JP2015143440A - Horizontal force support member and horizontal force support structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a horizontal force bearing member capable of simply constituting a horizontal force bearing structure and capable of shortening a construction period, and the horizontal force bearing structure using the horizontal force bearing member.SOLUTION: A plate-like horizontal force bearing member 11, which is installed between an existing building under base-isolation repair work and an earth retaining wall 10 formed around the existing building, transfers a horizontal force, which acts on the existing building 2, to the earth retaining wall 10. A recess or a protrusion in a plan view is formed on the earth retaining wall 10. The horizontal force bearing member 11 is engaged with the recess or the protrusion and fixed to the earth retaining wall 10.

Description

  The present invention relates to a horizontal force support member and a horizontal force support structure used as an earthquake countermeasure work during seismic isolation repair work for an existing building.

For the purpose of seismic isolation of existing buildings, seismic isolation devices may be installed between the superstructure and the foundation structure. The seismic isolation existing building can reduce the horizontal force during the earthquake input to the superstructure, and avoid the resonance phenomenon by increasing the natural period of the superstructure.
For such a seismic isolation device, for example, a laminated rubber or a sliding bearing is adopted.

  Seismic isolation repair work for existing buildings involves excavating below the existing building, forming a foundation slab below the existing building, and supporting the existing building with the support provided on the foundation slab. (See Patent Document 1).

During seismic isolation repair of existing buildings, it is desirable to provide a horizontal force support structure in case an earthquake occurs.
As the horizontal force support structure, for example, a beam is installed between an existing building and a surrounding retaining wall, or between the upper structure and the surrounding retaining wall as shown in Patent Document 2. There are some that lay a temporary slab horizontally.

JP-A-08-284177 JP 2001-132268 A

  When a beam is used as the horizontal force support structure, it is necessary to firmly fix the beam to the dome and the existing building in order to ensure the transmission performance of the horizontal force. It takes time to remove.

  In addition, when temporary slabs are used, anchors for fixing the temporary slabs need to be embedded in the retaining walls around the existing building, so it is necessary to construct the retaining walls in advance, which hinders shortening the construction period. There was a case.

In conventional mountain retaining walls (main pile side sheet piles and sheet piles) that have a supporting structure (cutting beam, etc.) that supports horizontal force, concrete or metal is placed between the retaining wall (support pile, etc.). In some cases, a backing material made of steel is attached to ensure that the horizontal force transmission between the mountain retaining wall and the support works is reliable and even, so that the ground does not collapse.
However, the effect of the backing material is effective in the vertical direction of the retaining wall, but the horizontal force transmission effect in the direction of the retaining wall surface is insufficient.

On the other hand, in cases where seismic isolation of an existing building is expected to have a large load in the horizontal direction of the mountain wall during an earthquake and high safety is required, which is different from that of a new building, horizontal force in the horizontal direction of the mountain wall is required. It is necessary to communicate with certainty.
For this reason, methods such as hitting studs on the wall surface of the mountain retaining wall or the surface of the flank, or fixing the mountain retaining wall and supporting work (bumping material, etc.) with bolts are possible. It was difficult to support a large load in the direction of the retaining wall with studs or bolts.

  From such a viewpoint, it is an object of the present invention to propose a horizontal force support member and a horizontal force support structure that can easily constitute a horizontal force support structure and that can shorten the work period. To do.

  In order to solve the above-mentioned problems, the present invention provides a horizontal force acting on the existing building, which is installed between an existing building under seismic isolation repair work and a mountain retaining wall formed around the existing building. A plate-shaped horizontal force support member that transmits to the mountain retaining wall, wherein the mountain retaining wall is formed with a recess or a protrusion in plan view, and the horizontal force support member is the recess or the protrusion And is fixed to the mountain retaining wall.

According to such a horizontal force support member, the horizontal force transmission performance can be ensured by being engaged with the mountain retaining wall, so that the horizontal force support structure can be configured easily.
Moreover, since the said horizontal force support member is plate shape, it is excellent in the horizontal force transmission performance compared with the conventional cut beam.

  Furthermore, since the horizontal force support member is engaged with the steel sheet pile, it can be installed without waiting for the completion of the main retaining wall constructed around the existing building. That is, if the horizontal force support member of the present invention is used, the construction period of the seismic isolation work can be shortened.

