JP4182881B2 - Reinforcement structure of beams and slabs in existing buildings - Google Patents

Description

  The present invention relates to a beam / slab reinforcement structure in an existing building.

  When an applied load exceeding the allowable capacity of the original design is applied to some or all of the existing horizontal members such as beams and slabs by changing the use of existing buildings or installing large heavy objects on the floor of the building There is.

  Conventionally, various reinforcing structures shown in FIG. 10 have been adopted as a reinforcing structure for an existing building in such a case. 10 (a) to 10 (c) show examples of reinforcement in the RC column-beam structure, and FIGS. 10 (d) and 10 (e) show examples of reinforcement in the S-column / beam structure. . 10 (a), a steel bundle column 3 is installed between the center of the beam 1 and the floor 2. In FIGS. 10 (b) and 10 (d), a steel frame column is formed between the beam 1 and the columns 4 on both sides thereof. In FIG. 10 (c) and FIG. 10 (e), a steel frame reinforcing beam 6 having both ends supported by columns 4 is arranged in parallel in FIG. The non-shrink mortar 7 is filled between the reinforcing beams 6 and the beams 1 and the reinforcing beams 6 are connected by welding 8.

  However, in each of the cases shown in FIGS. 10 (a), 10 (b), and 10 (d), an obstacle occurs in the lower space, and there is a problem that the degree of freedom of the space is lowered.

  On the other hand, in the structures of FIG. 10C and FIG. 10E, the degree of freedom of the lower space is secured, but in FIG. 10C, the reliability is poor in terms of whether or not it closely contacts the beam. In 10 (e), the workability is poor because the welding operation is upward. Furthermore, in any structure, when the beam and slab are already subjected to stress and deformation, it is difficult to correct the structure.

  The present invention solves the above-mentioned problems, and while securing the degree of freedom of the lower space, it is possible to securely and easily reinforce the members and maintain beams and slabs in existing buildings that can be held below the allowable strength. A reinforcing structure is provided.

The beam / slab reinforcement structure in the existing building of the present invention that achieves the above object is provided with a reinforcement beam in parallel with the lower part of an existing horizontal member such as a beam or floor slab, and both ends of the existing vertical member. It is fixed between, by interposing a reaction member in the gap between the existing horizontal member and the reinforcing beams, by the action of upward force to the existing horizontal member by widening the gap at reaction force member It was a reinforcing structure of the beam slab in the existing building,
The reaction force member widens the gap between the reinforcing beam and the existing horizontal member, and the push-up force is managed by the deflection amount of the reinforcing beam generated by the widening (first invention) ).

The beam / slab reinforcement structure in the existing building of the second invention is such that a reinforcement beam is attached in parallel to the lower part of an existing horizontal member such as a beam or a floor slab, and both ends thereof are fixed between existing vertical members. In addition, a reaction force member is interposed in the gap between the reinforcing beam and the existing horizontal member, and the gap is widened by the reaction force member and the widening is maintained, thereby pushing up the existing horizontal member. a reinforcing structure of the beam slab in the existing building, which was allowed to act,
The reaction force member widens the gap between the reinforcing beam and the existing horizontal member, and the push-up force is managed by the deflection amount of the reinforcing beam generated by the widening.

The beam / slab reinforcement structure in the existing building of the third invention is such that a reinforcement beam is attached in parallel to the lower part of an existing horizontal member such as a beam or a floor slab, and both ends thereof are fixed between existing vertical members. In addition, a gap widening member is interposed in the gap between the reinforcing beam and the existing horizontal member, the gap is widened by the gap widening member, and the widening is held by the reaction force member, whereby the existing horizontal member is Reinforcement structure of beams and slabs in an existing building where push-up force is applied ,
The gap widening member widens the gap between the reinforcing beam and the existing horizontal member, and the push-up force is managed by the amount of deflection of the reinforcing beam generated by the widening.

  According to a fourth aspect of the present invention, there is provided the beam / slab reinforcement structure according to any one of the first to third aspects, wherein the existing vertical member is an existing column, a vertical surface of the existing beam orthogonal to the reinforcement beam, an existing earthquake resistance It is characterized by being selected from the walls or a combination thereof.

  The reinforcement structure of the beam and slab in the existing building of the fifth invention is that in any one of the first to fourth inventions, the existing vertical member and the reinforcement beam are joined via a reinforcing material such as a steel frame. Features.

