Seismic isolation structure

Abstract

To provide a seismic isolation structure that does not need to increase its vertical clearance to ensure its horizontal clearance at an end of a ramp in a width direction provided to connect a non-seismic isolation section and a seismic isolation section.SOLUTION: A seismic isolation structure 10 has a ramp 13 that is provided in a non-seismic isolation section 11 and is connected to a floor 33 of a seismic isolation section 12. The seismic isolation structure 10 comprises an expansion joint 16 at an end of the ramp 13 in a width direction. The expansion joint 16 extends vertically from the end of the ramp 13 in the width direction towards the floor 33, and has an end wall 37 with an upper end surface 37a extending horizontally, and a floor outer edge 40 that is arranged opposite on the upper end surface 37a of the end wall 37 with a clearance 38 having a predetermined vertical width L.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a seismic isolation structure having a ramp between a non-seismically isolated portion and a seismically isolated portion. [Background technology]

[0002] For example, as disclosed in Patent Document 1, in a seismic isolation structure, a non-seismically isolated portion and a seismically isolated portion are connected by an expansion joint having a clearance between them. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-037764 A Summary of the Invention [Problem to be solved by the invention]

[0004] In a seismic isolation structure, for example, a ramp that connects to the seismic isolation section is sometimes provided in the non-seismic isolation section. In such cases, a clearance that is inclined according to the gradient of the ramp is usually provided at the end of the ramp in the width direction, taking into consideration ease of construction. However, in this structure, it is necessary to increase the vertical clearance in order to ensure the horizontal clearance. [Means for solving the problem]

[0005] A seismic isolation structure that solves the above problem has a ramp provided in one of the seismic isolation section and the non-seismic isolation section and connected to the floor section of the other of the seismic isolation section and the non-seismic isolation section. The seismic isolation structure has an expansion joint at an end in a width direction of the ramp. The expansion joint is provided in one of the seismic isolation section and the non-seismic isolation section and has an end wall section extending in a vertical direction from the end in the width direction of the ramp toward the floor section, and a floor outer edge section that is part of the floor section and is arranged to face the end wall section with a clearance extending in a horizontal direction therebetween. Effect of the Invention

[0006] According to the present invention, it is not necessary to increase the vertical clearance in order to ensure the horizontal clearance. [Brief description of the drawings]

[0007] [Figure 1] 2 is a top view showing a schematic diagram of the positional relationship between the non-seismically isolated portion and the seismically isolated portion in one embodiment of a seismic isolation structure. FIG. [Diagram 2] FIG. 2 is a diagram showing a cross section taken along line 2-2 in FIG. [Diagram 3] FIG. 3 is a diagram showing a cross section taken along line 3-3 in FIG. 2. [Figure 4] 13 is a diagram showing a schematic diagram of a non-seismic isolation section and a seismic isolation section moving relative to each other in the horizontal direction. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] An embodiment of a seismic isolation structure will be described with reference to Figs. 1 to 4. FIG. 1 is a top view showing a schematic positional relationship between a non-seismic isolation section 11 and a seismic isolation section 12 in a seismic isolation structure 10. In FIG. 1, the light dotted parts are the non-seismic isolation section 11, and the dark dotted parts are the seismic isolation section 12. The seismic isolation structure 10 has a ramp 13 according to the difference in height between the non-seismic isolation section 11 and the seismic isolation section 12. In FIG. 1, the ramp 13 is hatched. In this embodiment, the ramp 13 is provided in the non-seismic isolation section 11. The ramp 13 is formed of, for example, vacuum concrete. The ramp 13 forms a gentle upward gradient leading to the seismic isolation section 12 from the right side to the left side in FIG. 1.

[0009] The seismic isolation structure 10 has an expansion joint 15 that connects the non-seismic isolation portion 11 and the seismic isolation portion 12 at the top of the ramp 13 (the left end of the ramp 13 in FIG. 1). The seismic isolation structure 10 also has an expansion joint 16 that connects the non-seismic isolation portion 11 and the seismic isolation portion 12 at the upper end of the ramp 13 in FIG. 1.

[0010] The expansion joint 16 is a first expansion joint, and the expansion joint 15 is a second expansion joint. In the following, the left-right direction in Fig. 1 is referred to as the extension direction of the ramp 13, and the up-down direction in Fig. 1 is referred to as the width direction of the ramp 13. The right side in the left-right direction in Fig. 1 is referred to as the base end side, and the left side is referred to as the tip end side.

[0011] FIG. 2 is a schematic cross-sectional view taken along line 2-2 in FIG. 2, the non-seismic isolation portion 11 is supported by a foundation 20. The seismic isolation portion 12 is supported by the foundation 20 via a seismic isolation device (not shown). The foundation 20 includes a foundation wall 21, partition walls 22, and the like.

