JP2013199766A - Mounting method for base isolation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mounting method for a base isolation device which reduces manufacturing cost of a combination body for mounting the base isolation device and makes construction work easy in mounting the base isolation device on a structure, such as an architectural structure.SOLUTION: One end of a box nut 30 having retaining bolt holes at both ends is welded to the surface of a base through-hole of a base plate 2. A combination body, in which an anchor plate 40 is bolted to a retaining bolt hole 30b at other end of the box nut, is prepared. The combination body is arranged at a predetermined position on a structure surface. Reinforcements are disposed into a clearance between the base plate 2 and the structure surface, and concrete or cement mortar is placed to form an installation structure body in which the combination body is buried, and then a base isolation device is placed on the base plate 2. A mounting bolt is screwed to a retaining bolt hole 30a on the base plate of the box nut 30 via a flange through-hole and the base through-hole to fix the base isolation device to the installation structure body.

Description

  The present invention relates to a method for attaching a seismic isolation device made of laminated rubber or the like between an upper structure and a lower structure in order to provide seismic isolation support for a structure such as a building.

  Seismic isolation devices, in particular laminated rubber type seismic isolation devices, generally have flange plates on the top and bottom of laminated rubber composed of alternately laminated rubber sheets and steel plates. It attaches between each structure via the base plate installed in each structure and lower structure. Depending on the type or structure of the seismic isolation device or the structure, there are various types of the flange plate and the corresponding base plate such as a square or a circle.

As a method for attaching such a seismic isolation device, a method as shown in FIGS. 1 to 3 (hereinafter referred to as “conventional construction method”) is generally used. That is, the flange plate 1 and the base plate 2 are respectively provided with a flange through hole 1a and a base through hole 2a corresponding to each other, and the blind through bolt holes 3a are formed at both ends on the structure side of the base through hole 2a of the base plate 2. One end of the cap nut 3 having 3b is welded in advance by the welding leg length 9. The other end of the cap nut 3 is screwed with an anchor bolt 6 made of a cutting bolt without a head, and a fixing plate 4 is attached to the anchor bolt 6 by being sandwiched between nuts 8a and 8b. At the time of mounting, the flange through-hole 1a and the base through-hole 2a are matched, and then the fixing bolt 5 is inserted, and the tip thereof is screwed into the blind bolt hole 3a, whereby the flange plate 1, base plate 2, cap nut 3 Are fastened together. The fixing plate 4 is for resisting stress acting to pull out the cap nut 3 from the installation structure X due to vibration such as an earthquake, and is fixed to a predetermined position on the anchor bolt 6 by nuts 8a and 8b.

At the time of mounting the seismic isolation device G, first, a combination body (hereinafter referred to as “combination body”) formed by attaching the members such as the cap nuts 3 to the base plate 2 at a predetermined distance from the installation surface of the structure. After the horizontal arrangement, a reinforcing bar (not shown) is disposed in the gap between the base plate 2 and the structure, and then concrete or mortar is driven to form an installation structure X in which the combination is embedded. After the installation structure X is formed, the seismic isolation device G is installed on the base plate 2, the flange plate 1 and the through holes 1 a and 2 a of the base plate 2 are aligned, and the fixing bolt 5 is passed through the cap nut 3. The seismic isolation device G is fixed to the base plate 2 by being screwed into the blind bolt hole 3a. This attachment method is the same in fixing the upper and lower flange plates 1 and the upper and lower base plates 2 of the seismic isolation device G. In the event of an earthquake, the installation structure X vibrates with the lower structure, but the seismic isolation device G alleviates the transmission of vibration to the upper structure.

Moreover, as shown in the installation method of the seismic isolation device described in Patent Document 1, the jig plate is removed after embedding a cap nut or the like in the installation structure using a temporary jig plate instead of the base plate, and the installation structure There has also been proposed a method in which only the blind bolt hole of the cap nut is opened on the body surface, and the flange plate is directly fixed to the cap nut with the mounting bolt.
Japanese Patent Laid-Open No. 11-50694

  In the installation work of the seismic isolation device, the distance from the base plate to the fixing plate, that is, the total length of the member to be embedded in the installation structure (hereinafter referred to as “embedding length”), depending on the scale and structure of the building, etc. Is written). In the conventional construction method, a combination body is manufactured by welding a cap nut to a base plate, screwing an anchor bolt to the cap nut, and attaching the fixing plate to the anchor bolt with upper and lower nuts at a work site or the like. And carry it to the construction site. At the construction site, the combined body is installed with a separate support member (not shown) in a predetermined position on the formwork that has been pre-arranged while maintaining a level level, and then the concrete or The installation structure is formed by driving mortar.