  The beam / slab reinforcement structure in the existing building of the sixth invention is the gap between the reinforcement beam and the existing horizontal member in the reaction force member or the widening member in any one of the first to fifth inventions. And the gap is filled with a filler such as non-shrink mortar.

  With the above configuration, in the present invention, the stress applied to the existing horizontal member can be reduced by applying a pushing force to the existing horizontal member by the reaction force member. Further, even when the existing horizontal member is already subjected to stress and deformation, it can be easily corrected.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a stress (bending moment) diagram acting on an existing horizontal member showing the basic principle of the present invention, (a) a state diagram in which a pushing force is applied to one point of the existing horizontal member, and (b) an existing horizontal member FIG. 6 is a state diagram in which a pushing force is applied to a plurality of points of a member.

  As shown in Fig. 1 (a), when an excessive load is applied to an existing horizontal member such as a beam or floor slab, the existing horizontal member is based on both side support points (vertical members such as columns and walls). A stress is generated that greatly deflects the center downward. In contrast, a reinforcing beam is arranged at the lower part of the existing horizontal member, and as shown in FIGS. 1 (a) and 1 (b), an upward push-up force P is applied at one upper center and two upper parts of the reinforcing beam. By acting, the stress of the existing horizontal member is reduced and the proof stress is improved. Normally, as shown in FIG. 1 (a), the push-up force P is applied at one central position. However, when the span of the existing horizontal member and the reinforcing beam is large, the load position acting on the existing member is taken into consideration. For the reason, as shown in FIG. 1 (b), it is possible to apply the push-up force P at two or more locations.

  FIG. 2 is a front view showing a reinforcing structure of a large beam of an RC building in the first embodiment of the present invention.

As shown in FIG. 2, a large beam 14 is provided horizontally between a pair of columns 10, a floor slab 12 is integrated on the upper portion, and a large beam 16 is provided in a direction perpendicular to the paper surface of each column 10.
Further, a predetermined gap d is provided on the lower surface of the large beam 14, for example, steel reinforcing beams 18 made of H-shaped steel are arranged in parallel, and both ends thereof are connected between the columns 10 via the connecting portions 20. Yes.
As shown in an enlarged view in part of FIG. 2, the connecting portion 20 is inserted into an anchor hole 10a drilled in the side surface of the column 10 and fixed by a resin or the like, and the column 10 by the anchor bolt 20a. The base plate 20b is fixed to the side of the base plate 20b, and one end of the base plate 20b is connected to the base plate 20b and the other end is connected to the web of the reinforcing beam 18 by bolts.

3 shows a cross section of FIG. 2, (a) AA cross section, (b) BB cross section.
As shown in FIG. 3A, a push-up screw type reaction force member 22 is provided at the upper end of the reinforcing beam 18.
Further, as shown in FIG. 3B, buckling prevention members 24 made of, for example, an L-shaped angle member are provided at both corners of the lower end portion of the large beam 14, and further, a non-shrink mortar is provided in the gap d. 26 is filled, and the reinforcing beam 18 is integrally connected to the lower portion of the large beam 14. In this embodiment, an L-shaped angle member is used for the buckling prevention member, but any shape and material may be used as long as it has a buckling prevention function.

  FIG. 4 shows a state in which a pushing-up force is applied by the reaction force member in the first embodiment of the present invention, (a) a state diagram in which the reaction force member is installed at a predetermined position, and (b) a pushing force by the reaction force member It is the state figure made to act.

  As shown in FIG. 4A, the screw-type reaction force member 22 penetrates, for example, the upper flange surface of the reinforcing beam 18, the center sandwiches the web, and a total of four push-up bolts 22a and a bolt It consists of four welding nuts 22b fixed to the flange surface so as to face 22a, and a metal plate 22c for receiving bolts common to each bolt 22a fixed to the center position of the bottom of the large beam 14 by an adhesive. In this embodiment, four push-up bolts are used, but the number can be changed as necessary. Further, in this embodiment, the push-up bolt is used as the reaction force member. However, any shape and material may be used as long as it has a function of applying the reaction force.

  As shown in FIG. 4B, by screwing the bolts 22a from the state where the pushing force is not applied, the above-described pushing force P is generated by the reaction force, and the pushing force P can be held. Further, by filling the non-shrinkable mortar 26 in the gap d, it is possible to maintain the push-up force P and to perform more effective reinforcement for continuing the push-up force. In addition, filling with mortar or the like is not essential in the present invention but is performed in an auxiliary manner.