[0012] The ramp 13 is supported by beams 23, 24 provided on the foundation 20 via bulkhead steel members 25 and a support base 26. The ramp 13 is formed of, for example, vacuum concrete.

[0013] The beams 23 extend in the extension direction of the ramp 13. The beams 23 are arranged in parallel in the width direction of the ramp 13 (see FIG. 3). The beam 24 extends in the width direction of the ramp 13 at a position higher than the beam 23 on the tip side of the beam 23.

[0014] The bulkhead steel material 25 is supported by the beams 23. The bulkhead steel material 25 is provided so as to follow the beams 23 (see FIG. 3). The bulkhead steel material 25 is formed in a generally U-shaped cross section with an open upper portion. The height of the bulkhead steel material 25 changes in the extension direction of the ramp 13 according to the height of the ramp 13.

[0015] The support base 26 is supported by the beams 23 from the base end to the tip end. The tip end of the support base 26 is supported by the beams 24. The support base 26 is made of, for example, concrete. The support base 26 supports the ramp 13 from below. A panel support part 28 is disposed in a recess formed at the tip end of the support base 26. The panel support part 28 is made of, for example, mortar.

[0016] The expansion joint 15 has a cover panel 30 and a rail 31. The cover panel 30 is provided so as to cover the clearance 34 between the floor 33 of the seismic isolation section 12 and the ramp 13. The rail 31 is supported on the outer edge of the floor 33. The rail 31 extends in the width direction of the ramp 13. The end of the cover panel 30 on the seismic isolation section 12 side is connected to the rail 31 so as to be movable along the width direction of the ramp 13. The cover panel 30 on the non-seismic isolation section 11 side is supported by a panel support section 28 provided on the non-seismic isolation section 11. The cover panel 30 is configured to be able to slide on the upper surface of the panel support section 28. That is, the expansion joint 15 is a one-sided rise type expansion joint in the extension direction of the ramp 13 and a rail slide type expansion joint in the width direction of the ramp 13.

[0017] Fig. 3 is a schematic cross-sectional view taken along line 3-3 in Fig. 2. As shown in Fig. 3, the support base 26 has a base portion 35, a protrusion portion 36, and an end wall portion 37 that are integrally formed from, for example, concrete.

[0018] The base portion 35 is formed in a rectangular shape when viewed from above so as to cover each of the bulkhead steel materials 25 from above. The base portion 35 is supported by the bulkhead steel materials 25. The base portion 35 is supported at its tip by the beam 24 (see FIG. 2).

[0019] One end of the base portion 35 in the width direction of the ramp 13 (the end on the expansion joint 16 side) is located below a floor outer edge portion 40 which is the outer edge of the floor portion 33. Hereinafter, the end of the base portion 35 located below the floor outer edge portion 40 will be referred to as the end wall side end portion.

[0020] The protrusion 36 protrudes downward from the base portion 35. The protrusion 36 is formed at a position corresponding to the bulkhead steel material 25 having a U-shaped cross section. The protrusion 36 extends within the groove of the bulkhead steel material 25 in the extension direction of the ramp 13.

[0021] The end wall portion 37 extends upward from the end wall side end of the base portion 35 toward the floor outer edge portion 40 of the floor portion 33 of the seismic isolation portion 12 so as to cover the gap between the ramp 13 and the floor portion 33. The upper end surface 37a of the end wall portion 37 extends horizontally in the direction in which the ramp 13 extends. The upper end surface 37a of the end wall portion 37 and the floor outer edge portion 40 of the floor portion 33 are disposed opposite each other with a clearance 38 of a vertical width L extending horizontally. The end wall portion 37 and the floor outer edge portion 40 constitute the expansion joint 16. The clearance 38 between the end wall portion 37 and the floor outer edge portion 40 may be covered by a cover panel (not shown).

[0022] (action) When the seismic isolation section 12 moves horizontally relative to the non-seismic isolation section 11, that relative movement is absorbed in the expansion joint 15 by the sliding of the cover panel 30 on the panel support section 28, the lifting of the cover panel 30 from the panel support section 28, and the movement of the cover panel 30 along the rail 31.

[0023] 4, in the expansion joint 16, the floor outer edge 40 of the floor 33 and the end wall 37 are disposed opposite each other via a horizontally extending clearance 38. Therefore, even if the seismic isolation section 12 moves horizontally relative to the non-seismic isolation section 11 as shown by the arrow in the figure, interference between the floor 33 and the end wall 37 is avoided regardless of the vertical width L of the clearance 38.

