JP2002213085A - Reinforcing structure for existing building - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reinforcing structure whose construction work is executable in a relatively short period, and which increases resistance to bending stresses working on beams, without deteriorating habitability of an existing building. SOLUTION: A plurality of beam reinforcing members 31 and 32 made of precast concrete are pressed against the outside of an existing beam 12 by a PC steel rod 23 via mortar 29. A PC strand 22 is passed through a predetermined number of adjacent beam reinforcing members and a tensile force is introduced therein to connect them integrally with one another. A column reinforcing member 41 made of precast concrete is disposed on the outside of an existing column 11 between a predetermined beam reinforcing member and a predetermined balcony slab 13. A PC strand 43 is passed through the beam reinforcing member, the balcony slab and the column reinforcing member via blocks of joint mortar 28a, 28b and 28c and a tensile force is introduced into the strand to connect them integrally with one another.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reinforcing structure for an existing concrete building using a reinforcing member made of PCa concrete.

[0002]

2. Description of the Related Art Conventionally, in order to reinforce an existing concrete building, a brace has been conventionally attached to the outside of an existing column or an existing beam, an existing column or an existing beam has been reinforced with reinforced concrete, and an existing column or beam has been conventionally used. Walls are being built with cast-in-place concrete within the frame. However, when a brace is attached to the outside of an existing building, the view from the window is obstructed, and when the brace is used as a veranda, it becomes difficult to enter and exit, and the veranda becomes narrower, which deteriorates habitability. In addition, the brace only restricts the existing column-beam frame so as to suppress the relative horizontal displacement, and has a drawback that the strength against bending stress acting on the beam cannot be reinforced. Also, when adding existing pillars or adding walls with cast-in-place concrete, building users must temporarily leave the building,
The disadvantage is that it takes a lot of time and money.

[0003]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a construction which can be carried out in a relatively short period of time without deteriorating the livability in an existing building, and furthermore, a bending acting on a beam. An object of the present invention is to provide a reinforcing structure capable of reinforcing the strength against stress.

[0004]

According to the present invention, there is provided a reinforcing structure for an existing concrete building, in which a plurality of beam reinforcing members made of precast concrete are crimped to the outside of the existing beam with a tension member via a pressure receiving member. A reinforcement structure for an existing building is provided, wherein a tension member is inserted into a predetermined number of matching beam reinforcing members, and a tension is introduced into the tension members to be integrally connected.

Here, the precast concrete beam reinforcing member is preferably provided with through-holes in advance in the axial direction and a direction substantially perpendicular thereto, and these through-holes are used as insertion holes for the tendon. . The through-hole in the axial direction of the material is used to insert the tendon into it and connect the adjacent beam reinforcing members, and the through-hole in the direction substantially perpendicular to the material axis is inserted through the tendon. It can be used for crimping a beam reinforcing member to an existing beam.

Further, in the present invention, a column reinforcement member made of precast concrete is disposed outside the existing column between the predetermined beam reinforcement member and the predetermined existing slab material, and the beam reinforcement member and the existing slab material are connected to each other. It is preferable that a tension member is inserted into the column reinforcing member via a pressure receiving member, and a tension is introduced into the tension member to integrally connect the tension members. In this case, the precast concrete column reinforcing member is provided with a through hole in the axial direction of the material, and the column reinforcing member and the existing slab material are also provided with through holes so as to communicate with the through hole. It is preferably used as a material insertion hole.

[0007] The pressure-receiving member may be any member that can provide frictional resistance that makes it difficult to cause slippage at the crimped portion between the beam reinforcing member and the outside of the existing beam. Can be formed. The tension member may be a PC steel wire, a PC steel strand, or a PC steel wire.
It is preferable to use a PC tendon such as a steel bar. As the beam reinforcing member and the column reinforcing member made of precast concrete, a member in which prestress is introduced may be used.

[0008]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a front view of a reinforcing structure according to the present invention, partially illustrating first and second floors of an existing building. The reinforcing structure shown in FIG. 1 uses a plurality of precast concrete beam reinforcing members 31 and 32 via a mortar 29 (see FIG. 4) as a pressure receiving member.
2 is press-fitted with a PC steel rod 23, and a joint mortar 26 as a pressure receiving member is filled between the beam reinforcing members 31 and 32, and the PC strand 22 is inserted into the adjacent beam reinforcing members 31 and 32 to introduce tension into the beam. And connected together.

