JP2015218561A - Seismic strengthening structure and seismic strengthening method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve aseismic capacity of existing peripheral columns without significantly reducing an effectively usable interior space in a building.SOLUTION: A seismic strengthening structure 10 comprises: existing peripheral columns 16 arranged on a periphery of a building 12; and extension sections 24 which are positioned next to the respective existing peripheral columns 16 in a peripheral direction of the building 12 and integrated therewith. The extension sections 24 are constructed by reinforced concrete with a plurality of main reinforcing bars and a plurality of hoops surrounding the same, and integrated with the peripheral columns 16 by being connected thereto through anchor members which are post-construction anchors.

Description

  The present invention relates to a seismic reinforcement structure and a seismic reinforcement method for improving the seismic resistance of existing columns.

  As a seismic reinforcement structure that enhances the earthquake resistance of the existing pillar, there is a structure in which concrete is added to surround the entire circumference of the existing pillar or a reinforcing member is provided.

  For example, Patent Literature 1 discloses a seismic reinforcement structure in which a reinforcing steel plate is installed on an existing column and a grout is filled between the existing column and the reinforcing steel plate.

  However, when such an earthquake-proof reinforcement structure is applied to an existing outer peripheral column arranged on the outer peripheral part of a building, an indoor space that can be effectively used by the building becomes an additional cast concrete part provided on the inner side of the existing outer peripheral column or It will be significantly narrowed by the reinforcing member.

JP-A-9-273318

  This invention considers the fact which concerns, and makes it a subject to improve the earthquake resistance of the existing outer periphery pillar, without significantly narrowing the indoor space which can be utilized effectively of a building.

  The invention of the first aspect includes an existing outer peripheral column disposed in an outer peripheral portion of a building, and an extension portion adjacent to the existing outer peripheral column and the outer peripheral direction of the building and provided integrally with the existing outer peripheral column. Seismic reinforcement structure.

  In the first aspect of the invention, the existing outer peripheral column can be reinforced with the extension portion, thereby improving the earthquake resistance of the existing outer peripheral column.

  Moreover, since the extension part is provided so that the existing outer periphery pillar and the outer peripheral direction of a building may be adjacent, it can suppress that the indoor space which can be used effectively of a building becomes significantly narrow by providing an extension part. .

  Furthermore, by providing the additional portion so as to be adjacent to the existing outer peripheral column and the outer peripheral direction of the building, the shear strength of the existing outer peripheral column can be increased without increasing the bending strength of the existing outer peripheral column. Thereby, the toughness of an existing outer periphery column can be improved and the earthquake resistance of an existing outer periphery column can be improved.

  According to a second aspect of the present invention, in the seismic reinforcement structure according to the first aspect, the additional portion is formed of concrete and has a strip that surrounds a main reinforcing bar provided inside the additional portion, and the existing member is provided by an anchor member. It is joined to the outer peripheral column.

  In the invention of the second aspect, the shear strength of the existing outer peripheral column can be reliably increased by joining the additional portion formed of concrete to the existing outer peripheral column by the anchor member.

  The invention of the third aspect is a seismic reinforcement method in which an extension portion is provided integrally with the existing outer peripheral column so as to be adjacent to the existing outer peripheral column arranged on the outer peripheral portion of the building in the outer peripheral direction of the building.

  In the invention of the third aspect, the same effect as in the first aspect can be obtained.

  Since this invention set it as the said structure, the earthquake resistance of the existing outer periphery pillar can be improved, without reducing indoor space which can be utilized effectively of a building significantly.

It is a top view which shows the standard floor of the existing building reinforced earthquake-proof with the earthquake-proof reinforcement structure which concerns on embodiment of this invention. It is a plane sectional view showing the earthquake-proof reinforcement structure concerning the embodiment of the present invention. It is a plane sectional view showing the earthquake-proof reinforcement structure concerning the embodiment of the present invention. It is a graph which shows the effect of the earthquake-proof reinforcement structure concerning the embodiment of the present invention. It is a plane sectional view showing the conventional earthquake-proof reinforcement structure. It is a plane sectional view showing the variation of the earthquake-proof reinforcement structure concerning the embodiment of the present invention. It is a plane sectional view showing the variation of the earthquake-proof reinforcement structure concerning the embodiment of the present invention.

