JP2000282610A - Half precast floor slab and joint structure for half precast floor slab - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily and efficiently joint half precast floor slabs. SOLUTION: A first loop shaped joint bar 10 is provided on an end part of a half precast floor slab 1 of the downside. A reinforcing bar passing port 13 that allows passage of reinforcing bars 16 is opened in the joint bar 10. A second loop typed joint bar 11 is provided on an end part of a half precast floor slab 1 of the upside, and reinforcing bars 16 are beforehand provided in the second loop shaped joint bar 11. When the second loop shaped joint bar 11 is descended to the first loop shaped reinforcing bar 10, reinforcing bars 16 go into the inside of the second loop shaped joint bar 11 from the reinforcing bar passing port 13 of the first loop shaped joint bar 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a half precast slab and a joining structure of the half precast slab.

[0002]

2. Description of the Related Art For example, when forming a bridge such as a road bridge, a full precast slab into which a prestress is introduced is often used. As shown in FIG.
The full precast floor slabs 101 are arranged on the bridge girder 100 so as to be spread from the upper right to the lower left in the drawing.

Further, a pair of full precast floor slabs 101
As shown in FIG. 8, a plurality of loop-type joint bars 102A and 102B project from the full precast floor slabs 101A and 101B at predetermined intervals on the side surface where A and 101B are joined. The loop joint 102 is
Both ends have a closed U-loop shape embedded in the full precast floor slab 101. When the two full precast slabs 101A and 101B are joined, the loop type joint bar 102A becomes the other full precast slab 101B.
Are arranged alternately between the loop-type joint bars 102B protruding from the upper surface.

[0004] Then, loop-type joint bars 102A, 102
In the loop 104 formed when B is superimposed in the direction of the bridge girder 100, the reinforcing bar 103 is inserted in the lateral direction (the bridge girder 100).
(In a direction perpendicular to the direction) (see FIG. 9). As described above, the work of inserting the reinforcing bars 103 from the lateral direction is a work at a site where it is difficult to sufficiently secure a high place or a scaffold, so that the work efficiency is extremely low.

To solve this problem, Japanese Patent Application Laid-Open No.
No. 252015 discloses a joint structure shown in FIGS. 10 and 11. This half precast floor slab 108
Are provided with large curvature loop joints 105 or small curvature loop joints 106 having different curvatures. The lower ends of the loop-type joint bars 105 and 106 are embedded in the half precast floor slab 108, while the upper edges thereof are both open, and have a substantially J-shape as a whole. When the adjacent half precast floor slab 108 is assembled at a predetermined position, the large curvature and small curvature loop joints 105 and 106 are arranged at positions where they overlap each other. At this time, each loop-type joint bar 105, 106
Is not completely closed annular, and the leading edge 105 </ b> A of the large curvature loop joint 105 is formed.
A reinforcing bar insertion opening 107 is opened between the joint and the small curvature loop joint bar 106.

[0006] According to this structure, the reinforcing bars 103 can be assembled from above in a state where the adjacent half precast floor slabs 108 are assembled. Efficiency can be improved.

[0007]

However, also in the above example, the reinforcing bars 103 are connected to the loop-type joint bars 105,
The work of inserting the half precast floor slabs 108 in the interior of the interior of the 106 has to be performed at the site where the half precast slabs 108 are arranged side by side, and there is still room for improvement. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a half precast slab and a joining structure of a half precast slab that can be easily and efficiently joined.

[0008]

Means for Solving the Problems In order to solve the above-mentioned problems, a half precast slab according to the first aspect of the present invention comprises:
A half-precast slab in which both half-precast slabs are placed side by side by hanging the half-precast slab adjacent to the pre-installed half-precast slab from above, and both side edges are joined to each other. In a pair of side surfaces to be joined, a plurality of first loop-type joint bars are provided on one side surface, and a plurality of second loop-type joint bars are provided on the other side surface. When a plurality of the half precast floor slabs are arranged side by side in the longitudinal direction at intervals, the first
The second loop-type joint of the other half precast slab is located between the loop-type joints of
And a half precast floor slab in which reinforcing bars are arranged so as to penetrate the loop formed by the second loop-shaped connecting bars in the longitudinal direction of the side surface, wherein the second loop-shaped connecting bars have the reinforcement in advance. The streaks are held in a state of penetrating the loop, and the first loop-type joint streak is opened at one end, and when the work of suspending the two half precast slabs is performed, the second loop joint stitch is held. It is characterized in that a reinforcing bar passage is formed to allow the reinforcing bar held by the type joint bar to enter.

