JP2016160637A - Method for restricting horizontal displacement - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for restricting horizontal displacement that follows a relative displacement of a part above a seismic isolator, and enables a horizontal restricting material to be fitted and removed readily.SOLUTION: A method for restricting horizontal displacement restricts horizontal displacement of an existing building 1 when base-isolating the existing building 1. The method for restricting horizontal displacement includes the following steps for: constructing a retaining wall 30 outside of the existing building 1 and forming a clearance space 7 between the retaining wall 30 and the existing building 1; and installing a plurality of steel floor units 40 between the retaining wall 30 and the existing building 1 as a horizontal restricting material capable of following displacement in a vertical direction, the steel floor unit including a steel beam member and a steel floor member.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a horizontal movement restraining method for securing horizontal holding strength by restraining horizontal movement of an existing building during construction, for example, when making an existing building seismic isolation.

Conventionally, seismic isolation retrofit construction is known in which an existing building having an underground floor is isolated at the capital level of the first floor underground.
In this seismic isolation retrofit work, a supporting work is installed on the first basement floor of an existing building, and the upper part from the first floor (hereinafter referred to as the building body) is temporarily supported by this supporting work. Then, seismic isolation devices such as laminated rubber are attached to the head of the basement on the first basement floor, and then the support is removed. As a result, the building body is supported by the seismic isolation device and the existing building is seismically isolated.

  Here, it is necessary to restrain the horizontal movement of the ground portion at the first floor level. For example, as shown in Patent Document 1, a mountain retaining wall is constructed on the outside of an existing building, and the ground between the mountain retaining wall and the outer wall surface of the existing building is excavated to create a space on the side of the existing building. Form a seismic isolation pit. And in this seismic isolation pit, horizontal movement restraint materials, such as a beam and a slab, are constructed between the building main body and the mountain wall of an existing building, and horizontal movement of a building main body is restrained (refer patent document 1). ). This horizontal movement restraint material is fixed to the mountain retaining wall and the existing building at both ends.

JP 2001-349065 A

  By the way, when installing the seismic isolation device, the building body is moved up and down with a jack. For this reason, the building body moves up and down relative to the mountain retaining wall. However, in Patent Document 1, both ends of the horizontal movement restraining material are fixed to the mountain retaining wall and the existing building. There was a risk of damaging the retaining wall and the structure of the building body.

  In addition, when the horizontal restraint material is a reinforced concrete slab or beam, it takes time to construct and remove, and noise is generated when the horizontal restraint material is removed, and it takes time to dispose of the generated demolition waste. There was a problem.

  It is an object of the present invention to provide a horizontal restraint method that can follow the relative movement in the vertical direction of the portion above the seismic isolation device and that is easy to attach and remove the horizontal restraint material.

  The horizontal movement restraining method according to claim 1 is a horizontal movement restraining method for restraining the horizontal movement of an existing building when the existing building (for example, an existing building 1 described later) is subjected to seismic isolation. A step of constructing a retaining wall (for example, a retaining wall 30 to be described later) outside the building and forming a space (for example, a later-described gap space 7) between the retaining wall and the existing building (for example, to be described later) Steel comprising a steel beam member (for example, a later-described beam member 41) and a steel floor member (for example, a later-described floor member 42) between step S1) and the retaining wall and the existing building. And a step of laying a floor unit (for example, a steel floor unit 40 described later) as a horizontal constraining material capable of following the movement in the vertical direction (for example, step S2 described later).

According to the present invention, a steel floor unit is used as the horizontal restraint material, instead of a conventional reinforced concrete slab or beam. Therefore, since no concrete is used for the horizontal constraining material as in the prior art, the generation of noise during removal can be suppressed, and no dismantling is generated. Accordingly, it becomes easy to attach and remove the horizontal restraint material.
In addition, since the beam member and the floor member are integrated into a steel floor unit, movement and transportation are facilitated and can be repeatedly used.