  Usually, about 8 to 12 fixing bolts are used to attach one seismic isolation device, so the same number of members such as cap nuts, anchor bolts, and fixing plates constituting the combined body are required. Cap nuts are generally manufactured by turning a steel bar having a diameter of about 4 cm to 9 cm with a lathe to form threaded bolt holes at both ends, but many conventional methods require it. In general, the cap nuts are custom-made each time according to the specifications required at the construction site. Here, if the total length of the cap nut is set as the required embedding length and the fixing plate is directly attached to the tip thereof, members such as anchor bolts and upper and lower nuts for fixing the fixing plate become unnecessary, and not only the number of parts can be reduced, Since the above-described positioning work is not necessary, the cost can be greatly reduced.

However, for example, a relatively large and expensive NC lathe capable of high precision control is required for the boring and threading of a relatively long steel bar having a total length of 30 cm or more with a blind bolt hole. Since it was difficult to process with the popular type of small lathes possessed by various workshops, the number of compatible workshops was limited, which caused the cost of the machining process to increase. Therefore, in the conventional construction method, a combination method of a cap nut and an anchor bolt having a total length of about 15 cm has been adopted.

However, in this method, a positioning operation for attaching the fixing plate to an accurate position for all anchor bolts occurs at a work place or the like. Since a large-scale structure requires a large number of seismic isolation devices, the amount and time required for such positioning work increase. In addition, during transportation of the completed assembly to the construction site, the upper and lower nuts may loosen due to vibrations and the position of the fixing plate may shift, so it may be necessary to readjust it at the construction site. .

The cost increase factors associated with the production of the cap nut and the positioning operation of the fixing plate as described above are unavoidable in the conventional method, and the same applies to the installation method of the seismic isolation device described in Patent Document 1. For this reason, the production and construction cost reduction of the combination for attaching the seismic isolation device has been an important issue in reducing the introduction cost of the seismic isolation device and, in turn, promoting its spread.

  The present invention has been made in view of the above-mentioned points. The technical feature of the present invention is that the cap nut is standardized to a short one that can be easily processed by a popular small lathe, and the fixing plate is fixed to the end of the cap nut. When it is directly attached to the part and an embedded length of 30 cm or more is required, a standardized cap nut is connected to cope with it. This eliminates the need for positioning work of the fixing plate at a work shop or the like, and also allows the combination body having a desired embedded length to be freely configured using a cap nut that can be mass-produced by standardization. Become. As a result, significant cost reduction can be expected in both the production of the members and the combination work. In addition, although the full length of the cap nut concerning this invention is arbitrary, when the ease of a process is considered, it is desirable to set it as about 15 cm thru | or 20 cm.

  In order to solve the above-mentioned problem, the invention described in claim 1 includes a base plate having a base through hole corresponding to a flange through hole provided in the flange plate, a cap nut having blind bolt holes at both ends, and a bag. Prepare a combined body consisting of a fixing plate attached to one end of the nut with mounting bolts, place the combined body at a predetermined position on the surface of the structure, and place reinforcing bars in the gap between the base plate and the surface of the structure After forming the installation structure in which the combined body was embedded by driving concrete or mortar in place, place the seismic isolation device on the base plate, and fix the cap bolt through the flange through hole and the base through hole. The technical means of fixing the seismic isolation device to the installation structure by screwing into the through bolt hole is adopted.

  In the present invention, the fixing plate is directly attached to the end portion of the cap nut in advance, so that the positioning operation of the fixing plate in the manufacturing process of the combined body at a work place or the like is not required. As a result, the assembly process at a work shop or the like is simplified, and the delivery time can be shortened and the operation cost can be reduced.

  Next, the invention described in claim 2 is the method for mounting the seismic isolation device described in claim 1, wherein in the combination, a plurality of cap nuts are connected by a slicing bolt to embed the length. It is characterized by extending. From a different viewpoint, when a buried length of 30 cm or more is required, instead of extending the cap nut of the conventional method in order to eliminate the need for anchor bolts, the cap nut is divided and manufactured in advance. And it can be said that it was integrated again.

