JP2007197916A - Base-isolated structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a base-isolated building, which dispenses with a double foundation as the demerit of the base-isolated building, and a clearance in the outer peripheral section of the building. <P>SOLUTION: A first layer floor surface (foundation-side structure) of the building is constructed in such a manner as to be integrated with ground. A sliding plate of a sliding bearing is arranged upward on the top surface of the first layer floor surface, and the sliding bearing with a rotary mechanism is arranged in the column base part of an upper structure directly above the sliding plate. An upside floor surface for connecting the respective column base parts together is constructed; many rolling bearings or sliding bearings are interposed between the upside floor surface and the foundation-side structure; and the self-weight of the upside floor surface and a live load on it are borne by the foundation-side structure. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention provides a seismic isolation device (including various laminated rubbers, sliding bearings, rolling bearings, etc.) between the ground and the structure to protect the structure from strong earthquake motion during a large earthquake. It relates to structures.

  The seismic isolation structure can reduce the vibration of the structure itself against strong earthquake motion during a large earthquake, so it not only increases the seismic safety of the structural framework of the building, but also prevents the fall of contained items such as internal furniture and equipment. The risk of falling / collision is reduced, and the seismic safety of the entire building can be dramatically improved.

  The seismic isolation structure is composed of a seismic isolation layer in which a base rubber or base structure and an upper structure are provided with seismic isolation devices such as laminated rubber. The horizontal stiffness of the seismic isolation layer is determined by the horizontal stiffness of each layer of the upper structure. Is also set to be significantly lower.

  When seismic motion acts on the seismic isolation structure, horizontal deformation concentrates on the seismic isolation layer, and each layer of the upper structure vibrates slowly. Since the seismic isolation layer resistance is set low, seismic force greater than that of the seismic isolation layer is not transmitted to the superstructure, resulting in a reduced response acceleration of the structure and the building being housed inside. Both things can be safely protected.

The idea of seismic isolation structures has already been proposed for more than 100 years, but in 1985, actual seismic isolation buildings began to be built in Japan. As proposals of relatively new recent seismic isolation structure buildings, for example, there are those shown in Patent Documents 1 to 3.
As shown in these patent documents and FIG. 6 (1), the conventional seismic isolation structure building first forms a foundation on a pile or the ground, and places the seismic isolation device 3 thereon, and the device. The upper building is supported by the structure, adopting the double foundation method, and providing the clearance 6 between the foundation on the ground side and the upper building to separate the building from the ground (hereinafter referred to as “base seismic isolation”) (See Patent Documents 1 to 3).

As another method of constructing the seismic isolation layer, as shown in FIGS. 6 (2) and 7 (1), the seismic isolation device 3 is arranged on the column head of the column 15 on the basement floor or the ground floor (hereinafter referred to as the “capital”). A method of sandwiching a base isolation layer between an underground floor and a ground floor as shown in FIG. 7 (2) has been put into practical use.
In some cases, a base isolation layer is placed in the middle of the ground floor, or a base isolation device is placed between the pillars on the ground floor. ing.
JP-A-10-002126 JP 11-152928 A JP 2000-297559 A

Despite being able to provide excellent safety performance against large earthquakes, the use of seismic isolation structures is limited to only a part of them. This is because. The main disadvantages are the following two points.
(1) The construction cost is higher than that of conventional seismic structures.
(2) There are difficulties in architectural planning.

The main factors that increase the cost of the base-isolated structure (1) are the following points.
B) The manufacturing cost of the seismic isolation device is high.
B) In order to construct a seismic isolation layer, the base isolation requires a double foundation, and the structure frame must be increased by one layer.
C) Although double foundations can be omitted in stigma-based isolation, a fireproof coating that can tolerate large horizontal deformation of the seismic isolation device is required.
D) In order to ensure horizontal movement as a seismic isolation structure, it is necessary to provide clearance around the building. For this reason, the retaining wall, the expansion joints around the building and the connecting part, flexible piping joints, etc. must be expensive.

