JP7823815B2 - Installation method of construction jig and spacer - Google Patents

Description

The present invention relates to a construction jig and a spacer installation method.

Conventionally, spacers for reinforcing bars used in composite slab structures have been known, which have a peak portion, a valley bottom portion, and a sloped portion connecting these, and which support reinforcing bars on deck plates with a corrugated cross section intersecting the longitudinal direction (see, for example, Patent Document 1). The spacer in Patent Document 1 is configured by combining two gate-like structures each having two support legs and two mounting portions, and each gate supports the load of a wire mesh or the like, while distributing the load overall to the four support legs.

Japanese Patent Application Laid-Open No. 2020-060047

Figure 3 shows an example of a spacer 300. A known spacer 300 is made of steel plate and includes a support portion 310, a pair of legs 320, and a pair of engaging portions 330. This type of spacer 300 is installed on a deck plate, for example, at a construction site where a composite slab structure using a specified deck plate is being constructed.

The spacers 300 engage with the deck plate at the engagement portion 330, and workers had to engage each of the multiple spacers 300 to the deck plate on-site. The task of engaging (installing) the spacers 300 to the deck plate was a significant burden for workers, and there was a demand for improved work efficiency.

The present invention was developed in consideration of the above-mentioned issues, and aims to provide technology that reduces the workload of installing spacers on deck plates.

The construction jig of the present invention, which solves the above-mentioned problems, is a construction jig that rotates and installs spacers that support longitudinally arranged rebar at the valley bottoms of a deck plate that has a corrugated shape formed by multiple peaks and valley bottoms that are connected to each other via inclined sections. The construction jig is equipped with a cylindrical engaging member with at least one open end that engages with the spacer. The engaging member has a circumferential surface as its inner circumferential surface, and at least two engaging portions formed on the inner circumferential surface to engage with the spacer, extending circumferentially from one end on the opening side that accommodates the spacer to the other end on the opposite side. When the engaging portions are engaged with the spacer, the engaging member is moved along its axis, thereby rotating the spacer along the engaging portions.

In one aspect of the construction jig of the present invention, it is preferable that the engagement portions extend parallel to each other at radially opposing positions.

In one aspect of the construction jig of the present invention, it is preferable that the at least two engaging portions, excluding at least one end portion on the one end side and the other end portion on the other end side, do not overlap with each other on the axis of the engaging member.

In one aspect of the construction jig of the present invention, it is preferable that the engagement portion extend over an angular range of at least 90° between one end on the one end side and the other end on the other end side.

In one aspect of the construction jig of the present invention, the engaging member preferably has a closed end at the other end and is equipped with an operating member connected to the closed side of the engaging member for moving the engaging member, which is engaged with the spacer, in the direction of the axis.

The spacer installation method of the present invention, which solves the above-mentioned problems, is an installation method in which the spacer is rotated using the installation jig and installed on the deck plate, and is characterized by including the following steps: a temporary placement step in which the spacer is temporarily placed in the valley bottom; an engagement step in which the installation jig engages the spacer installed in the valley bottom; a rotation step in which the installation jig engaged with the spacer is pushed toward the deck plate to rotate the spacer; and a locking step in which the spacer is locked to the deck plate.

This invention reduces the workload of installing spacers on deck plates.

FIG. 10 is a diagram showing a composite slab using a deck plate with spacers. FIG. 1 is a perspective view showing a composite slab with the concrete portion partially removed. FIG. 2 is a front view illustrating the configuration of the deck plate. FIG. 2 is a perspective view illustrating a configuration of a spacer. FIG. 1 is a perspective view showing a construction jig according to the present embodiment. FIG. 2 is a plan view of the cylindrical member as viewed from the opening side. FIG. 2 is a cross-sectional view taken along the axis of the cylindrical member. FIG. 3 is a development view of the inner circumferential surface of the cylindrical member. FIG. 10 is a diagram showing a state in which a spacer is temporarily placed on a deck plate. 1 is a plan view showing an engagement state between a construction jig and a spacer according to the present embodiment. FIG. 10A and 10B are diagrams showing a process of rotating a spacer using a construction jig. FIG. 10 is a diagram showing a state in which the spacer rotates. 10A and 10B are diagrams showing a process of engaging the spacer with the deck plate using an installation jig. FIG. 10 is a view showing a state in which the spacer is engaged with the deck plate. FIG. 10 is a perspective view of a construction jig according to Modification 1. FIG. 10 is a perspective view of a construction jig according to Modification 2.

