheath pipes 14 embedded in the column-beam joint 12, and extend upward from the upper surface of the column-beam joint 12. The sheath pipes 14 are filled with a filler material such as grout.
[0028] The upper precast column member 40 is placed on the upper surface of the column-beam joint 12. Multiple main column reinforcements 42 and shear reinforcements (not shown) are embedded in the outer circumference of the upper precast column member 40. In addition, multiple mechanical joints 44 are embedded in the outer circumference of the lower end of the upper precast column member 40.
[0029] Multiple mechanical joints 44 have their lower ends inserted into their upper ends. Conversely, multiple main reinforcement bars 32 of the lower precast column member 30 are inserted into their lower ends. Each mechanical joint 44 is filled with grout or other filling material. As a result, the main reinforcement bars 32 of the lower precast column member 30 and the main reinforcement bars 42 of the upper precast column member 40 are connected via the mechanical joints 44.
[0030] Furthermore, the joints between the column-beam connection 12 and the lower precast column member 30 and the upper precast column member 40 are filled with a filler material such as grout or mortar.
[0031] Furthermore, in this embodiment, the main reinforcing bars 32 protruding from the upper surface of the lower precast column member 30 penetrate vertically through the column-beam joint portion 12 of the first precast beam member 10 and are connected to a mechanical joint 44 embedded in the lower end of the upper precast column member 40. However, the main reinforcing bars 42 protruding from the lower surface of the upper precast column member 40 may also penetrate vertically through the column-beam joint portion 12 of the first precast beam member 10 and be connected to a mechanical joint embedded in the upper end of the lower precast column member 30.
[0032] (beam) As shown in Figure 1, the two beam sections 20 extend outward from both sides of the column-beam joint section 12. Each beam section 20 has multiple main beam reinforcements 22 and shear reinforcements (not shown) embedded within it. The multiple main beam reinforcements 22 extend from the beam end faces of the beam sections 20. These main beam reinforcements 22 are connected to the main beam reinforcements of a concrete beam (not shown).
[0033] (balcony) A balcony 24 is provided on the exterior side of the column-beam joint 12 and the two beam sections 20. The balcony 24 extends across the two beam sections 20 and cantilever outwards from the exterior surfaces 12A and 20A of the column-beam joint 12 and the two beam sections 20. A drainage channel 26 is formed on the upper surface of the tip of the balcony 24. The drainage channel 26 is optional.
[0034] (Second precast beam member) As shown in Figure 2, the second precast beam member 50 is made of precast concrete. The second precast beam member 50 is located on the interior side of the column-beam joint 12 of the first precast beam member 10, and is erected between the column-beam joint 12 and a column (not shown). Note that the second precast beam member 50 is just one example of a beam member.
[0035] Multiple beam main reinforcements 52 and multiple shear reinforcements 54 are embedded in the second precast beam member 50. The multiple beam main reinforcements 52 protrude from the beam end face 50T of the second precast beam member 50. These beam main reinforcements 52 are connected to the column-beam joint portion 12 of the first precast beam member 10.
[0036] Specifically, multiple mechanical joints 16 are embedded in the column-beam joint 12. The multiple mechanical joints 16 are embedded on the interior side of the first precast beam member 10, along the width direction (arrow W direction) of the first precast beam member 10.
[0037] One end of each of the multiple mechanical joints 16 opens onto the interior surface 12B of the column-beam joint 12 on the interior side. The main beam reinforcement 52 of the first precast beam member 10 is inserted into one end of each of these mechanical joints 16. The other end of each of the multiple mechanical joints 16 is inserted into one end of each reinforcing bar 17. Each mechanical joint 16 is filled with a filler material, such as grout (not shown). In this way, the main beam reinforcement 52 and the reinforcing bar 17 are connected via the mechanical joints 16.
[0038] Furthermore, a mechanical anchoring body 18 is attached to the other end of the reinforcing bar 17. This mechanical anchoring body 18 enhances the anchoring force of the mechanical joint 16 to the column-beam joint 12.