The difficulty in the architectural plan of paragraph 0007 (2) above is mainly related to the above (1) d). In other words, since a clearance is required between the entire circumference of the building and the surrounding ground, an expansion joint that allows a relative displacement of ± several tens of centimeters generated in the event of an earthquake on the flow line passing through the clearance part in two horizontal directions. Is that you need.
In particular, in recent years, the access part to buildings often requires barrier-free, and in order to realize a flow line connection part without a vertical step, a complicated fitting hardware is provided, which increases the cost. It is also.

  In addition, if the seismic isolation structure has an underground floor, the seismic isolation device is placed on the foundation (under the basement floor), so that it can stand on the outside of the basement outer wall around the building to ensure clearance around the building. It is necessary to provide a mold retaining wall, and the retaining wall becomes extremely thick due to earth pressure, which increases the cost.

  Therefore, the present invention realizes the “basic seismic isolation that does not require the seismic isolation clearance around the building”, which has been considered essential for seismically isolated buildings, and is necessary for the conventional base isolation. This eliminates the need for retaining walls and expansion joints.

The present invention adopts the following configuration in order to solve the above points.
<Configuration 1>
A foundation-side structure constructed in contact with the ground; an upper structure of one or more layers arranged on the foundation-side structure and composed of columns and beams; and the upper portion of the foundation-side structure The sliding plate of the sliding support that is positioned so that the sliding surface is facing upward and at the same level as the surrounding floor surface at and around the position where the pillar of the structure rides, and the upper part that is located directly above the sliding plate The slider of the sliding bearing that is placed downward facing the sliding surface of the sliding plate at the bottom of the structure column, and some of the sliding supports that are not arranged at the bottom of the column of the upper structure A base-isolated structure comprising a restoration device arranged on a column and restoring a horizontal displacement.

The “foundation-side structure” in Configuration 1 includes a foundation structure that is integrated in contact with the ground below or near the ground surface, or a lower structure that is integrally constructed on top of the foundation structure. Further, the “upper structure” includes one or more building structures composed of pillars, beams, etc. on the foundation side structure.
In seismic isolation structures, the first requirement is not to transmit ground motion directly to the structure. Therefore, until now, as shown in FIG. 6 (1), the basic configuration has been to create a large pool-like depression in the ground, place a seismic isolation device here, and place a structure on it. As the seismic isolation device, various well-known laminated rubbers, sliding bearings, rolling bearings and the like are used.
In addition to seismic isolation devices, the bottom and surroundings of the structure are completely separated from the ground, and even if relative displacement occurs between the ground and the structure during an earthquake, it does not touch the ground side. Ensuring sufficient clearance has been an important requirement = an absolute condition.

  Since the present invention is also intended for a seismic isolation structure, there is no difference in seismic input isolation, but the space previously provided for input isolation = “seismic isolation layer” may not be created. It is the biggest feature.

  That is, the foundation and the lowermost floor surface (foundation side structure) are constructed integrally with the ground in the same manner as the conventional earthquake-resistant structure. A slip surface is formed on the upper surface of the foundation-side structure, and a seismic isolation device (slide support slider) is arranged at the lowest part (= column base) of the upper structure column immediately above.

  By placing sliding bearings on the column base of the upper structure, the second and higher layers can be seismically isolated, and the first layer (the bottom floor) is integrated with the ground. There is no need to build a seismic isolation clearance during the period. With this basic configuration, it is possible to realize a base isolation structure without building a base isolation layer as a space between the ground and the structure.

  The sliding surface on the upper surface of the foundation side structure is configured at the same level as the surrounding floor slab surface. Due to this condition, even if there is an excessive earthquake input exceeding the design assumption, the fail-safe function that maintains the safety of the entire base isolation structure without the upper building falling off the base isolation device. It is a seismically isolated structure.

<Configuration 2>
A foundation-side structure constructed in contact with the ground; an upper structure of one or more layers arranged on the foundation-side structure and composed of columns and beams; and the upper portion of the foundation-side structure The sliding plate of the sliding support that is positioned so that the sliding surface is facing upward and at the same level as the surrounding floor surface at and around the position where the pillar of the structure rides, and the upper part that is located directly above the sliding plate A slider of a sliding support disposed at the lowermost part of the pillar of the structure and facing downwards on the sliding surface of the sliding plate, the support member fixed to the base side structure or the base side structure, and the upper structure A seismic isolation structure, comprising: a restoring device that restores a horizontal displacement, disposed between the body and a connecting member fixed to the upper structure.

