JP2018119335A - Horizontal resistance structure of existing building and construction method of horizontal resistance structure of existing building - Google Patents

Abstract

The present invention provides a horizontal resistance structure for an existing building and a method for constructing the horizontal resistance structure for an existing building, which does not impede the loading and unloading of construction materials. [Solution] A horizontal resistance structure 100 for an existing building is a horizontal resistance structure that supports the existing building A when the seismic isolation device 9 is installed directly under the existing building A, and is placed near the seismic isolation device 9. a lower pile 1 that is supported by the ground C and extends upward; an upper pile 2 that is placed above facing the lower pile 1 and supported by the existing building A and extends downward; It is characterized by comprising a joined steel pipe 3 in which the upper part of the side pile 1 and the lower part of the upper pile 2 are arranged, and mortar 4 filled inside the joined steel pipe 3. [Selection diagram] Figure 1

Description

  The present invention relates to a horizontal resistance structure of an existing building and a construction method of a horizontal resistance structure of an existing building.

  Conventionally, seismic isolation retrofit work has been carried out by installing seismic isolation layers on the foundations and intermediate floors of existing buildings. For example, there is a construction method of excavating the ground directly under the foundation of an existing building, placing multiple temporary steel pipe piles, and temporarily installing the seismic isolation device directly under the foundation while temporarily supporting the existing building with steel pipe piles. It is known (see Patent Document 1).

  Since the ground is excavated during the seismic isolation work, the horizontal resistance due to friction between the existing building and the ground decreases. For earthquake countermeasures, it is necessary to fix the existing building in the foundation fixed state, and there are cases where horizontal resistance is secured by installing steel plate walls and braces in the excavation space.

Japanese Patent Application Laid-Open No. 2006-11520

  However, when a steel plate wall or brace is installed in the excavation space, there is a problem in that the excavated earth and sand and the construction materials such as seismic isolation devices are hindered.

  Then, this invention is made | formed in view of the said situation, and provides the construction method of the horizontal resistance structure of the existing building which does not interfere with carrying in / out of construction materials etc., and the horizontal resistance structure of the existing building.

In order to achieve the above object, the present invention employs the following means.
That is, the horizontal resistance structure of the existing building according to the present invention is a horizontal resistance structure that supports the existing building when the seismic isolation device is installed in the excavation space formed immediately below the existing building, A lower pile located near the device, supported by the ground and extending upward; an upper pile opposed to the lower pile; supported by the existing building; and extended downward; And a mortar filled inside the joint steel pipe, wherein the upper part of the lower pile and the lower part of the upper pile are arranged.

In the horizontal resistance structure of the existing building configured as described above, a bonded steel pipe is disposed outside the upper portion of the lower pile and the lower portion of the upper pile. The inside of the joining steel pipe is filled with mortar. Therefore, since the lower pile supported by the ground and extending upward and the upper pile supported by the existing building and connected downward by the hardened mortar are connected, the horizontal resistance of the existing building can be ensured.
It is the structure which connects a lower pile and an upper pile to an up-down direction, and since a steel plate wall, a brace, etc. are not installed in the excavation space conventionally, it does not become the hindrance of carrying in / out of construction materials etc.

  Moreover, it is preferable that the horizontal resistance structure of the existing building which concerns on this invention is provided with the 1st protrusion part which protrudes toward the inner side at the inner surface of the said joining steel pipe.

  In the horizontal resistance structure of the existing building thus configured, the inner surface of the bonded steel pipe is provided with a first protruding portion that protrudes inward, and the first protruding portion is embedded in the mortar. Dropping of the steel pipe is suppressed.

  Moreover, the horizontal resistance structure of the existing building which concerns on this invention is provided with the 2nd protrusion part which protrudes outward on the outer surface of at least any one of the said lower pile and the said upper pile, said 1st The protrusion may be disposed above the second protrusion.