Embodiments of the present invention will be described below with reference to the drawings. In the following description, components common to each embodiment will be given the same reference numerals, and repeated explanations will be omitted. It should also be noted that the drawings are schematic, and the dimensional relationships and ratios of each element may differ from reality. The drawings may also contain parts with different dimensional relationships and ratios.

<Synthetic slab>
FIG. 1A is a diagram showing a composite slab 100 using a deck plate 200 with spacers. FIG. 1B is a perspective view showing the composite slab 100 with the concrete section 600 partially removed. The composite slab 100 according to this embodiment is used, for example, for the floor or roof of a steel frame structure. The composite slab 100 includes a deck plate 200, spacers 300, reinforcing bars 400 as reinforcing materials, a welded wire mesh 500, and a concrete section 600. The deck plate 200 is placed between beams, for example, H-shaped steel beams, arranged opposite each other in a structure.

[Deck plate]
2 is a front view illustrating the configuration of the deck plate 200. The deck plate 200 is a corrugated steel plate formed by roll forming or the like of a thin steel plate that has been subjected to a surface treatment such as galvanization. The deck plate 200 has a peak portion 210, a valley bottom portion 220, and an inclined portion 230. Note that the deck plate 200 does not necessarily have to be subjected to a surface treatment such as galvanization.

In the following, the direction in which the deck plate 200 spans between beams is referred to as the longitudinal direction (length direction) L of the deck plate 200, and the direction in which the deck plate 200 is laid out, intersecting the longitudinal direction L, is referred to as the transverse direction (width direction) W. The deck plate 200 has a wave-like shape in which peaks 210 and valleys 220, each extending in the longitudinal direction L, are connected to each other in the transverse direction W via inclined portions 230.

The deck plate 200 itself consists of two peaks 210, one valley 220, and two pairs of slopes 230, and is formed into a wave-like shape in cross section along the short direction W. The deck plate 200 may be end-closed at both ends in the long direction L.

The peak portion 210 is a flat, plate-shaped portion located above the beam when the beam is spanned between them, and extends in the longitudinal direction L. The peak portion 210 has a groove 211. The groove 211 is formed so as to be recessed toward the valley bottom 220. The groove 211 extends in the longitudinal direction L, and when there is only one groove 211, it is located near the center in the lateral direction W. The groove 211 in the peak portion 210 improves the strength of the peak portion 210. There is no limit to the number of grooves 211 formed in the peak portion 210; multiple grooves 211 may be formed, or there may be no grooves at all.

The valley bottom 220 is parallel or approximately parallel to the peak 210 and is a flat portion that rests on the beam relative to the peak 210 when the beam is spanned. The valley bottom 220 is a plate-like portion extending in the longitudinal direction L. The valley bottom 220 does not overlap with the peak 210 in the lateral direction W. The valley bottom 220 may also have a protruding ridge that extends along the longitudinal direction L and protrudes toward the peak 210.

The inclined portion 230 is a portion that connects the peak portion 210 and the valley bottom portion 220, and is a plate-shaped portion that extends in the longitudinal direction L. The inclined portion 230 extends obliquely from both ends of the peak portion 210 toward the valley bottom portion 220 in the short direction W. The inclined portion 230 is inclined so as to form a predetermined angle, for example, an obtuse angle, with respect to the peak portion 210 and the valley bottom portion 220. Note that the inclined portion 230 may be formed with a convex ridge portion that extends along the longitudinal direction L and protrudes toward the inclined portion 230 that faces across the valley bottom portion 220, or with multiple convex portions arranged at a predetermined interval in the longitudinal direction L.