  Embodiments of the present invention will be described with reference to the drawings. First, the seismic reinforcement structure according to the embodiment of the present invention will be described.

  In the plan view of FIG. 1, a reference floor 14 of an existing building 12 as a building is shown as an example in which earthquake-proof reinforcement is performed by the earthquake-proof reinforcement structure 10 of the present embodiment. Here, the seismic reinforcement structure 10 improves the seismic resistance of the existing building 12 with respect to the direction Y between the beams of the existing building 12. That is, the inter-beam direction Y is the seismic reinforcement direction.

  The existing building 12 is a reinforced concrete structure, and has an existing column 16, a frame beam 18, a floor slab 20, and an existing outer wall 22 formed of reinforced concrete.

  The seismic strengthening structure 10 is configured to include a frame column 16 as an existing outer peripheral column disposed on the outer peripheral portion of an existing building 12 and an extension portion 24 formed of reinforced concrete. The extension part 24 is disposed only at a position adjacent to the outer periphery direction S of the pillar 16 and the existing building 12 (in this embodiment, the outer periphery direction S is the same as the carry direction X of the existing building 12). It is not provided inside the existing building 12 with respect to the inter-beam direction Y.

  That is, the extension part 24 is provided only on one of the left and right side surfaces of the frame column 16 that is parallel to the inter-beam direction Y, which is the seismic reinforcement direction of the existing building 12. In other words, the extension part 24 is provided only on one of the left and right side surfaces of the frame column 16 when the frame column 16 is viewed from the outside of the existing building 12.

  For convenience of explanation, the plurality of seismic reinforcement structures 10 shown in FIG. 1 are assumed to be seismic reinforcement structures 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H, 10I, and 10J clockwise from the upper left.

  As shown in the cross-sectional plan view of FIG. 2, the extension portion 24 in the earthquake-proof reinforcement structure 10J is formed of concrete U, and includes a plurality of main bars 28 provided substantially vertically inside the extension portion 24 (concrete U), The main bar 28 has a girdle 30 surrounding it. The extension portion 24 is joined to the frame column 16 by an anchor member 26 that is a post-construction anchor, and is provided integrally with the frame column 16.

  As shown in the cross-sectional plan view of FIG. 3, the extension portion 24 in the earthquake-proof reinforcement structure 10 </ b> H is formed of concrete U and includes a plurality of main bars 28 provided substantially vertically inside the extension portion 24 (concrete U), The main bar 28 has a girdle 30 surrounding it. The extension portion 24 is joined to the frame column 16 by an anchor member 26 that is a post-construction anchor, and is provided integrally with the frame column 16.

  In this way, in the earthquake-proof reinforcement structures 10J and 10H, the extension portion 24 is formed so as to be a lump independent of the frame column 16 by providing the band 30 inside the extension portion 24 so as to surround the plurality of main bars 28. In this way, this lump (additional portion 24) is integrated with the frame column 16 by the anchor member 26.

  The seismic reinforcement structures 10A, 10E, and 10F shown in FIG. 1 have the same configuration as the earthquake resistant reinforcement structure 10J described in FIG. 2, and the seismic reinforcement structures 10B, 10C, and 10D shown in FIG. Since 10G, 10H, and 10I have the same configuration as the earthquake-proof reinforcement structure 10H described with reference to FIG.

  In the seismic strengthening method for constructing the seismic strengthening structure 10, the column 16 as an existing outer peripheral column arranged on the outer peripheral part of the existing building 12 and the main column 16 are integrated so as to be adjacent to the outer peripheral direction S of the existing building 12. An extension unit 24 is provided.

  Next, the operation and effect of the earthquake-proof reinforcement structure and the earthquake-proof reinforcement method according to the embodiment of the present invention will be described.