  In the horizontal resistance structure of the existing building thus configured, a second projecting portion projecting outward is provided on the outer surface of at least one of the lower pile and the upper pile, and is provided on the bonded steel pipe. The first protrusion is disposed above the second protrusion. Therefore, the second protrusion provided on at least one of the lower pile and the upper pile supports the cured mortar, and the first protrusion of the bonded steel pipe receives a reaction force from the second protrusion via the mortar. Therefore, the joining steel pipe is further suppressed from dropping off.

  Moreover, in the horizontal resistance structure of the existing building which concerns on this invention, the length of the part which overlaps with each up-down direction of each of the said joining steel pipe, the said lower pile, and the said upper pile is 1 / of the diameter of the said joining steel pipe. Two or more may be sufficient.

  In the horizontal resistance structure of the existing building configured as described above, the length of the overlapping portion of each of the bonded steel pipe, the lower pile, and the upper pile in the vertical direction is 1/2 or more of the diameter of the bonded steel pipe. Therefore, the horizontal resistance of the existing building can be reliably ensured.

  Further, the construction method of the horizontal resistance structure of the existing building according to the present invention is a construction method of the horizontal resistance structure of the existing building that supports the existing building when installing the seismic isolation device directly under the existing building, An excavation process for excavating directly under an existing building, a lower pile placing process for placing a lower pile on the ground facing the excavation space formed in the excavation process, and the lower pile in the existing building An upper pile installation step of installing an upper pile at a position; a jack installation step of installing a jack at an upper end portion of the lower pile; and supporting the lower end portion of the upper pile with the jack; and the lower pile in the excavation space A seismic isolation device installation step for installing a seismic isolation device in the vicinity of the side pile and the upper pile, a seismic isolation device support step for supporting the existing building with the seismic isolation device by lowering the jack, and the jack Jack removal process to remove A bonded steel pipe installation step in which a bonded steel pipe is installed apart from the outer surface of the upper pile and the outer surface of the lower pile on the outer periphery of the lower part of the upper pile and the upper part of the lower pile; and inside the bonded steel pipe And a mortar filling step for filling the mortar.

In the construction method of the horizontal resistance structure of the existing building configured as described above, a bonded steel pipe is disposed outside the upper portion of the lower pile and the lower portion of the upper pile. The inside of the joining steel pipe is filled with mortar. Therefore, since the lower pile supported by the ground and the upper pile provided in the existing building are connected by the cured mortar, the horizontal resistance of the existing building can be ensured.
It is the structure which connects a lower pile and an upper pile to an up-down direction, and since a steel plate wall, a brace, etc. are not installed in the excavation space conventionally, it does not become the hindrance of carrying in / out of construction materials etc.

  Moreover, the construction method of the horizontal resistance structure of the existing building which concerns on this invention has previously arrange | positioned the said joining steel pipe in the outer side of the said lower pile, and in the said joining steel pipe installation process, pulls up the said joining steel pipe, and it is inside. It is preferable to install in the position where the lower part of the said upper pile and the upper part of the said lower pile are arrange | positioned.

  In the construction method of the horizontal resistance structure of the existing building constructed in this way, if the bonded steel pipe is arranged in advance outside the lower pile and the bonded steel pipe is pulled up, the lower part of the upper pile and the lower pile are built inside. Since it is installed at the position where the upper part is placed, workability is good.

  According to the horizontal resistance structure of an existing building and the method of constructing the horizontal resistance structure of an existing building according to the present invention, it does not hinder the carrying in and out of construction materials and the like.

It is a vertical sectional view showing a horizontal resistance structure of an existing building according to an embodiment of the present invention. It is the X section enlarged view of FIG. It is a figure which shows the construction method of the horizontal resistance structure of the existing building which concerns on one Embodiment of this invention, and is a figure which shows a jack installation process. It is a figure which shows the construction method of the horizontal resistance structure of the existing building which concerns on one Embodiment of this invention, and is a figure which shows a mortar filling process. It is a figure which shows the experimental apparatus performed using the horizontal resistance structure of the existing building which concerns on one Embodiment of this invention. It is a figure which shows the experimental result performed using the horizontal resistance structure of the existing building which concerns on one Embodiment of this invention.

