JP2016079695A - Beam construction method, and precast plate for beam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a beam construction method and a precast plate for the beam that significantly reduce burdens when working on a beam mold at a construction site and save labors at the construction site, when constructing a reinforced concrete beam.SOLUTION: With the beam construction method, a beam is constructed by manufacturing in advance a precast plate 10 having a main reinforcement 12 on a beam bottom edge side embedded in a longer-side direction and a stirrup reinforcement 11 embedded in a shorter-side direction, as well as an end of the stirrup reinforcement exposed from a side surface 10a to make stirrup reinforcement anchoring parts 11a, 11b while the other end is exposed from a top surface 10b. A pair of precast plates is installed vertically such that the sides on which the stirrup reinforcement anchoring parts are exposed face each other, and concrete is cast in a space formed between the pair of precast plates installed to face each other, thereby embedding the stirrup reinforcement anchoring parts in the concrete, for forming the beam.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a method for constructing a reinforced concrete beam and a precast plate for the beam.

  Conventionally, in order to save labor in setting up a temporary frame at a construction site, it has been proposed to precast the side of the foundation beam. In Patent Document 1, a pair of precast concrete vertical plates with embedded reinforcing bars are placed on the pressure plate part, and the upper and lower beam main bars are arranged, and then concrete is placed between the vertical plates and the pressure plate part. A method for constructing the foundation beam for constructing the upper slab is proposed.

  In Patent Document 2, the side surface of the beam is made of a precast plate, the vertical bar that protrudes above and below the precast plate is arranged at the vertical slab position, the beam main bar and the horizontal bar are arranged, and between the precast plates and A construction method of reinforced concrete foundation beam is proposed. Made of reinforced concrete, laying sand and sacrificial concrete on the ground at the bottom of the excavation, arranging the upper and lower reinforcing bars that are the main bars of the mat slab, and installing the level adjustment cradle on the sacrificial concrete and forming the beam side surface on it The precast plates are installed at a required interval (FIG. 1).

  Patent Document 3 arranges a pair of precast concrete mold materials, each of which is formed by embedding a plurality of assembly bars extending in parallel along the longitudinal direction, separated from each other on the left and right sides, and also joins the same formwork material. A half precast member is proposed in which a plurality of sets are arranged in the longitudinal direction via a portion, and are connected and integrated with main bars arranged over the entire length by cast-in-place concrete.

Japanese Patent Publication No. 3-26738 Japanese Patent Laid-Open No. 5-287759 JP 2005-120702

  However, Patent Documents 1 and 2 are methods for constructing a foundation beam on a pressure plate, and are not intended for application to portions other than the pressure plate, and the main bars are excluded from the precast members. Patent Document 3 also excludes the main reinforcement from the precast member (FIG. 2), and it is necessary to use an assembly reinforcement which is not necessary for the structural calculation of the original RC (steel reinforced concrete) beam. Not.

  In view of the above-mentioned problems of the prior art, the present invention can greatly reduce the work related to the beam formwork at the construction site when constructing a reinforced concrete beam, thereby realizing labor saving of the field work. It is an object to provide a beam construction method and a beam precast plate.

A beam construction method for achieving the above object is a method of constructing a reinforced concrete beam,
Preceding a precast plate in which the main bars on the lower end of the beam are embedded in the longitudinal direction and the stapling bars are embedded in the lateral direction, and one end of the stirrup is exposed from the side surface, and the other end is exposed from the upper end surface. To produce
A pair of the precast plates are installed vertically so that the exposed side surfaces of the scallop fixing unit face each other,
The concrete is characterized in that a beam is constructed by fixing concrete in the concrete by placing concrete in a space formed by facing the pair of precast plates.

  According to this beam construction method, a pair of precast plates can be installed as both sides of the beam, so that the beam side mold is not required. Therefore, the assembly work including the side formwork separator at the construction site and the removal work thereof can be omitted. Therefore, the work related to the beam formwork at the construction site can be greatly reduced, and the prefabrication can be performed. In the precast plate, since the stirrup bars and the main bars on the beam lower end side are embedded, it is possible to reduce the work of arranging the stirrup bars and the main bars at the construction site. In this way, a significant labor saving in field work can be realized.

  In addition, the scallop anchoring part is put into the concrete by projecting the scallop streaks from the precast plate constituting the side of the beam to the center side of the beam (the space between the pair of precast plates) as the scallop fixing part and placing the concrete in the space. It can be fixed. Accordingly, the pair of precast plates can be integrated, and the scallop bars can be surely functioned as the shear reinforcement bars and the constraint bars of the beam main bars.

  In the beam construction method, the stapling fixing portion includes a horizontal portion that protrudes substantially horizontally from the side surface of the precast plate and is positioned on the lower end side of the beam, and a vertical portion that is bent substantially perpendicularly to the upper end side of the beam. It is preferable.