  In such a configuration, since one cap nut can be standardized to a short length of about 15 cm, it can be easily manufactured with a simple small lathe possessed by many workshops. Also, by connecting the nuts one after another, the embedment length can be extended as necessary, and the cap nuts and slicing bolts for connecting them can be mass-produced in advance, so the cost per member can be reduced. . Further, since the positioning operation of the fixing plate is not required, the total cost of manufacturing the combined body can be reduced, and the delivery date and the work period can be shortened. The connecting nuts are not limited to the same length. For example, if the standard nuts of 10 cm, 15 cm, and 20 cm are manufactured in advance, and the connecting nuts having different lengths are connected as appropriate, the embedded length is set in units of 5 cm. Can be changed.

  Next, the invention described in claim 3 is the method for mounting the seismic isolation device described in claim 2, characterized in that, in the combination, the embedded length is at least 30 cm.

  The length from the structure side surface of the base plate to the fixing plate, that is, the required embedment length of the combination depends on the design of the structure, but is at least 15 cm, when the seismic isolation device is introduced into a relatively large building, etc. Is required to have a buried length of 30 cm or more. In the present invention, even when such an embedded length of 30 cm or more is required, the anchor bolt can be eliminated by connecting the cap nut and directly attaching the fixing plate to the terminal portion.

  Next, the invention described in claim 4 is the method of attaching the seismic isolation device according to any one of claims 1 to 3, wherein the rotation restraining plate is provided on the surface of the cap nut in the combination. It is characterized by providing.

  The installation structure is formed by pouring concrete or mortar into a formwork in which reinforcing bars are arranged and solidified, and is fixed integrally with an embedded combination. On the other hand, when fastening with a fixing bolt when installing the seismic isolation device, torque is applied to rotate the cap nut by tightening the fixing bolt, causing a gap between the cap nut and concrete or mortar. There is a risk of generating cracks around the cap nut. In order to prevent this, in the conventional construction method, before placing concrete or mortar into the formwork, separate reinforcing bars are provided between the reinforcing bars previously arranged in the installation structure and a part of the combined body, in particular between the cap nuts. Measures have been taken to suppress the rotation of the cap nut by welding directly, but this welding operation also increased the number of man-hours at the construction site.

  In the present invention, a small piece of steel plate is welded to the surface of the cap nut so as to rise vertically to the outside along the axial direction of the cap nut, and this is used as a rotation suppression plate. At the time of fastening with the fixing bolt, the rotation restraining plate projecting into the installation structure resists the torque against the torque to rotate the cap nut and restrains the rotation. This eliminates the need for the above-mentioned separate rebar and its welding work, and thus has the effect of reducing construction costs and shortening the construction period.

  Finally, the invention described in claim 5 is the seismic isolation device mounting method according to any one of claims 1 to 4, wherein one or more are provided on the surface of the cap nut in the combination. The fixing groove is provided.

  The cross section of the fixing groove preferably has an obtuse angle taper by inclining the inner wall on the base plate side, while the opposing inner wall is preferably shaped to be dug perpendicular to the rotation axis direction of the cap nut. Thereby, since the concrete or mortar easily enters the fixing groove when the installation structure is formed, it is possible to suppress a possibility that a void is generated in the fixing groove. Further, after the installation structure is formed, the inner wall on the opposite side exhibits the same resistance to pulling stress as the fixing plate with respect to the concrete or mortar that has entered the fixing groove and solidified.

A fixing plate may be attached even when a fixing groove is provided on the surface of the cap nut. However, if the total length of the connected cap nut is long, the fixing groove alone can exhibit sufficient resistance to pull-out stress. The fixing plate itself and the mounting bolt for attaching it to the terminal end of the cap nut can be omitted. If the fixing plate can be omitted, the possibility of interference with the reinforcing bars arranged in the installation structure is reduced, and the workability at the construction site is improved. It should be noted that excavation of the fixing groove on the surface of the cap nut is easy even with a popular small lathe, so that the cost does not increase significantly.

  According to the configuration of the present invention, (1) the fixing plate positioning work required in the conventional method is not required, so that the manufacturing cost of the combined body can be reduced and the delivery time can be shortened. The number of parts can be reduced and the cost of parts can be reduced. (3) Since the cap nut can be easily manufactured from a short steel bar with a popular type of small lathe owned by a general workshop, etc., there are technical restrictions on the manufacture of the parts. (4) Combination of standardized cap nuts and cutting bolts even if the required burial length for the installation structure of the combination differs depending on the design of the structure to be constructed. (5) The work on the construction site is not burdened by the action of the rotation restraining plate or the cap nut with fixing groove. The can enhance the fixation of the combination of the mounting structure, also expanding the degree of freedom in the mounting structure design, an effect such. As a result, the total cost of installing seismic isolation devices can be reduced, and as a result, through the popularization of seismic isolation devices, it can contribute to the creation of a city that is resistant to earthquakes.

EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated with reference to drawings.
(First embodiment)
FIG. 4 is an exploded view and a side view of members (excluding the base plate) used in the combination body 0 according to the first embodiment of the present invention. The member includes a cap nut 30, a fixing plate 40, a fixing bolt 50, a mounting bolt 60, and washers 70a and 70b. The cap nut 30 has blind bolt holes 30a and 30b having the same diameter and the same depth at both ends. Provided. Further, a rotation suppression plate 30c is welded to the side surface of the cap nut 30 so as to rise vertically along the axis. Even if one rotation suppression plate 30c has the effect of sufficiently suppressing the rotation of the cap nut 30, a plurality of rotation suppression plates 30c may be provided if necessary.

FIG. 5 is a member assembly diagram illustrating a cross-section in a state where the combination body 0 according to the first embodiment is attached to the flange plate 1. The flange plate 1 is provided with a flange through hole 1a, and the base plate 2 is provided with a base through hole 2a. Both through holes are simple through holes without threading. One end of the cap nut 30 is welded to the lower surface of the base plate 2 by a welding leg length 80. The flange through hole 1a, the base through hole 2a, and the blind bolt hole 30a have the same diameter, and the fixing bolt 50 is inserted from the flange plate 1 side through the washer 70a, and the tip is screwed into the blind bolt hole 30a. The flange plate 1, the base plate 2, and the cap nut 30 are integrally fastened and fixed. On the other hand, the fixing plate 40 is attached to the blind bolt hole 30b on the opposite side by a mounting bolt 60 and a washer 70b. The weld leg length 80 may be welded all around so as to make one round of the joint, but the base plate 2 and the cap nut 30 are originally fastened by the fixing bolt 50, and the welding itself has a strength that can sufficiently prevent the rotation of the member. Since it suffices to have one or a plurality of spot welds.

  FIG. 6 is an assembly process diagram in which steps for assembling the combination 0 in advance at a work shop or the like are divided into stages in the order of a, b, and c. First, in stage i, the fixing plate 40 is assembled to the other end of the cap nut with the mounting bolt 60 in advance. Next, in stage B, a jig 1 ′ having a through-hole having the same thickness as the flange plate 1 and the same diameter as the flange through-hole 1 a is placed on the upper surface of the base plate 2, and the fixing bolts are made after matching both through-holes. 50 is inserted, and the cap nut 30 is screwed into the fixing bolt 50 to be temporarily fixed, and then welded at the welding leg length 80. Finally, in Step C, when the fixing bolt 60 is removed and the jig 1 ′ is removed, the combined body 0 in which the members are welded to the base plate 2 is completed. The completed combination 0 is transported to the construction site as it is and used for construction. In the assembly process of such a combined body, as the fixing bolt 50, a bolt exclusively for temporary assembly having the same diameter and the same pitch may be used instead of the bolt actually used for mounting the seismic isolation device G.

  FIG. 7 is a perspective view showing a state in which each member is sequentially joined to the base plate 2 by the process shown in FIG. In FIG. 7, the base plate 2 has an annular shape with a work hole H provided therein, but the overall shape thereof may be circular, rectangular, or other depending on the design conditions of the seismic isolation device G and the structure. The work hole H serves as an access for work when the combination body 0 is disposed at a predetermined position, and an opening for driving concrete or mortar to form an installation structure.

FIG. 8 is a diagram showing a completed state in which the seismic isolation device G is attached to the foundation portion of the structure using the combination 0 in the seismic isolation device mounting method according to the first embodiment of the present invention.
Two sets of combinations 0 are attached to the upper and lower flange plates 1 of the seismic isolation device G in a vertically symmetrical form, and the members below the cap nut 30 are attached to the lower ends of the lower installation structure X and the upper structure as the upper installation structure. Is buried.

  By using a plurality of cap nuts 30 related to the combination body 0 according to the first embodiment, the embedded length of the combination body 0 can be appropriately extended. FIG. 9 is an exploded view of a member showing a case where the embedded length is extended by connecting the cap nuts 30 together. In this configuration, the two cap nuts 30 are connected via the dimension bolts 90, and the cap nut 30 can be additionally connected to further extend the embedded length.