A horizontal resistance structure of an existing building and a method of constructing a horizontal resistance structure of an existing building according to an embodiment of the present invention will be described with reference to the drawings.
First, the horizontal resistance structure of an existing building will be described. The horizontal resistance structure of an existing building is employed, for example, during seismic isolation retrofit work in which a base isolation device is installed by excavating the ground directly below the foundation (foundation) of the existing building.
FIG. 1 is a vertical sectional view showing a horizontal resistance structure of an existing building according to an embodiment of the present invention. In FIG. 1, the upper pile and the lower pile are shown as a front view without being cut.
As shown in FIG. 1, in the existing building A, a slab D is excavated downward from the foundation plate B, a mat slab D is installed along the ground C, and a reinforcing slab E is installed along the lower surface of the foundation plate B. The horizontal resistance structure 100 of the existing building A is installed in the vicinity of the seismic isolation device 9 below the existing building A. In this embodiment, it is installed on both sides in the horizontal direction across the seismic isolation device 9.

  The horizontal resistance structure 100 of the existing building A includes a lower pile 1, an upper pile 2, a bonded steel pipe 3, and a mortar 4 filled in the bonded steel pipe 3.

  A plurality of lower piles 1 are installed (placed) on the mat slab D and the ground C. In other words, the lower pile 1 passes through the mat slab D, the lower end (not shown) reaches the ground C, and the upper end 1u protrudes upward from the mat slab D. The lower pile 1 may be configured by connecting a plurality of steel pipes. In the present embodiment, the lower pile 1 is connected to a circular steel pipe (cylindrical steel pipe) having a diameter of 457.2 mm, a thickness of 12.7 mm, and a length of about 1000 mm by a mechanical joint or the like (not shown).

  A support plate 11 is provided on the upper end 1 u of the lower pile 1. In the present embodiment, the support plate 11 is formed with a thickness of about 12 mm, for example.

  The upper pile 2 is disposed to face the lower pile 1 vertically above. In other words, the upper pile 2 penetrates the reinforcing slab E, and the lower end 2b protrudes downward from the reinforcing slab E. In this embodiment, the upper pile 2 is, for example, a circular steel pipe having a diameter of 457.2 mm, a thickness of 12.7 mm, and a length of about 1000 mm. In addition, the lower pile 1 and the upper pile 2 are not limited to circular steel pipes, and may be square tubes or the like.

  A support plate 21 is provided at the lower end 2 b of the upper pile 2. In the present embodiment, the support plate 21 is formed with a thickness of about 12 mm, for example. The upper end 2 u of the upper pile 2 is provided with a fixing portion 22 that is fixed to the foundation board B.

FIG. 2 is an enlarged view of a portion X in FIG.
As shown in FIG. 2, the support plate 21 provided on the upper pile 2 has a circular shape in plan view and has a larger diameter than the upper pile 2. In other words, the end portion (second projecting portion) 21e of the support plate 21 projects more outward in the radial direction than the outer surface 2e of the upper pile 2. In the present embodiment, the support plate 21 has a circular shape with a radius 10 mm larger than that of the upper pile 2. In addition, the support plate 11 provided in the lower pile 1 also has the same configuration as the support plate 11, has a circular shape in plan view, and has a larger diameter than the lower pile 1. As shown in FIG. 1, the space | interval (about 300 mm) which can install the temporary jack 6 (refer FIG. 3) mentioned later between the support plate 11 of the lower pile 1 and the support plate 21 of the upper pile 2 is provided more than the space | interval. Just keep it.