According to a second aspect of the present invention, in the first aspect, an insertion for inserting the reinforcing muscle into the second loop-type joint muscle is provided in the second loop-type joint muscle. The opening for use is open. The invention according to claim 3 is the one according to claim 1 or 2, wherein one side surface of the half precast floor slab includes:
The first loop joint bar is provided, and on the other side surface,
It is characterized by comprising the second loop type joint bar.

According to a fourth aspect of the present invention, there is provided a joint structure for a half precast slab, wherein the two half precast slabs are placed side by side by suspending the half precast slab adjacent to the previously installed half precast slab. And a structure in which both side edges are joined to each other, and a pair of first loop-type joint bars are provided on one side surface of a pair of side surfaces to which the two half precast floor slabs are connected. However, on the other side, a plurality of second loop-type joint bars are arranged at intervals in the longitudinal direction of each side, and when a plurality of the half precast floor slabs are arranged side by side, The second loop joint of the mating half-precast slab is located between the first loop joints and within the loop formed by the first and second loop joints. A reinforcing bar is provided so as to penetrate in the longitudinal direction of the side surface, and the reinforcing bar is held in the second loop-type joint bar in a state where the reinforcing bar has passed through a loop in advance, and the first loop-type connecting bar is provided. One end of the joint bar is opened, and when the work of suspending the two half precast slabs is performed, a reinforcing bar passage opening for allowing the reinforcing bar held by the second loop type joint bar to enter is provided. It is characterized by being formed.

[0011]

According to the first or fourth aspect of the present invention, the reinforcement is held in advance by the second loop-type joint bar, and the adjacent half precast floor slab is suspended. Do the work. The operation of holding the reinforcing bars in the second loop-type joint bars is performed, for example, at a factory for manufacturing a half precast floor slab or at a ground portion in an elevated area where suspension work is performed. And it can operate safely. The first loop type joint bar provided on the other half precast floor slab includes:
Since the reinforcing-bar passage is formed, if the half-precast floor slab is lowered in a state where the reinforcing bar is held by the second loop-type connecting bar, the reinforcing bar enters the first and second loop-type connecting bars. You can enter. For this reason, at the site where the half precast floor slab is suspended, the work of inserting the reinforcing bars into the loop is performed at the same time as the completion of the suspension work, so that efficient work can be performed.

According to the second aspect of the present invention, when a reinforcing bar is previously attached to the second loop-type joint bar, the reinforcing bar can be inserted from the insertion opening, so that the operation is facilitated. This means
Not only is it effective when the cross section of the half precast slab is flat, the cross section of the half precast slab is irregularly shaped or arched with curvature,
This is particularly effective when it is not possible to insert reinforcing bars from the lateral direction.

According to the third aspect of the present invention, the two half precast slabs can be arranged side by side by continuously suspending and hanging the adjacent half precast slabs. I can do it. On the other hand, when the same type of loop joint is provided on both sides of one half precast slab, first, one half precast slab having the loop joint on one side is provided. It is necessary to insert a half precast floor slab in which the other loop type joint bar is provided between them, and the work process becomes complicated.

[0014]

Next, an embodiment of the present invention will be described in detail with reference to FIGS. FIG.
Is a slab 2 provided with a half precast slab 1
(The floor slab 2 is laid in the front and back directions on the paper surface). The floor slab 2 has a pair of left and right box girders 3
(Note that three or more box girders 3 may be provided depending on conditions such as the width of the floor slab 2). The box girder 3 is provided along the direction in which the floor slab 2 extends, and an upper opening 4 is provided at the upper center thereof along the length direction of the box girder 3.
Is open. The half precast floor slab 1 is provided so as to close the upper opening 4.

FIG. 2 shows a state in which the half precast floor slab 1 is mounted on the upper surface of the box girder 3. A plurality of rows of studs 5 are provided on a pair of upper surfaces 3A on the left and right sides of the upper opening 4 of the box girder 3 at predetermined intervals. The half precast floor slab 1 is assembled by using a row of studs 5 closest to the upper opening 4 among these studs 5.