A bulge 241 is formed in the transition 240 between the valley bottom 220 and the inclined portion 230. The bulge 241 is a portion that protrudes on opposite sides of the pair of inclined portions 230. In other words, the bulge 241 in the inclined portions 230 that face each other across the valley bottom 220 bulge in directions that bring them closer together.

An engagement groove (dovetail groove) 242 with which the spacer 300 engages is formed between the bulge 241 and the valley bottom 220. The cross section of the engagement groove 242 along the short direction W is curved. That is, in a pair of opposing inclined portions 230 on one surface of the deck plate 200, the engagement grooves 242 are formed to face each other and curve away from each other. The engagement portions 330 of the spacer 300, described below, enter the engagement groove 242. The spacer 300 engages with the deck plate 200 by fitting into the opposing engagement portions 330 across the valley bottom 220.

[Spacer]
A pair of engaging portions 330 (described later) enter and engage with opposing engaging grooves 242 of the spacer 300, fixing the position of the spacer 300 relative to the deck plate 200, and the bulging portions 241 prevent the spacer 300 from coming out of the engaging grooves 242. In this fixed state, the spacer 300 supports the reinforcing bars 400 from below, and can maintain a distance from the reinforcing bars 400 arranged on the deck plate 200.

Figure 3 is a perspective view illustrating the configuration of the spacer 300. Multiple spacers 300 are provided at predetermined intervals in the longitudinal direction L at the valley bottom 220 on one surface (top surface) of the deck plate 200. When installed at the valley bottom 220, the spacers 300 support the reinforcing bars 400 arranged along the longitudinal direction L of the deck plate 200 at a position beyond the crest 210 and spaced a predetermined height from the valley bottom 220. The spacers 300 support the reinforcing bars 400 along the longitudinal direction L from the valley bottom 220 side.

The spacer 300 is formed, for example, from a steel plate. The spacer 300 mainly comprises a support portion 310, a pair of legs 320, and a pair of engaging portions 330. The spacer 300 is a member in which the support portion 310, the pair of legs 320, and the pair of engaging portions 330 are continuously and integrally formed. The direction in which the support portion 310 supports the reinforcing bar 400 coincides with the longitudinal direction L of the deck plate 200.

The support portion 310 is a portion that supports the reinforcing bar 400 and is formed, for example, in a rectangular or approximately rectangular shape in a plan view. The support portion 310 is located at the uppermost position when the spacer 300 is installed on the deck plate 200. The support portion 310 has, for example, one recess 311. When the spacer 300 is installed on the deck plate 200, the recess 311 is formed as an arc-shaped recess toward the valley bottom 220 of the deck plate 200 and extends along the longitudinal direction L of the deck plate 200. The recess 311 receives the reinforcing bar 400 along its extension direction (longitudinal direction L).

The pair of legs 320 extend from a pair of opposing edges of the support portion 310 to the same side at a predetermined angle relative to the main surface of the support portion 310. The pair of legs 320 are arranged at an obtuse angle relative to the support portion 310, with one end of each extending from the support portion 310 connected to the support portion 310, and extend away from each other from the support portion 310. In other words, the width 320D between the pair of legs 320 changes continuously along the direction of the height 300H of the spacer 300; specifically, it increases from the support portion 310 side toward the engagement portion 330 side.

The pair of legs 320 are formed from a single continuous steel plate and are therefore elastically deformable so as to move towards and away from each other. An engagement portion 330 is provided at the other end of each leg 320 opposite the support portion 310 (the other end in the extension direction).

The pair of engaging portions 330 each extend away from the other end of each leg portion 320. When the spacer 300 is installed on the deck plate 200, the pair of engaging portions 330 extend parallel or approximately parallel to the support portion 310 along the short direction W. One end of each of the pair of engaging portions 330 is connected to the leg portion 320.

The pair of engagement portions 330 engage with the opposing engagement grooves 242 of the deck plate 200, thereby preventing the spacer 300 from being removed from the deck plate 200. This keeps the spacer 300 attached to the deck plate 200. The pair of engagement portions 330 are in contact with the valley bottom 220 when the spacer 300 is attached to the deck plate 200.

