JP3109877U - Base isolation structure - Google Patents

Abstract

【Task】
To provide a base isolation structure that can efficiently and economically construct a base of a base isolation structure that is used as a foundation of a relatively lightweight building such as a detached house.
[Solution]
It comprises a foundation slab 1 provided on the ground side, a floor slab 3 provided on the building side, and a plurality of seismic isolation devices 2 provided between the foundation slab 1 and the floor slab 3. The base slab 1 and the floor slab 2 are respectively provided with a lower frame 4 and an upper frame 5 made of precast concrete at predetermined intervals in the girder direction and span direction of the building. The lower frame 4 is provided in the foundation slab 1 and the upper frame 5 is provided in part in the floor slab 3. The seismic isolation device 2 is installed between the lower frame 4 and the upper frame 5.
[Selection] Figure 1

Description

  The present invention relates to a base isolation structure used for the foundation of a relatively light building, and is mainly used as the foundation of a detached house.

  As a base of the base isolation structure, for example, as illustrated in FIG. 6, a building 20 that is built on the ground and a base 21 that supports the building 20 are separated from each other, and a building 20 as a base isolation device 22 is provided between the base 21 and the building 20. The laminated rubber that transmits the load of the earth to the base 21 side and converts the violent shaking at the time of the earthquake into the slow horizontal shaking, and by absorbing the energy of the shaking, gradually reduces the horizontal shaking width. There is known a foundation in which an attenuation device that quickly attenuates shaking is installed.

In this case, both the foundation 21 and the floor slab of the building 20 are constructed by cast-in-place concrete, and a block-shaped lower frame 23 and an upper frame 24 are respectively provided at positions where the seismic isolation device 22 is installed. The mounts 23 and 24 are also constructed by cast-in-place concrete.
JP 2002-356948 A

  However, if the lower pedestal 23 and the upper pedestal 24 are constructed by cast-in-place concrete, it is necessary to assemble and remove the formwork for each gantry, so that much work is required to assemble and remove the formwork. Since the reinforcement work and the placement of concrete are forced in a very narrow space, the work is not only very troublesome, but the surroundings of the placed concrete are bad, and there is a possibility that the quality may be deteriorated.

  In particular, in the case of a relatively light-weight building such as a detached house, it is not only a large seismic force but also a relatively large amount of wind, etc., that many small seismic isolation devices 22 are installed due to the light weight of the building itself. It is known that it can efficiently absorb vibrations caused by a small external force. In addition to the original seismic isolation devices such as laminated rubber, the pedestals 23 and 24 are used as pedestals for installing bearing members that receive upper loads during construction. Since it is also used, many tend to be provided.

  For this reason, it has been desired to develop a seismic isolation foundation that can construct the above-mentioned frame extremely efficiently and economically.

  The present invention has been made to solve the above problems, and provides a base isolation structure capable of efficiently and economically constructing the base of a base isolation structure used for a relatively lightweight building foundation. Objective.

  The base isolation structure according to claim 1 includes a foundation slab provided on the ground side, a floor slab provided on the building side, and a plurality of seismic isolation devices provided between the foundation slab and the floor slab. In the base-isolated base structure, a lower frame and an upper frame made of precast concrete are respectively provided on the foundation slab and the floor slab at predetermined intervals in the direction of the building and in the span direction, and the lower frame is placed in the foundation slab. The upper frame is provided by being partially embedded in the floor slab, and the seismic isolation device is provided between the lower frame and the upper frame.

  In the present invention, the lower frame and the upper frame for installing the seismic isolation device are all made of precast concrete material, thereby eliminating the formwork and rebar construction necessary to install these frames. This makes it possible to greatly reduce the labor and efficiency of on-site construction.

  The lower frame and the upper frame in this case are not particularly limited in terms of shape, but for example, a flat rectangular shape or a circular shape can be considered. Moreover, it can also be set as a perfect non-strength structure by forming with fiber reinforced concrete.

  The present invention mainly targets the foundation of a detached house. However, if the long-term load per seismic isolation device is about 3 tons, a three-story, steel-framed building is suitable for a wooden building. For example, it can be used for two-story buildings and one-story buildings for RC and block structures.

  The base-isolated base structure according to claim 2 is the base-isolated base structure according to claim 1, wherein the floor slab of the building lays a plurality of deck plates between receiving members spanned between the plurality of upper mounts, It is formed by placing concrete on the deck plate.

  In particular, the present invention eliminates the work of removing the floor formwork by using the deck plate as the floor formwork of the floor slab, and further improves the labor saving and efficiency of on-site construction.