  In the horizontal movement restraining method according to claim 2, an anchor bolt (for example, anchor bolt 14 described later) is provided on an upper surface of the retaining wall or a horizontal surface at an intermediate height, and one end side of the steel floor unit is connected to the one end side. A loose hole (for example, a loose hole 46 to be described later) that is fixed to an outer wall surface of an existing building (for example, an outer wall surface 3 to be described later) and extends in the horizontal direction on the other end side of the steel floor unit is provided. The anchor bolt is inserted into the hole.

According to this invention, the anchor bolt is provided on the upper surface of the retaining wall or the horizontal surface of the intermediate height, and the anchor bolt is inserted into the loose hole of the steel floor unit. Therefore, when installing the seismic isolation device, even if the building main body is moved up and down with a jack, the anchor bolt can move inside the loose hole, and the steel floor unit can follow the vertical movement of the building main body.
Moreover, since the steel floor unit and the anchor bolt are joined by the loose hole, the construction clearance can be secured and the construction error of the anchor bolt can be absorbed.

  According to the present invention, it is possible to follow the relative movement of the upper part of the seismic isolation device, and it is easy to attach and remove the horizontal restraint material.

It is sectional drawing of the outer peripheral part of the existing building used as the application object of the horizontal movement restraint method which concerns on 1st Embodiment of this invention. It is sectional drawing of the outer peripheral part of the existing building in which seismic isolation was completed in the said embodiment. It is a flowchart of the procedure which makes an existing building seismic isolation in the said embodiment. It is explanatory drawing (the 1) of the horizontal movement restraint method which concerns on the said embodiment. It is explanatory drawing (the 2) of the horizontal movement restraint method which concerns on the said embodiment. It is a side view of the steel floor unit used for the horizontal movement restraint method concerning the embodiment. It is a top view of the steel floor unit which concerns on the said embodiment. It is AA sectional drawing of FIG. It is explanatory drawing (the 3) of the horizontal movement restraint method which concerns on the said embodiment. It is explanatory drawing (the 4) of the horizontal movement restraint method which concerns on the said embodiment. It is explanatory drawing of the horizontal movement restraint method which concerns on the modification of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description of the embodiments, the same constituent elements are denoted by the same reference numerals, and the description thereof is omitted or simplified.
[First Embodiment]
The existing building 1 shown in FIG. 1 has a reinforced concrete ramen structure and has an underground floor. Specifically, the existing building 1 includes a first-floor floor 10, a first-floor pillar 11, a first-floor beam 12, a first-floor floor 13, and the like. The side surface of the existing building 1 is referred to as an outer wall surface 3.

In the present embodiment, as shown in FIG. 2, the building main body is a part above the first floor level including the first floor beam 12 and the first floor 13 after being seismically isolated at the column head of the first floor pillar 11. 4 is supported by the seismic isolation device 20.
Further, the retaining wall 30 is constructed by excavating the ground 5 outside the existing building 1, and the space between the retaining wall 30 and the building body 4 is defined as a seismic isolation pit 6.

  The retaining wall 30 includes a bottom plate 31, a vertical wall 32 erected on the outer end portion of the bottom plate 31, a floor slab 33 extending inward from the upper end of the vertical wall 32, and an inner end portion of the floor slab 33. And a rising portion 34 that is erected.

Hereinafter, the procedure for seismic isolation of the existing building 1 will be described with reference to the flowchart of FIG.
In step S <b> 1, as shown in FIG. 4, a retaining wall 30 is constructed outside the existing building 1, and a gap space 7 is formed between the retaining wall 30 and the outer wall surface 3 of the existing building 1.
At this time, the upper surface of the floor slab 33 of the retaining wall 30 is made substantially horizontal.