[0039] The reinforcing bars 17 and mechanical anchoring bodies 18 may be provided as needed and can be omitted as appropriate. Furthermore, the number and arrangement of mechanical joints 16 can be changed as appropriate according to the number and arrangement of the main beam reinforcements 52.
[0040] The beam end face 50T of the second precast beam member 50 is positioned with a gap between it and the inner surface 12B of the column-beam joint 12. Cast-in-place concrete is poured into the space between the beam end face 50T of the second precast beam member 50 and the inner surface 12B of the column-beam joint 12. As a result, a cast-in-place concrete section 56 is provided between the beam end face 50T of the second precast beam member 50 and the inner surface 12B of the column-beam joint 12. Shear reinforcement bars 54 are embedded in the cast-in-place concrete section 56.
[0041] (Construction method for precast beam joint structure) Next, an example of a construction method for the precast beam joint structure according to this embodiment will be described.
[0042] Figure 3 shows a first precast beam member 10 in which a column-beam joint 12 is joined to a lower precast column member 30 and an upper precast column member 40. From this state, a second precast beam member 50 is lifted using a lifting machine or the like (not shown), and the beam end face 50T of the second precast beam member 50 is brought into contact with the inner surface 12B of the column-beam joint 12.
[0043] Furthermore, ring-shaped formwork 70 is attached to each of the multiple main beam reinforcements 52 that protrude from the beam end face 50T of the second precast beam member 50, and multiple shear reinforcements 54 are hooked onto them while being positioned closer to the beam end face 50T.
[0044] As shown in Figure 5(B), the ring-shaped formwork 70 is formed in a ring shape. A through-hole 72 into which the main beam reinforcement 52 is inserted is formed in the center of this ring-shaped formwork 70. In addition, a slit 74 reaching the through-hole 72 is formed on the circumferential surface 70S of the ring-shaped formwork 70. This slit 74 allows the ring-shaped formwork 70 to be separated.
[0045] Next, as shown by the arrow X in Figure 3, the beam end face 50T of the second precast beam member 50 is brought close to the inner surface 12B of the column-beam joint 12, and the multiple main beam reinforcements 52 protruding from the beam end face 50T are inserted into the multiple mechanical joints 16 embedded in the column-beam joint 12.
[0046] Next, as shown in Figure 4, the ring-shaped formwork 70 is slid along the main beam reinforcement 52 and brought into contact with one end of the mechanical joint 16. Then, as shown in Figure 5(A), the cable ties 80 wrapped around the circumferential surface 70S of the ring-shaped formwork 70 are tightened to close the slit 74 of the ring-shaped formwork 70. This closes the opening 16A (see Figure 4) at one end of the mechanical joint 16 with the ring-shaped formwork 70.
[0047] Next, as shown in Figure 4, fasteners 90 such as pipe racks are attached to the main beam reinforcement 52, and the ring-shaped formwork 70 is sandwiched between the fasteners 90 and the mechanical joint 16. In this state, the bolts 92 attached to the fasteners 90 are tightened to fix the fasteners 90 to the main beam reinforcement 52. This holds the ring-shaped formwork 70 between the mechanical joint 16 and the fasteners 90.
[0048] Next, a filler material G, such as grout, is filled into the mechanical joint 16 via an injection pipe 60 connected to one end of the mechanical joint 16. At this time, the fact that the filler material G has been filled into the mechanical joint 16 is confirmed by discharging the filler material G from a discharge pipe 62 connected to the other end of the mechanical joint 16. Note that the injection pipe 60 and discharge pipe 62 are not shown in Figures 2 and 3.
[0049] Next, after the filler material G has hardened, the bolts 92 attached to the fastener 90 are loosened and the fastener 90 is removed from the main reinforcement 52 of the beam. Also, as shown in Figure 5(B), the cable ties 80 are removed from the ring-shaped formwork 70. Then, the ring-shaped formwork 70 is removed from the main reinforcement 52 of the beam by cutting it along the slit 74.