  Further, the other end side of the stapling bar exposed from the upper end surface of the precast plate corresponds to the height of the slab portion on which the concrete is placed when the precast plate is manufactured, and the upper end side of the beam It is preferable to hold the main muscle. Thereby, by placing concrete in the slab portion, the stirrup bars exposed from the upper end surface of the precast plate and the main bars on the upper end side of the beam can be reliably fixed in the concrete. In addition, this concrete placement enables concrete placement of the beam and floor slab in a lump, and further, the main reinforcement on the upper end side of the beam is held at the other end of the stirrup reinforcement exposed from the upper end face of the precast plate. Since the precast plate can be pre-manufactured in the state, the main bar arrangement work on the upper end side of the beam can be reduced, and eventually the main bar arrangement work on the lower end side and upper end side of the beam is simplified. Significant labor savings can be realized.

  In addition, when the pair of precast plates are installed facing each other, the other opposite ends of the scallop muscles are joined and connected by another scallop muscle, thereby connecting the scallop bars of the pair of precast plates. it can.

  Further, when the pair of precast plates are installed to face each other, the stapling fixing unit may be configured to intersect each other, and a reinforcing bar may be disposed inside the intersecting portion.

  Further, a reinforcing bar having a beam lower end portion and having a substantially U-shape may be arranged in the space so that the beam lower end portion corresponds to the horizontal portion of the stapling fixing portion.

  In addition, it is preferable to arrange a middle beam bar that satisfies the amount of main bars and shear reinforcement bars required in the space. When structural calculation requires more beam main reinforcement and shear reinforcement reinforcement, the middle beam reinforcement with stirrup and main reinforcement is placed in the space between the pair of precast plates. In this case as well, it is not necessary to separately arrange the stirrup muscles and the main muscles, and it is possible to realize a significant labor saving in the field work. After that, by placing the concrete, the middle beam can be reliably fixed in the concrete.

  Moreover, a beam with a wall can be constructed | assembled by letting the reinforcement of the wall of a concrete reinforcement structure pass in the said space.

  Further, one of the pair of precast plates may be omitted, and a formwork may be disposed on the omitted side. Thereby, for example, a wall-mounted beam with a wall attached to one side of the beam can be constructed using one precast plate.

Another beam construction method for achieving the above object is a method of constructing a reinforced concrete foundation beam,
Preceding a precast plate in which the main bars on the lower end of the beam are embedded in the longitudinal direction and the stapling bars are embedded in the lateral direction, and one end of the stirrup is exposed from the side surface, and the other end is exposed from the upper end surface. To produce
A pair of the precast plates are installed vertically on the flooring concrete plate so that the exposed side surfaces of the scallop fixing part face each other,
The middle beam bars that satisfy the amount of main reinforcing bars and the amount of shear reinforcing bars required for the space formed by the pair of precast plates facing each other are arranged,
A concrete beam is constructed by placing concrete in the space so that the middle beam stirrer and the stirrup fixing portion are fixed in the concrete.

  According to this beam construction method, since a pair of precast plates can be installed on the floor-mounted concrete plate as both sides of the foundation beam, no formwork of the foundation beam is required. Therefore, the assembly work including the formwork separator at the construction site and the removal work thereof can be omitted. Therefore, the work related to the basic beam formwork at the construction site can be greatly reduced, and the prefabrication can be performed. In the precast plate, since the stirrup bars and the main bars on the beam lower end side are embedded, it is possible to reduce the work of arranging the stirrup bars and the main bars at the construction site. In this way, a significant labor saving in field work can be realized.

  In addition, the scallop fixing part is projected into the center of the beam (the space between the pair of precast plates) from the precast plate that constitutes the side of the foundation beam as a scallop fixing part, and placed in the space to place the scallop fixing part in the concrete. Can be fixed. Accordingly, the pair of precast plates can be integrated, and the scallop bars can function reliably as the shear reinforcement bars and the main bars of the beam.

  In the beam construction method, a plurality of flat bars are preliminarily arranged on the floor-mounted concrete plate so that their upper surfaces are aligned, and are guided when the pair of precast plates are installed on the flat bar. It is preferable to fix the guide piece.

The beam precast plate for achieving the above object is a precast plate for constructing a reinforced concrete beam,
The beam lower end side main reinforcement is embedded in the longitudinal direction and the scallop muscle is embedded in the short side direction, and one end side of the scallop muscle is exposed from the side surface, and the other end side is exposed from the upper end surface,
A space formed when a pair of the precast plates are installed vertically so that the exposed side surfaces of the stapling fixing unit face each other or when the precast plates are installed vertically so that the side surfaces face the formwork By placing concrete on the steel, the stirrup fixing portion is fixed in the concrete to construct a beam.