  In the seismic reinforcement structure 10 and the seismic reinforcement method of the present embodiment, as shown in FIGS. 1 to 3, the pillars 16 are reinforced with respect to the seismic reinforcement direction (inter-beam direction Y) by reinforcing the pillars 16 with the extension portions 24. Can improve the earthquake resistance.

  Moreover, since the extension part 24 is provided only in the position adjacent to the outer periphery direction S (in the example of FIG. 1, the direction X of the existing building 12) of the frame pillar 16 and the existing building 12, It is possible to prevent the indoor space that can be used for the vehicle from being significantly narrowed by providing the additional portion 24. That is, it is possible to suppress a decrease in the indoor space inside the existing building 12 from the frame column 16 with respect to the beam-interval direction Y.

  Furthermore, as shown in FIG. 1, by providing the extension part 24 only at the position adjacent to the outer circumferential direction S of the building column 16 and the existing building 12, the building column 16 can be moved in the direction of earthquake resistance (direction Y between beams). The shear strength of the frame column 16 can be increased without increasing the bending strength. Thereby, the toughness of the column 16 can be improved with respect to the earthquake-proof reinforcement direction (direction Y between beams), and the earthquake resistance of the column 16 can be improved. Further, by increasing the shear strength of the frame column 16 without increasing the bending strength of the frame column 16 with respect to the seismic reinforcement direction (inter-beam direction Y), the frame column can be efficiently added to the plane cross-sectional area of the extension portion 24. 16 earthquake resistance can be improved.

This will be described in more detail. As shown in the graph of FIG. 4A, it has a shear strength Q _S1 and a bending strength Q _m1 with respect to the seismic reinforcement direction (inter-beam direction Y) (the shear strength Q _S1 is smaller than the bending strength Q _m1 ). As shown in the plan cross-sectional view of FIG. 5A, the reinforced concrete column 16 is reinforced with reinforced concrete so as to surround the reinforced concrete column 16 and reinforced with a conventional aseismic reinforcing structure 34 that forms a reinforced portion 32. Since both the shear strength ΔQ _S and the bending strength ΔQ _m are given to the frame column 16 with respect to the seismic reinforcement direction (direction Y between beams), as shown in the graph of FIG. With respect to the seismic reinforcement direction (direction Y between beams), the shear strength Q _S2 is smaller than the bending strength Q _m2 (the column column 16 has a strength determined by the shear strength).

In contrast, in the seismic reinforcement structure 10, as shown in FIGS. 1 to 3, the extension part 24 is provided only at the position adjacent to the outer peripheral direction S of the building column 16 and the existing building 12, thereby providing the seismic reinforcement direction (between beams). to the direction Y), only the shear strength Delta] Q _S is applied to the precursor pillars 16, as shown in the graph of FIG. 4 (c), the Mukurotaihashira 16, to the earthquake-proof reinforcement direction (Harima direction Y) The bending strength Q _m3 is smaller than the shear strength Q _S3 (the column column 16 has a characteristic that the strength of the column 16 is determined by the bending strength). Strictly speaking, in the seismic reinforcement structure 10 as well, a slight bending strength is imparted to the frame column 16 with respect to the seismic reinforcement direction (inter-beam direction Y), but since the value is small, the bending strength Q is greater than the shear strength Q _{S3. m3} is a column having smaller characteristics. That is, the toughness of the column 16 can be improved.

  Therefore, by improving the toughness of the frame column 16 and increasing the earthquake resistance of the frame column 16 in the direction of seismic strengthening (direction Y between beams), the earthquake resistance of the column column 16 can be efficiently increased with respect to the plane cross-sectional area of the extension part 24. Can be increased.

  For example, as shown in the plan cross-sectional views of FIGS. 5A and 5B, the seismic reinforcement structure in which the reinforcing portion 32 is formed by adding reinforced concrete to the inside of the existing building 12 rather than the frame column 16 with respect to the inter-beam direction Y. In the case of 34 and 36, in order to greatly improve the proof strength of the frame column 16 with respect to the seismic reinforcement direction (direction Y between beams), it is necessary to increase the additional striking thickness (reinforcement portion 32). The indoor space that can be used effectively becomes narrower.