  The “support member” in the configuration 2 is, for example, the support column 15 shown in FIG. 2 (2) or the support column 71 shown in FIG. 5 (2). Further, the “connecting member” is, for example, the joining footing 43 shown in FIG. 2 (2) or the connecting portion 73 shown in FIG. 5 (2).

<Configuration 3>
In the seismic isolation structure according to Configuration 1 or 2, the sliding bearing employs a sliding bearing with a rotation mechanism or an elastic sliding bearing, and the restoring device employs a laminated rubber-based seismic isolation device. Seismic isolation structure.

  Configuration 3 shows the most common seismic isolation device configuration of the present invention, and a sliding bearing with a rotation mechanism or an elastic sliding bearing is adopted as the sliding bearing arranged on the column base.

Since the column to which the sliding bearing is attached is a cantilever system downward from the second layer, a rotation angle due to a horizontal force is generated at the column base corresponding to the tip of the column.
Therefore, it is necessary for the slide bearings arranged on this column base to be able to absorb the rotation angle of this column, and for this purpose, a slide bearing with a rotation mechanism or an elastic bearing that can absorb rotation is connected in series. It is necessary to adopt a sliding bearing.

  As a device that bears the restoring force of the seismically isolated building of the second and higher layers, laminated rubber bearings (natural rubber laminated rubber, laminated rubber with lead plug, laminated rubber with tin plug, high damping laminated, etc.) are adopted. be able to.

<Configuration 4>
The seismic isolation structure according to any one of Configurations 1 to 3, wherein a floor surface that connects the column base portions of the upper structure is provided, and the floor surface is pinned to the floor plate alone or to the floor plate and the column. A seismic isolation structure, characterized in that a sliding bearing or a rolling bearing is disposed between the floor plate or floor beam and the foundation side structure.

  In configurations 1 and 2, since the floor surface of the first layer is integrated with the ground, the objects placed on the floor of the first layer receive the benefits (response acceleration reduction effect) of the seismic isolation structure. I can't.

In order to solve this problem, the column bases at the top of the seismic isolation device may be connected by a beam, and the floor surface may be constructed on the foundation side structure so as not to contact the foundation side structure.
However, providing a rigidly-connected beam that connects the column bases directly above the seismic isolation device results in the construction of a seismic isolation layer having two floor surfaces above and below the seismic isolation device. The construction procedure must also be the foundation structure → seismic isolation device installation → upper structure first layer beam / floor construction, and it will have the same configuration as the conventional seismic isolation structure, which will kill the merit of the present invention. become.

  The features and merits of the present invention are that a frame that bears the seismic force at a position directly above the seismic isolation device, that is, a beam rigidly joined to the column is unnecessary. In order to make use of this merit and to generate a seismic isolation effect on the first floor, the configuration 3 solves this problem with a completely new idea. That is, another floor surface (hereinafter referred to as “upper floor surface”) is formed on the upper surface of the foundation-side structure, and the “self-weight of the upper floor surface and the load on the upper portion thereof are supported by the foundation-side structure. "

  However, if the upper floor is simply placed on the foundation structure, a large frictional force is generated, which may kill the seismic isolation effect of the entire building, so rolling support or sliding between the foundation side structure and the upper floor is possible. The horizontal frictional force on the upper floor is reduced through the support.

  And the upper floor surface is connected with the column base part on the slide support arrange | positioned at the column base part. When a beam for supporting the upper floor surface is provided, the beam end is pin-joined to the column base, or is supported on the foundation side structure by a sliding bearing or a rolling bearing.

  With the above configuration, it is possible to enjoy the benefits of the seismic isolation structure from the floor surface of the first layer, and by adjusting the frictional force of the upper floor surface of the first layer, the horizontal resistance force of the entire base isolation layer In addition, the energy absorption performance (attenuation performance) can be adjusted.

  Moreover, since the weight of the upper floor surface is supported by the foundation side structure, the thickness of the upper floor surface can be made extremely small and a thin floor can be formed, and there is almost no loss in floor height while constituting a double floor. Absent. As will be described later, this effect is particularly advantageous when renovating an existing building with a base isolation structure (base isolation retrofit).

