JP2006257741A - Tool for placing rubber support - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tool for accurately placing a load on a base isolation member when the base isolation member is installed at site when an existing column is modified for base isolation and enabling a base isolating modification construction providing the sense of security with respect to strength. <P>SOLUTION: This tool comprises a base plate 10 having a hole 11 for shearing key formed at the upper surface center part thereof, a piston 20 having a shearing key 21 formed thereon for engagement with the hole 11, lower shoes 30 having cylinder holes 31 for storing the piston 20 formed at the lower surface center parts thereof and having a plurality of tapered grooves 32 with inclinations gradually increased in height toward its periphery radially formed on the outside of the cylinder hole 31, and a plurality of wedges 40 fitted to the tapered grooves 32 of the lower shoes 30. A fluid pressure is applied to the upper part of the piston 20 in the placed state of the lower shoes 30 on a rubber support 1. When the fluid pressure reaches a prescribed pressure, the wedges 40 are fixedly struck into the tapered grooves 32 of the lower shoes 30 while sliding them on the base plate 10 to support the load applied to the rubber support 1 by the wedges 40. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention belongs to the technical field of seismic retrofitting of an existing building, and particularly relates to a rubber bearing loading jig used when an existing building is seismically isolated using a rubber bearing.

Conventionally, seismic isolation structures applied to buildings are often applied not only to newly built buildings but also to seismic retrofitting (retrofit) of existing buildings. This is because the seismic isolation structure reduces the seismic input of the superstructure and reduces the need to modify the building body. As one of the seismic retrofitting methods for making such existing buildings seismic isolation, for example, as shown in Patent Document 1, there is known a seismic isolation load replacement method in which a rubber support as a seismic isolation member is installed on an existing pillar. It has been.
JP-A-10-246004

  In the method described in this document, a plurality of auxiliary piles are driven around a foundation pile of an existing building or a predetermined position on the foundation surface, and a first support jack is attached to the upper side of the auxiliary pile to support the building. The base pile and the building are separated, the auxiliary pile is fixed with a pressure board, a seismic isolation device is placed on the pressure board by combining a second support jack and an oil jack, and a second support jack. And the oil jack are adjusted so that the seismic isolation device is in close contact with the building and the oil jack is removed to fix the second support jack to the pressure board.

  Since the above-described seismic isolation load replacement method uses many jacks, the work at the site where these are handled becomes complicated. In addition, since a stud bolt for pull-out prevention is placed on the base plate of the rubber bearing, which is a seismic isolation device, and a support jack for changing the load after loading is necessary, it is difficult to provide a space for removing the oil jack. There is a problem. In addition, a plurality of oil jacks are arranged in the center part of the rubber bearing and a support jack is arranged in the outer peripheral part to support the load. Therefore, after removing the oil jack, the internal steel plate and the lower disc are made of rubber. There is a tendency that the center of the rubber bearing swells when pressed by the spring force of the plate. For this reason, since the stress distribution inside the rubber bearing is not uniform, anxiety remains after construction.

  The present invention has been made in view of such problems, and the object of the present invention is to facilitate handling on site when performing seismic isolation of existing columns, and rubber as a seismic isolation member. An object of the present invention is to provide a rubber bearing loading jig that can load a load evenly on a bearing and that enables earthquake-proof repair work with a sense of strength.

  In order to achieve the above object, the rubber support loading jig of the present invention is provided with a base plate provided with a hole for a shear key in the center of the upper surface, and a shear key that fits into the hole and restrains a horizontal force. And a lower rod with a plurality of tapered grooves radially provided on the outer side of the cylinder hole and having a slope that increases toward the periphery. A plurality of wedges that fit in the taper grooves of each, and with the rubber bearing resting on the lower collar, fluid pressure is applied to the top of the piston so that when it reaches a predetermined pressure, it slides on the base plate A feature is that the wedge is supported by the wedge by driving the wedge into the tapered groove of the lower rod and fixing it.

  When the rubber bearing loading jig of the present invention is used under a rubber bearing, the wedge is driven into the tapered groove and fixed when the fluid pressure applied to the upper part of the piston reaches a predetermined pressure. Since the applied load is supported by wedges, pressure management on site can be performed accurately. In addition, it is compact because it has a built-in jack, and the load applied to the rubber bearing is supported by wedges, so that an even force is applied to the inner steel plate and the lower disk of the rubber bearing. Can perform earthquake-proof repair work with a sense of security.

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

  1 is a longitudinal sectional view showing an example of a rubber bearing loading jig according to the present invention in an installed state, FIG. 2 is a sectional view taken along the line AB in FIG. 1, and FIG. 3 is a part in the direction C in FIG. It is sectional drawing. In addition, in FIGS. 1-3, the part of the mortar around the rubber | gum bearing loading jig | tool is represented with the dashed-dotted line.

  In the seismic retrofitting work, existing pillars are cut up and down and a rubber bearing is installed as a seismic isolation device between the separated pillars. The rubber bearing loading jig of the present invention has a rubber bearing as shown in FIG. It is installed on the lower side of the pillar that has been cut while supporting the support 1.

  As shown in FIGS. 1 and 2, the rubber support loading jig is fitted with a square base plate 10 provided with a hole 11 for a shear key at the center of the upper surface and the hole 11 to restrain the horizontal force. A disk-like piston 20 provided with a shear key 21 and a cylinder hole 31 for accommodating the piston 20 at the center of the lower surface are provided, and six cylinders with an inclination that increases toward the periphery are provided outside the cylinder hole 31. A disk-shaped lower rod 30 in which tapered grooves 32 are provided radially and six wedges 40 that fit into the tapered grooves 32 of the lower rod 30 are provided. As the base plate 10, a square plate is usually used, but a round plate may be used.