The horizontal force support member removably connects the base fixed to the existing building, the main body installed between the base and the mountain retaining wall, and the base and the main body. If the convex part or recessed part engaged with the recessed part or convex part of the said mountain retaining wall is formed in the said main-body part, installation and removal work will become easier.
In addition, the said mountain retaining wall may be comprised with the steel sheet pile.

  Further, the horizontal force support structure of the present invention restrains the displacement of the existing building during the seismic isolation repair work, and between the existing building and the mountain wall formed around the existing building. A plurality of the horizontal force support members are arranged side by side in the horizontal direction.

  According to such a horizontal force support structure, the horizontal force acting on the existing building under the seismic isolation work is effectively removed without waiting for the completion of the retaining wall built around the existing building. ).

  According to the horizontal force support member and the horizontal force support structure of the present invention, the horizontal force support structure can be easily configured, and the construction period can be shortened.

It is sectional drawing which shows the installation condition of the horizontal force support structure of this embodiment. It is a top view which shows the horizontal force support structure of FIG. It is sectional drawing which shows the horizontal force support structure of FIG. It is sectional drawing which shows the operation | work condition of the construction method of a horizontal force support structure, Comprising: (a) is before construction, (b) and (c) are excavation conditions. (A)-(c) is the plane sectional view and longitudinal section which show the construction procedure of a horizontal force support structure. (A) And (b) is sectional drawing which shows the operation | work condition of the construction method of the horizontal force support structure following (c) of FIG.

  In the present embodiment, for the purpose of seismic isolation of an existing building, the displacement of the existing building during the seismic isolation repair work is constrained when an isolation device is interposed between the existing building and the new foundation structure. A horizontal force support structure and a horizontal force support member used therefor will be described.

  As shown in FIG. 1, the horizontal force support structure 1 of the present embodiment includes a mountain retaining wall 10 formed around an existing building 2, and a plate-like wall installed between the mountain retaining wall 10 and the existing building 2. A horizontal force support member 11.

The mountain retaining wall 10 is formed of steel sheet piles (sheet piles) placed around the existing building 2.
As shown in FIG. 2, a U-shaped steel sheet pile is used for the steel sheet pile constituting the mountain retaining wall 10. The mountain retaining wall 10 has irregularities (concave portions and convex portions) formed on the surface thereof by connecting the steel sheet piles in a corrugated manner. In addition, the steel sheet pile which comprises the mountain retaining wall 10 is not limited to a U-shaped steel sheet pile, For example, a hat-shaped steel sheet pile may be sufficient. Moreover, the mountain retaining wall 10 does not necessarily need to be a steel sheet pile.

  The mountain retaining wall 10 of the present embodiment is formed with the upper end portion protruding from the ground surface. The mountain retaining wall 10 is a so-called temporary structure and is removed after the seismic isolation repair work. The mountain retaining wall 10 may be left after the seismic isolation repair work, for example, as part of the retaining wall 3 (use of the main wall).

  The horizontal force support member 11 is horizontally mounted between the mountain retaining wall 10 and the existing building 2 and acts on the existing building 2 during the seismic isolation repair work (the horizontal force in the inner and outer directions of the mountain retaining wall 10 and the horizontal force). The horizontal force in the direction along the mountain retaining wall 10) is transmitted to the ground around the existing building 2 (the mountain retaining wall 10).

As shown in FIGS. 2 and 3, the horizontal force support member 11 includes a main body portion 12, a base portion 13, and a connecting portion 14.
A plurality of horizontal force support members 11 are arranged in parallel along the outer surface of the existing building 2 at a predetermined interval.

The main body portion 12 is a precast concrete plate disposed between the mountain retaining wall 10 and the base portion 13.
As shown in FIG. 2, the main body portion 12 is formed with a convex portion 15 protruding toward the mountain retaining wall 10 side.

  The convex portion 15 is formed in a shape that can be inserted (engaged) into the concave portion 10 a of the mountain retaining wall 10. The convex portion 15 is provided at the center in the width direction of the main body portion 12 and has a trapezoidal shape such as a plan view.

Moreover, the convex part 15 has a larger thickness than the main-body part 12 (parts other than the convex part 15), as shown in FIG.
In addition, the convex part 15 should just be the insertion (engagement) to the recessed part 10a of the mountain retaining wall 10, and the shape and arrangement | positioning of the convex part 15 are not limited.

  As shown in FIG. 2, the gap between the main body 12 and the mountain retaining wall 10 is filled with a filler 16 such as mortar. In addition, the material which comprises the filler 16 will not be limited if axial force transmission between the pile 10 and the main-body part 12 is possible, For example, grout and concrete may be sufficient.

