JP2004027506A - Coupling structure of precast concrete floor slab - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coupling structure of a precast concrete floor slab allowing a reinforcement arrangement operation, form assembly, and form releasing operation to be easily performed and the ends of floor slabs to be easily positioned. <P>SOLUTION: Connection reinforcements 3 are projected, in bar shape, from the end face 2 of an opposed floor slab 1 at right angle to each other, main reinforcements 4a and 4b orthogonal to each other are arranged between the connection reinforcements 3, and a reinforced concrete bottom plate 5 having an excellent adhesiveness to deposited concrete 6 is allowed to abut on the opposed both side end faces 2 and fixedly buried. Thus the reinforcement arrangement operation, form assembly, and form releasing operation can be easily performed, and the end faces 2 of the floor slabs 1 can also be easily positioned. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a joint structure of a precast concrete slab.
[0002]
[Prior art]
In the joint structure of precast concrete slabs to be constructed at construction sites, etc., loop-shaped connecting bars project from the end faces of the facing slabs so as to be entangled with each other. In many cases, main reinforcing bars are arranged at right angles, concrete is poured between the end faces where the main reinforcing bars are arranged, and floor slabs are integrated.
[0003]
However, in the joint structure in which the connecting bars are formed in a loop shape, it is necessary to insert the main reinforcing bar between the loops of the connecting bars entangled from the lateral direction. Was.
[0004]
In order to cope with this problem, Japanese Patent Application Laid-Open No. 2000-336820 discloses that connecting bars are projected at right angles in a staggered manner from the end faces of the facing floor slabs, and are perpendicular to the connecting bars protruding from the end faces on both sides. A joint structure in which a main reinforcing bar is arranged from above or below a connecting bar is described.
[0005]
Further, in Japanese Patent Publication No. 3165363, a steel bottom plate as a part of a mold is inserted between lower surfaces of floor slabs whose end faces are opposed to each other in order to facilitate the work of removing the mold. A joint structure is described in which concrete is cast and the bottom plate is integrated with floor slabs on both sides as it is. This joint structure uses a loop-shaped connecting bar.
[0006]
In this joint structure, a bar-like bar is erected on the upper surface of the bottom plate and a loop-like connecting bar is used to secure the jointability of the steel bottom plate, so that the reinforcing work and the formwork There is a problem that assembly work is very difficult. Further, since the bottom plate is inserted between the lower surfaces of the floor slabs, the floor slabs opposed to each other become unstable, and there is a problem that positioning between the end faces becomes difficult.
[0007]
[Problems to be solved by the invention]
Therefore, an object of the present invention is to provide a joint structure of a precast concrete slab in which a reinforcing work, an assembling of a formwork, and an unmolding work can be easily performed and the end faces of the slab can be easily positioned.
[0008]
[Means for Solving the Problems]
In order to solve the above problems, the present invention arranges the end faces of the precast concrete floor slabs facing each other, and arranges the main reinforcing bars orthogonally between connecting bars projecting at right angles in a bar shape from the end faces on both sides, In the joint structure of the precast concrete slab in which the concrete is cast between the end faces on which the main reinforcing bars are arranged, a bottom plate made of reinforced concrete or prestressed concrete is buried by abutting against the bottoms of the opposite end faces of the floor slabs. The configuration was adopted.
[0009]
That is, in order to facilitate the rebar arrangement work and the assembling work of the formwork, the connection rebar is projected from the end face of the opposing floor slab at a right angle in a bar shape, and the main rebar is arranged orthogonally between these connection rebars. In addition, in order to facilitate the work of removing the formwork, a bottom plate made of reinforced concrete or prestressed concrete, which has excellent bondability with the concrete to be cast, is brought into contact with the bottoms of the opposing floor slab end faces. It was buried and the positioning between the end faces of the floor slab was made easy.