The pair of engaging portions 330 have two corners 331, 332 on the free end (other end) side. One corner 331 is a part where an edge extending from leg portion 320 and an edge facing leg portion 320 intersect at a right angle or approximately a right angle. The other corner 332 is located on the opposite side of one corner 331, and is a part where the edge extending from leg portion 320 and the edge facing leg portion 320 are connected in a rounded, arc-like shape.

In each engagement portion 330, the corners 331 and 332 are formed at diagonally opposite positions. This is because when the spacer 300 is rotated to engage the engagement portion 330 with the engagement groove 242, the corner 332 is positioned on the leading side in the rotational direction of the engagement portion 330, preventing it from getting caught in the engagement groove 242 and allowing for smooth rotation so that the engagement portion 330 can engage with the engagement groove 242.

[Rebar, welded wire mesh]
The reinforcing bars 400 are supported by a plurality of spacers 300 provided along the longitudinal direction L of the deck plate 200 and are arranged to extend in the longitudinal direction L of the deck plate 200. Specifically, the reinforcing bars 400 are placed in recesses 311 of the support portions 310 of the spacers 300 that are engaged with the engagement grooves 242 of the deck plate 200, and are arranged so that the reinforcing bars 400 do not roll off the support portions 310.

The reinforcing bars 400 are, for example, deformed reinforcing bars made by rolling steel to create uneven protrusions called ribs or nodes on the surface. However, this is not limited to this, and various shapes and types of reinforcing bars, such as round steel or square steel, or rods made of other materials may also be used as long as they function as reinforcing materials for the composite slab 100. The welded wire mesh 500 is, for example, formed into a grid shape using steel wire and is placed on top of the spacers 300 and reinforcing bars 400.

[Concrete section]
The concrete section 600 is formed by pouring and solidifying concrete onto one surface (top surface) of the deck plate 200. The concrete section 600 is poured so as to cover the spacers 300, the reinforcing bars 400, and the welded wire mesh 500, and after the concrete section 600 has solidified, the spacers 300, the reinforcing bars 400, and the welded wire mesh 500 are embedded within the concrete section 600.

<Construction jig>
To install the spacers 300 on the deck plate 200, the worker rotates the spacers 300, which have been temporarily placed on the deck plate 200, clockwise or counterclockwise, for example, by 90 degrees, so that the engagement portions 330 of the spacers 300 fit into the engagement grooves 242 of the deck plate 200. This operation is performed in a bent-over position, which places a great burden on the worker who installs the multiple spacers 300 that have been temporarily placed on the deck plate 200.

Furthermore, in order to make it easier for the engagement portion 330 of the spacer 300 to enter the engagement groove 242 of the deck plate 200, the pair of legs 320 must be brought closer together and rotated. However, because the spacer 300 is made of steel plate, it requires a great deal of effort for a worker to manually bring the pair of legs 320 of the spacer 300 closer together.

For this reason, the construction jig 1 according to this embodiment is used. The construction jig 1 engages with the spacer 300, rotates the spacer 300, and inserts the engagement portion 330 into the engagement groove 242 of the deck plate 200 to lock the spacer 300 to the deck plate 200.

The construction jig 1 of this embodiment is a construction jig that rotates and installs a spacer 300 that supports reinforcing bars 400 arranged in the longitudinal direction L at the valley bottoms 220 of a deck plate 200 that has a wave-shaped configuration in which multiple peaks 210 and valley bottoms 220 that are connected to each other via inclined portions 230. The spacer 300 supports reinforcing bars 400 arranged in the longitudinal direction L at the valley bottoms 220 of the deck plate 200. The construction jig 1 is characterized in that the construction jig 1 includes a cylindrical member (engaging member) 10 with at least one open end that engages with the spacer 300. The cylindrical member 10 has a circumferential surface as its inner peripheral surface 14, and at least two engaging protrusions (engaging portions) 21, 22 that are formed on the inner peripheral surface 14 to engage with the spacer 300 and extend circumferentially from one end on the opening 12 side that accommodates the spacer 300 to the other end on the opposite side. When the engaging protrusions 21, 22 are engaged with the spacer 300, the cylindrical member 10 is moved along the axis x, thereby rotating the spacer 300 along the engaging protrusions 21, 22. The construction jig 1 according to this embodiment is described in detail below.