<Configuration 5>
In the seismic isolation structure according to any one of Configurations 1 to 4, the foundation-side structure employs a combined foundation structure of a pile and a floating foundation (hereinafter referred to as “pile raft foundation structure”). Seismic isolation structure.

The greatest feature of the present invention is that the first layer (= foundation side structure) can be constructed integrally with the ground. Therefore, when the ground is soft, it is a natural choice to support the pillar directly below the pile foundation, but the vertical load of the first layer (the weight of the foundation side structure and the first layer upper floor and the load) It is reasonable to support it directly on the ground directly below it, and it is reasonable to adopt the “pile raft foundation structure” that is the combined foundation structure of friction pile and floating foundation as the most suitable foundation structure method .
Moreover, since the support weight of a seismic isolation apparatus and a pile is reduced by making 1st layer weight support on the ground, it becomes possible to design both more economically.

<Configuration 6>
In the seismic isolation structure according to any one of configurations 1 to 5, any one of a pile head pin joint, a pile head rotary spring joint, or a pile head semi-rigid joint is employed for a pile head that supports the foundation side structure. Seismic isolation structure characterized by

When the ground is soft and the part directly below the column is supported by a pile foundation, the pile also tilts due to the horizontal shear deformation of the stratum during an earthquake. When the pile head is rigidly connected by the underground beam of the foundation side structure, a large pile head moment is generated in the pile head and the underground beam, so only a large member cross section is required for both the pile and the underground beam. However, this rotates the joint between the pile head and the underground beam, and the sliding plate of the sliding support arranged just above it also tilts. When the slip plate is inclined, the restoring force characteristic of the slip performance is affected, and the slip resistance force varies depending on the direction.
In order to reduce the impact on the sliding performance, it is most preferable to completely pin-join the pile head to the upper foundation side structure. It is necessary to reduce the degree of fixation of the head joint as much as possible.
Pile head joining devices (for example, a device called BP-CAP) for completely pin-joining the pile heads have already been developed and put to practical use.

<Configuration 7>
The base-side structure of the seismic isolation structure according to any one of Configurations 1 to 6 in the existing seismic structure in which the foundation or underground structure is constructed in contact with the ground Consider the body, cut the column base of the first floor pillar and attach the slider of the sliding support, place the sliding plate on the first floor slab below it, the middle part of the pillar without the sliding support, Alternatively, by disposing the restoring device that restores a horizontal displacement between a supporting member fixed to the foundation-side structure and a connecting member fixed to the upper structure, A base-isolated structure that has been modified and changed to the same building structure as the base-isolated structure.

  The configuration of the present invention can also be applied to existing structures. In order to make an existing seismic structure seismic isolation structure, conventionally, it was necessary to dig under the foundation and install a seismic isolation device while underpinning to support the structure in the ground. If the seismic isolation structure of the present invention is applied, the seismic isolation device can be placed on the ground floor and on the first floor column base where the construction is most easily performed, so that the seismic isolation work can be performed much more easily.

  Hereinafter, the present invention will be described with reference to the drawings illustrating embodiments.

FIG. 1 illustrates the basic configuration 1 of the present invention. FIG. 1 (1) is a cross-sectional configuration of the entire seismic isolation structure of the present invention, and FIG. 1 (2) is FIG. 1 (1). The cross-sectional detail figure of the attachment part vicinity of the sliding type seismic isolation device 2 with a rotation mechanism arrange | positioned at the column base part which attached | subjected (circle) is shown.
The base-isolated structure of Example 1 is arranged on a foundation side structure beam (underground beam) 13 and a floor slab 14 constructed in contact with the ground 1, and arranged on the foundation side structure. The upper surface 4 of one or more layers composed of beams and the position of the base structure on which the pillars of the upper structure ride and the periphery of the upper structure 4 are on the same level as the surrounding floor surface. The sliding plate 23 of the sliding bearing arranged in the above manner, and the rotating mechanism arranged downward facing the sliding surface of the sliding plate at the lowermost part of the column of the upper structure located immediately above the sliding plate A slider 21 of a sliding type seismic isolation device (sliding bearing) 2, and a restoring device 3 which is arranged on a part of the pillars where the sliding bearing is not arranged at the bottom of the upper structure pillar and restores a horizontal displacement; It has.