FIG. 5 is a schematic view showing the deflection amount of the reinforcing beam in the first embodiment of the present invention.
As shown in FIG. 5, the push-up force P is managed by screwing each bolt 22a so that the center position of the reinforcing beam 18 becomes a predetermined deflection amount λ by the push-up reaction force.

  FIG. 6 is a front view showing a beam reinforcing structure of an RC building in the second embodiment of the present invention. In addition, the same code | symbol is attached | subjected and demonstrated to the part same as the said 1st Embodiment, or an equivalent.

  As shown in FIG. 6, the large beam 14 is parallel to one side in the direction orthogonal to the paper surface, and the small beam 17 is parallel to the other side. Then, the floor slab 12 is pushed up by the screw type reaction force member 22, and the non-shrink mortar 26 is filled in the gap between the reinforcing beam 18 and the floor slab 12 while being held. The case where the reinforcement beam 18 is connected integrally is shown.

  In this embodiment, as shown in FIG. 6, when the leg part of the heavy equipment W is located on the floor slab 12, it is suitable as a structure for reinforcing the part directly below the leg part.

FIG. 7 is a front view showing a beam reinforcing structure of an RC building in the third embodiment of the present invention.
As shown in FIG. 7, the large beam 14 is arranged in one direction orthogonal to the paper surface, the wall 28 is parallel to the other, and the small beam 19 is arranged in the direction orthogonal to the large beam 14 and the wall 28. The case where the reinforcement beam 18 is arrange | positioned to the lower part is shown.

  In the present embodiment, the gap d ′ of the reinforcing beam 18 with respect to the small beam 19 is large. Therefore, a second reinforcing beam 18 ′ is provided in parallel with the lower part of the large beam 14, and one end of the reinforcing beam 18 is fixed to the side surface of the second reinforcing beam 18 ′ via a connecting plate 30 or the like. The other end is connected to the wall 28 through a through bolt 32.

  Further, a raised portion 34 made of a plate material is projected at the center of the reinforcing beam 18, and the small beam 19 is pushed up and supported by a screw type reaction force member 22 provided on the upper portion of the raised portion 34. The non-shrink mortar 26 is filled between the raised portion 34 and the small beam 19, and the reinforcing beam 18 is integrally connected to the lower surface of the small beam 19 via the raised portion 34.

  Further, the second reinforcing beam 18 ′ arranged in parallel below the large beam 14 can push up and support the large beam 14 by the same structure as in the first embodiment.

  In the present embodiment, since the gap d ′ between the small beam 19 and the reinforcing beam 18 disposed below it is large, for example, a pushing force is introduced using a gap widening member such as a hydraulic jack 36. Is also possible. In this case, the screw reaction force member 22 is adjusted while being pressurized by the hydraulic jack 36, and the hydraulic jack 36 is removed while the push-up force P is held by the screw reaction force member 22. In the present embodiment, the hydraulic jack is used as the gap widening member, but any shape and material may be used as long as it has a function of widening the gap.

FIG. 8 is a front view showing a beam reinforcing structure of an RC building in the fourth embodiment of the present invention.
In the present embodiment, when the support strength of the column 10 of the first embodiment is insufficient, the side surface of the column 10 at the end joint position of the reinforcing beam 18 has, for example, a concave cross section reaching the floor surface side, H A steel reinforcing member 38 having a shape or the like is fixed through a large number of anchor bolts 40 to reinforce the column 10, and one end of the connecting beam 18 is joined through the connecting plate 30. In this embodiment, the reinforcing member is a steel frame having a concave cross section, an H shape, or the like, but any shape and material may be used as long as it has a function of supplementing the support strength of the pillar.
Therefore, this embodiment can cope with a case where the support strength of the pillar 10 is insufficient.

FIG. 9 is a diagram showing a beam reinforcing structure for an RC building in the fifth embodiment of the present invention.
As shown in FIG. 9, the large beam 14 is parallel to one of the directions orthogonal to the paper surface, the small beam 17 is parallel to the other, and the floor slab 12 is pushed up and supported by the reinforcing beam 18 between the large beam 14 and the small beam 17. Although it is the same as that of 2nd Embodiment, the point which receives not the both ends of the reinforcement beam 18 by each beam 14 and 17 but the reinforcement member 38 via a pair of steel-made bundle members 42 differs.
Further, both ends of the reinforcing beam 18 are joined to the side surfaces of the beams 14 and 16 via angle members 44. The angle member 44 is joined to prevent buckling of the reinforcing beam 18.
The screw-type reaction force member 22 is arranged at the center of the reinforcing beam 18 to apply a pushing force to the floor slab 12 and to fill the non-shrinking mortar 26 so as to be integrally connected to the floor slab. This is the same as in the second embodiment.
Moreover, in each embodiment, although this invention was used for the push-up reinforcement of the existing building of RC structure, it is applicable similarly to the existing building of S structure.