  According to this precast plate for a beam, a pair of precast plates can be installed as both side portions of the beam, and the precast plate can be installed as a side portion of the beam. Therefore, the assembly work including the side formwork separator at the construction site and the removal work thereof can be omitted. Therefore, the work related to the beam formwork at the construction site can be greatly reduced, and the prefabrication can be performed. In the precast plate, since the stirrup bars and the main bars on the beam lower end side are embedded, it is possible to reduce the work of arranging the stirrup bars and the main bars at the construction site. In this way, a significant labor saving in field work can be realized.

  Further, the scallop fixing part can be fixed in the concrete by projecting the scallop bar as a scallop fixing part from the precast plate constituting the side part of the beam into the space on the center side of the beam and placing concrete in the space. Accordingly, the pair of precast plates can be integrated, and the scallop bars can be surely functioned as the shear reinforcement bars and the constraint bars of the beam main bars.

  In addition, the precast plate for beams can be standardized, whereby mass production can be achieved, cost can be reduced, and site precast can be supported. Moreover, since the lifting weight at the time of beam construction is reduced compared to the full precast method of beams, it is possible to reduce heavy equipment costs at the construction site.

  According to the present invention, when building a reinforced concrete beam, a beam construction method and a beam precast capable of significantly reducing the work related to the beam formwork at the construction site and realizing labor saving of the field work. Board can be provided.

It is a flowchart for demonstrating each process S01-S07 of the construction method of the beam by 1st Embodiment. It is the figure (a) which shows manufacture of the precast board of FIG. 1, and the figure (b) which shows a stock state. It is the side view (a) which shows the installation process of the precast board of FIG. 2, the side view (b) which shows the installation process of a middle beam reinforcement, and the side view (c) which shows the installation process of a half precast floor board. It is the principal part top view which looked at the state which has arrange | positioned the connection stirrup muscle of FIG.3 (b) from the beam upper direction. The side view (a) which shows the installation process of the precast board of FIG. 2 in the construction method of the beam by 2nd Embodiment, the side view (b) which shows the installation process of a reinforcing bar and a connection stirrup reinforcement, installation of a reinforcing bar and a connection stirrup reinforcement It is a side view (c) which shows the back. The side view (a) which shows the installation process of the precast board of FIG. 2 in the construction method of the beam by 3rd Embodiment, the side view (b) which shows the installation process of U-shaped type | mold reinforcement, installation of U-shaped type | mold reinforcement It is a side view (c) which shows the back. The side view (a) which shows the installation process of the precast board of FIG. 2 in the construction method of the beam by 4th Embodiment, the side view (b) which shows the installation process of a middle beam reinforcement, and a connection stirrup reinforcement, a middle beam reinforcement and connection It is a side view (c) which shows after installation of a scallop muscle. The side view (a) which shows the installation process of the precast board of FIG. 2 in the construction method of the foundation beam according to the fifth embodiment, the side view (b) which shows the installation process of the middle beam, the connection sparp after the installation of the middle beam It is a side view (c) which shows the installation process of a line | wire. It is a side view which shows process (a) (b) after installing a precast board, a middle beam reinforcement, etc. in 5th Embodiment. The side view (a) which shows the installation process of the precast board of FIG. 1 in the construction method of the beam by the modification of 4th Embodiment, the side view (b) which shows the installation process of a middle beam reinforcement, and a connection stirrup reinforcement, a middle beam It is a side view (c) which shows after installation of a line | wire and a connection scallop | muscle.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

<First Embodiment>
FIG. 1 is a flowchart for explaining the steps S01 to S07 of the beam construction method according to the first embodiment. FIG. 2 is a diagram (a) showing the production of the precast plate of FIG. 1 and a diagram (b) showing the stock state. 3 is a side view (a) showing the installation process of the precast plate of FIG. 1 for the beam construction, a side view (b) showing the installation process of the middle beam bars, and a side view (c) showing the installation process of the half precast board. ). FIG. 4 is a top view of the main part of the state where the connection stirrup muscles of FIG.

  The beam construction process of the present embodiment will be described with reference to FIGS. First, the precast board 10 is manufactured as shown in FIG. 2 (a) (S01), stocked as shown in FIG. 2 (b), and carried into the construction site as required (S02).

  In the precast plate 10 in FIG. 2A, the stirrup bars 11 are arranged in the transverse direction of the beam (lateral direction in FIG. 2A), and the main bars 12 on the lower end side of the beam are arranged in the longitudinal direction of the beam (arrows in FIG. 4). It is manufactured by placing concrete in a formwork (not shown) in the direction L). A predetermined number of the stirrup muscles 11 are arranged at predetermined intervals in the longitudinal direction. A pair of precast plates 10 are vertically installed as shown in FIG. 3A, and constitute both side portions of the beam.