The beam reinforcing members 31 and 32 have a plurality of through holes (not shown) in the direction of the material axis and in a direction substantially perpendicular to the material axis. The PC strand 22 is inserted through the through-hole in the axial direction of the material, and a fixing tool 25 such as a support plate or a grip is attached to the end of the PC strand 22, and the tensioned PC strand 22 is fixed to the beam reinforcing members 31 and 32. I do. Existing beam 12
A through hole (not shown) is formed at a position corresponding to the through hole in the direction perpendicular to the material axis, and PC holes are formed in both of the corresponding through holes.
A steel rod 23 is inserted, and a fixing member 24 such as a support plate or a grip is attached to the end of the steel rod 23, and the PC steel rod 2 to which tension is introduced.
3 is fixed to the beam reinforcing members 31 and 32 and the existing beam 12.
The PC strand 22 has 300 to 70 pieces per piece.
Approximately 0 kilonewton, 3 per PC steel bar 23
A tension of about 00 to 900 kilonewtons is introduced. Further, it is preferable that the through-holes in the direction perpendicular to the material axis be provided at least near the ends of the beam reinforcing members 31 and 32 as shown in the figure.

In FIG. 1, a beam reinforcing member 31 disposed at an end of an existing building is formed to be slightly shorter than the length of one span. It is fixed in such a way that it stops. On the other hand, the beam reinforcing member 32 is formed to have a length of approximately one span.
It is fixed in such an arrangement as to reach the pillars 11 on both sides. The lengths of these beam reinforcing members and the locations of the existing beams 12 are not limited to the embodiment shown in FIG. 1, but are appropriately determined according to the strength of the existing beams of the existing building.

As described above, in the reinforcing structure of the present invention,
Each of the beam reinforcing members 31, 32 is press-bonded to the existing beam 12 with the PC steel bar 23, and the adjacent beam reinforcing members 31, 32 are integrally connected by the PC strand 22, so that the resistance of each of the existing beams 12 to bending stress is increased. In addition to the above, even when a large bending stress is applied to one existing beam 12 in a biased manner, the bending stress is transmitted to the other beams via the plurality of beam reinforcing members 31 and 32 integrally pressed by the PC strand 22. Since it is distributed to the existing beams 12 and the existing columns 11, the concentration of bending stress can be prevented, and the seismic performance of the entire building can be improved.

FIG. 2 is a front view showing a reinforcing structure in a mode different from that of FIG. 1. However, since the length of the beam reinforcing member and the location of the beam reinforcing member in the existing beam 12 are different from those of FIG. The same reference numerals are given to the same components as those in FIG. In FIG. 2, the existing beam 12 on the second floor is shown.
The beam reinforcing member 33 attached to the column is formed to have a length spanning a plurality of spans, and both ends thereof are fixed so as to reach the column 11. The beam reinforcing member 34 attached to the existing beam 12 on the first floor is formed to have a length corresponding to approximately one span, and is fixed such that both ends are located substantially in the center of the existing beam 12. In the reinforcing structure of FIG. 2, similarly to the reinforcing structure of FIG. 1, when the bending stress acts in a biased manner, the bending stress is reduced by the plurality of beam reinforcing members 31, 33, and 34 integrally pressed by the PC strand 22. The existing building 12 is distributed to the existing beams 12 and the existing columns 11 via, so that the earthquake resistance of the entire building is improved.

Another embodiment will be described with reference to FIGS. FIG. 3 is a front view showing a reinforcing structure in a mode different from FIGS. 1 and 2, and FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. 3 and 4, a plurality of precast concrete beam reinforcing members 32 are press-bonded to the existing beams 12 with PC steel rods 23 via mortars 29, respectively, and are used as pressure-receiving members between adjacent beam reinforcing members 32. Is filled with the joint mortar 26, the PC strand 22 is inserted into a plurality of adjacent beam reinforcing members 32, and a tension is introduced thereto to integrally connect the plurality of beam reinforcing members 32. Existing pillar 1 between balcony slab 13
A column reinforcing member 41 is provided on the outside, and joint mortars 28a, 28b, and 28c as pressure-receiving members are filled between the members, and PC strands 43 are mounted on the beam reinforcing member 32, the balcony slab 13, and the column reinforcing member 41. It is inserted and connected integrally by applying tension to it.