As shown in FIG. 2, the half precast slab 1 has a concrete portion 7 and a long side direction (the left-right direction in FIG. 3) on the upper surface of the concrete portion 7.
Four rows of truss bars 8 projecting at predetermined intervals along
A main bar 9 in the direction perpendicular to the bridge axis projecting from both side edges of the long side at a predetermined interval (in the construction site of the half precast slab 1 of the present embodiment, After assembling 1 side by side, concrete is cast in place from above). The short side direction of the concrete portion 7 is formed so as to draw an arch shape which is bent upward. In addition, mounting holes 6 are provided at both side edges in the short side direction of the half precast floor slab 1 so as to allow the studs 5 to pass therethrough in accordance with the intervals of the studs 5.

Next, a structure for joining the half precast slabs 1 will be described with reference to FIG. FIG.
A pair of loop-type joint bars 10, 11 protrude from both left and right end portions 7A, 7B. The two loop-type joint bars 10, 11 are formed in a substantially J-shape by bending both end portions of one joint bar 12 upward. The edge of the first loop-type joint bar 10 on the left side in the figure is opened upward, and a reinforcing bar passage 13 is provided here. Similarly, the edge of the second loop-type joint bar 11 is also opened upward, and an insertion opening 14 is provided here.

First and second loop-type joint bars 10, 11
Projecting heights are substantially equal to each other.
On the other hand, the folded length of the second loop-shaped joint bar 11 (from the center of the loop of the second loop-shaped joint bar 11 (hereinafter, referred to as the “most protruding portion 11A”) to the edge where the insertion opening 14 is provided). The length of the loop of the first loop-type joint 10 (the center of the loop of the first loop-type joint 10 (hereinafter, referred to as the length)
(The length from the “most protruding portion 10A”) to the edge where the reinforcing bar passage opening 13 is provided).
Below the first loop-type joint bar 10, the concrete portion 7 extends to a position projecting slightly longer than the most protruding portion 10A to be a first end portion 7A. On the other hand, below the second loop-type joint bar 11, the concrete portion 7 is terminated at substantially the same position as the edge where the insertion opening 14 is provided to form a second end 7B.

Adjacent half precast floor slabs 1 are assembled side by side with a first loop-type joint bar 10 and side surfaces with a second loop-type joint bar 11 and are placed side by side. Thus, the first and second ends 7A, 7B
When the pair of half precast floor slabs 1 are aligned side by side so as to align with each other, the most protruding portion 10A of the first loop type joint bar 10 and the second loop type joint bar 11
Is arranged at a position where the edge of the insertion opening 14 substantially matches. On the other hand, the second loop-type joint bar 11
The most protruding portion 11A is located outside (to the right in FIG. 4) the edge of the reinforcing bar passage 13 of the first loop-type joint bar 10, and the second loop-type joint bar 11
A predetermined gap is provided between the reinforcing bar passage 13 and the reinforcing bar passage 13.

The adjacent half precast slab 1
Are arranged side by side, the first and second loop-type joint bars 10 and 11 form a loop 15 having a closed annular cross section. Inside this loop 15,
A plurality of reinforcing bars 16 are provided. The reinforcing bar 16 has substantially the same shape as the main bar 9 in the direction perpendicular to the bridge axis.
The center of 6 has an arch shape corresponding to the arch shape of the concrete portion 7, and both end portions protrude from the concrete portion 7 so as to be fixed by a predetermined length.

Although not described in detail, the half precast floor slab 1 is prepared in two types in which the joint bars 12 are displaced in the short side direction. By arranging these two types of half precast floor slabs 1 alternately side by side, the second loop joint bar 11 is located between the first loop joint bars 10.

Next, the procedure of the hanging work for assembling the half precast floor slabs 1 configured as described above in a side-by-side state will be described. First, the second loop joint bar 1
An operation of inserting the reinforcing bar 16 inside the inside of the unit 1 is performed. This work is performed, for example, at a factory where the half precast slab 1 is manufactured, or at a ground part at an elevated site where the half precast slabs 1 are suspended side by side.
The work can be performed in a safe place with few restrictions on the place (of course, this work can also be performed at the site where the work of suspending the half precast floor slab 1 is performed). At this time, the reinforcing bars 16 are inserted from above the half precast floor slab 1 by using the insertion openings 14 of the second loop-type joint bars 11.

In the state where the reinforcing bars 16 are temporarily held by the second loop-type joint bars 11, the first loop-type joint bars 10 are exposed and the half precast floor slab at the lower right side in FIG. 4 is exposed. 1, the half precast floor slab 1 on the upper left side is lowered from above. At this time, the studs 5 of the box girder 3 are passed through the mounting holes 6 of the half precast floor slab 1 so that the half precast floor slab 1 is positioned with respect to the box girder 3.