Figure 4 is a perspective view showing a construction jig 1 according to this embodiment. The construction jig 1 has a tubular member (engagement member) 10 and an operating member 30. The tubular member 10 and the operating member 30 are both made of, for example, metal and are integrally formed by welding, for example. The tubular member 10 has a circular or approximately rectangular cross section intersecting with the axis x passing through its center. The tubular member 10 has a tubular portion 11 and a closing portion 13. The tubular portion 11 is cylindrical and extends around the axis x. The tubular portion 11 has an opening 12 at one end and is closed at the other end by the closing portion 13.

Two marks M1 and M2 are provided on the closure portion 13 of the tubular member 10. Marks M1 and M2 are located in radially opposing positions across the axis x of the tubular member 10. On the opening 12 side of the tubular member 10, starting ends 21a and 22a of engaging protrusions 21 and 22, described below, are located at positions corresponding to the positions of marks M1 and M2. Note that marks M1 and M2 do not necessarily have to be provided.

Figure 5A is a plan view of the tubular member 10 as seen from the opening side. Figure 5B is a cross-sectional view of the tubular member 10 taken along the axis x. The inner circumferential surface 14 of the tubular member 10 is formed as a circumferential surface. The tubular member 10 has two engaging protrusions 21, 22. The engaging protrusions 21, 22 protrude inward from the inner circumferential surface 14 toward the axis x passing through the center of the tubular member 10. In this embodiment, the engaging protrusions 21, 22 extend spirally around the axis x along the inner circumferential surface from one end of the tubular member 10 to the other end. The starting ends (one end) 21a, 22a on one end of the engaging protrusions 21, 22 are located at the end on the opening 12 side of the tubular member 10, and the ending ends (other end) 21b, 22b on the other end are located on the closing portion 13 side of the tubular member 10.

The starting end 21a of the engaging protrusion 21 and the starting end 22a of the engaging protrusion 22 are positioned opposite each other in the radial direction, and the terminal end 21b of the engaging protrusion 21 and the terminal end 22b of the engaging protrusion 22 are positioned opposite each other in the radial direction. In this embodiment, the angular range Rad between the starting ends 21a, 22a and the terminal ends 21b, 22b of the engaging protrusions 21, 22 is 180°, but the angular range Rad may be at least 90° or greater.

The engaging protrusions 21, 22 have a predetermined thickness, extend along the inner circumferential surface 14, and have radially facing engaging surfaces 21c, 22c. The engaging protrusions 21, 22 engage with the spacer 300, for example, at predetermined locations on the engaging surfaces 21c, 22c that are diagonally aligned with the spacer 300. The width of the engaging protrusions 21, 22 is the same from the starting ends 21a, 22a to the terminal ends 21b, 22b. The inner diameter of the tubular member 10 at the engaging protrusions 21, 22 is set smaller than the diagonal width 300CW (see Figure 3) at any position on the leg portion 320 of the spacer 300 in the height 300H direction.

Figure 6 is a developed view of the inner peripheral surface 14 of the tubular member 10. The height 10H along the axis x of the tubular portion 11 need only be a dimension sufficient to rotate the spacer 300 by at least 90 degrees while the construction jig 1 is in contact with the spacer 300 between the starting ends 21a, 22a and the ending ends 21b, 22b of the engaging protrusions 21, 22. For example, when the starting ends 21a, 22a of the engaging protrusions 21, 22 of the tubular member 10 engage with the spacer 300 and the tubular member 10 is pushed toward the spacer 300 along the axis x to rotate the spacer 300, it is preferable that the tubular member 10 have a height 10H sufficient to rotate the spacer 300 and engage the deck plate 200 before the tubular portion 11 contacts the engaging portion 330 of the spacer 300 at the end on the opening 12 side.