  A groove 33 is formed in the cylinder hole 31 of the lower rod 30 along the inner periphery, and an O-ring and a backup ring for preventing the protrusion thereof are housed in the groove 33. It is supposed to be. Further, as shown in FIG. 4, the piston 20 has a ring-shaped protruding portion 22 that is interrupted at four points in a perpendicular direction on the upper surface, and this protruding portion 22 contacts the bottom of the cylinder hole 31. In this state, a space is formed in the cylinder. The lower rod 30 is formed with an injection hole 34 and an air vent hole 35 leading to the space. With these configurations, the cylinder hole 31 of the lower rod 30 and the piston 20 fitted thereto form a jack portion.

  One side of the base plate 10 and the diameter of the lower collar 30 are the same size. Further, as shown in a partially enlarged view in FIG. 3, the lower collar 30 is provided with a flange portion 36 having a stepped outer periphery. The flange portion 36 is provided with a plurality of bolt holes for fixing to the base plate 10, and the upward force at the jack portion is supported by bolts passing through these bolt holes. Further, the injection hole 34 and the air vent hole 35 are provided from a vertical surface next to the flange portion 36.

  The construction procedure of the seismic retrofit method using the rubber bearing loading jig having the above-described configuration will be described as follows.

First, after supporting the load of the upper structure of the building using a jack, the pillar is cut and removed by a predetermined length to separate the pillar into an upper side and a lower side. And the mortar 2 is hit | damaged _first to the height h1 which installs the jig | tool for rubber | gum support loading with respect to the lower part side.

  Next, the rubber support loading jig is carried to the site. That is, the lower rod 30 is assembled with the piston 20 sandwiched on the base plate 10, and the lower rod 30 is carried to the site while being fixed to the base plate 10 with bolts passing through the bolt holes of the flange portion 36. Then, the jig for loading and supporting the rubber is horizontally installed on the mortar 2 previously hit on the lower side of the column, and the base plate 10 of the jig is fixed to the lower side of the column with the mortar. At the time of installation, the wedge 40 is inserted into the tapered groove 32 of the lower rod 30 in a loosely fitted state.

  Next, the rubber bearing 1 is placed on the installed rubber bearing loading jig and fixed to the lower bar 30 using bolts. An anchor frame 1 a is attached to the rubber support 1 on the upper side, and the anchor frame 1 a is fixed to the upper side of the pillar with a mortar 3.

Subsequently, after loosening the bolt of the flange portion 36 of the lower rod 30, hydraulic pressure or water pressure is applied to the upper portion of the piston 20 to increase to a predetermined pressure. In this case, oil or water is sent from the injection hole 34 provided in the lower rod 30 and air is expelled from the air vent hole 35. The pressure applied to the upper part of the piston 20 is about 250 to 700 kg / cm ² .

  When the predetermined pressure is reached, the wedge 40 is driven to such an extent that the pressure does not decrease. That is, a fluid pressure is applied to the upper portion of the piston 20 with the rubber support 1 placed on the lower rod 30, and when the pressure reaches a predetermined pressure, the taper groove of the lower rod 30 is slid on the base plate 10. The wedge 40 is driven into and fixed to 32, and the load applied to the rubber bearing 1 is supported. The wedge 40 is fixed by welding (41 in FIG. 1 indicates a welded portion).

  Next, the lower collar 30 is fixed to the base plate 10 by tightening the bolts of the flange portion 36 of the lower collar 30. At this time, as shown in FIG. 3, the lower collar 30 has a gap corresponding to the deflection of the rubber support 1 with respect to the base plate 10.

Thus, after supporting the load applied to the rubber bearing 1 with the wedge 40, the oil or water in the cylinder hole 31 is removed, and instead, grout is injected and hardened. Then, grout or mortar is also injected into the gap between the lower punch 30 and the base plate 10, and the mortar is further added to a height h ₂ at which the lower punch 30 is buried. Thus, after the rubber bearing loading jig is hardened with mortar, the load applied to it is released from the jack supporting the superstructure, the jack is removed, and the installation of the rubber bearing 1 is completed.

  As mentioned above, although the embodiment of the present invention has been described in detail, the rubber support loading jig according to the present invention is not limited to the above-described embodiment at all, and various modifications can be made without departing from the spirit of the present invention. Of course, it is possible to make changes.

It is sectional drawing of the vertical direction which shows an example of the rubber bearing loading jig | tool which concerns on this invention in an installation state. It is AB sectional drawing of FIG. It is a partial cross section figure in the C direction of FIG. It is the top view of a piston, and its XX sectional drawing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rubber support 1a Anchor frame 2,3 Mortar 10 Base plate 11 Hole 20 Piston 21 Shear key 22 Projection part 30 Lower rod 31 Cylinder hole 32 Tapered groove 33 Groove 34 Injection hole 35 Air vent hole 36 Flange part 40 Wedge 41 Weld part

Claims (1)

A base plate provided with a hole for a shear key in the center of the upper surface, a piston provided with a shear key that fits into the hole and restrains the horizontal force, and a cylinder hole that accommodates the piston in the center of the lower surface are provided. A lower ridge having a plurality of tapered grooves radially inclined toward the periphery on the outer side of the cylinder hole, and a plurality of wedges that respectively fit into the tapered grooves of the lower ridge, Applying fluid pressure to the upper part of the piston with the rubber bearing on top, and when it reaches the specified pressure, insert a wedge into the taper groove in the lower collar so that it slides on the base plate and secure it to the rubber bearing. A rubber bearing loading jig characterized by supporting the applied load with a wedge.

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