  In this step S1, anchor bolts 14 and 15 are provided on the retaining wall 30 and the existing building 1. The anchor bolt 14 is located at the outer end portion of the floor slab 33 and is driven into the upper surface of the floor slab 33 by being attached before the floor slab 33 is concrete-cast. On the other hand, the anchor bolt 15 is provided at the height of the first floor beam 12 in the outer wall surface 3 of the existing building 1, and is placed on the outer wall surface 3 with a post-construction anchor.

  In step S <b> 2, as shown in FIG. 5, the steel floor unit 40, which is a horizontal restraint material, is installed on the first floor level of the gap space 7 using the existing frame-side bracket 50.

Specifically, first, the existing housing side bracket 50 is attached to the anchor bolt 15.
As shown in FIGS. 6 to 8, the existing housing side bracket 50 has a plate-like joining plate 52 in which a circular bolt hole 51 is formed and extends substantially vertically, and extends substantially horizontally from the upper end of the joining plate 52. A plate-like support plate 53 and a stiffener 54 provided between the joining plate 52 and the support plate 53 are provided.
The existing frame side bracket 50 is fixed by inserting the anchor bolts 15 into the bolt holes 51 of the joining plate 52. Further, a grout material 55 is filled between the existing frame side bracket 50 and the outer wall surface 3 of the existing building 1.

Next, the steel floor unit 40 is installed in the gap space 7 between the retaining wall 30 and the existing housing side bracket 50. A plurality of the steel floor units 40 are arranged along the gap space 7.
As shown in FIGS. 6 to 8, the steel floor unit 40 includes three beam members 41 extending in the length direction of the steel floor unit 40 and arranged substantially parallel to each other, and upper portions of these beam members 41. And a retaining wall side mounting member 43 provided at the end of the beam member 41.

Specifically, the beam member 41 is an H-shaped steel, and the floor member 42 is a steel plate.
The retaining wall side mounting member 43 includes an end plate 44 provided substantially vertically on the end surface of the beam member 41, and a joining plate 45 extending substantially horizontally from the lower end of the end plate 44.
A loose hole 46 extending in the length direction of the steel floor unit 40 is formed in the joining plate 45.

  One end side of the steel floor unit 40 is placed on the support plate 53 of the existing housing side bracket 50 and joined to the support plate 53 with a bolt 56, and the other end side of the steel floor unit 40 is connected to the retaining wall 30. The anchor bolts 14 are inserted into the loose holes 46 of the steel floor unit 40 and fixed.

In step S <b> 3, the temporary support column 60 is installed on the first basement floor of the existing building 1.
As shown in FIG. 9, a temporary support column 60 is installed in the vicinity of the first basement column 11 of the existing building 1. The temporary support column 60 includes a hydraulic jack 61, and by driving the temporary support column 60, the temporary support column 60 temporarily supports the first floor beam 12 from below by applying a reaction force to the first floor 10 of the basement.

In step S4, the stigma portion of the first basement pillar 11 is cut and removed.
As shown in FIG. 9, the underground first-floor pillar 11 is cut and removed along the cutting lines 62 </ b> A and 62 </ b> B. In addition, a reinforcing frame 63 is constructed around the first basement pillar 11.

In step S5, the seismic isolation device 20 is installed at the place where the frame of the first-floor pillar 11 is removed.
As shown in FIG. 10, a lower base isolation base 21 is constructed on the lower part of the first basement column 11 and the base isolation device 20 is installed on the lower base isolation base 21. Subsequently, the upper base isolation base 22 is constructed on the base isolation device 20.

In step S6, the temporary support column 60 and the steel floor unit 40 are removed.
The support of the building body 4 by the temporary support column 60 is released, and then the steel floor unit 40 is removed. Further, the rising portion 34 of the retaining wall 30 is constructed. Thereby, as shown in FIG. 2, the space between the retaining wall 30 and the building body 4 becomes the seismic isolation pit 6.