  As shown in FIGS. 2 (a) and 2 (b), in the precast plate 10, the stirrup bar 11 and the main bar 12 are embedded in the concrete, but the stirrup bar 11 is horizontally oriented from the side surface 10a of the precast plate 10 at the lower end of the beam. It has a protruding horizontal portion 11a and a vertical portion 11b in which the horizontal portion 11a is bent perpendicularly to the beam upper end side. The horizontal portion 11a and the vertical portion 11b of the stapling muscle 11 constitute a stapling fixing portion. The vertical portion 11b on the distal end side is a free end.

  2 (a) and 2 (b), the scallop bar 11 holds the protrusion 11c protruding straight from the upper end surface 10b of the precast plate 10 and the main bar 13 on the beam upper end side at the tip of the protrusion 11c. And a holding portion 11d bent in a hook shape. The height from the upper end surface 10b of the precast plate 10 to the holding portion 11d of the protruding portion 11c is a height corresponding to a slab portion where concrete is placed later.

  In the precast plate 10, the main bars 12 on the lower side of the beam are embedded in the longitudinal direction corresponding to the length of the beam in a state where the main bars 12 are located at the inner corners of the right-angled part 11 e bent at a right angle of the scalloped bar 11. . Further, the main bars 13 on the side on the upper end side of the beam are held by a holding part 11d at the upper end of the protruding part 11c of the scallop bar 11 protruding from the upper end surface 10b. In this way, the main muscles 12 and 13 are restrained by the stirrup muscle 11.

  In the precast plate 10, an assembly bar 14 is arranged in the longitudinal direction on the upper end side of the beam so as to support the position of the stirrup bar 11. Further, the precast plate 10 is manufactured at a factory or the like away from the construction site and is carried into the construction site, but may be manufactured at an appropriate place on the construction site.

  Next, as shown in FIG. 3 (a), a pair of precast plates 10 and 10 are placed on a template 93 supported by a support 90 extending from the lower floor, and a horizontal portion 11a and a vertical portion of the stirrup muscle 11 are placed. It is installed vertically so that the protruding side surfaces 10a and 10a of 11b face each other (S03). At this time, in the space S formed between the side surfaces 10 a and 10 a of the pair of precast plates 10 and 10, a scallop fixing unit composed of the horizontal part 11 a and the vertical part 11 b of the scallop muscle 11 is located. The template 93 forms the lower surface of the beam in the lower part of the space S. Further, on both ends of the template 93, positioning portions 91 and 92 made of a crosspiece or the like for positioning the precast plates 10 and 10 are arranged.

  Next, the middle beam 20 is installed in the space S between the pair of precast plates 10 and 10 as shown in FIG. 3B (S04). The middle beam 20 includes a stapling bar 21 bent in a substantially rectangular shape elongated in the vertical direction, main bars 22 and 22 extending in the longitudinal direction (FIG. 4) on the beam lower end side, and a main bar 23 extending in the longitudinal direction on the beam upper end side. , 23. The main muscles 22 and 22 are located below the four corners of the scallop muscle 21, and the main muscles 23 and 23 are located above the four corners. The scallop bars 21 are arranged so as to wrap around the main bars 23, 23 on the upper end side of the beam and the main bars 22, 22 on the lower side of the beam, and both ends are wound around the main bar 23 in a hook shape and held. . In this way, the main muscles 22 and 23 are restrained by the stirrup muscle 21.

  Further, the middle beam 20 is arranged in order to satisfy the required amount of main reinforcement and shear reinforcement in the structural calculation. As shown in FIG. 4, the stirrup bars 21 of the intermediate beam 20 are arranged at a plurality of positions in the longitudinal direction of the beam, and correspond to the positions of the stirrup bars 11 embedded in the precast plate 10.

  After arranging the middle beam 20 as shown in FIG. 3B, the connecting stirrup 30 is arranged on the upper end side of the beam from above. As shown in FIGS. 3 (c) and 4, the connecting scallop bar 30 is arranged on the main bar 13 in the vicinity of the holding portion 11 d at the upper end of the scallop bar 11 in the pair of precast plates 10 and 10, and the middle beam bar 20 It arrange | positions so that the scallop | muscle 21 of the upper part of may be followed. The connecting scallop bars 30 are joined to the holding portion 11d of the scallop bar 11 by welding or the like, thereby connecting the scallop bars 11 and 11 of the pair of precast plates 10 and 10 at the upper part of the beam.

  Next, as shown by a broken line in FIG. 3C, half precast floor plates 96 and 97 for building a floor slab are horizontally installed above the beam precast plates 10 and 10 (S05). At this time, the height positions of the holding portion 11d at the upper end of the stirrup bar 11 and the stirrup bar 21 above the middle beam 20 in the precast plates 10 and 10 are higher than the lower surfaces of the half precast floor plates 96 and 97.

  Next, the slab reinforcement 97 is arranged on the upper surface side of the half precast floor boards 96, 97 as shown by the broken line in FIG. 3C (S06).