  The joined steel pipe 3 is formed larger than the lower pile 1 and the upper pile 2 in plan view. The bonded steel pipe 3 extends from the lower part of the upper pile 2 to the upper part of the lower pile 1 and is arranged so as to cover the lower part of the upper pile 2 and the upper part of the lower pile 1. In this embodiment, the joining steel pipe 3 is a circular steel pipe having a diameter of 558.8 mm, a thickness of 12.7 mm, and a length of about 850 mm, for example. In addition, the joining steel pipe 3 is not restricted to a circular steel pipe, A square pipe may be sufficient. Alternatively, a pair of semicircular steel pipes may be sandwiched between one side and the other side in a plan view of the upper pile 2 and the lower pile 1 and joined together to form a circular steel pipe.

  It is preferable that the length L1, L2 of the part which overlaps with the joining steel pipe 3 and each of the lower pile 1 and the upper pile 2 in the up-down direction is 1/2 or more of the diameter L3 of the joining steel pipe 3. In the present embodiment, the length from the lower end of the bonded steel pipe 3 to the upper surface of the support plate 11 of the lower pile 1 (the length from the upper end of the bonded steel pipe 3 to the lower surface of the support plate 21 of the upper pile 2) is about 275 mm. It is.

  The bonded steel pipe 3 is preferably disposed concentrically with the lower pile 1 and the upper pile 2. The diameter of the bonded steel pipe 3 is preferably about 50 to 100 mm larger than the diameter of the lower pile 1 and the upper pile 2. Although details will be described later, in order to inject the mortar 4 from the gap between the bonded steel pipe 3 and the lower pile 1, between the inner surface 3 i of the bonded steel pipe 3 and the outer surfaces 1 e and 2 e of the lower pile 1 and the upper pile 2. The gap is preferably 10 mm or more.

  As shown in FIG. 2, on the inner surface 3 i of the bonded steel pipe 3, a rib (first protruding portion) 31 that protrudes radially inward and has an annular shape in plan view is formed on the upper end portion. A rib 31 is similarly formed at the lower end of the bonded steel pipe 3. In the present embodiment, the upper rib 31 is positioned slightly below the upper end 3u of the bonded steel pipe 3, and the lower rib 31 is positioned slightly above the lower end. In the present embodiment, the rib 31 protrudes from the inner surface 3 i of the bonded steel pipe 3 to the inside in the radial direction by about 6 mm.

  As shown in FIG. 1, the mortar 4 is filled in the bonded steel pipe 3. In other words, between the inner surface 3i of the bonded steel pipe 3 and the outer surface 2e of the upper pile 2, between the inner surface 3i of the bonded steel pipe 3 and the outer surface 1i of the lower pile 1, and the support plate 21 and the lower pile of the upper pile 2 The space between the support plate 11 is filled with mortar 4.

Next, the construction method of the horizontal resistance structure 100 of the existing building A will be described.
After excavating the outer periphery of the existing building A and installing a beam (not shown), the portion immediately under the existing building A is excavated (excavation process). An excavation space W is formed below the foundation B of the existing building A.

Next, a lower pile driving process is performed.
FIG. 3 is a diagram illustrating a construction method of the horizontal resistance structure 100 of the existing building A, and is a diagram illustrating a jack installation process.
As shown in FIG. 3, the lower pile 1 is press-fitted at a desired location such as directly under the pillar of the existing building A. A hydraulic jack (not shown) is installed on the lower surface of the foundation B (the bottom surface of the existing building A), and the lower pile 1 is press-fitted into the ground C with the hydraulic jack. At this time, the bonded steel pipe 3 is preferably passed through the outside of the upper portion of the lower pile 1. A leveling mortar B1 may be provided on the bottom surface of the foundation B.

Next, an upper pile installation process is performed.
When the press-fitting of the lower pile 1 proceeds, the upper pile 2 is installed at a position facing the lower pile 1 on the lower surface of the foundation board B.