  As shown in FIG. 1, the main body portion 12 of the present embodiment constitutes a part of the retaining wall 3 constructed along the mountain retaining wall 10. That is, the retaining wall 3 is formed in a state where the main body portion 12 of the horizontal force support member 11 is wound.

  A plurality of through holes 12a, 12a,... For inserting the reinforcing bars (main bars) of the retaining wall 3 are formed at the end of the main body 12 on the mountain retaining wall 10 side.

As shown in FIG. 3, the through holes 12a are arranged in two rows. The through hole 12a on the mountain retaining wall 10 side is formed vertically, and the through hole 12a on the existing building 2 side is inclined.
Note that the number, arrangement, inclination angle, and the like of the through holes 12 a are not limited, and may be set as appropriate according to the reinforcement of the retaining wall 3.

  Further, bolt holes 12b, 12b,... For joining to the connecting portion 14 are formed at the end of the main body 12 on the existing building 2 side.

  The bolt hole 12b of this embodiment is an insert for screwing a bolt. In addition, the structure of the bolt hole 12b is not limited, For example, the through-hole which penetrates a volt | bolt may be sufficient. Further, the bolt hole 12b may be formed as necessary, and may be omitted depending on the joining form of the main body portion 12 and the connecting portion 14.

The base 13 is fixed to the side surface of the existing building 2 via a plurality of anchors 13a, 13a,.
The base portion 13 is made of H-shaped steel and is installed sideways along the side surface of the existing building 2.
In addition, the material which comprises the base 13 is not limited to H-shaped steel, For example, groove type steel and L-shaped steel may be sufficient.

The main body portion 12 and the base portion 13 are detachably connected via a connecting portion 14.
A gap is formed between the main body portion 12 and the base portion 13, and the connecting portion 14 covers the gap from above and below.

  As shown in FIG. 3, the connecting portion 14 fixes a pair of connecting plates 14 a and 14 a horizontally mounted so as to sandwich the gap between the main body portion 12 and the base portion 13 from above and below, and the pair of connecting plates 14 a and 14 a. It comprises bolts 14b and 14c. In addition, the structure of the connection part 14 is not limited, For example, it replaces with the connection board 14a and may employ | adopt a frame-shaped member.

  The connecting plate 14a is made of a steel plate. The connecting plate 14a has a plurality of through holes through which the bolts 14b and 14c are inserted.

  The bolt 14b on the main body 12 side is inserted through the through hole of the connecting plate 14a and screwed into the bolt hole 12b of the main body 12 to connect the main body 12 and the connecting plate 14a.

  On the other hand, the bolts 14c on the base 13 side are inserted through the through holes of the upper and lower connecting plates 14a, 14a and are inserted into the base 13. A pair of connecting plates 14a, 14a and the base portion 13 are connected by screwing nuts to both ends of the bolt 14c.

  A gap 16 between the base 13 and the existing building 2 is filled with a filler 16 such as mortar. In addition, the material which comprises the filler 16 will not be limited if axial force transmission between the pile 10 and the main-body part 12 is possible, For example, grout and concrete may be sufficient.

In the present embodiment, a jack 17 is interposed in the gap between the main body portion 12 and the base portion 13.
The jack 17 is interposed between the main body portion 12 and the base portion 13, thereby enabling transmission of axial force between the main body portion 12 and the base portion 13.

  In addition, it is good also as a structure which transmits axial force between the main-body part 12 and the base 13 by making the main-body part 12 and the base 13 contact | abut directly. Further, as long as the axial force can be transmitted between the main body portion 12 and the base portion 13, another member may be provided instead of the jack 17.

Next, the construction method of the seismic isolation repair work using the horizontal force support structure of this embodiment will be described.
The seismic isolation repair construction method includes a mountain retaining process, a first excavation process, an installation process, a second excavation process, a seismic isolation process, a retaining wall process, and a removal process.

The mountain retaining step is a step of forming the mountain retaining wall 10 along the outer surface of the existing building 2 as shown in FIGS.
In the present embodiment, the mountain retaining wall 10 is formed by driving (pressing) a steel sheet pile from the ground at a position spaced apart from the existing building 2.

The first excavation step is a step of excavating between the mountain retaining wall 10 and the existing building 2 as shown in FIG.
In the first excavation process, excavation is performed until the foundation 2a of the existing building 2 is exposed. In the first excavation process, a cut beam 10b is installed between the mountain retaining wall 10 and the existing building 2 as necessary as the excavation progresses.