  Next, concrete is placed from above in FIG. 3C into the space S (S07). As a result, in the space S between the pair of precast plates 10 and 10, the stirrup fixing portion composed of the horizontal portion 11a and the vertical portion 11b protruding from the precast plates 10 and 10 is fixed in the concrete, and the middle beam bar The 20 stirrup bars 21 and the main bars 22 are fixed in the concrete. Further, between the half precast floor plates 96 and 97, the protrusions 11c, the holding parts 11d, the main bars 13, and the middle beam bars 20 at the upper end of the stirrup bars 11 are provided. The upper stirrup bars 21 and main bars 23 are fixed in the concrete. Furthermore, the slab reinforcement 97 is embed | buried in concrete in the upper surface side of the half precast floor boards 96 and 97. FIG. In this way, the beam is completed and the floor slab is also completed. Thereafter, the support 90 is removed, and the positioning portions 91 and 92, the template 93, and the like are also removed.

  According to the beam construction method of this embodiment, only a template for forming the lower surface of the beam is required as the beam formwork, and the pair of precast plates 10 and 10 are installed as both sides of the beam. Therefore, the beam side formwork is unnecessary. Therefore, the assembly work including the side formwork separator at the construction site and the removal work thereof can be omitted. Therefore, the work related to the beam formwork at the construction site can be greatly reduced, and the work on the site is greatly reduced. Can save labor.

  Further, in the precast plate 10 manufactured in advance, the stirrup muscle 11 and the main reinforcement 12 are embedded, and the main reinforcement 13 is held by the holding portion 11d at the tip of the stapling muscle 11 protruding from the upper end surface 10b. Each bar arrangement work of the muscle 11 and the main bars 12 and 13 is not necessary, and a significant labor saving of the field work can be realized.

  Further, the scallop muscles 11 are exposed and protruded from the precast plate 10 constituting the side portion of the beam to the center side of the beam (the space S between the precast plates 10 and 10) as the scallop fixing portions 11a and 11b. By placing the concrete, it is possible to fix the scallop fixing portions 11a and 11b having a free end on the front end side (vertical portion 11b) in the concrete. As a result, the precast plates 10 and 10 can be integrated, and the scallop bar 11 can function reliably as a shear reinforcement bar and a constraint bar for the beam main bar.

  Further, in the structural calculation, when the main bar amount and the shear reinforcing bar amount of the beam are further required, the middle beam bar 20 having the stirrup bar 21, the main bars 22, 22 and the main bars 23, 23 is simply arranged in the space S. Therefore, the individual bar arrangement work of the stirrup muscle 21 and the main muscles 22, 22, 23, and 23 is unnecessary, and a significant labor saving of the field work can be realized. Then, the concrete beam 20 can be reliably fixed in the concrete by placing the concrete.

  Further, each portion of the stirrup bar 11 and the middle beam bar 20 projecting upward from the upper end surface 10b of the precast plate 10 is located between the half precast floor plates 95 and 96 of the floor slab, and the concrete cast after the slab bar arrangement. By setting, it can be firmly fixed in concrete. In addition, the concrete placement after the slab placement can collectively put the beams and floor slabs together, so that a significant labor saving in the field work can be realized.

  In addition, the precast plate 10 can be standardized, whereby mass production can be achieved, cost reduction can be achieved, and site precast can be supported. Moreover, since the lifting weight at the time of beam construction is reduced compared to the full precast method of beams, it is possible to reduce heavy equipment costs at the construction site.

<Second Embodiment>
5A is a side view showing the installation process of the precast plate of FIG. 2 in the beam construction method according to the second embodiment, and FIG. 5B is a side view showing the installation process of the reinforcing bars and the connecting scallop bars. It is a side view (c) which shows after installation of a scallop muscle.

  Since the beam construction method according to the present embodiment is basically the same as that shown in FIGS. 1 to 4 except that the installation of the middle beam bars is omitted, the differences will be mainly described. As shown in FIG. 5A, the pair of precast plates 10 and 10 are vertically installed on the template 93, but the width of the beam is smaller than those in FIGS. The horizontal portions 11a and 11a of the scallop muscles 11 and 11 protruding from 10 intersect and overlap each other, and the vertical portions 11b and 11b come close to the opposite side surfaces 10a and 10a.

  Next, as shown in FIG. 5 (b), the stapling fixing portion composed of the horizontal portion 11a and the vertical portion 11b of the stapling muscle 11 intersects with each other, but the reinforcing bar 15 is between the intersecting vertical portions 11b and 11b. Is arranged from above. Next, the connecting scallop muscles 31 are arranged on the main muscle 13 in the vicinity of the holding portion 11d at the upper end of the scallop muscle 11 and joined to the holding portion 11d, thereby connecting the scallop muscles 11 and 11 at the upper part of the beam (see FIG. 4). ). The arrangement of the reinforcing bars 15 can prevent the vertical portions 11b and 11b of the stapling bars 11 and 11 from slipping out, and can be reliably fixed in the concrete placed in the space S.