[0010]
By forming irregularities in the vertical cross section on the end face of each of the opposed precast concrete slabs, it is possible to increase the shear strength against vertical displacement between the slabs and improve the fatigue durability of the joint structure. it can.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. As shown in FIGS. 1 and 2, the joint structure of the precast concrete slab is such that the end faces 2 of the precast concrete slab 1 are arranged to face each other, and a bar-shaped connecting bar 3 is formed from the end faces 2 on both sides of the precast concrete slab. The main reinforcing bars 4a, 4b are arranged in two rows at right angles to the connecting bars 3 protruding from each end face 2 in two upper and lower stages alternately in a horizontal direction. The bottom plate 5 is abutted against the bottoms of the end surfaces 2 on both sides facing each other, and concrete 6 is cast between the end surfaces 2. Each end surface 2 is formed with wavy irregularities in a vertical cross section. As described later, the upper main reinforcing bar 4a is arranged above the connecting bar 3, and the lower main reinforcing bar 4b is arranged below the connecting bar 3. The concrete 6 is not shown in FIG. 1 so that the inside of the joint structure can be seen.
[0012]
Hereinafter, a procedure for installing the above-described joint structure will be described. First, the bottom plate 5 is disposed at a predetermined base position where the joint structure is to be constructed, and the two lower main reinforcing bars 4b are placed on the bottom plate 5. Next, the bottom of the end face 2 of each floor slab 1 is placed on both sides of the bottom plate 5 so as to face each other, and the main reinforcing bar 4b placed on the bottom plate 5 is arranged below the connecting bar 3 on the lower stage. The main reinforcing bar 4a is arranged above the upper connecting bar 3.
[0013]
Thereafter, the formwork is assembled on the side surface between the two end faces 2 and the concrete 6 is poured into the formwork, thereby filling the bottom plate 5 and integrating the two floor slabs 1. Finally, remove the side mold.
[0014]
In the above embodiment, the bottom plate is made of reinforced concrete, but may be made of prestressed concrete. Further, the unevenness of the end surface of the floor slab is not limited to the corrugated one as in the embodiment, but may be any as long as the unevenness is formed in a vertical cross section. The main reinforcing bars can be arranged in three or more steps in the thickness direction of the floor slab.
[0015]
【The invention's effect】
As described above, in the joint structure of the precast concrete slab of the present invention, connecting bars are projected at right angles in a bar shape from the end faces of the facing slabs, and the main reinforcing bars are arranged orthogonally between these connecting bars. At the same time, the bottom plate made of reinforced concrete or prestressed concrete, which has excellent bonding properties with the concrete to be cast, was buried by butt burying it against the bottom of the end faces of the opposing floor slabs. In addition, it is possible to easily perform the demolding operation, and to easily position the end faces of the floor slab.
[0016]
Further, by forming unevenness in a vertical cross section on the end face of each of the opposed precast concrete slabs, the shear strength against vertical displacement between the slabs is increased, and the fatigue durability of the joint structure is improved. be able to.
[Brief description of the drawings]
FIG. 1 is an external perspective view showing an embodiment of a joint structure of a precast concrete slab. FIG. 2 is a longitudinal sectional view of the joint structure of FIG.
1 floor slab 2 end face 3 connecting bar 4a, 4b main reinforcing bar 5 bottom plate 6 concrete

Claims (2)

The end faces of the precast concrete slabs are opposed to each other, and the main reinforcing bars are arranged orthogonally between connecting bars projecting from the end faces on both sides at right angles in a bar shape, and concrete is struck between the end faces where the main reinforcing bars are arranged. In the joint structure of the precast concrete slab, the joint structure of the precast concrete slab is characterized in that a bottom plate made of reinforced concrete or prestressed concrete is buried by abutting against the bottoms of the end faces of the opposite side slabs. . The joint structure of a precast concrete slab according to claim 1, wherein unevenness in a vertical section is formed on an end face of each of the opposing precast concrete slabs.

Images