The engaging protrusions 21, 22 extend at a predetermined angle θ relative to the opening edge 12a on the opening 12 side of the engaging member 10 and the closing edge 13a on the closing portion 13 side. The angle θ is in the range of 0°<θ<90°, preferably 35°<θ<80°, and more preferably 50°<θ<60°. The angle θ is determined or limited as appropriate based on the height 10H of the tubular member 10, the angular range Rad over which the engaging protrusions 21, 22 extend, the inner diameter of the engaging protrusions 21, 22, the height 300H of the spacer 300 to be rotated, and the diagonal width 300CW of the spacer 300 at the position where it first engages with the tubular member 10, etc.

The operating member 30 has a rod-shaped extension portion 31 and a grip portion 32. The extension portion 31 is formed, for example, from a metal rod-shaped member. One end of the extension portion 31 is connected to the center of the closure portion 13 of the tubular member 10, for example, by welding. The extension length of the extension portion 31 may be set appropriately, so that, for example, the worker using the construction jig 1 can install the spacer 300 while standing.

The gripping portion 32 is formed, for example, from a rod-shaped member made of metal. The extension direction of the gripping portion 32 is perpendicular to the extension direction of the extension portion 31. The extension portion 31 and the gripping portion 32 are connected to each other to form a T-shape. The other end of the extension portion 31 is connected, for example, by welding, to the approximate center of the gripping portion 32 in the longitudinal direction. The gripping portion 32 is the part that an operator grasps when rotating the spacer 300.

<How to install the spacer>
Next, the method includes the steps of using the construction jig 1 according to this embodiment to temporarily place the spacer 300 on the valley bottom 220, an engagement step of engaging the construction jig 1 with the spacer 300 placed on the valley bottom 220, a rotation step of pushing the construction jig 1 engaged with the spacer 300 toward the deck plate 200 to rotate the spacer 300, and a locking step of locking the spacer 300 to the deck plate 200. A method of installing the spacer 300 on the deck plate 200 will now be described in detail.

Figure 7A shows a spacer 300 temporarily placed on the deck plate 200. Figure 7B is a plan view showing the engagement between the construction jig 1 and the spacer 300 according to this embodiment. The spacer 300 is temporarily placed on the valley bottom 220 of the deck plate 200 so that the pair of legs 320 each face in the longitudinal direction L, for example, so that the opposing edges of the support portions 310 are parallel or approximately parallel to the engagement grooves 242 of the deck plate 200. Multiple spacers 300 are lined up at predetermined intervals along the longitudinal direction L on the valley bottom 220 of the deck plate 200 (temporary installation process).

In this state, the construction jig 1 is brought closer to the spacer 300 from the opening 12 side. In this case, the tubular member 10 is brought closer to the spacer 300 so that the marks M1 and M2 on the tubular member 10 are positioned diagonally across the spacer 300. This causes the engaging protrusions 21 and 22 to diagonally engage (contact) the support portion 310 and leg portion 320 of the spacer 300 at or near the starting ends 21a and 22a (engagement process). For example, the engaging protrusions 21 and 22 engage with the leg portion 320 of the spacer 300 at position P1 (see Figures 6 and 7B) in the direction of height 10H.

Figure 8A shows the process of rotating the spacer 300 using the construction jig 1. Figure 8B shows the spacer 300 rotating. Next, the worker grasps the gripping portion 32 and pushes the tubular member 10 toward the deck plate 200 along the axis x. In this case, the position of the spacer 300 in the direction of height 300H where it contacts the engaging protrusions 21, 22 remains the same or approximately the same, but the position of the engaging protrusions 21, 22 in the direction of height 10H where it contacts the spacer 300 changes from position P1 to position P2 (see Figures 6 and 8B). Accordingly, the spacer 300 is pressed in the same direction by the engaging protrusions 21, 22 at diagonal positions, causing it to rotate along the extension direction of the engaging protrusions 21, 22 (rotation process).

In addition, since the leg portions 320 of the spacer 300 are expanded from top to bottom in the direction of height 300H, contact with the engaging protrusions 21 and 22 causes them to approach each other on the engaging portion 330 side in the direction of height 300H of the spacer 300, and they also elastically return to their original state. This strengthens the engagement between the leg portions 320 and the engaging protrusions 21 and 22. It is preferable to rotate the spacer 300 in a direction in which the other corner 332 leads the rotation direction.