  As described above, the installation of the precast plate 10, the arrangement of the reinforcing bars 15, and the arrangement of the connection stirrup bars 31 are completed as shown in FIG. 5C, and then the concrete is performed in the same manner as in steps S <b> 05 to S <b> 07 of FIG. 1. The beam and floor slab are completed by driving.

  According to the beam construction method of the present embodiment, even when the installation of the middle beam bars is omitted (when the middle beam bars are unnecessary), the same effects as those of the first embodiment can be obtained.

<Third Embodiment>
6A is a side view showing the installation process of the precast plate of FIG. 1 in the beam construction method according to the third embodiment, FIG. 6B is a side view showing the installation process of the U-shaped streak, and FIG. It is a side view (c) which shows after the installation of a pattern.

  The construction method of the beam according to the present embodiment is basically the same as that shown in FIGS. 1 to 4 except that the middle beam bars are omitted and the U-shaped bars are installed. The explanation is centered. As shown in FIG. 6A, the pair of precast plates 10 and 10 are vertically installed on the template plate 93.

  Next, as shown in FIG. 6B, the U-shaped streak 25 is installed from above in the space S between the precast plates 10 and 10. The U-shaped bars 25 are arranged at horizontal portions 25a, parallel portions 25b bent upward at right angles at both ends of the horizontal portions 25a, and reinforcing bars 26 arranged at the bent corners at both ends of the horizontal portions 25a and extending in the longitudinal direction of the beam. , 26. Horizontal portions 25a and parallel portions 25b of the U-shaped streaks 25 are arranged at a plurality of positions in the longitudinal direction of the beam, and correspond to the positions of the stapling streaks 11 embedded in the precast plate 10. When the U-shaped line 25 is arranged in the space S, the horizontal part 25 a is positioned on the beam lower end side and is positioned in the vicinity of the horizontal part 11 a of the sturrup line 11.

  Next, as shown in FIG. 6 (c), the connecting scallop muscle 30 is disposed on the main muscle 13 in the vicinity of the holding portion 11 d at the upper end of the scallop muscle 11, and joined to the holding portion 11 d, so that the scallop muscles 11, 11 are connected. It connects in the beam upper part (refer FIG. 4).

  As described above, as shown in FIG. 6C, the installation of the precast plate 10, the arrangement of the U-shaped streaks 25, and the connection stapling bars 30 are completed. Next, steps S05 to S07 in FIG. Similarly, beams and floor slabs are completed by placing concrete.

  According to the beam construction method of the present embodiment, the same effects as those of the first embodiment can be obtained even when the installation of the middle beam bars is omitted (when the middle beam bars are unnecessary), and The effect of shear reinforcement can be obtained by installing the letter-shaped streaks.

<Fourth Embodiment>
FIG. 7 is a side view (a) showing the installation process of the precast plate of FIG. 1 in the beam construction method according to the fourth embodiment, a side view (b) showing the installation process of the middle beam bars and the connecting stirrup bars, It is a side view (c) which shows after installation of a beam reinforcement and a connection stirrup reinforcement.

  Since the beam construction method according to the present embodiment is basically the same as that shown in FIGS. 1 to 4 except that the beam configuration is a walled beam, different points will be mainly described. As shown in FIG. 6A, a pair of precast plates 10 and 10 are placed on a support plate 94 and installed vertically for beam construction. Below the precast plates 10, 10, a formwork 95 for the construction of the lower floor wall is arranged. A support plate 94 is located at the upper end of the mold 95.

  A pair of reinforcing bars 40, 40 on the wall is arranged inside the mold 95, and the reinforcing bars 40, 40 extend through the space S between the precast plates 10, 10 further upward. Reinforcing bars 41 are arranged at predetermined intervals inside the pair of reinforcing bars 40.

  Next, as shown in FIG. 6 (b), the middle beam 20 is installed from above, and the connecting scallop 30 is arranged.

  As described above, as shown in FIG. 7C, the precast plate 10 so that the reinforcing bars 40, 40 extending upward from the inside of the mold 95 for wall construction pass through the space S between the precast plates 10, 10. , 10 are arranged, and the arrangement of the middle beam 20 and the arrangement of the connecting stirrup 30 are completed. Next, the walls, beams and floor slabs of the lower floor are completed by concrete placement in the same manner as in steps S05 to S07 in FIG. In this way, a walled beam can be constructed.

  According to the beam construction method of the present embodiment, the same effects as those of the first embodiment can be obtained even in the case of construction of a walled beam.

  Next, a modification of the construction method of the walled beam in FIG. 7 will be described with reference to FIG. FIG. 10 is a side view (a) showing the installation process of the precast plate of FIG. 1 in the beam construction method according to the modification of the fourth embodiment, and a side view (b) showing the installation process of the middle beam bars and the connecting stirrup bars. ), A side view (c) showing the post-installation of the middle beam bar and the connection stirrup bar.

