JP2000248614A - Structure of connection of precast concrete wall construction building - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an easy-to-separate and demolish connection in a demolishable precast concrete wall construction building. SOLUTION: The structure of connections of a precast concrete wall construction building where precast reinforced concrete panels to form bearing walls 2, 4, 5,... and floor boards 3 and 6 are manufactured in advance, connecting steel plates 11 and 31 mounted in the connections of the panels are connected in a site, and the field connections are embedded in the panels by mortar filling. There the connecting steel plates 11 and 31 are fastened by tightening high strength bolts, and at least high strength bolt and nut portions are covered with synthetic resin covering layers. The connecting steel plates where the covering layers are formed are embedded in the panels by mortal filling.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joint structure of a wall-type precast concrete building, and particularly to a case where a building assembled with large-scale precast reinforced concrete panels is dismantled for relocation or the like, the joint is easily separated. The present invention relates to a joint structure of a wall-type precast concrete building made possible.

[0002]

2. Description of the Related Art In a middle-rise precast concrete building having a conventional wall structure (generally, about 5 stories),
Precast concrete panels are used for load-bearing walls and floor slabs, which are structural elements. For such joining, a so-called dry joint, which is a so-called dry joint, is used to weld an attached steel plate to a vertical metal bar or a welded steel plate, or a sleeve joint for connecting rebars with a sleeve. These joints are designed so as to have a strength against a horizontal load such as an earthquake received by the structure, and are firmly joined in the construction so that the strength of the load-bearing wall body is sufficiently maintained.

[0003]

However, since this type of precast concrete building is not premised on relocation, when building and assembling precast concrete panels by on-site joining, the joints once joined are separated. It never happened. However, there has been a demand to use precast concrete buildings, which can shorten the construction process, as removable houses.

As described above, when the precast concrete panel is to be relocated, each precast concrete panel can be relatively easily regenerated by repairing the surface or the like, but the joint between the panels is cut off by cutting the welded portion. There was only separation means. For this reason, the dismantling of the existing building is troublesome, and the cut pieces of hardware and the like cannot be reused, and incidental work such as mounting another piece of hardware has occurred. As described above, it was impossible to reuse the precast concrete panel only by cleaning the panel surface and the joint.

Accordingly, an object of the present invention is to solve the above-mentioned problems of the prior art, and to provide a structure having sufficient structural strength at a joint portion of a large-sized precast concrete panel and capable of being quickly separated at the time of disassembly. An object of the present invention is to provide a joint structure of a wall-type precast concrete building having:

[0006]

In order to achieve the above-mentioned object, according to the present invention, a precast reinforced concrete panel constituting a load-bearing wall and a floor slab is manufactured in advance, and a joint attached to a joint of the precast reinforced concrete panel is provided. In a joint structure of a wall-type precast concrete building to be assembled on site, the steel sheets are joined together on site and the joints are buried in a panel by mortar filling. At least the high-strength bolts and nuts are covered with a synthetic resin coating layer, and the bonded steel sheet on which the coating layer is formed is embedded in the panel by the mortar filling.

[0007] The through-hole formed in the floor slab through which the joint steel plate connecting the load bearing walls of the upper and lower floors sandwiches the floor slab,
It is preferable that the floor slab has a tapered shape in which the lower side is wider than the upper side.

It is preferable that the synthetic resin coating layer is a coating film of a synthetic resin paint. Alternatively, the synthetic resin coating layer is preferably a synthetic resin adhesive sheet.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the joint structure of a wall type precast concrete building according to the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a perspective view showing an assembled state of precast concrete panels on an intermediate floor of a wall-type precast concrete building 1 assembled using the joint structure of the present invention. FIG. 1 shows several joining directions and joining types. That is, a vertical joint 10 (vertical joint, cross joint) for joining adjacent load-bearing walls 2 on the same floor, and a horizontal joint 20 (horizontal joint, jointing adjacent floor slabs 6 on the same floor).
A horizontal joint 30 (flat joint, cross joint) for joining the load bearing walls 2 and 7 of the upper and lower floors is shown as a representative example.

FIG. 1 shows a slab 3 constituting a slab of a certain floor.
And a plurality of load-bearing walls 2, 4, standing on the floor slab 3,
5, a floor slab 6 constituting an upper floor, and a load-bearing wall 7 of an upper floor erected on the floor slab 6 before being joined.