When the two half precast slabs 1 are assembled so that the first end 7A and the second end 7B are aligned,
The most protruding portion 11 </ b> A of the second loop-type joint bar 11 is located at a more distal end than the edge of the reinforcing bar passage 13 of the first loop-type joint bar 10. In this manner, the reinforcing bars 16 temporarily held by the second loop-type connecting bars 11 are inserted into the first loop-type connecting bars 10 through the reinforcing-bar passage 13 and the reinforcing bars 16 and the first loop-type connecting bars. The joint bar 10 is smoothly assembled inside the loop 15 without abutting. After the reinforcing bars 16 have entered the inside of the loop 15 in this way, the reinforcing bars 16 are arranged at predetermined positions, and a concrete driving operation is performed.

As described above, according to the present embodiment, the second
Holding the reinforcing bar 16 in the loop-type joint bar 11 of
The work of suspending the adjacent half precast floor slab 1 is performed. The first loop-type joint bar 10 provided on the mating half precast floor slab 1 is provided with the reinforcing bar passage 13 so that the second loop-type joint bar 11 holds the reinforcing bar 16. When the half precast floor slab 1 is lowered in this state, the reinforcing bars 16 can enter the loop 15 formed by the first and second loop joint bars 10 and 11. For this reason, at the assembly site of the half precast slab 1, the work of inserting the reinforcing bar 16 into the loop 15 can be easily performed, and efficient work can be performed. In particular, the operation of holding the reinforcing bars in the second loop-type joint bars is performed, for example, at a factory for manufacturing a half-precast slab or at the ground portion of an erection site, so that there are few restrictions on places and safe. Work.

Further, even when the cross section of the half precast slab 1 is complicated such as a stepped or arched shape, the joint portion of the adjacent half precast slab 1 can be reinforced. In addition, the second loop-type joint bar 11
Is provided with the insertion opening 14, so that the operation when assembling the reinforcing bars 16 to the second loop-type joint bars 11 in advance becomes easy. This is not only effective when the cross section of the half precast slab 1 is flat, but also the cross section of the half precast slab has an irregular shape or an arched shape with a curvature, and is viewed from the lateral direction. This is particularly effective when it is not possible to insert the reinforcing bars 16 of the above.

Further, the half precast floor slab 1 of the present embodiment has a first loop-type joint bar 10 on one side surface.
However, since the second loop-type joint bar 11 is provided on the other side, the two half precast slabs 1 are arranged side by side by continuously suspending and working the adjacent half precast slabs 1. Work can be performed smoothly. On the other hand, when the same type of loop joint is provided on both sides of one half precast slab, first, one half precast slab having one loop joint is provided. It is necessary to insert a half precast floor slab in which the other side of the loop type joint bar is provided between them, and the work process becomes complicated.

The first and second loop-type joint bars 10 and 11 of the present embodiment are formed in a loop shape with substantially the same curvature, and are formed by the two loop-type joint bars 10 and 11. Loop 15 is a closed loop. For this reason, all the reinforcing bars 16 are arranged inside the loop 15, and the connection at the connection portion of the half precast floor slab 1 is sufficiently reinforced.

<Other Embodiment> FIG. 6 shows another embodiment. In the description of the other embodiments, components having the same functions as those of the above-described embodiments will be denoted by the same reference numerals, and description thereof will be omitted. In FIG. 6, in addition to the upper opening 4 of the box girder 3, the adjacent box girder 3 and the box girder 3 are connected to each other with the half precast floor slab 20, and the half of the floor slab 2 is located at both ends of the box girder 3. The structure in which the precast floor slab 21 is provided is shown. Even in this case, the same operation and effect as the above embodiment can be obtained.

<Reference Example> Although the present invention relates to a half precast slab, the application of a full precast slab will be described. If a sufficient overlap margin for joining the reinforcement passage of the J-shaped loop joint with the loop to be provided is secured,
(1) It is essentially equivalent to the present invention, (2) can achieve the object of the present invention, and has the same function and effect,
(3) It can be said that those skilled in the art can easily conceive of replacing a half precast slab with a full precast slab.

The present invention is not limited to the above-described embodiment. For example, the following ones are also included in the technical scope of the present invention. (1) In the present embodiment, the first and second loop-type joint bars are configured as a part of a circle. The shape may be bent. (2) In the present embodiment, the half precast floor slab is provided with the first loop-type joint bar on one side and the second loop-type joint bar on the other side. According to this, a half precast slab having the first loop-type joint bars on both side surfaces and a half precast slab having the second loop-type joint bars at both ends may be staggered. (3) In the present embodiment, only the joint structure in the floor slab 2 is shown. However, according to the present invention, the present invention can be applied to general building construction and the like.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a road using a half precast slab according to the present embodiment.