  The walled beam in FIG. 7 has a configuration in which the wall is located in the center of the beam. However, the beam construction method in FIG. 10 is to construct a beam having a configuration in which the wall is attached to one side. In other words, this example is basically the same as FIG. 7 except that a normal formwork is arranged on the wall side and a precast plate is arranged on the side without the wall, so that the description will focus on the differences. To do.

  As shown in FIG. 10A, the mold 70 includes side molds 71 and 72 for forming walls and a template 73 for forming the lower surface of the beam. The beam precast plate 10 shown in FIG. 2 is arranged on the template 73 and is positioned by being guided by the positioning portion 74. The beam-side side formwork 71 extends from below to the template 73 and forms a beam-side lower wall surface. Further, the side mold 72 on the wall side extends from below to the same height as the upper end surface 10b of the precast plate 10 to form a wall surface on the opposite side of the beam. A pair of reinforcing bars 40 and 40 are arranged in the vertical direction between the side molds 71 and 72.

  Next, as shown in FIG. 10B, the middle beam 20 is disposed from above into a space SS formed between the side surface 10 a of the precast plate 10 and the side mold frame 72 on the wall side. Furthermore, the connection stirrup muscle 30 is arrange | positioned.

  As described above, the formwork 70 is arranged as shown in FIG. 10C, the precast plate 10 is arranged, and the arrangement of the middle beam reinforcement 20 and the arrangement of the connecting stirrup reinforcement 30 are completed. Next, a wall, a beam, and a floor slab are completed by concrete placement as in steps S05 to S07 in FIG. The wall is located on the right side of the beam in FIG. In this way, it is possible to construct a walled beam having a configuration in which the wall is attached to one side of the beam.

<Fifth Embodiment>
FIG. 8 is a side view (a) showing the installation process of the precast plate of FIG. 1 in the construction method of the foundation beam according to the fifth embodiment, a side view (b) showing the installation process of the middle beam, It is a side view (c) which shows the installation process of a connection stirrup muscle after installation. FIG. 9 is a side view showing steps (a) and (b) after the precast plate, the middle beam streaks, etc. of FIG. 8 are installed.

  The method for constructing a beam according to the present embodiment is basically the same as that shown in FIGS. 1 to 4 except that the configuration of the beam is a basic beam, and therefore, different points will be mainly described. As shown in FIG. 8 (a), when placing the flooring concrete plate 80 into concrete, the flat bars 81 are arranged at predetermined intervals so that the upper surfaces thereof are aligned, and concrete is placed. Next, the guide piece 82 is fixed to the flat bar 81 before the precast plate is built.

  Next, as shown in FIGS. 8A and 8B, the pair of precast plates 10 and 10 are installed on the floor-discarded concrete plate 80. At this installation, each precast plate 10 is a guide piece 82. Is guided and positioned. In the precast plate 10, assembly bars 55 and 55 for width stop bars are arranged below the protruding portion 11c of the scallop bar 11 protruding from the upper end surface 10b.

  Next, as shown in FIG. 8 (b), the middle beam bars 50 are arranged in the space S between the precast plates 10 and 10 from above. The middle beam reinforcement 50 has the same configuration as that of the middle beam reinforcement 20 of FIGS. 1 to 4, but the amount of the main reinforcement 52 on the lower end side of the beam and the main reinforcement 53 on the upper end side of the beam is increased. ing.

  Next, as shown in FIG. 8 (c), the width stop bars 56 are arranged and fixed on the upper end surfaces 10 b of the precast plates 10 and 10 using the assembly bars 55 and 55. Thereby, the space | interval between the precast boards 10 and 10 is maintained. Further, the connecting scallop muscles 32 are disposed on the main muscle 13 in the vicinity of the holding portion 11d at the upper end of the scallop muscle 11 and joined to the holding portion 11d, thereby connecting the scallop muscles 11 and 11 at the upper part of the beam.

  Next, as shown in FIGS. 9 (a) and 9 (b), the reinforcing material 85 is disposed on both sides or one side of the precast plates 10 and 10 diagonally from the floor-discarded concrete plate 80, and then the soil is backfilled. The precast plates 10 and 10 are located in the ground 89. The flat deck 86 is disposed on the ground 89, and then the foundation beam and the floor slab are completed by concrete placement in the same manner as in steps S05 to S07 in FIG. In this way, the foundation beam can be constructed in the ground.

  According to the foundation beam construction method of the present embodiment, the same effects as those of the first embodiment can be achieved even in the construction of the foundation beam. In particular, since there is no need for a formwork for constructing the foundation beam, no work on the foundation beam formwork at the construction site is required, and a significant labor saving of the field work can be realized.