On the side end faces of the load bearing walls 2, 4, 5 shown in FIG.
1 are buried in three places of upper and lower ends and an intermediate height. The joined steel plate 11 is formed by integrating a part thereof and an anchor bar (not shown) attached to the steel plate, and the anchor bar portion is buried in the concrete panel at the time of panel production. Further, on the upper surface of the load-bearing wall 2, a bonded steel plate 31 is attached which is connected to a lower end of the load-bearing wall 7 built at the same position on the upper floor. Anchor bars attached to a part of the joining steel plate 31 are also buried in the concrete panel. The vertical joint 10 joins the load-bearing walls 2, 2 as adjacent outer walls in a straight line, and forms a cross-joining portion that simultaneously joins the load-bearing walls 4 as inner walls, which are orthogonal to each other.

On the other hand, the floor slabs 6 on the upper floor, which are arranged adjacent to each other,
6 is planarly joined by two horizontal joints 30 in the present embodiment. In the horizontal joint 30, a notch 22 formed in a part of a panel having a configuration described later is formed.
A joint steel plate is housed in the joint steel plate, and the joint steel plate and the attached steel plate are integrally joined (see FIG. 3). Furthermore, the upper end of the joint steel plate 31 that joins the upper floor and the load-bearing walls 2 and 7 on the lower floor projects into the through hole 32 formed in the floor slab 6.

Hereinafter, the structure of each joint will be described with reference to FIGS. FIG. 2A is an enlarged plan view of the vertical joint 10 shown in FIG. As shown in the drawing, a bolt connection via a joint plate 12 is used for connection with the inner wall 4 orthogonal to the bearing wall 2 as the outer wall. An off-the-shelf CT steel plate can be used for the joint plate 12. When the length of the web on the orthogonal side is not enough, the joint plate 1 having a size adapted to the joint shape is used.
It is preferable to manufacture and use 2.

A high-strength bolt 13 is used for bolt connection. Even when the high-strength bolt 13 is used, the bolt strength is designed so that the horizontal load strength at the joint is maintained. It is an important advantage that the use of the bolt joint improves the workability at the time of assembling the panel and facilitates the removal at the time of disassembly. In order to achieve this effect, a covering layer 14 covering the bolt head is formed. The coating layer 14 needs to have resistance (alkali resistance) to the mortar 15 to be filled later, and it is necessary that the filling mortar 15 can form a thick film that does not peel off the film. As shown in FIGS. 2A and 2B, it is preferable that the coating layer 14 covers at least a part of the joined steel plate with the bolt and nut heads at the center. This can prevent the filling mortar 15 from adhering to the bolts and nuts.

In this embodiment, the coating layer 14 is formed by applying a thick coating of a vinyl chloride resin to a predetermined coating thickness. In addition, an epoxy resin coating, a styrene resin coating, or the like can be directly brush-coated or spray-coated. Further, the bolt head may be covered by spraying a polyester resin and a short glass fiber, or a foamed polystyrene-based material may be sprayed. Further, rubber-based fillers such as natural rubber, natural rubber derivatives, butadiene-based synthetic rubber and olefin-based synthetic rubber, and thermoplastic elastomers can be applied. In addition, a synthetic resin sheet having an adhesive surface may be attached to the bolt head to cover it. The adhesive surface may be formed in advance on a sheet and protected with a release paper or the like, or may be used after applying an adhesive.

Further, a formwork surrounding the joint portion is assembled in a state where the bolt bonding and the coating layer are formed, and mortar filling is performed. Although the mortar 15 does not bear the proof stress like the conventional dry joint, the filling is surely performed to close the joint space.

FIG. 3A is an enlarged partial plan view of the horizontal joint 20 shown in FIG. As shown in the figure, a notch 22 having a trapezoidal shape in plan view
And a joint steel plate 21 that fits within the notch 22. In this joint 20, when the floor slab 6 is placed at a predetermined position on the upper end surface of the load-bearing wall 2 on the lower floor and the adjacent floor slabs 6 are arranged, the notches 22 face each other. The joining steel plates 21 at the opposing positions are joined by a high-strength bolt 23 via a joint plate 26. Also in this case, similarly to the vertical joint 10, the covering layer 24 covering the bolt head on the joint plate 26 is formed, and the notch 2 is formed.
2 is filled with a mortar 25 (see FIG. 3B).

FIGS. 4 to 6 show through holes 3 formed in the floor slab 6.
2 and 3 are a plan view and a sectional view showing a structure in which the load-bearing walls 2 and 7 of the upper and lower floors are integrally joined using the through hole 32 and the through-hole 32. FIG.
The floor slab 6, a part of which is not shown, has three load-bearing walls 2 so that the balcony portion at one end has a cantilever structure.
It is supported on the upper end surfaces of two and five. At this time, two joining steel plates 31 are provided on the upper end surface of the load-bearing wall. When the floor slab 6 is placed on the load-bearing wall 2, the upper portion of the joint steel plate 31 projects from the two through holes 32 of the floor slab 6 by a predetermined amount.