  In addition, by using the deck plate in this case as a structural material for the floor slab, it is possible to save slab reinforcement and to achieve economic efficiency. The receiving member may be a shape steel such as an angle steel or a grooved steel.

  The base-isolated base structure according to claim 3 is the base-isolated base structure according to claim 1 or 2, wherein the lower end of the lower frame is formed so as to gradually become smaller in diameter toward the lower end, and a plurality of horizontal adjustment bolts Are provided at predetermined intervals in the circumferential direction.

  In this invention, the lower frame is shaped to tilt in any direction, and a plurality of horizontal adjustment bolts are attached to the outer periphery, so that the horizontal level of the lower frame can be easily adjusted. be able to.

  As the shape of the lower end portion of the lower pedestal, for example, a quadrangular pyramid shape is possible for a planar rectangular lower pedestal, and a conical shape is conceivable for a planar circular lower pedestal.

  In addition, as a mounting mode of the leveling bolt, for example, a screw such as a wrench is attached from the side or the upper side of the lower frame when the leveling of the lower frame is performed by screwing it to an insert nut embedded vertically in the concrete of the lower frame. The method may be such as turning the horizontal adjustment bolt to change the length of the downward projection as appropriate.

  The base isolation structure according to claim 4 is the base isolation structure according to any one of claims 1 to 3, wherein the temporary base is detachably fixed to the lower frame and the upper frame between the lower frame and the upper frame. A fixing member is attached.

According to the present invention, the lower frame and the upper frame are assembled together with the seismic isolation device in advance by a temporary fixing member, so that these members can be transported and installed at the same time.
In this case, the temporary fixing member can be a plate material, or a shape steel such as angle steel or channel steel, and as a method of detachably fixing the temporary fixing member to the lower frame and the upper frame, For example, a fixing bolt may be fastened to an insert nut embedded in the lower frame and the upper frame and the bolts may be fastened.

  The base isolation structure according to claim 5 is the base isolation base structure according to any one of claims 1 to 4, wherein the lower frame and the upper frame are made of fiber reinforced concrete. It is.

  The present invention makes it possible to easily manufacture a frame of any shape without any bar arrangement work, especially by forming the lower frame and the upper frame from fiber reinforced concrete. Product accuracy can be significantly improved. In this case, steel fibers or carbon fibers can be used as the reinforcing fibers.

  In the present invention, the lower frame and the upper frame for installing the seismic isolation device are all made of precast concrete, so the formwork and rebar construction necessary to install these frames are omitted. As a result, it is possible to greatly reduce labor and efficiency in on-site construction.

  1 and 2 show an example of the present invention. In the figure, a foundation slab 1 having an RC structure is constructed on the ground at the bottom of the root, and a plurality of seismic isolation devices 2 are provided on the foundation slab 1. The floor slab 3 of a detached house is constructed by RC structure.

  The foundation slab 1 is constructed of cast-in-place concrete by laying cracked stone 1a on the ground at the bottom of the root, placing a reinforcing bar 1b on the ground, and placing concrete 1c.

  The base slab 1 is provided with a lower gantry 4 at predetermined intervals in the carry direction and the span direction, and a seismic isolation device 2 is installed on each gantry 4.

The lower gantry 4 is formed in a block shape having a planar quadrilateral shape from precast concrete, and is formed so that the lower end portion has a quadrangular pyramid shape and gradually becomes a small diameter in the lower end direction.
In addition, horizontal adjustment bolts 4 a for horizontally installing the lower frame 4 are vertically provided at each corner portion of the lower frame 4. In this case, the horizontal adjustment bolt 4a is screwed into a nut (not shown) vertically embedded in the concrete of the lower gantry 4, and can be freely adjusted in the downward projection length by turning. It is a thing.

  The gantry 4 formed in this way is installed on the discarded concrete 1d placed on the split stone 1a, and is horizontally adjusted so that the upper end surface is horizontal by the horizontal adjustment bolt 4a of each corner. After that, a part of the upper part is left and most of the lower part is embedded in the concrete 1c of the foundation slab 1.

  The seismic isolation device 2 is a laminated rubber and a damping device, and is installed on the gantry 4 at positions determined by the necessary number and the structural design. In addition, if the seismic isolation apparatus 2 in this case is provided with these functions, a shape etc. will not be specifically limited.

  Further, the upper frame 5 is installed on each seismic isolation device 2, and among them, the receiving members 6 and 6 are continuously spanned between the upper frames 5 and 5 adjacent in the span direction. The receiving member 6 is formed from angle steel, and is fixed to both sides of the upper mounts 5 and 5 by bolting or the like.