[0050] Next, as shown in Figure 3, multiple shear reinforcement bars 54 are placed at a predetermined pitch, positioned towards the beam end face 50T side of the second precast beam member 50. In addition, conventional formwork is temporarily erected around the casting space between the beam end face 50T of the second precast beam member 50 and the inner surface 12B of the column-beam joint 12.
[0051] In this state, cast-in-place concrete is poured into the space between the beam end face 50T of the second precast beam member 50 and the inner surface 12B of the column-beam joint 12 (the pouring space), forming a cast-in-place concrete section 56. This joins the column-beam joint 12 and one end of the second precast beam member 50. After that, the conventional formwork is removed.
[0052] (action) Next, the operation of this embodiment will be described.
[0053] As shown in Figure 2, according to this embodiment, the first precast beam member 10 has a column-beam joint 12, two beam sections 20, a balcony 24, and a mechanical joint 16. The two beam sections 20 extend to both sides from the column-beam joint 12. The balcony 24 is provided across the two beam sections 20 and cantilever outward from the outer surfaces 12A of these beam sections 20 and the column-beam joint 12.
[0054] Here, a mechanical joint 16 is embedded in the column-beam joint 12. One end of the mechanical joint 16 opens onto the interior surface 12B of the column-beam joint 12 on the interior side. The main beam reinforcement 52, which protrudes from the beam end face 50T of the second precast beam member 50, is connected to one end of this mechanical joint 16.
[0055] Thus, in this embodiment, by embedding a mechanical joint 16 in the column-beam joint portion 12 of the first precast beam member 10, the width (member width) of the first precast beam member 10 can be narrowed compared to a configuration in which the main beam reinforcement 52 protrudes from the inner surface 12B of the column-beam joint portion 12.
[0056] Furthermore, a mechanical anchoring body 18 is embedded in the column-beam joint portion 12 of the first precast beam member 10. The mechanical anchoring body 18 is connected to the other end of the mechanical joint 16 via reinforcing bars 17. This makes it possible to shorten the length of the mechanical joint 16 while increasing the anchoring force of the mechanical joint 16 to the column-beam joint portion 12.
[0057] Furthermore, in this embodiment, a cast-in-place concrete section 56 is provided between the inner surface 12B of the column-beam joint section 12 of the first precast beam member 10 and the beam end face 50T of the second precast beam member 50.
[0058] In this case, if the gap between the inner surface 12B of the column-beam joint portion 12 of the first precast beam member 10 and the beam end surface 50T of the second precast beam member 50 is narrow, it becomes difficult to fill the mechanical joint 16 embedded in the column-beam joint portion 12 with the main beam reinforcement 52 of the second precast beam member 50.
[0059] In contrast, in this embodiment, as described above, a cast-in-place concrete section 56 is provided between the inner surface 12B of the column-beam joint section 12 of the first precast beam member 10 and the beam end face 50T of the second precast beam member 50. Therefore, when filling the space between the inner surface 12B of the column-beam joint section 12 and the beam end face 50T of the second precast beam member 50 with a filler material such as grout, the distance between the inner surface 12B of the column-beam joint section 12 and the beam end face 50T of the second precast beam member 50 can be increased.
[0060] Therefore, with the main beam reinforcement 52 of the second precast beam member 50 inserted into the mechanical joint 16 embedded in the column-beam joint 12, it becomes easier to fill the mechanical joint 16 with the filler material G, thus improving workability.
[0061] Furthermore, as shown in Figure 4, in this embodiment, when filling the mechanical joint 16 with filler material G, the ring-shaped formwork 70 attached to the main reinforcement bar 52 of the beam closes the opening 16A at one end of the mechanical joint 16. This prevents the filler material G from leaking out of the opening 16A at one end of the mechanical joint 16.
[0062] Furthermore, as shown in Figure 5(B), a slit 74 is formed in the ring-shaped formwork 70. This allows the main beam reinforcement 52 to easily remove the ring-shaped formwork 70 by loosening the cable ties 80 after filling the mechanical joint 16 with the filler material G and cutting the ring-shaped formwork 70 along the slit 74. Thus, workability is improved.