The through holes 32 formed in the floor slab 6 are shown in FIG.
As shown in the enlarged view, the lower surface side is wider than the upper surface side of the floor slab and has a trapezoidal tapered shape when viewed from the side. After being joined with the joining steel plate 36 as a metal fitting attached to the lower end portion of the upper floor bearing wall 7 and the high strength bolt 33,
The mortar 35a in the through hole 32 is filled. The tapered dowel is formed to resist the horizontal load acting on the floor slab 6, and the floor slab 6 and the lower bearing wall 2 are dismantled during dismantling.
And can be easily separated.

The notch of the upper floor bearing wall 7 is later replaced with a mortar 35b.
Filled with. At this time, it is preferable that a sheet or the like made of a synthetic resin is adhered to the heads of the bolts and nuts as the coating layer 34 in close contact with the heads.

By constructing a building using such joints 10, 20, 30 in a wall-type precast concrete building, when the building is demolished, mortars 15, 25, 35 covering the joints can be crushed. The high-strength bolts (nuts) 13, 23, and 33 that have been blocked from the mortars 15, 25, and 35 by the coating layers 14, 24, and 34 can be easily exposed. Further, since solidified mortar does not adhere to the exposed high-strength bolts (nuts) 13, 23, and 33, the bolts can be easily removed by applying a predetermined torque. Also, the joint steel plate 3 of the floor slab 6
Since the joining steel plate 31 of the bearing wall 6 and the load-bearing wall 2 are integrated via a tapered dowel, when the floor slab 6 is pulled up by a heavy machine or the like during dismantling, the mortar 35a is detached along the tapered shape. Damage to the concrete portion around the through hole 32 of No. 6 can be minimized.

[0022]

As described above, by employing the above-described structure for joining each large panel of a wall-type precast concrete building, sufficient joint strength is maintained and each joint is removed when the building is dismantled. Can be separated easily and without damaging each part, so that the effect of reusing the panel is significantly improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of a joint structure of a wall-type precast concrete building according to the present invention.

FIG. 2 is a plan sectional view and a side sectional view showing an embodiment of a vertical joint having a joint structure of load-bearing walls according to the present invention.

FIG. 3 is a plan view and a side sectional view showing an embodiment of a horizontal joint having a joint structure of a floor slab according to the present invention.

FIG. 4 is a plan view showing an embodiment of the horizontal joint having a joint structure of the upper and lower floor bearing walls at the floor slab position according to the present invention.

FIG. 5 is a cross-sectional view showing one embodiment of the horizontal joint of the joint structure of the upper and lower floor bearing walls at the floor slab position according to the present invention.

FIG. 6 is a partial cross-sectional view showing an enlarged joint portion in the cross-sectional view shown in FIG. 5;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Wall type precast concrete building 2,4,5,7 Bearing wall 3,6 Floor slab 10 Vertical joint 20,30 Horizontal joint 11,21,31,36 Joint steel plate 12,26 Joint plate 13,23,33 High strength Bolts 14, 24, 34 Coating layer 15, 25, 35, 35a, 35b Mortar 22 Notch 32 Through hole

Claims (4)

[Claims] 1. A precast reinforced concrete panel constituting a load-bearing wall and a floor slab is manufactured in advance, and a joining steel plate attached to a joining portion of the precast reinforced concrete panel is joined on site, and the on-site joining portion is filled with mortar. In a joint structure of a wall-type precast concrete building that is to be buried in a field and assembled on site, the joining steel plate is fastened by high-strength bolt joining, and at least the high-strength bolt and the nut portion are made of synthetic resin. A joint structure for a wall-type precast concrete building, characterized in that the joint steel plate on which the covering layer is formed is covered by the mortar and is covered with the covering layer. 2. A through hole formed in the floor slab through which a bonded steel plate connecting the load bearing walls of the upper and lower floors with the floor slab interposed therebetween,
The joint structure of a wall-type precast concrete building according to claim 1, wherein the lower surface of the floor slab has a tapered shape formed wider than the upper surface of the floor slab. 3. The joint structure of a wall-type precast concrete building according to claim 1, wherein said synthetic resin coating layer comprises a coating film of a synthetic resin paint. 4. The joint structure of a wall-type precast concrete building according to claim 1, wherein said synthetic resin coating layer is made of a synthetic resin sticking sheet.