  As shown in FIG. 1 (1), in the present invention, the foundation side structure can be integrated with the ground 1 in the same manner as a conventional earthquake-resistant structure building, so that a double foundation is not required even though it is a basic seismic isolation structure. A simple and clear building structure is realized.

  FIG. 1 (2) is an enlarged cross-sectional view of the vicinity of the column base portion where the sliding type seismic isolation device 2 with a rotating mechanism of the present invention is disposed. The sliding plate 23 is at the same level as the upper surface of the surrounding floor surface 14. Therefore, even if the seismic motion exceeding the design assumption acts and the sliding displacement of the seismic isolation device becomes large, no abnormality will occur in the building, ensuring the safety of the building. ing. That is, the present invention is a seismic isolation structure having a fail-safe function.

As shown in FIG. 1A, the upper column 41 of the seismic isolation device is a cantilever column protruding downward from the second floor. Therefore, although the horizontal seismic force (column shearing force) acting on this column is reduced by the function of the seismic isolation device, the column base is inclined because the horizontal force causes horizontal deformation of the column. .
If the sliding member 22 of the sliding support is directly connected to the bottom surface of the column, an inclination angle is generated between the sliding member 22 of the slider and the sliding plate 23 fixed to the floor due to the inclination of the column, and thus normal sliding movement cannot be performed. . In order to avoid this, as shown in FIG. 1 (2), either the slider 21 of the sliding bearing is provided with a rotating mechanism (an inclination absorbing mechanism of the column base) or an elastic sliding bearing capable of performing its function. It is necessary to do it.

  Fig. 1 (2) also shows a method of joining the pile heads on the lower side of the seismic isolation device. Since the ground itself undergoes horizontal shear deformation during an earthquake, the pile 10 is subjected to forced deformation by the ground 1 and the pile head is inclined. At this time, if the pile head is rigidly connected to the underground beam, a large bending moment is generated at the pile head, and this bending moment is transmitted to the underground beam. This is necessary, and the sliding plate 23 itself disposed on the top of the pile is inclined. When the slip plate 23 is inclined, the slip performance is less preferable in the downhill direction, and the resistance force is increased in the uphill direction, and the direction of the slip performance is generated, which is not preferable as a seismic isolation structure.

  Therefore, in the present invention, the pile head 11 directly below the sliding plate is completely pin-joined, or adopts elastic rotary spring joining or semi-rigid joining, and the joining rigidity between the pile head and the underground beam, that is, pile head fixing. Adopt a joining method that makes the degree as small as possible. This is configuration 6 of the present invention. If the pile head complete pin joint is adopted, even if horizontal displacement occurs in the ground, the sliding plate 23 is maintained horizontal without being affected by the inclination of the pile head, and normal sliding performance can be exhibited. It becomes.

FIG. 2 shows an embodiment showing the arrangement method of the sliding support and the restoring device in the present invention. FIG. 2 (1) shows a case where the sliding support 2 is arranged at the column base of the pillar in the building and the laminated rubber bearing 3 as a restoring device is arranged near the center of the building outer peripheral pillar. Since the horizontal force of the sliding support 2 is small, the bending moment of the column head does not become so large even if it is arranged on the column base, and the design is not difficult.
On the other hand, since the horizontal force borne by the laminated rubber 3 as the restoring material may be large, it is most important for both the upper structure and the foundation side structure to be arranged near the center of the column height. It is efficient and the column cross section can be designed small.

2 (2) shows a method in which the sliding support 2 is arranged on the column bases of all the columns of the first layer of the building, and the restoring device 3 is arranged directly below the second floor without supporting the building weight. Show.
That is, the restoring device 3 that restores the displacement in the horizontal direction is provided between the support column 15 fixed to the base side structure and the joining footing 43 fixed to the upper structure. A support column 15 that supports the laminated rubber bearing 3 as a restoring device is raised from the base-side structure, and a bonding footing 43 is provided and bonded to the upper structure just below the floor beam on the second floor. The planar position of the support column 15 may be inside the building or outside the building, but it is preferable that the support column 15 be arranged on the outer periphery of the building as much as possible in order to increase the torsion resistance of the entire building.