Next, a jack installation process is performed.
A temporary jack 6 is installed on a support plate 11 (see FIG. 1) of the lower pile 1, and the upper pile 2 is temporarily supported by the temporary jack 6.

Next, the seismic isolation device installation process is performed.
FIG. 4 is a diagram illustrating a construction method of the horizontal resistance structure 100 of the existing building A, and is a diagram illustrating a mortar filling process.
As shown in FIG. 4, a mat slab D is installed along the ground C (see FIG. 3). A reinforcing slab E is installed along the lower surface of the foundation B. In the vicinity of the lower pile 1 and the upper pile 2, the lower foundation 91 is provided on the mat slab D, the seismic isolation device 9 is installed on the lower foundation, and the upper foundation 92 is provided on the seismic isolation device 9.

Next, a seismic isolation device support process and a jack removal process are performed.
After the temporary jack 6 is lowered and the existing building A is supported by the seismic isolation device 9, the temporary jack 6 is removed.

Next, a joining steel pipe installation process is performed.
The joining steel pipe 3 is installed so that the lower part of the upper pile 2 and the upper part of the lower pile 1 may be covered. At this time, a locking portion 36 such as a ring shape is provided on the outer surface of the bonded steel pipe 3, the hooked chain block 37 is locked to the locking portion 36, and the chain block 37 is locked to the reinforcing slab E. Then, the bonded steel pipe 3 may be pulled up.
In addition, when the magnitude | size of the joining steel pipe 3 is not larger than the upper pile 2 and the lower pile 1 in planar view, an upper pile is made until the upper pile 2 and the lower pile 1 can be arrange | positioned inside the joining steel pipe 3. 2 and the outer periphery of the lower pile 1 may be cut.

Next, a mortar filling process is performed.
The mortar 4 is filled into the bonded steel pipe 3.
A formwork (not shown) having a shape corresponding to the gap between the inner surface 3 i of the bonded steel pipe 3 and the outer surface 1 e of the lower pile 1 is installed at the lower end of the bonded steel pipe 3. At the upper end of the bonded steel pipe 3, the mortar 4 is injected from the gap between the inner surface 3 i of the bonded steel pipe 3 and the outer surface 2 e of the upper pile 2. When the mortar 4 is cured, the upper pile 2 and the lower pile 1 are connected via the mortar 4.
After installing the seismic isolation device 9 in all the planned installation locations, the lower pile 1 and the upper pile 2 are cut.

(Experimental example)
Next, an experimental example performed on the horizontal resistance structure 100 of the existing building A described above will be described.
In order to confirm the horizontal resistance and joint strength of the horizontal resistance structure 100 of the existing building A, a joint force test using a full-scale specimen was performed. Assuming the case where seismic force acts on the seismic isolation layer, positive and negative alternating shearing force was applied to the specimen, and the mechanical behavior was confirmed.

FIG. 5 is a diagram illustrating an experimental apparatus that was used using the horizontal resistance structure 100 of the existing building A.
FIG. 5 shows the shape of the test specimen and the force device. The test body is a model in which a reinforcing slab, a steel pipe pile (upper pile 2), a steel pipe for joining (joined steel pipe 3) and a filling mortar (mortar 4) (joint part) are modeled and set upside down. . A 355.6 mm × 9.5 mm (STK400) annular steel pipe in cross section was adopted as the steel pipe pile, and a 457.2 mm × 9.5 mm (STK400) annular steel pipe in cross section was adopted as the joining steel pipe. The bonding in the steel, the pre-mix type mortar _{(J 14} funnel test 8 ± 2 seconds, approximately compressive strength 60N / mm ²⁾ was filled with. The applied point was the reaction point position of the moment distribution generated in the steel pipe pile when the upper and lower steel pipe piles were in rigid contact.