  As described above, the modes for carrying out the present invention have been described. However, the present invention is not limited to these, and various modifications can be made within the scope of the technical idea of the present invention. For example, in the construction of the beam in FIG. 3 and the foundation beam in FIG. 8, a main bar at the beam center side may be added to the precast plate 10 as necessary.

  Moreover, the method of constructing a beam using one precast plate and a formwork is not limited to the case of FIG. 10, and may be applied to construction of other beam configurations.

  According to the present invention, it is possible to greatly reduce the work related to the beam formwork at the construction site, and to realize the labor saving of the site work, it is possible to contribute to the reduction of the construction cost of the reinforced concrete building / structure, In addition, it is possible to cope with labor shortages at construction sites.

DESCRIPTION OF SYMBOLS 10 Precast board 10a Side surface 10b Upper end surface 11 Sturrup muscle 11a Horizontal part 11b Vertical part 11c Protrusion part 11d Holding | maintenance part 12 and 13 Main bar 20 Middle beam 21 Stirp bar 22 and 23 Main bar 25 U-shaped line 25a Horizontal part 25b Parallel part 30 to 32 Connecting scallop bars 50 Middle beam bars 51 Sturrup bars 52 and 53 Main bars 82 Guide pieces 85 Reinforcement materials 96 and 97 Half-precast floor board L Beam longitudinal direction S Space

Claims (12)

A method of constructing a reinforced concrete beam,
Preceding a precast plate in which the main bars on the lower end of the beam are embedded in the longitudinal direction and the stapling bars are embedded in the lateral direction, and one end of the stirrup is exposed from the side surface, and the other end is exposed from the upper end surface. To produce
A pair of the precast plates are installed vertically so that the exposed side surfaces of the scallop fixing unit face each other,
A beam construction method, wherein concrete is cast in a space formed by the pair of precast plates facing each other, thereby constructing a beam by fixing the stirrup fixing portion in the concrete.   The said stapling fixing | fixed part has the horizontal part which protrudes substantially horizontally from the said side surface of the said precast board, and is located in the lower end side of a beam, and the vertical part bent substantially perpendicularly | vertically to the beam upper end side. How to build the beam.   When the precast plate is manufactured, the other end side of the stapling bar exposed from the upper end surface of the precast plate is configured to correspond to the height of the slab portion where the concrete is placed, and the main bar on the upper end side of the beam is formed at the other end. The method for constructing a beam according to claim 1, wherein the beam is held.   The method for constructing a beam according to claim 3, wherein when the pair of precast plates are installed to face each other, the other opposite ends of the scallop bars are joined and connected by another scallop bar.   5. The beam according to claim 1, wherein when the pair of precast plates are installed to face each other, the stapling fixing portions are configured to intersect each other, and reinforcing bars are disposed inside the intersecting portions. Construction method.   The beam construction method according to claim 2, wherein a reinforcing bar having a beam lower end portion and having a substantially U-shape is disposed in the space so that the beam lower end portion corresponds to a horizontal portion of the stirrup fixing portion. .   The beam construction method according to any one of claims 1 to 4, wherein a middle beam bar that satisfies a necessary main bar amount and a shear reinforcement bar amount is disposed in the space.   The beam construction method according to any one of claims 1 to 7, wherein a beam with a wall is constructed by passing a reinforcement of a concrete reinforced wall through the space.   The method for constructing a beam according to any one of claims 1 to 8, wherein one of the pair of precast plates is omitted, and a formwork is arranged on the omitted side. A method of constructing a reinforced concrete foundation beam,
Preceding a precast plate in which the main bars on the lower end of the beam are embedded in the longitudinal direction and the stapling bars are embedded in the lateral direction, and one end of the stirrup is exposed from the side surface, and the other end is exposed from the upper end surface. To produce
A pair of the precast plates are installed vertically on the flooring concrete plate so that the exposed side surfaces of the scallop fixing part face each other,
The middle beam bars that satisfy the amount of main reinforcing bars and the amount of shear reinforcing bars required for the space formed by the pair of precast plates facing each other are arranged,
A method for constructing a beam, comprising constructing a foundation beam by placing concrete in the space so that the middle beam stirrer and the stirrup fixing portion are fixed in the concrete. A plurality of flat bars are preliminarily arranged on the flooring concrete board so that their upper surfaces are aligned,
The beam construction method according to claim 9, wherein a guide piece for guiding the pair of precast plates is installed on the flat bar. A precast plate for building a reinforced concrete beam,
The beam lower end side main reinforcement is embedded in the longitudinal direction and the scallop muscle is embedded in the short side direction, and one end side of the scallop muscle is exposed from the side surface, and the other end side is exposed from the upper end surface,
A space formed when a pair of the precast plates are installed vertically so that the exposed side surfaces of the stapling fixing unit face each other or when the precast plates are installed vertically so that the side surfaces face the formwork A precast plate for a beam, in which a concrete is constructed by placing concrete on the concrete to fix the stirrup fixing portion in the concrete.

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