  FIG. 3 is a sectional view showing Example 4 of Configuration 4. In FIG. 4A, a beam 52 connecting the column bases is arranged, and an upper floor 51 is provided thereon. Since the laminated rubber 3 for the restoring device is also arranged at the column base, the beam end portion of that portion is bent upward so as not to interfere with the deformation of the laminated rubber. In this invention, since the edge part of this beam needs to be pin-joined to a pillar, it is convenient to install after attaching a seismic isolation apparatus. After the installation of the beam, the floor will be built, but part of it will be partially removable so that the seismic isolation device can be easily inspected and confirmed.

  FIG. 3 (2) shows a case where the laminated rubber bearing 3 as a restoring device is attached near the center height of the column. In this case, the lower column 15 of the restoring device is the foundation side structure. Therefore, it cannot be joined to the seismic isolation floor 5. Therefore, a sliding bearing or a rolling bearing is disposed at the end of the beam 52 so that the vertical load at the end of the beam is supported by the foundation side structure, and the horizontal relative between the pillar 15 below the laminated rubber and the base isolation floor 5 is A gap (clearance) is secured so that the displacement is possible.

  FIG. 4 is a diagram illustrating Example 5 of Configuration 4. In FIG. FIG. 4 (1) shows a cross-sectional view of the entire configuration, in which a floor surface 5 is provided for connecting the first-stage column bases of the columns 41, but a beam for supporting it is not provided. 4 (2) and 4 (3) are enlarged cross-sectional views of the circled portion of the floor surface 5 in FIG. 4 (1).

  In FIG. 4B, by arranging a large number of ball bearings 53 (rolling elements) under the floor surface 51, the horizontal resistance force can be increased while supporting the vertical load on the floor surface by the foundation-side structure. It is a way to eliminate. The rolling friction coefficient μ due to the ball bearing is about μ = 0.01 to 0.001, and it can be considered that the horizontal resistance can be almost ignored. In order to hold the positions of the rolling elements 53 at regular intervals, the rolling elements are accommodated in a position holding device holder 54.

  FIG. 4 (3) is a method of supporting the floor surface with a large number of sliding supports, in which the sliding material 56 is fixed to the floor slab 14 on the foundation side structure side, and the lower surface of the upper floor is used as a sliding plate. is there. For the bottom surface 55 of the upper floor, it is appropriate to use a stainless steel plate or the like as having both the performance as a slip surface having high rust prevention performance and the performance of the support mold of the upper floor. By performing appropriate floor finishing on this stainless steel plate, the first layer floor surface 51 suitable for the application can be configured. By combining the sliding material 56 and the sliding plate 55, the sliding friction coefficient can be set in a range of about μ = 0.01 to 0.15, and the resistance and damping performance (energy absorption performance) of the seismic isolation layer as a whole are preferable. Can be adjusted to the value.

  FIG. 5 is an example of configuration 7 when the seismic isolation structure of the present invention is applied to an existing building. Fig. 5 (1) shows a laminated rubber bearing as a restoration device by cutting the column base of the middle pillar of the first floor of the existing building, placing the sliding support 2 here, and cutting the vicinity of the center of the outer pillar of the building. 3 is arranged. After that, the seismic isolation floor surface 51 connecting the first floor column bases is constructed, and a clearance for horizontal displacement is secured around the support column 15 of the restoring device 3.

  In FIG. 5 (2), the sliding bearings 2 are arranged on the column bases of all the columns on the first floor of the existing building, and the laminated rubber bearing 3 as a restoring device is newly installed in the vicinity of the outer periphery of the building. This is a case where upper connecting portions 72 to 73 are additionally attached. In this method, there is an advantage that the seismic isolation floor 51 connecting the first floor column bases can be constructed over the entire plane. In this method, since the restoring device does not support the vertical load, it is possible to adopt a laminated rubber with the optimal horizontal rigidity according to the building weight, and not only can the seismic isolation cycle be set freely, but also the restoration. Since the device is arranged outside the building, the effect of suppressing the torsional vibration of the entire building is further enhanced.