The column reinforcing member 41 has a plurality of through holes (not shown) in the axial direction of the material, and through holes (not shown) at the locations of the balcony slab 13 and the beam reinforcing member 32 corresponding to the through holes. Are drilled, and PCs are inserted into these corresponding through holes.
The strand 43 is inserted. In order to fix the lower end of the PC strand 43, the underground beam 15 is provided with a fixing concrete member 27 fixed by an anchor 27a. A tension of about 300 to 700 kilonewtons is introduced into each PC strand 43, and the lower end of the PC strand 43 is fixed using a fixing device 45 such as a support plate or a grip.
7 and the upper end of the PC strand 43 is fixed on the balcony slab 13 by a fixing tool 25 such as a support plate or a grip. In FIG. 3, all existing pillars 1 on the first floor
1 shows an example in which the column reinforcing members 41 are disposed outside the first floor and the column reinforcing members 41 are disposed every two spans on the second floor. It is not limited, and is appropriately determined according to the strength of the existing building including the existing pillars. The beam reinforcing member 32
Are the same as the members denoted by the same reference numerals in FIG. 1 except for the through holes provided for inserting the PC strands 43, and further description is omitted below.

As described above, in the reinforcing structure shown in FIGS. 3 and 4, each beam reinforcing member 32 is press-bonded to the existing beam 12 with the PC steel bar 23, and the adjacent beam reinforcing member 32 is connected to the PC strand 22.
And the column reinforcing member 41 is connected to the beam reinforcing member 32 and the balcony slab 13 by the PC strand 43.
The bending stress acting on each of the existing beams 12 is distributed to the plurality of beam reinforcing members 32 integrally pressed by the PC strands 22 and the column reinforcing members 41 are interposed via the beam reinforcing members 32. Is also dispersed, so that the concentration of bending stress can be prevented, and the seismic performance of the entire building can be improved. In the reinforcing structure of FIGS. 3 and 4, if the column reinforcing member 41 is rigidly connected to the beam reinforcing member 32 at the upper end and to the balcony slab 13 by the PC strand 43 at the lower end, there is no need to crimp the existing column 11. And therefore the existing pillar 11
The construction can be simplified without damaging the construction.

[0016]

According to the reinforcing structure of the present invention, since the beam reinforcing member is crimped to the existing beam with the tendon, and the adjacent beam reinforcing members are integrally connected with the tendon, the bending stress applied to the existing beam is reduced by the tension. It is dispersed to other existing beams and columns through a plurality of beam reinforcing members integrally pressed with a material, thereby preventing concentration of bending stress and improving the seismic performance of the entire building. Further, when a column reinforcing member is provided in addition to the beam reinforcing member, the bending stress applied to the existing beam is further dispersed from the beam reinforcing member to the column reinforcing member, and the seismic performance of the building is further enhanced.

In the reinforcing structure of the present invention, the reinforcing structure is constituted by attaching the beam reinforcing member and the column reinforcing member made of precast concrete to the column and beam frame of the existing building. Therefore, the field of view and the lighting area can be maintained almost the same as before the reinforcement without opening the windows and the like by the reinforcing material.

In the reinforcing structure of the present invention, the work on the existing building is performed by providing a through hole in the existing beam or the existing slab material.
Since only the work of installing the beam reinforcing members and column reinforcing members by introducing tension into the tendon members, the construction period and on-site work are reduced compared to the conventional method of adding columns and increasing the number of walls. This makes it possible to form a reinforcing structure without deteriorating livability in an existing building in use.

[Brief description of the drawings]

FIG. 1 is a front view of a reinforcing structure for an existing building according to the present invention.

FIG. 2 is a front view showing a reinforcing structure in a mode different from that of FIG.

FIG. 3 is a front view showing a reinforcing structure in a mode different from FIGS. 1 and 2;

FIG. 4 is a sectional view taken along the line IV-IV in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Existing pillar 12 Existing beam 13 Balcony slab (existing slab material) 22 PC strand (tensile material) 23 PC steel rod (tensile material) 26 Joint mortar (pressure-receiving member) 28a, 28b, 28c Joint mortar (pressure-receiving member) 29 mortar ( Pressure receiving members) 31, 32, 33, 34 Beam reinforcing members 41 Column reinforcing members 43 PC strands (tensile members)

Claims (2)

[Claims] 1. A reinforcing structure for an existing concrete building, wherein a plurality of beam reinforcing members made of precast concrete are crimped to the outside of an existing beam with a tension member via a pressure receiving member, and a predetermined number of adjacent beam reinforcing members are used. A reinforcement structure for existing buildings, characterized in that a tension material is inserted into the material and tension is introduced into the material to connect them together. 2. A column reinforcement member made of precast concrete is provided outside an existing column between a predetermined beam reinforcement member and a predetermined existing slab material, and the beam reinforcement member, the existing slab material, and the column reinforcement are provided. The reinforcing structure according to claim 1, wherein a tension member is inserted into the member via a pressure receiving member, and tension is introduced into the tension member to be integrally connected.