  Further, for example, as shown in the plan cross-sectional view of FIG. 5C, the seismic reinforcing structure 38 in which the reinforcing portion 32 is formed by adding reinforced concrete to the outside of the existing building 12 rather than the frame column 16 with respect to the inter-beam direction Y. In such a case, repair work for seismic reinforcement must be performed outside the existing building 12.

  Further, in FIGS. 5A to 5C, the column 16 has the characteristics shown in FIG. 4B, so that the column 16 can be efficiently combined with the plane cross-sectional area of the reinforcing portion 32. It is difficult to improve earthquake resistance.

  On the other hand, in the seismic reinforcement structure 10 of this embodiment, as shown in FIGS. 1-3, by providing the extension part 24 only in the position adjacent to the outer periphery direction S of the pillar 16 and the existing building 12, It is possible to prevent the indoor space that can be effectively used in the building 12 from being significantly narrowed by providing the extension portion 24, and to efficiently reduce the seismic reinforcement direction (interbeam direction Y) with respect to the plane cross-sectional area of the extension portion 24. ) Can improve the earthquake resistance of the column 16. Furthermore, since the extension part 24 is arranged inside the outer wall 22, it is possible to perform seismic reinforcement without renovating the outer wall 22, and the renovation work for seismic reinforcement need not be performed outside the existing building 12. Good.

  In addition, in the seismic reinforcement structure 10 and the seismic reinforcement method of the present embodiment, the extension column 24 formed of concrete is joined to the chassis column 16 by the anchor member 26, whereby the chassis column 16 with respect to the earthquake resistance reinforcement direction (direction Y between beams). The shear strength of can be reliably increased.

  The embodiment of the present invention has been described above.

  In addition, in this embodiment, although the example which has arrange | positioned the extension part 24 only to the position adjacent to the outer periphery direction S of the frame pillar 16 and the existing building 12 was shown, the extension part 24 is shown to Fig.6 (a)-(c). And as shown to Fig.7 (a)-(c), it should just be arrange | positioned only at at least one of the positions adjacent to the outer periphery direction S of the pillar 16 and the existing building 12. FIG.

  Moreover, the extension part 24 of the earthquake-proof reinforcement structure 10 shown by this embodiment may be formed with a cast-in-place concrete, and may be joined to the frame pillar 16 on the spot as a precast member.

  Furthermore, in this embodiment, although the example in which the frame column 16 to be subjected to seismic reinforcement is formed of reinforced concrete, various structures (reinforced concrete structure, steel structure, steel reinforced concrete structure, It can be applied to the outer peripheral column of CFT structure (Concrete-Filled Steel Tube).

  As mentioned above, although embodiment of this invention was described, this invention is not limited to such embodiment at all, Of course, in the range which does not deviate from the summary of this invention, it can implement in a various aspect.

10, 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H, 10I, 10J Seismic reinforcement structure 12 Existing building (building)
16 Frame pillar (existing outer peripheral pillar)
24 Extension part 26 Anchor member 28 Main reinforcement 30 Stirrup S Outer circumferential direction U Concrete

Claims (3)

An existing outer peripheral column arranged on the outer periphery of the building;
An extension part adjacent to the existing outer peripheral column and the outer peripheral direction of the building and provided integrally with the existing outer peripheral column;
Seismic reinforcement structure with   The seismic reinforcement structure according to claim 1, wherein the extension portion is formed of concrete and has a band reinforcing the main reinforcement provided inside the extension portion, and is joined to the existing outer peripheral column by an anchor member. .   A seismic reinforcement method for providing an additional portion integrally with the existing outer peripheral column so as to be adjacent to the existing outer peripheral column arranged on the outer peripheral portion of the building in the outer peripheral direction of the building.

Images