  The conventional method of seismic retrofitting existing seismic structures to seismic isolation structures involves excavating the foundations of existing buildings and inserting seismic isolation devices near the foundation and pile heads in a narrow underground space under the building floor. It was necessary to perform difficult and time-consuming work. In the methods of Examples 6 and 7 of the present invention, the seismic isolation work for the existing building can be performed directly on the floor of the first floor above the ground, which is the easiest to carry out. It becomes easy and efficient, and construction costs are much more economical.

  Seismic isolation structures have been built in Japan since 1985 and have already been in use for 20 years, but as of the end of 2005, the total number of buildings was only about 1500. As described in paragraphs 0007 and 8, the main causes are (1) the initial construction cost is higher than that of the conventional earthquake-resistant structure, and (2) the difficulty in building planning.

The present invention makes it possible to insulate from the ground without providing a double foundation of the conventional method, which was the cause of the cost increase, and the expansion joint portion around the building which is the greatest factor in the difficulty in seismic isolation building planning Is unnecessary.
According to the present invention, the structure of the base-isolated building is simply and clearly improved, the design becomes much easier, and at the same time, the cost increase problem is greatly improved. Further, the present invention can remarkably easily perform seismic isolation structure repair work for existing structures.
The present invention can be expected to promote the spread of seismic isolation structures with high safety performance, including both new construction and renovation of existing buildings.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the basic composition of the seismic isolation structure of Example 1 of this invention, (1) Sectional drawing which shows the structure of the whole seismic isolation building, (2) It arrange | positions at the column base part of (circle) part of the figure It is an expanded sectional view around a sliding bearing. It is a figure which shows each seismic isolation structure of Example 2 and Example 3, (1) Sectional drawing which shows a seismic isolation structure when the laminated rubber support as a restoring device is arrange | positioned in the height center vicinity. (2) It is sectional drawing which shows a seismic isolation structure when a slide support is arrange | positioned at all the column base parts, and the decompression | restoration apparatus is attached without supporting the building weight. It is a figure which shows the seismic isolation structure of Example 4. (1) The beam which connects a column base part is provided, the floor surface of the 1st layer is comprised on it, and a decompression | restoration apparatus is also a column base position Sectional view showing the seismic isolation structure when it is placed in (2) Similar to (1), but the seismic isolation structure when the restoration device is placed near the center of the column height It is sectional drawing shown. It is a figure which shows the seismic isolation structure of Example 5. (1) Although the floor surface which connects the column base part of the 1st layer is comprised, the beam which supports it is not provided, but the floor vertical load is lowered. Sectional view showing the entire building when supported by the foundation side structure on the side. (2) When a large number of rolling elements (ball bearings) are arranged between the upper floor surface and the lower foundation side structure. Fig. 3 is an enlarged cross-sectional view showing the floor surface of the same figure. (3) The floor surface of the same figure when the bottom surface of the upper floor surface is a sliding plate surface and a number of sliding materials fixed to the foundation side structure are arranged below it. FIG. It is the figure which shows the execution example where the present invention is applied to the existing seismic structure building and the seismic isolation structure is renovated. (1) Sliding bearing at the middle column base and the laminated rubber bearing for restoration near the center of the outer column Cross-sectional view showing the seismic isolation structure when installing the door. (2) Sliding bearings are attached to the column bases of all existing columns, and the restoration device does not support the building weight and provides new mounting columns and mounting members. It is sectional drawing which shows a seismic isolation structure in the case of attaching. It is a figure showing the composition of a conventional seismic isolation structure, (1) A cross-sectional view showing the basic composition of a basic seismic isolation structure that configures a double foundation and places a seismic isolation device, (2) It is sectional drawing which shows the example of the middle floor seismic isolation which arrange | positions a seismic isolation apparatus. It is a figure showing composition of the conventional seismic isolation structure, (1) Sectional drawing which shows the example of the middle floor seismic isolation which arranges a seismic isolation device in the head of the first floor, (2) Between the basement and the first floor It is sectional drawing which shows the example of the middle floor seismic isolation which provides a base isolation layer.