[0063] (modified version) Next, a modified example of the above embodiment will be described.
[0064] In the above embodiment, the balcony 24 extends across two beam sections 20 of the first precast beam member 10. However, the balcony 24 can be provided on at least one beam section 20. Furthermore, the balcony 24 can also be provided on a portion of the first precast beam member 10 in the longitudinal direction.
[0065] Furthermore, in the above embodiment, the overhang is a balcony 24. However, the overhang is not limited to a balcony 24; for example, it could be an overhanging slab (cantilever slab) or an awning.
[0066] Furthermore, in the above embodiment, the first precast beam member 10 is provided with two beam sections 20. However, the first precast beam member 10 can be provided with at least one beam section 20.
[0067] Furthermore, in the above embodiment, when filling the mechanical joint 16 with filler material G, the opening 16A of the mechanical joint 16 is temporarily closed with a ring-shaped formwork 70. However, the opening 16A of the mechanical joint 16 may be closed by other methods, not limited to the ring-shaped formwork 70. For example, the opening 16A of the mechanical joint 16 may be closed with formwork (disposable formwork), and the formwork may be embedded (permanently embedded) in the cast-in-place concrete section 56.
[0068] Furthermore, in the above embodiment, a cast-in-place concrete section 56 is provided between the inner surface 12B of the column-beam joint section 12 of the first precast beam member 10 and the beam end face 50T of the second precast beam member 50. However, it is also possible to narrow the gap between the inner surface 12B of the column-beam joint section 12 of the first precast beam member 10 and the beam end face 50T of the second precast beam member 50 and fill the gap with a filler material such as grout to join them.
[0069] Furthermore, in the above embodiment, the beam member joined to the column-beam joint 12 of the first precast beam member 10 is a second precast beam member 50 made of precast concrete. However, the beam member joined to the column-beam joint 12 of the first precast beam member 10 is not limited to being made of precast concrete, but may also be made of cast-in-place concrete or the like.
[0070] Furthermore, in the above embodiment, the upper precast column member 40 is joined to the column-beam joint portion 12 of the first precast beam member 10. However, the upper precast column member 40 can be omitted as appropriate.
[0071] Furthermore, in the above embodiment, the columns joined to the column-beam joint portion 12 of the first precast beam member 10 are the lower precast column member 30 and the upper precast column member 40. However, the columns joined to the column-beam joint portion 12 of the first precast beam member 10 are not limited to precast concrete construction, but may also be cast-in-place concrete construction or the like.
[0072] Although one embodiment of the present invention has been described above, the present invention is not limited to these embodiments, and various modifications may be used in appropriate combinations with one embodiment, and of course, the invention can be implemented in various forms without departing from the spirit of the present invention. [Explanation of Symbols]
[0073] 10. First precast beam member (precast beam member) 12 Column and beam joint section 12B Inner surface of the column-beam joint on the interior side 16 Mechanical couplings 18 Mechanical anchoring unit 20 Beam section 20A Exterior surface of the beam section 24 Balcony (projecting section) 50 Second precast beam member (beam member) 50T beam end face 52 Beam main reinforcement 56 Cast-in-place concrete section
Claims
1. A precast beam member having a column-beam joint, a beam extending from the column-beam joint, a projecting portion extending from the exterior surface of the beam on the outdoor side, and a mechanical joint embedded in the column-beam joint, with one end opening to the interior surface of the column-beam joint on the indoor side, The beam member to which the main reinforcement of the beam is connected to one end of the mechanical joint, A precast beam joint structure equipped with this feature.
2. The main reinforcement of the beam protrudes from the beam end face of the beam member, A cast-in-place concrete section is provided between the inner surface of the column-beam joint and the beam end face of the beam member. The precast beam joint structure according to claim 1.
3. A mechanical anchoring body connected to the other end of the mechanical joint is embedded in the column-beam joint. The precast beam joint structure according to claim 1 or claim 2.