The installation step is a step of forming the horizontal force support structure 1 by installing the horizontal force support member 11 between the mountain retaining wall 10 and the existing building 2.
In this embodiment, although the horizontal force support member 11 is installed in the lower end part (lower end part of the base part 2a) of the existing building 2, the installation depth of the horizontal force support member 11 is not limited.

  In the installation step, first, as shown in FIG. 5A, the bracket 18 is installed on the side surface of the existing building 2, and the temporary support member 19 is installed along the surface of the mountain retaining wall 10.

  The temporary support member 19 is horizontally mounted on brackets 19 a and 19 a fixed to the surface of the mountain retaining wall 10. In addition, the fixing method of the temporary receiving material 19 is not limited. Further, the configuration of the temporary support member 19 is not limited.

  Next, as shown in FIG. 5B, the base 13 is placed on the bracket 18 and the base 13 is fixed to the existing building 2 via the anchor 13a.

After the base 13 is installed, the main body 12 is installed.
The main body portion 12 is installed in a state where the convex portion 15 is inserted into the concave portion 10 a of the mountain retaining wall 10.

  The end of the main body portion 12 on the existing building 2 side is fixed to the base portion 13 via the connecting portion 14. The end of the main body 12 on the mountain retaining wall 10 side is fixed to the temporary support member 19. The main body 2 is fixed to the temporary support member 19 with a bolt (not shown).

  When the main body portion 12 and the base portion 13 are installed, as shown in FIG. 5C, the filler 16 is filled into the gap between the main body portion 12 and the mountain retaining wall 10 and the gap between the base portion 13 and the existing building 2.

  When the filler 16 is cured, a jack 17 is interposed between the main body 12 and the base 13, and the jack 17 is extended to introduce an axial force into the horizontal force support member 10.

A 2nd excavation process is a process of excavating the lower part of the existing building 2 (foundation part 2a), as shown to (c) of FIG. 4, after forming the horizontal force support structure 1. FIG.
In the drawings, reference numeral 2b denotes an existing pile.

  The seismic isolation process is a process of installing the seismic isolation device 4 below the existing building 2 as shown in FIG.

  In the seismic isolation process, first, a new steel pipe pile 2c is added. In addition, the newly installed steel pipe pile 2c should just be extended as needed, and when a sufficient supporting force can be ensured by the foundation ground or the existing pile 2b, it is not necessary to add.

  Next, the foundation slab 2d is constructed in the space formed below the existing building 2. The foundation slab 2c is constructed by placing concrete in a state where the exposed portion of the existing pile 2b and the head of the newly installed steel pipe pile 2c are involved.

When the foundation slab 2d is constructed, a temporary support member (not shown) such as a jack is interposed between the foundation portion 2a and the newly installed steel pipe pile 2c, and the existing building 2 is temporarily received.
Then, the existing pile 2b arrange | positioned in the position where the seismic isolation apparatus 4 is installed is cut | disconnected. That is, the existing building 2 is in a state of being supported by the remaining existing pile 2b (the uncut existing pile 2b) and the new steel pipe pile 2c until the installation of the seismic isolation device 4 is completed.

Next, the seismic isolation device 4 is installed between the foundation slab 2c and the existing building 2 (foundation part 2a).
The seismic isolation device 4 of this embodiment includes a laminated rubber bearing 41 and an oil damper 42. In addition, the structure of the seismic isolation apparatus 4 is not limited.
After installing the seismic isolation device 4, the temporary support member is removed and the remaining existing pile 2b is cut.

The retaining wall process is a process of constructing the retaining wall 3 along the mountain retaining wall 10 (see FIG. 1).
The retaining wall 3 is constructed in a state in which the main body 12 of the horizontal force support member 11 is rolled up.
The construction of the retaining wall 3 may be performed simultaneously with the installation of the seismic isolation device 4 or may be performed before or after the installation of the seismic isolation device 4.

A removal process is a process of removing the base wall 13 and separating the existing building 2 as shown in FIG. 6B.
At this time, the mountain retaining wall 10 is also removed.

In addition, the clearance required for a seismic isolation function is ensured between the main-body part 12 (retaining wall 3) after removing the base 13, and the existing building 2. As shown in FIG.
In the present embodiment, the case where the seismic isolation repair work is completed with a part of the main body 12 protruding from the retaining wall 3 is described, but the main body 12 does not need to protrude from the retaining wall 3.