FIG. 6 is a diagram illustrating a result of an experiment performed using the horizontal resistance structure 100 of the existing building A.
FIG. 6 shows the relationship between the shear force and the deformation angle of the steel pipe pile obtained from the experimental results. The maximum yield strength of the specimen was determined by local buckling of the steel pipe pile. Local buckling was observed at the embedded end of the steel pipe pile, and the filling mortar in the joint was sound with cracking to the final state. In addition, the initial stiffness of the test specimen has a good correspondence with the calculated value (refer to the steel structure joint design guideline) obtained as an embedded column base steel pipe pile, even if the horizontal resistance structure 100 of the existing building A shown above is not present. Show. As shown in FIG. 6, when the interlayer deformation angle of the seismic isolation layer generated at the time of the earthquake under construction is 1/100 (0.1 rad), one steel pipe pile is formed by the horizontal resistance structure 100 of the existing building A shown above. It was confirmed that a horizontal resistance of 400 kN per hit was obtained. The horizontal resistance can be improved by raising the cross section of the steel pipe pile. For example, if a 457.2 mm × 12.8 mm circular steel pipe is used as the steel pipe pile, a horizontal resistance of 650 kN per steel pipe pile can be secured with an interlayer deformation angle of 1/100 (0.1 rad).
In actual design, the horizontal resistance is calculated by the following procedure. (1) Set the interlayer deformation angle of the seismic isolation layer that occurs during an earthquake. (2) Calculate the rigidity of the steel pipe pile obtained as a buried steel pipe pile without considering the joint. (3) Based on the calculated rigidity, the horizontal resistances for the number of steel pipe piles to which the horizontal resistance structure 100 of the existing building A shown above is applied are totaled.

  In the construction method of the horizontal resistance structure 100 of the existing building A and the horizontal resistance structure 100 of the existing building A configured as described above, the bonded steel pipe 3 is disposed outside the upper portion of the lower pile 1 and the lower portion of the upper pile 2. Has been. The inside of the bonded steel pipe 3 is filled with mortar 4. Therefore, the hardened mortar 4 connects the lower pile 1 supported by the ground C and extending upward and the upper pile 2 supported by the existing building A and extending downward, so that the horizontal resistance of the existing building A is ensured. be able to.

  Moreover, it is the structure which connects the lower pile 1 and the upper pile 2 to an up-down direction, and since a steel plate wall, a brace, etc. are not installed like the past, it does not become the hindrance of carrying in / out of construction materials etc.

  Moreover, since the rib 31 which protrudes toward inward is provided in the inner surface of the joining steel pipe 3, and the rib 31 is embedded in the mortar 4, it is suppressed that the joining steel pipe 3 falls off.

  Moreover, it protruded to the outer side of radial direction rather than the outer surface of the support plate 11 provided in the lower pile 1 and the upper pile 2, and the lower pile 1 and the upper pile 2, and was provided in the upper end part of the joining steel pipe 3. The rib 31 is disposed above the support plate 11. Therefore, the end portion of the support plate 11 supports the cured mortar 4, and the rib 31 of the bonded steel pipe 3 receives a reaction force from the end portion of the support plate 11 through the mortar 4, so that the bonded steel tube 3 falls off. Is further suppressed.

  Moreover, since the length of the part which has overlapped each of the joining steel pipe 3 and the lower pile 1 and the upper pile 2 in the up-down direction is 1/2 or more of the diameter of the joining steel pipe 3, the horizontal resistance of the existing building A Power can be ensured.

  Moreover, if the joining steel pipe 3 is previously arrange | positioned on the outer periphery of the lower pile 1, and if the joining steel pipe 3 is pulled up, it will be installed in the position where the lower part of the upper pile 2 and the upper part of the lower pile 1 are arrange | positioned inside. Therefore, workability is good.