Explanation of symbols

1: Ground 10: Pile 11: Pile head joint (pile head joint device)
12: Pile head foundation footing 13: Beam of foundation side structure (underground beam)
14: Floor slab of foundation-side structure 15: Support column for base-side structure base isolation device 2: Sliding seismic isolation device with rotating mechanism 21: Slider 22: Sliding material 23: Sliding plate 3: Base isolation for restoration Equipment (laminated rubber bearing)
4: Upper structure 41: Upper structure column 42: Beam of upper structure 43: Footing for seismic isolation device of upper structure 5: Retrofitted floor just above seismic isolation device 51: Upper floor surface 52: Upper floor surface Supporting beam 53: Rolling element for upper floor (ball bearing)
54: Position holder for the above-mentioned 55: Sliding plate at the bottom of the upper floor 56: Sliding material for supporting the upper floor 6: Horizontal deformation clearance for seismic isolation 7: Existing building for seismic retrofit 71: Seismic isolation mounting column 72 for seismic recovery : Seismic isolation device mounting beam for seismic recovery 73: Seismic isolation device mounting footing for seismic recovery 74: Seismic isolation device base beam for seismic recovery 8: Existing structure

Claims (7)

A foundation-side structure constructed in contact with the ground;
One or more upper structures that are arranged on the foundation-side structure and are composed of columns and beams;
A sliding plate of a sliding support disposed at a position where the pillar of the upper structure rides on and around the base side structure, with a sliding surface facing upward and at the same level as the surrounding floor surface;
A slider of a sliding support disposed at the lowest part of the column of the upper structure located directly above the sliding plate, and facing downward to the sliding surface of the sliding plate;
A seismic isolation structure, comprising: a restoring device that restores a horizontal displacement by being arranged on a part of a column that is not provided with a sliding support at the lowest part of the column of the upper structure. A foundation-side structure constructed in contact with the ground;
One or more upper structures that are arranged on the foundation-side structure and are composed of columns and beams;
A sliding plate of a sliding support disposed at a position where the pillar of the upper structure rides on and around the base side structure, with a sliding surface facing upward and at the same level as the surrounding floor surface;
A slider of a sliding support disposed at the lowest part of the column of the upper structure located directly above the sliding plate, and facing downward to the sliding surface of the sliding plate;
A restoring device for restoring a horizontal displacement, disposed between the base-side structure or a support member fixed to the base-side structure and a connecting member fixed to the upper structure or the upper structure; A seismic isolation structure characterized by the provision. In the seismic isolation structure according to claim 1 or claim 2,
The sliding bearing adopts a sliding bearing with a rotation mechanism or an elastic sliding bearing,
A seismic isolation structure using a laminated rubber-based seismic isolation device as the restoration device. In the seismic isolation structure according to any one of claims 1 to 3,
A floor surface for connecting the column base portions of the upper structure is provided;
The floor is composed of a floor plate alone, or a floor beam pinned to the floor plate and a pillar,
A seismic isolation structure, wherein a sliding bearing or a rolling bearing is disposed between the floor plate or floor beam and the foundation side structure. In the seismic isolation structure according to any one of claims 1 to 4,
A base-isolated structure in which the foundation-side structure employs a combined foundation structure of a pile and a floating foundation (hereinafter referred to as “pile raft foundation structure”). In the seismic isolation structure according to any one of claims 1 to 5,
A seismic isolation structure, wherein a pile head pin joint, a pile head rotary spring joint, or a pile head semi-rigid joint is employed for a pile head that supports the foundation-side structure. The base of the seismic isolation structure according to any one of claims 1 to 6, wherein the base or the underground structure is constructed in contact with the ground, and the portion below the first-floor slab is on the ground. As a side structure,
Cut the column base of the 1st floor column and attach the slider of the slide support, and place the slide plate on the 1st floor slab below it,
The restoring device that restores a horizontal displacement is disposed between an intermediate portion of the column to which the sliding bearing is not attached, or a support member fixed to the foundation-side structure and a connecting member fixed to the upper structure. Therefore, the base-isolated structure has been modified and changed to the same building configuration as the base-isolated structure according to claim 1.

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