It is the stress (bending moment) figure which acts on the existing horizontal member which shows the basic principle of this invention, (a) The state figure which made pushing-up force act on one point of the existing horizontal member, (b) The plurality of existing horizontal members It is the state figure which applied the pushing-up force to the point. It is a front view which shows the reinforcement structure of the big beam of RC structure building in 1st Embodiment of this invention. The cross section of FIG. 2 is shown, (a) AA sectional drawing, (b) BB sectional drawing. The state which makes push-up force act with the reaction force member in 1st Embodiment of this invention is shown, (a) The state figure which installed the reaction force member in the predetermined position, (b) The push-up force was made to act on the reaction force member It is a state diagram. It is the schematic which shows the deflection amount of the reinforcement beam in 1st Embodiment of this invention. It is a front view which shows the reinforcement structure of the beam of RC building in 2nd Embodiment of this invention. It is a front view which shows the reinforcement structure of the beam of RC building in 3rd Embodiment of this invention. It is a front view which shows the reinforcement structure of the beam of RC building in 4th Embodiment of this invention. It is a figure which shows the reinforcement structure of the beam of RC building in 5th Embodiment of this invention. (A)-(e) is explanatory drawing which shows each example of the conventional reinforcement structure.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Column 12 Floor slab 14, 16 Large beam 17 Small beam 18 Reinforcement beam 20 Connection part 22 Screw type reaction force member 26 Non-shrink mortar 28 Wall 30 Connection plate 38 Reinforcement member 40 Anchor bolt P Push-up force

Claims (6)

At the bottom of the existing horizontal member such as a beam or floor slab, a reinforcing beam is attached in parallel to this, and both ends thereof are fixed between the existing vertical members, and in the gap between the reinforcing beam and the existing horizontal member. A beam / slab reinforcement structure in an existing building in which a reaction force member is interposed, and the gap is widened by the reaction force member to exert a pushing force on the existing horizontal member,
The beam in the existing building is characterized by widening a gap between the reinforcing beam and the existing horizontal member by the reaction force member, and managing a push-up force by a deflection amount of the reinforcing beam generated by the widening. Slab reinforcement structure. At the bottom of the existing horizontal member such as a beam or floor slab, a reinforcing beam is attached in parallel to this, and both ends thereof are fixed between the existing vertical members, and in the gap between the reinforcing beam and the existing horizontal member. It is a reinforcing structure for beams and slabs in an existing building in which a reaction force member is interposed, the gap is widened by the reaction force member, and a push-up force is applied to the existing horizontal member by holding the widening ,
The beam in the existing building is characterized by widening a gap between the reinforcing beam and the existing horizontal member by the reaction force member, and managing a push-up force by a deflection amount of the reinforcing beam generated by the widening. Slab reinforcement structure. At the bottom of the existing horizontal member such as a beam or floor slab, a reinforcing beam is attached in parallel to this, and both ends thereof are fixed between the existing vertical members, and a gap is formed in the gap between the reinforcing beam and the existing horizontal member. A beam / slab reinforcement structure in an existing building in which a widening member is interposed, the gap is widened by the gap widening member, and the widening is held by a reaction force member, and a pushing force is applied to the existing horizontal member. There,
The gap in the existing building is characterized in that the gap between the reinforcing beam and the existing horizontal member is widened by the gap widening member, and the push-up force is managed by the deflection amount of the reinforcing beam generated by the widening. Slab reinforcement structure.   The existing vertical member according to any one of claims 1 to 3, wherein the existing vertical member is selected from an existing column, a vertical surface of an existing beam orthogonal to the reinforcing beam, an existing earthquake-resistant wall, or a combination thereof. Reinforcement structure for beams and slabs in existing buildings.   5. The beam / slab reinforcement structure in an existing building according to any one of claims 1 to 4, wherein the existing vertical member and the reinforcement beam are joined to each other via a reinforcing material such as a steel frame. In any one of Claims 1-5, the clearance gap between the said reinforcement beam and the said existing horizontal member is expanded by the said reaction force member or the said clearance gap widening member , and filling materials, such as a non-shrink mortar, are filled in this clearance gap. Reinforcement structure for beams and slabs in existing buildings.

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