  Moreover, when the upper pile 2 and the lower pile 1 are eccentric in plan view, the upper pile 2 and the lower pile 1 are bolted together in a configuration in which the upper pile 2 and the lower pile 1 are bolted together. Difficult to connect. In this invention, since it is the structure which covers the upper pile 2 and the lower pile 1 with the joining steel pipe 3 larger than the upper pile 2 and the lower pile 1, and fills the inside of the joining steel pipe 3 with the mortar 4, the upper pile 2 Even if the lower pile 1 is eccentric in plan view, it can be constructed as long as it is within the range that can be covered by the bonded steel pipe 3.

  It should be noted that the assembly procedure shown in the above-described embodiment, or the shapes and combinations of the constituent members are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

  For example, in the embodiment described above, the bonded steel pipe 3 is provided with the first protrusion, and the lower pile 1 and the upper pile 2 are provided with the second protrusion, but the present invention is not limited thereto. The first protrusion and the second protrusion may not be provided. Or although the 1st protrusion part is formed in planar view cyclic | annular form, it should just protrude inward from the inner surface of the joining steel pipe 3, and may be formed discontinuously in the circumferential direction.

DESCRIPTION OF SYMBOLS 1 ... Lower pile 2 ... Upper pile 3 ... Joint steel pipe 4 ... Mortar 9 ... Seismic isolation device 11 ... Support plate 21 ... Support plate 21e ... End part of a support plate (2nd protrusion part)
22 ... fixed part 31 ... rib (1st protrusion part)
100 ... Horizontal resistance structure A ... Existing building B ... Foundation plate C ... Ground D ... Mat slab E ... Reinforcement slab W ... Excavation space

Claims (6)

When installing a seismic isolation device directly under an existing building, a horizontal resistance structure that supports the existing building,
A lower pile disposed near the seismic isolation device, supported by the ground and extending upward;
An upper pile disposed above the lower pile and supported by the existing building and extending downward;
A bonded steel pipe that extends in the vertical direction and in which the upper part of the lower pile and the lower part of the upper pile are arranged;
A horizontal resistance structure for an existing building, comprising: a mortar filled in the bonded steel pipe.   The horizontal resistance structure for an existing building according to claim 1, wherein a first projecting portion projecting inward is provided on an inner surface of the bonded steel pipe. On the outer surface of at least one of the lower pile and the upper pile, a second protruding portion that protrudes outward is provided,
The horizontal resistance structure for an existing building according to claim 2, wherein the first protrusion is disposed above the second protrusion.   The length of the part which overlaps with the up-down direction of each of the said joining steel pipe, the said lower pile, and the said upper pile is 1/2 or more of the diameter of the said joining steel pipe, The Claim 1 to 3 characterized by the above-mentioned. The horizontal resistance structure of the existing building as described in any one of. When installing a seismic isolation device directly under an existing building, a method for constructing a horizontal resistance structure of the existing building that supports the existing building,
An excavation process for excavating directly under an existing building;
A lower pile placing step for placing the lower pile on the ground facing the excavation space formed in the excavation step;
An upper pile installation step of installing an upper pile at a position facing the lower pile in the existing building;
A jack is installed at the upper end of the lower pile, and the jack is installed to support the lower end of the upper pile with the jack; and
In the vicinity of the lower pile and the upper pile in the excavation space, a seismic isolation device installation step of installing a seismic isolation device;
A seismic isolation device supporting step of lowering the jack and supporting the existing building with the seismic isolation device;
A jack removal step of removing the jack;
On the outer periphery of the lower portion of the upper pile and the upper portion of the lower pile, a bonded steel pipe installation step of installing a bonded steel pipe separated from the outer surface of the upper pile and the outer surface of the lower pile,
And a mortar filling step of filling the inside of the bonded steel pipe with a mortar. Preliminarily arrange the bonded steel pipe outside the lower pile,
In the said joining steel pipe installation process, the said joining steel pipe is pulled up, and it installs in the position where the lower part of the said upper pile and the upper part of the said lower pile are arrange | positioned inside, The existing building of Claim 5 characterized by the above-mentioned. Construction method of horizontal resistance structure.

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