(Second embodiment)
FIG. 10 is a member assembly diagram illustrating a cross-section in a state where the combination body 0 according to the second embodiment of the present invention is attached to the flange plate 1. In the fourth embodiment, not only the two cap nuts 31 are connected, but a plurality of fixing grooves 31a are provided on the surface of each cap nut. The cross section of the fixing groove 31a has an obtuse angle taper by inclining the inner wall on the base plate side, and the inner wall on the opposite side is dug perpendicularly to the rotation axis direction of the cap nut. Thereby, since the concrete or the mortar easily enters the fixing groove when the installation structure is formed, the possibility of generating a gap in the fixing groove 31a can be suppressed. In addition, after the installation structure is formed, the inner wall on the opposite side exhibits the same resistance to pulling stress as the fixing plate with respect to the concrete or mortar that has entered the fixing groove 31a and solidified.

Since the cap nut 31 according to the second embodiment exhibits the same pulling stress resistance as if it had a multistage fixing plate, the fixing plate 40 itself and the mounting bolt 60 can be omitted. Although the cost can be reduced by reducing the number of points, the fixing plate 40 may be attached without being omitted.

  As mentioned above, although the specific structure of several embodiment was demonstrated in detail about the attachment method of the seismic isolation apparatus which concerns on this invention, this invention is not limited to the said embodiment, The technical idea of this invention Within the scope of the present invention, improvements or modifications are possible and belong to the technical scope of the present invention.

  The present invention reduces the total cost of introducing a seismic isolation device by reducing the manufacturing cost of the constituent members of the combination used for attaching the seismic isolation device to a structure such as a building, further facilitating construction work. Is intended. In particular, in contrast to conventional methods that often require custom manufacturing of parts according to the required specifications such as the design of the structure, a combination body that can meet a variety of required specifications with only standardized members is used. Since it is possible to manufacture a combination body even in a workshop that does not have any material processing equipment, the installation method of the seismic isolation device according to the present invention contributes to the promotion of the spread of the seismic isolation device to a wide range of buildings, etc. It is possible.

Installation drawing of seismic isolation device by conventional construction method Exploded view and cross-sectional view of the combination body in the conventional construction method Cross-sectional view of the combination assembly in the conventional method Member exploded view and sectional view of the combination according to the first embodiment of the present invention Mounting sectional view of the combination according to the first embodiment of the present invention Manufacturing process diagram of the combination according to the first embodiment of the present invention The perspective view of the combination object concerning a first embodiment of the present invention. Seismic isolation device installation construction diagram according to the first embodiment of the present invention Sectional drawing of the member which shows the case where several cap nuts are connected in 1st embodiment of this invention Mounting sectional view of the combination according to the second embodiment of the present invention

G Seismic isolation device (laminated rubber part)
X Installation structure H Working hole 0 Combined body 1 Flange plate 1 'Jig 1a Flange hole 2 Base plate 2a Base hole 3 Cap nut (Conventional construction method)
4 Fixing plate (conventional construction method)
5 Mounting bolt (Conventional construction method)
6 Anchor bolt (conventional construction method)
7 Washer (conventional construction method)
8a-8c nut (conventional construction method)
9 Welding leg length (conventional construction method)
30 Cap nut (first embodiment)
31 Cap nut (second embodiment)
30a First blind bolt hole 30b Second blind bolt hole 30c Rotation restraint plate 31a Fixing groove
40 Fixing plate 50 Fixing bolt 60 Mounting bolt 70a, 70b Washer 80 Welding leg length 90 Dimming bolt

Claims (5)

  A seismic isolation device mounting method in which the upper and lower flange plates of a seismic isolation device are attached to a structure via a base plate, and a base plate having a base through-hole corresponding to the flange through-hole established in the flange plate and blinded at both ends. A combination body comprising a cap nut having a through bolt hole and a fixing plate attached to one end of the cap nut by a mounting bolt is prepared, and the base plate and the structure surface are arranged at a predetermined position on the structure surface. After placing the reinforcing bars in the gap between them and driving concrete or mortar into the installation structure in which the combination is buried, place the seismic isolation device on the base plate, and attach the fixing bolt to the flange through hole and The seismic isolation device is fixed to the installation structure by screwing into the blind bolt hole of the cap nut through the base through hole. Wherein the mounting method of the seismic isolation device.   The seismic isolation device mounting method according to claim 1, wherein in the combined body, the embedded length is extended by connecting a plurality of cap nuts with a dimension bolt.   The method for mounting a seismic isolation device according to claim 2, wherein, in the combined body, the embedded length is at least 30 cm or more.   The method for mounting a seismic isolation device according to any one of claims 1 to 3, wherein a rotation restraining plate is provided on a surface of the cap nut in the combined body.   The seismic isolation device mounting method according to any one of claims 1 to 4, wherein one or a plurality of fixing grooves are provided on a surface of the cap nut in the combined body.

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