  Further, the deck plate 7 is bridged between the receiving members 6 and 6 of the upper bases 5 and 5 adjacent to each other in the carry direction, and the end of each deck plate 7 is fixed on the receiving member 6.

  And the slab reinforcement 8a is arranged on the deck plate 7, and concrete 8b is laid, and the upper part of each upper frame 5 is embed | buried in the concrete 8b. In this way, the floor slab 3 of a detached house is constructed.

Next, the construction method of this invention is demonstrated based on FIGS.
1. First, the foundation slab 1 is constructed. At the time of construction, first, the cracked stone 1a is spread on the ground that has been cut. Then, the discarded concrete 1d is placed at a position where the seismic isolation device 2 is installed, and after the discarded concrete 1d is cured, positioning marking is performed thereon, and the lower frame 4 is installed. Then, the horizontal adjustment of the lower frame is performed by the horizontal adjustment bolt 4a of each corner so that the upper end surface is horizontal.
Further, the foundation reinforcing bar 1b is arranged on the split stone 1a, and the concrete 1c is placed to complete the construction of the foundation slab 1.

2. Next, the seismic isolation device 2 is installed on each lower frame 4, and the upper frame 5 is installed thereon. Then, the lower frame 4 and the upper frame 5 are fixed by the temporary fixing member 9 so that the seismic isolation device 2 does not operate during the subsequent work.
In this case, as the temporary fixing member 9, for example, a plate steel material can be used, and the temporary fixing member 9 can be easily removed by bolting the side portions of the lower frame 4 and the upper frame 5. Secure to.

3. Next, the receiving members 6 and 6 are horizontally bridged between the upper frames 5 and 5 adjacent to each other in the span direction, and the receiving members 6 and 6 are fixed to each side of the upper frame 5 by bolting or the like. .

4). Next, the deck plate 7 is bridged as a floor frame between the receiving members 6 and 6 of the upper bases 5 and 5 adjacent to each other in the crossing direction, and both end portions of each deck plate 7 are fixed on the receiving member 6. Then, the slab reinforcing bars 8a are arranged on the deck plate 7, and the concrete 8b is placed to complete the construction of the floor slab 3.
When a plywood is used as a floor frame instead of a deck braid, for example, as shown in FIG. 5, a plywood 10 bridged between receiving members 6 and 6 is supported from below by a support 11, and a plywood 10 and the support work 11 are removed after the construction of the floor slab 3 is completed.

  The present invention can perform seismic isolation of relatively light buildings, mainly single-family houses, very efficiently and economically.

An example of the seismic isolation base structure of this invention is shown, (a) is the top view, (b) is a front view. An example of the seismic isolation base structure of the present invention is shown, (a) is an enlarged sectional view taken along line II in FIG. 1 (a), (b) is a perspective view showing the positional relationship between the lower frame, the seismic isolation device and the upper frame. It is. (A), (b), (c), (d) is sectional drawing which shows a construction procedure. (A), (b), (c) is sectional drawing which shows a construction procedure. It is sectional drawing which shows the construction procedure at the time of using a plywood for a floor formwork. It is a front view of the foundation part which shows an example of the conventional seismic isolation base structure.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Foundation slab 1a Cracking stone 1b Foundation reinforcement 1c Concrete 1d Discrete concrete 2 Seismic isolation device 3 Floor slab 4 Lower frame 5 Upper frame 6 Receiving member 7 Deck plate 8a Slab reinforcement 8b Concrete 9 Temporary fixing member 10 Plywood 11 Support

Claims (5)

  In the base isolation slab comprising a foundation slab provided on the ground side, a floor slab provided on the building side, and a plurality of seismic isolation devices provided between the foundation slab and the floor slab, the foundation slab and floor A lower frame and an upper frame made of precast concrete are respectively provided on the slab at predetermined intervals in the direction of the building and in the span direction, the lower frame is in the foundation slab, and the upper frame is in the floor slab, respectively. A base-isolated base structure characterized in that a part of the base is provided and the base isolation device is provided between the lower base and the upper base.   The floor slab of a building is formed by laying a plurality of deck plates between receiving members spanned between a plurality of upper frames and placing concrete on the deck plates. Item 1. Seismic isolation base structure.   The lower end of the lower pedestal is formed so as to gradually decrease in diameter in the lower end direction, and a plurality of horizontal adjustment bolts are provided at predetermined intervals in the circumferential direction. Base isolation structure.   The base isolation structure according to any one of claims 1 to 3, wherein a temporary fixing member fixed to the lower frame and the upper frame is detachably fixed between the lower frame and the upper frame.   The seismic isolation foundation structure according to any one of claims 1 to 4, wherein the lower frame and the upper frame are formed of fiber reinforced concrete.

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