Figure 9A shows the process of using the installation jig 1 to lock the spacer 300 to the deck plate 200. Figure 9B shows the spacer 300 locked to the deck plate 200. By further pushing the tubular member 10 into the spacer 300, the engaging protrusions 21, 22 of the tubular member 10 change the position of contact with the spacer 300 in the direction of height 10H from position P2 to position P3 while maintaining contact (engagement) with the pair of legs 320 of the spacer 300 (see Figures 6B and 9B). The tubular member 10 is pushed in until the engaging portion 330 of the spacer 300 slides into the engaging groove 242 of the deck plate 200.

Finally, the construction jig 1 is pulled up to remove the tubular member 10 from the spacer 300. Because the engagement portion 330 of the spacer 300 is inserted into the engagement groove 242 of the deck plate 200, the tubular member 10 is released from the spacer 300.

With the construction jig 1 described above, the tubular member 10 of the construction jig 1 can be simply pushed into the spacer 300 to rotate the spacer 300 and insert the engagement portion 330 of the spacer 300 into the engagement groove 242 of the deck plate 200, without any direct manual work by the worker. This improves work efficiency and significantly reduces the workload.

Furthermore, the engaging protrusions 21, 22 are located parallel to each other in opposing positions, allowing the spacer 300 to act diagonally, thereby allowing the spacer 300 to rotate stably and reliably.

Furthermore, the engaging protrusions 21, 22 do not overlap with each other between the starting ends 21a, 22a and the ending ends 21b, 22b in the direction of height 10H. This prevents, for example, two engaging protrusions 21, 22 from contacting one leg 320 at different height positions, making it easier to pull out the tubular member 10 from the spacer 300.

Furthermore, the engaging protrusions 21, 22 extend over an angular range Rad of at least 90° on the inner circumferential surface 14 of the tubular member 10, or an angular range Rad of 180° in this embodiment, ensuring sufficient space for rotating the spacer 300 by 90°.

Furthermore, the construction jig 1 is equipped with an operating member 30 having an extension portion 31 that extends vertically from the cylindrical member 10, allowing the worker to handle the construction jig 1 while standing upright without bending over. The grip portion 32 of the operating member 30 also improves operability for the worker.

Furthermore, since the spacer 300 can be approached based on the marks M1 and M2, the engaging protrusions 21 and 22 can be initially engaged with the spacer 300 at or near the respective starting ends 21a and 22a, thereby increasing the distance in the height direction over which the engaging protrusions 21 and 22 engage with the spacer 300.

Furthermore, with the construction jig 1 according to this embodiment, if the end face of the tubular portion 11 on the opening 12 side comes into contact with the engaging portion 330 of the spacer 300 before the engaging portion 330 of the spacer 300 enters the engaging groove 242 of the deck plate 200, the operating member 30 can be rotated to rotate the tubular member 10, thereby allowing the engaging protrusions 21, 22 engaged with the spacer 300 to further rotate the spacer 300.

<Modification>
The construction jigs 1A and 1B according to Modifications 1 and 2 are described below. FIG. 10 is a perspective view of the construction jig 1A according to Modification 1. Note that, below, the same components as those in the construction jig 1 are given the same reference numerals and their description may be omitted. The construction jig 1A according to Modification 1 includes a cylindrical member 10, an operating member 30, and a footplate 40. The footplate 40 is formed, for example, from a steel plate and is attached to the closing portion 13. The footplate 40 is formed rectangular in a plan view and is attached to the closing portion 13 with a portion protruding radially from the cylindrical portion 11. The construction jig 1A can achieve the same effects as the construction jig 1. Furthermore, by stepping on the footplate 40 when rotating the spacer 300 with the construction jig 1A, it becomes easier to press the construction jig 1A into the spacer 300.