According to this embodiment, there are the following effects.
(1) The steel floor unit 40 of the present invention can be easily removed simply by loosening the anchor bolt 14 and removing the bolt 56. Since no concrete is used for the horizontal restraint material as in the past, generation of noise at the time of removal can be suppressed, and dismantling is not generated. Accordingly, it becomes easy to attach and remove the horizontal restraint material.
Moreover, since the beam member 41 and the floor member 42 are integrated to form the steel floor unit 40, movement and transportation are facilitated and can be repeatedly used.

(2) The anchor bolt 14 was inserted into the loose hole 46 of the steel floor unit 40 and fixed. Therefore, even if the building body 4 is moved up and down by the jack, the anchor bolt 14 moves inside the loose hole by loosening the bolt or nut of the anchor bolt 14, and the steel floor unit 40 is moved up and down the building body 4. Can be followed.
Moreover, since the steel floor unit 40 and the anchor bolt 14 are joined by the loose hole 46, the construction clearance can be secured and the construction error of the anchor bolt 14 can be absorbed.

[Second Embodiment]
FIG. 11 is an explanatory diagram of a horizontal movement restraining method according to the second embodiment of the present invention.
In the present embodiment, the structure of the retaining wall 30 </ b> A is different from that of the first embodiment, and the floor level of the existing building 1 is lower than the ground surface, so that the floor slab 33 is provided on the horizontal plane at the intermediate height of the vertical wall 32. ing.
In this case, the cutout portion 35 is provided in the joint portion between the upper surface of the floor slab 33 and the vertical wall 32 by punching the vertical wall 32 and placing concrete. And the anchor bolt 14 is provided in this notch part 35, and the steel floor units 40 are attached. After the installation of the seismic isolation device 20 is completed and the steel floor unit 40 is removed, concrete is placed in the notch 35.

  According to the present embodiment, there are the same effects as the above (1) and (2).

  It should be noted that the present invention is not limited to the above-described embodiment, and modifications, improvements, etc. within a scope that can achieve the object of the present invention are included in the present invention.

DESCRIPTION OF SYMBOLS 1 ... Existing building, 3 ... Outer wall surface, 4 ... Building body 5 ... Ground, 6 ... Seismic isolation pit, 7 ... Gap space 10 ... Basement 1st floor, 11 ... Basement 1st floor pillar, 12 ... 1st floor beam, 13 ... 1st floor 14, 15 ... Anchor bolt 20 ... Seismic isolation device, 21 ... Lower base isolation base, 22 ... Upper base isolation base 30, 30A ... Retaining wall, 31 ... Bottom plate, 32 ... Vertical wall, 33 ... Floor slab 34 ... Rising part, 35 ... Notch part 40 ... Steel floor unit, 41 ... Beam member, 42 ... Floor member 43 ... Retaining wall side mounting member, 44 ... End plate, 45 ... Joining plate, 46 ... Loose hole 50 ... Existing bracket side bracket, 51 ... bolt hole, 52 ... joining plate 53 ... support plate, 54 ... stiffener, 55 ... grout material, 56 ... bolt 60 ... temporary support post, 61 ... hydraulic jack, 62A, 62B ... cutting line, 63 ... Reinforcing housing

Claims (2)

A horizontal movement restraint method that restrains the horizontal movement of an existing building when the existing building is seismically isolated,
Constructing a retaining wall outside the existing building and forming a space between the retaining wall and the existing building;
A step of laying a plurality of steel floor units each having a steel beam member and a steel floor member as a horizontal restraint material capable of following up and down movement between the retaining wall and the existing building, A horizontal movement restraining method comprising: An anchor bolt is provided on the upper surface of the retaining wall or a horizontal surface at an intermediate height,
Fixing one end of the steel floor unit to the outer wall of the existing building;
The horizontal movement restraint method according to claim 1, wherein a loose hole extending in a horizontal direction is provided on the other end side of the steel floor unit, and the anchor bolt is inserted into the loose hole.

Images