As mentioned above, according to the horizontal force support member 11 and the horizontal force support structure 1 of this embodiment, since it can install easily, the influence on the construction period of a seismic isolation repair work can be suppressed to the minimum.
Moreover, even if an earthquake occurs during the seismic isolation renovation work, the horizontal force acting on the existing building 1 can be transmitted to the surrounding ground, so that safety can be ensured.

  Further, by engaging the convex portion 15 with the mountain retaining wall 10, the horizontal force (the horizontal force in the direction along the wall surface of the mountain retaining wall 10) is effectively transmitted to the surrounding natural ground (the mountain retaining wall). Can do. Therefore, a highly reliable horizontal force support structure 1 can be configured.

Moreover, since the horizontal force support member 11 is engaged with the steel sheet pile (mountain wall 10), it can be installed without waiting for the completion of the main retaining wall constructed around the existing building 2. it can. That is, the installation and dismantling time of the horizontal force support structure 1 does not depend on the process of the retaining wall 3.
In addition, since the plate-like horizontal force support member 10 having excellent horizontal force transmission performance is used, the reliability is high, and even if the seismic isolation repair work for an existing building is in operation over a long period of time, Excellent safety.

Moreover, since the main-body part 11 is comprised by the precast concrete plate, it is left on the concrete retaining wall 3, and the effort which is required for removal of the horizontal force support member 11 by using it as a part of retaining wall 3 is required. Can be omitted.
Therefore, if the horizontal force support member 11 of the present embodiment is used, it is possible to perform the retaining wall 3 in parallel with the seismic isolation work of the existing building 2, and thus the construction period can be shortened. It is.

Moreover, since the main-body part 12 and the base 13 are connected so that attachment or detachment is possible through the connection part 14, the horizontal force support member 11 is easy to install and remove.
That is, since the horizontal force support member 11 can release the connection state between the mountain tower 10 and the existing building 2 only by removing the base portion 13, the labor required for removing the horizontal force support structure 1 can also be reduced. Can do.

  Note that the horizontal force support structure 1 can be used even when a part of the existing building 2 is subjected to seismic isolation repair work depending on the scale or site of the building.

  Since the main body portion 12 is formed with a plurality of through holes 12a, 12a,... For inserting the reinforcing bars of the retaining wall 3, the reinforcing bars can be positioned using the through holes 12a, 12a,. Is possible.

The embodiment of the present invention has been described above. However, the present invention is not limited to the above-described embodiment, and the above-described components can be appropriately changed without departing from the spirit of the present invention.
For example, in the above-described embodiment, the case where the main body portion is precast concrete has been described. However, the configuration of the main body portion is not limited, and may be a steel member, for example.
Moreover, although the said embodiment demonstrated the case where the convex part was formed in the main-body part, the recessed part engaged with the convex part of a mountain retaining wall may be formed in the main-body part.

Moreover, although the said embodiment demonstrated the case where the seismic isolation repair work was performed about the existing building which has a pile foundation structure, the foundation structure of an existing building is not limited.
Moreover, although the said embodiment demonstrated the case where a mountain retaining wall was removed after construction of a retaining wall, it is not necessary to remove a mountain retaining wall necessarily.

DESCRIPTION OF SYMBOLS 1 Horizontal force support structure 2 Existing building 3 Retaining wall 4 Seismic isolation device 10 Yamadome wall 10a Concave part 11 Horizontal force support member 12 Main body part 13 Base part 14 Connection part 15 Convex part

Claims (4)

A plate-like horizontal force that is installed between an existing building under seismic isolation work and a mountain wall formed around the existing building, and transmits the horizontal force acting on the existing building to the mountain wall A support member,
The mountain retaining wall is formed with a concave portion or a convex portion in plan view,
The horizontal force support member is engaged with the concave portion or the convex portion and fixed to the mountain retaining wall. A base fixed to the existing building;
A main body installed between the base and the mountain retaining wall;
A connecting portion that removably connects the base portion and the main body portion;
The horizontal force support member according to claim 1, wherein a convex portion or a concave portion that engages with the concave portion or the convex portion of the mountain retaining wall is formed in the main body portion.   The horizontal force support material according to claim 1, wherein the mountain retaining wall is made of a steel sheet pile. A horizontal force support structure that restrains the displacement of existing buildings during seismic isolation repair work,
The horizontal force support member according to any one of claims 1 to 3 is spaced apart in a horizontal direction between the existing building and a mountain retaining wall formed around the existing building. A horizontal force support structure characterized by being arranged in parallel.

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