FIG. 2 is a perspective view showing a state in which an upper opening of a box girder is closed by a half precast floor slab.

FIG. 3 is a sectional view taken along line AA in FIG. 2;

FIG. 4 is a side cross-sectional view showing a state of suspending work of an adjacent half precast slab.

FIG. 5 is a partial side sectional view after adjoining half precast slabs;

FIG. 6 is a sectional view of a road in another embodiment.

FIG. 7 is a perspective view showing a state in which a half precast floor slab is suspended in a conventional example.

FIG. 8 is a side sectional view showing a state of suspending work of an adjacent half precast slab in a conventional example.

FIG. 9 is a side cross-sectional view of an adjacent half precast floor slab when the hanging operation is completed in the conventional example.

FIG. 10 is a side sectional view showing a state in which half precast floor slabs are adjacently joined in a conventional example.

FIG. 11 is a cross-sectional side view showing a joining mode of adjacent half precast slabs in a conventional example.

[Explanation of symbols]

 1, 20, 21 ... half precast floor slab 10 ... first loop type joint bar 11 ... second loop type joint bar 13 ... reinforcing bar passage 14 ... insertion opening 15 ... loop 16 ... reinforcing bar

Continuation of the front page (71) Applicant 000228350 Nippon Kaiser Co., Ltd. 3-157-7 Higashi, Shibuya-ku, Tokyo (72) Inventor Yoshinobu Nakajima 10th Shionagicho, Minato-ku, Nagoya-shi, Aichi Tokai Concrete Industry Co., Ltd. (72) Inventor Tadashi Uehara 15-18 Nihonbashi Kodenma-cho, Chuo-ku, Tokyo F-term in Miyaji Iron Works Co., Ltd. AG60 BA07 BA33 BA34 BE10 CA83 EA33

Claims (4)

[Claims] 1. A half precast slab adjacent to a pre-installed half precast slab is lowered from above so that both half precast slabs are placed side by side, and their side edges are joined to each other. A half precast floor slab, wherein a plurality of first loop joints are provided on one side and a plurality of second loop joints are provided on the other side. The streaks are arranged at intervals in the longitudinal direction of the side surfaces, and when a plurality of the half precast slabs are placed side by side, the mating half precast slabs are placed between the first loop-type joint bars. A half in which the second loop joint is located, and reinforcing bars are arranged so as to penetrate the loop formed by the first and second loop joints in the longitudinal direction of the side surface; In the recast floor slab, the reinforcing member is held in advance in the second loop-type joint bar in a state of penetrating the loop, and the first loop-type joint bar is open at one end, and the two half precast bars are closed. A half precast slab, wherein a reinforcement passage is formed to allow entry of the reinforcement held by the second loop-type joint bar when the floor slab is suspended. . 2. The apparatus according to claim 1, wherein the second loop-type joint has an insertion opening for inserting the reinforcement into the second loop-type joint. The described half precast floor slab. 3. The half precast floor slab is provided with the first loop type joint bar on one side surface, and the second loop type joint bar on the other side surface. The half precast floor slab according to any one of claims 1 and 2. 4. A method in which both half precast slabs are placed side by side by a hanging operation of lowering a half precast slab adjacent to a pre-installed half precast slab from above, and when both side edges are joined to each other. A pair of side surfaces to which the two half precast floor slabs are connected, a plurality of first loop-type joint bars are provided on one side surface, and a plurality of second loop joint bars are provided on the other side surface. When the loop-type joint bars are arranged at intervals in the longitudinal direction of the side surfaces, and when the plurality of half-precast slabs are placed side by side, the other half-precast member is placed between the first loop-type joint bars. The second loop joint of the floor slab is located;
Reinforcing bars are arranged so as to penetrate the loop formed by the first and second loop-type connecting bars in the longitudinal direction of the side surface, and the second loop-type connecting bars are provided with the reinforcing members in advance. The streaks are held in a state penetrating the loop, and the first loop-type joint streak is open at one end, and when the work of suspending both half precast floor slabs is performed, the second loop joint stitches are held. A joint structure for a half precast floor slab, wherein a reinforcing bar passage is formed to allow the reinforcing bars held by the type joint bar to enter.