[0024] The effects of this embodiment will be described. (1) In the expansion joint 16, a clearance 38 extending horizontally is provided between the floor portion 33 and the end wall portion 37. This eliminates the need to increase the vertical clearance in order to ensure the horizontal clearance.

[0025] (2) Furthermore, since the non-seismic isolation section 11 and the seismic isolation section 12 do not interfere with each other at the expansion joint 16 during relative movement in the horizontal direction, the degree of freedom in designing the expansion joint 15, such as the size of the clearance, is improved.

[0026] (3) The expansion joint 15 has a rail 31 that is supported by the floor portion 33 and extends in the width direction of the ramp 13, and a cover panel 30 that is connected to the rail 31 so as to be movable along the rail 31 and covers the clearance between the non-seismic isolation portion 11 and the seismic isolation portion 12. This allows the cover panel 30 to smoothly follow the relative horizontal movement of the non-seismic isolation portion 11 and the seismic isolation portion 12 at the expansion joint 16.

[0027] (3) The ramp 13 is provided in the non-seismically isolated portion 11 and forms an upward gradient toward the floor portion 33. This allows the end wall portion 37 to be a wall portion that extends upward toward the outer edge portion 40 of the floor.

[0028] (4) The ramp 13 is supported from below by the base portion 35 of the support base 26. The end wall portion 37 is formed integrally with the base portion 35. This improves workability when forming the end wall portion 37, and allows the ramp 13 to be formed of vacuum concrete that has excellent surface strength, reduced cracking, and durability.

[0029] This embodiment can be modified as follows: This embodiment and the following modifications can be combined with each other to the extent that there is no technical contradiction. In the above embodiment, the ramp 13 is provided in the non-seismic isolation portion 11. However, the present invention is not limited to this, and the ramp 13 may be provided in the seismic isolation portion 12.

[0030] In the above embodiment, the ramp 13 forms an upward gradient toward the floor 33. However, the present invention is not limited to this, and the ramp 13 may form a downward gradient toward the floor 33. In the above embodiment, the end wall portion 37 extends upward toward the floor outer edge portion 40. However, the end wall portion 37 may extend downward depending on the positional relationship between the ramp 13 and the floor portion 33.

[0031] In the above embodiment, the expansion joint 16 has a configuration including the cover panel 30 and the rail 31. However, the expansion joint 16 is not limited to this, and may have any configuration as long as it covers the clearance between the ramp 13 and the floor 33 and can follow the relative movement between the non-seismic isolation portion 11 and the seismic isolation portion 12 in the horizontal direction.

[0032] The technical ideas that can be understood from the above-described embodiment and modified examples will be described. (Appendix 1) The ramp has a base portion that supports the ramp from below, and the end wall portion is formed integrally with the base portion. This improves workability when forming the end wall portion, and allows the ramp to be formed from vacuum concrete that has excellent surface strength, reduced cracking, and durability. [Explanation of symbols]

[0033] Reference Signs: 10...seismic isolation structure, 11...non-seismic isolation section, 12...seismic isolation section, 13...ramp, 15...expansion joint as second expansion joint, 16...expansion joint as first expansion joint, 20...foundation, 21...foundation wall, 22...stud, 23...beam, 24...beam, 25...raised steel, 26...support base, 28...panel support section, 30...cover panel, 31...rail, 33...floor section, 34...clearance, 35...base section, 36...protrusion section, 37...end wall section, 37a...upper end surface, 38...clearance, 40...outer edge section of floor.

Claims

1. A seismic isolation structure having a ramp provided in one of a seismic isolation section and a non-seismic isolation section and connected to a floor part of the other of the seismic isolation section and the non-seismic isolation section, An expansion joint is provided at an end in the width direction of the ramp, The expansion joint is An end wall portion provided in one of the seismic isolation portion and the non-seismic isolation portion and extending in a vertical direction from an end portion in a width direction of the ramp toward the floor portion; a floor outer edge portion that is a part of the floor portion and is arranged opposite to the end wall portion with a horizontally extending clearance therebetween; Earthquake-resistant structure.

2. the expansion joint is a first expansion joint, A second expansion joint is provided at an end portion of the ramp on the floor side in the extending direction thereof, The second expansion joint is A rail supported on the floor and extending in a width direction of the ramp; a cover panel connected to the rail so as to be movable along the rail and covering a clearance between the non-seismically isolated portion and the seismically isolated portion. The seismic isolation structure according to claim 1.

3. The ramp is provided in the non-seismically isolated portion and forms an upward gradient toward the floor portion, The end wall portion extends upwardly toward the outer edge of the floor. The seismic isolation structure according to claim 1 or 2.

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