Figure 11 is a perspective view of construction jig 1B according to variant 2. Note that, below, the same components as those in construction jig 1 are given the same reference numerals and their description may be omitted. Construction jig 1B according to variant 2 has a tubular member 10B and a step plate 40. The tubular member 10B is open at both ends in the direction of axis x, and the opening on the side opposite opening 12 is closed by the step plate 40. Construction jig 1B can achieve the same effects as construction jigs 1 and 1A.

<Others>
While the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments and variations 1 to 3, and includes all aspects encompassed by the concept of the present invention and the scope of the claims. Furthermore, various configurations may be appropriately and selectively combined to achieve at least some of the above-described problems and advantages. For example, in the above-described embodiments, one end of the tubular member 10 at the height 10H coincides with the terminal ends 21b, 22b of the engaging protrusions 21, 22. However, the tubular portion 11 may have an extension (not shown) extending from the terminal ends 21b, 22b of the engaging protrusions 21, 22 along the axis x toward the side opposite the opening 12. The extension allows the terminal ends 21b, 22b of the engaging protrusions 21, 22 to engage with the spacer 300, even when, for example, they extend beyond the support portion 310 of the spacer 300 toward the engaging portion 330.

In addition, in the above-described embodiments, two engaging protrusions 21, 22 are provided on the inner peripheral surface 14 of the tubular member 10 over an angle range Rad of 180°. However, for example, three engaging protrusions 21, 22 may be provided at equal intervals over an angle range Rad of 120°, or four engaging protrusions 21, 22 may be provided at equal intervals over an angle range Rad of 90°. This increases the number of engagement points between the construction jigs 1, 1A, and 1B and the spacer 300.

In addition, in the above-described embodiment, the tubular member 10 engages with the spacer 300 via the engaging protrusions 21, 22. However, instead of the engaging protrusions 21, 22, for example, a recessed groove may be formed on the inner circumferential surface 14, extending spirally in the circumferential direction. The recessed groove engages, for example, at each corner 300C (see Figure 3) of the spacer 300 and the support portion 310.

1, 1A, 1B... Construction jig 10... Cylindrical member (engagement member)
21, 22...engagement protrusions 30...operation member 40...tread 100...composite slab 200...deck plate, 210...peak portion, 211...groove, 220...valley bottom portion, 230...inclined portion, 240...transition portion, 241...bulge portion, 242...engagement groove (dovetail groove)
300...Spacer

Claims (6)

A construction jig that rotates a spacer that supports reinforcing bars arranged in the longitudinal direction of a deck plate having a wave-shaped configuration in which multiple peaks and valleys that are continuous with each other via inclined portions are connected to each other at the valley bottoms, and installs the spacer on the deck plate,
a cylindrical engaging member having at least one open end that engages with the spacer;
The engaging member is
a circumferential surface as an inner peripheral surface;
At least two engaging portions are formed on the inner circumferential surface so as to engage with the spacer, and extend in a circumferential direction from one end on an opening side that accommodates the spacer to another end on the opposite side;
and
a construction jig, characterized in that the engaging member is moved along an axis in a state in which the engaging portion is engaged with the spacer, thereby rotating the spacer along the engaging portion. The construction jig described in claim 1, characterized in that the engaging portions extend parallel to each other at radially opposing positions. The construction jig according to claim 1 or 2, characterized in that the at least two engaging portions do not overlap with each other in the axial direction of the engaging member, at least excluding one end portion on the one end side and the other end portion on the other end side. The construction jig described in any one of claims 1 to 3, characterized in that the engagement portion extends over an angular range of at least 90° between one end on the one end side and the other end on the other end side. The construction jig described in any one of claims 1 to 4, characterized in that the other end of the engaging member is closed and is provided with an operating member connected to the closed side of the engaging member, which moves the engaging member engaged with the spacer in the axial direction. An installation method for rotating the spacer and installing it on the deck plate using the installation jig according to any one of claims 1 to 5,
a temporary placement step of temporarily placing the spacer at the valley bottom;
an engaging step of engaging the construction jig with a spacer installed at the valley bottom;
a rotating step of pushing the installation jig engaged with the spacer toward the deck plate to rotate the spacer;
a locking step of locking the spacer to the deck plate;
A spacer installation method comprising: