Sliding bearing and structure

Abstract

To provide a sliding bearing capable of suppressing the application of a bearing pressure to a structure without complicating the structure, and to provide the structure.SOLUTION: A sliding bearing 1 is mounted to mounting base plates BP included in a structure B, and includes: shoes 20 including shoe-side sliding surfaces 21a, respectively; and a support 10 including a support-side sliding surface 10a contacting the shoe-side sliding surfaces 21a, for transmitting a load from the structure B to the shoes 20. Each of the shoe 20 includes: a plate-like first shoe member 21 formed with the shoe-side sliding surface 21a and a first contact surface 21b on a side opposite to the shoe-side sliding surface 21a; and a plate-like second shoe member 22 arranged on a side opposite to the support 10 on the first shoe member 21 and formed with a second contact surface 22a in surface-contact with the first contact surface 21b.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a sliding bearing and a structure.

Background Art

[0002] In a structure such as a building, a seismic isolation device may be provided in the structure so that the ground shaking during an earthquake does not transmit to the structure. Examples of the seismic isolation device include a sliding bearing and a laminated rubber bearing. A sliding bearing such as a spherical sliding bearing absorbs the earthquake shaking by relatively moving the structure horizontally with respect to the ground when an earthquake occurs. As a conventional example of such a sliding bearing, for example, there is one disclosed in Patent Document 1. In the spherical sliding bearing of Patent Document 1, a load transfer plate is provided between the spherical sliding bearing and the concrete foundation in order to reduce the stress intensity acting on the concrete foundation due to the load from the spherical sliding bearing. And, for the purpose of weight reduction and cost reduction, a net-like depression is formed in the load transfer plate.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the spherical sliding bearing of the above Patent Document 1, it is the structure on the side of the structure where the spherical sliding bearing is provided, not on the spherical sliding bearing side, that aims to reduce the surface pressure acting on the concrete structure. For this reason, there are the following problems. That is, there are problems such as the complication of the structure on the structure side because a load transfer plate is attached to the structure, and the need for the work of attaching the load transfer plate to the structure at the construction site, which makes the work at the construction site complicated. In general, a sliding bearing includes a shoe having a sliding surface and a support that relatively moves with respect to the shoe while being in contact with the sliding surface of the shoe, and supports the load of the structure with a support having a plan view size smaller than the plan view size of the entire sliding bearing. Therefore, when arranging a seismic isolation device in a predetermined plan view area of the structure, the sliding bearing tends to have a higher surface pressure applied to the structure than a laminated rubber bearing, and there is a problem that the applicable structures are likely to be limited.

[0005] The present disclosure has been made in view of the above-described circumstances, and an object thereof is to provide a sliding bearing and a structure that can suppress the surface pressure applied to the structure without complicating the structure.

Means for Solving the Problems

[0006] <1>The sliding bearing according to Aspect 1 of the present disclosure is a sliding bearing attached to a mounting base plate provided in a structure, and includes a shoe having a shoe-side sliding surface and a support body-side sliding surface that contacts the shoe-side sliding surface, and a support that transmits the load from the structure to the shoe. The shoe includes a plate-shaped first shoe member in which the shoe-side sliding surface is formed and a first contact surface is formed on the opposite side of the shoe-side sliding surface, and a plate-shaped second shoe member that is disposed on the opposite side of the support in the first shoe member and has a second contact surface that makes surface contact with the first contact surface.

Effects of the Invention

[0007] According to the present disclosure, it is possible to provide a sliding bearing and a structure that can suppress the surface pressure applied to the structure without complicating the structure.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, with reference to the drawings, a sliding bearing and a structure according to an embodiment of the present invention will be described. FIG. 1 is a front view of a sliding bearing provided in the structure according to the embodiment.

[0010] (Structure) The structure B according to the present embodiment is, for example, a part of a building such as a building, a warehouse, a house, a bridge, etc., and includes an upper structure B1 and a lower structure B2. The upper structure B1 is a portion supported by a plurality of sliding bearings 1, and includes, for example, a building-side portion of the foundation structure in a building. The lower structure B2 is a portion to which a load is transmitted from a plurality of sliding bearings 1, and includes, for example, a ground-side portion of the foundation structure in a building.

[0011] In this embodiment, the structure B includes a plurality of sliding bearings 1. As shown in FIG. 1, the sliding bearing 1 is provided between the upper structure B1 and the lower structure B2. Thus, the load of the upper structure B1 is transmitted to the lower structure B2 via the sliding bearing 1. At this time, the sliding bearing 1 forms a load dispersion region 20A in the soleplate 20 and transmits the load of the upper structure B1 to the lower structure B2 while dispersing it in the horizontal direction (details will be described later).

[0012] The structure B according to this embodiment includes a lower structure B2, and a mounting base plate BP is attached to the upper part of the lower structure B2. The sliding bearing 1 according to this embodiment is attached to this mounting base plate BP. That is, the structure B according to this embodiment includes a mounting base plate BP, and the sliding bearing 1 is attached to the mounting base plate BP provided in the structure B. The mounting base plate BP is arranged, for example, as shown in FIG. 1, with a part in the thickness direction embedded in the lower structure B2. Alternatively, the mounting base plate BP may be arranged with the entire thickness direction embedded in the lower structure B2.

[0013] By being provided between the sliding bearing 1 and the lower structure B2, the mounting base plate BP further disperses the load transmitted from the load dispersion region 20A of the sliding bearing 1 in the horizontal direction and transmits it to the lower structure B2. Here, if the sliding bearing 1 is directly attached to the lower structure B2 without passing through the mounting base plate BP, the load transmitted from the sliding bearing 1 to the lower structure B2 is locally added to the part of the lower structure B2 where the sliding bearing 1 is attached and its surroundings. In other words, the load from the sliding bearing 1 is not sufficiently dispersed and is transmitted to the lower structure B2. This may cause, for example, insufficient concrete strength in the part of the lower structure B2 where the sliding bearing 1 is attached.

[0014] By providing the mounting base plate BP between the sliding bearing 1 and the substructure B2, a load dispersion effect can be obtained by the thickness of both the second laminated member 22 (described later) in the sliding bearing 1 and the mounting base plate BP, so that the surface pressure applied to the concrete of the substructure B2 can be reduced, and the problem of insufficient strength of the concrete of the substructure B2 can be avoided. The mounting base plate BP is preferably changed in thickness and area depending on, for example, the strength of the concrete forming the substructure B2. Note that the area of the mounting base plate BP is the area of the surface of the mounting base plate BP facing the sliding bearing 1. For example, when the strength of the concrete is relatively low, it is preferable to reduce the surface pressure applied to the concrete by increasing the area and thickness of the mounting base plate BP. When the strength of the concrete is relatively high, the cost of the mounting base plate BP may be suppressed by reducing the area or thickness of the mounting base plate BP. Details of the shape of the mounting base plate BP will be described later in conjunction with the configuration of the sliding bearing 1.

[0015] (Sliding bearing) The sliding bearing 1 is provided between the superstructure B1 and the substructure B2. The sliding bearing 1 transmits the load of the superstructure B1 to the substructure B2. Further, the sliding bearing 1 relatively moves the superstructure B1 and the substructure B2 in the horizontal direction when an earthquake occurs in the structure B. By this, it is possible to suppress the displacement in the horizontal direction of the substructure B2 accompanying the vibration of the ground from being transmitted to the superstructure B1. As shown in FIG. 1, the sliding bearing 1 includes a support 10 and a laminate 20. In the present embodiment, the laminate 20 includes an upper laminate 20U and a lower laminate 20L. The support 10 is positioned so as to be sandwiched between the upper laminate 20U and the lower laminate 20L. That is, the sliding bearing 1 according to the present embodiment is a so-called double pendulum type spherical sliding bearing.

[0016] (Support) The support 10 moves horizontally while sliding with respect to the stack 20. By doing so, the upper structure B1 and the lower structure B2 can move relative to each other horizontally. Also, the support 10 transmits the load from the structure B to the stack 20. Specifically, the load transmitted from the upper structure B1 to the support 10 via the upper stack 20U is transmitted to the lower stack 20L. The support 10 is, for example, a disc-shaped member. The support 10 includes a support-side sliding surface 10a that contacts the stack-side sliding surface 21a (described later) provided on the upper stack 20U and the lower stack 20L. In the present embodiment, the support-side sliding surface 10a is a convex spherical surface. In the present embodiment, a pair of support-side sliding surfaces 10a are provided on both surfaces of the disc-shaped support 10.

[0017] (Stack) The stack 20 slides with respect to the support 10. In the present embodiment, the stack 20 is provided on the lower surface of the upper structure B1 and the upper surface of the lower structure B2, respectively. Hereinafter, the stack 20 provided on the lower surface of the upper structure B1 is referred to as the upper stack 20U. The stack 20 provided on the upper surface of the lower structure B2 is referred to as the lower stack 20L. When the upper stack 20U and the lower stack 20L are not distinguished, it is referred to as the stack 20. In the present embodiment, a pair of upper stack 20U and lower stack 20L are provided so as to sandwich the support 10. In the present embodiment, the upper stack 20U and the lower stack 20L have the same configuration as each other. Also, the upper stack 20U and the lower stack 20L are provided symmetrically with respect to the support 10. That is, the upper stack 20U and the lower stack 20L are arranged in a state of being inverted with respect to each other with the support 10 as the center. Hereinafter, the details of the lower stack 20L among the stacks 20 will be described. Since the upper stack 20U has the same configuration as the lower stack 20L, the description thereof will be omitted.

[0018] The lower stack 20L includes a first stack member 21 and a second stack member 22. The first stack member 21 contacts the support 10 and the second stack member 22. The second stack member 22 is disposed on the opposite side of the support 10 in the first stack member 21. The second stack member 22 contacts the first stack member 21 and the mounting base plate BP. The lower stack 20L transmits the load transmitted from the support 10 to the lower structure B2 via the mounting base plate BP. The load transmitted from the support 10 is the load transmitted from the upper structure B1 to the support 10 via the upper stack 20U.

[0019] (First stack member) The first stack member 21 is a disk-shaped member. In the present embodiment, the first stack member 21 is solid. This makes it easier to transmit the load by the first stack member 21, for example, as compared with the case where the first stack member 21 has a hollow structure such as a honeycomb structure. The first stack member 21 transmits the load transmitted from the support 10 to the second stack member 22.

[0020] As shown in FIG. 1, the first stack member 21 includes a stack-side sliding surface 21a and a first contact surface 21b. The stack-side sliding surface 21a is a surface that contacts the support-side sliding surface 10a of the support 10. That is, between the lower stack 20L and the support 10, the stack-side sliding surface 21a provided in the first stack member 21 and the support-side sliding surface 10a provided in the support 10 come into contact with each other and slide. Thus, the lower stack 20L and the support 10 move relative to each other in the horizontal direction. As described above, the support-side sliding surface 10a is a convex spherical surface. Correspondingly, the stack-side sliding surface 21a is a concave spherical surface. The stack-side sliding surface 21a is formed, for example, by cutting a disk-shaped member that forms the first stack member 21. It is preferable that the curvature of the support-side sliding surface 10a and the curvature of the stack-side sliding surface 21a are the same. Since the support-side sliding surface 10a and the stack-side sliding surface 21a are spherical surfaces with respect to each other, even when the lower stack 20L and the support 10 move relative to each other in the horizontal direction due to an earthquake, after the earthquake subsides, the support 10 returns to the center of the stack-side sliding surface 21a. Thus, after the earthquake, it is possible to eliminate the need to perform work such as correcting the relative position between the lower stack 20L and the support 10. The first contact surface 21b is located on the side opposite to the sliding surface 21a of the stack. The first contact surface 21b is the portion of the first stack member 21 that is in surface contact with the second contact surface 22a of the second stack member 22. In this embodiment, the first contact surface 21b and the second contact surface 22a are in contact with each other in all regions of the overlapping region in the direction of their arrangement, excluding the bolt joint portion, but may have portions that are not in contact in some regions other than the bolt joint portion.

[0021] (Second stack member) The second stack member 22 is a disk-shaped member. In this embodiment, the second stack member 22 is solid. This makes it easier to transmit the load by the second stack member 22, for example, as compared with the case where the second stack member 22 has a hollow structure such as a honeycomb structure. The second stack member 22 is disposed on the side opposite to the support 10 in the first stack member 21. The second stack member 22 transmits the load transmitted from the support 10 through the first stack member 21 to the mounting base plate BP. That is, the second stack member 22 is the portion of the lower stack 20L that contacts the mounting base plate BP.

[0022] Figure 2 is a cross-sectional view taken along the II-II direction in Figure 1. Figure 3 is a view showing a state in which the upper structure B1 and the lower structure B2 of the structure B shown in Figure 1 move relative to each other in the horizontal direction. In this embodiment, as shown in Figure 2, the area of the second stack member 22 when viewed from the side facing the first stack member 21 is larger than the area of the first stack member 21 when viewed from the same side. Hereinafter, the portion located outside the outer edge of the first stack member 21 when viewed from the side where the first stack member 21 is located along the alignment direction, which is the direction in which the first stack member 21 and the second stack member 22 are aligned in the second stack member 22, is referred to as the edge portion 22E. In other words, in this embodiment, the second stack member 22 includes the edge portion 22E. When viewed from the alignment direction, the edge portion 22E of the second stack member 22 is annular. That is, the overhang of the outer edge of the second stack member 22 from the outer edge of the first stack member 21 is uniform over the circumferential direction of the second stack member 22. By doing this, when receiving the load from the first stack member 21 and when transmitting the load to the mounting base plate BP, it is possible to prevent unevenness in load dispersion or the like in the circumferential direction of the second stack member 22. Further, for example, as shown in FIG. 3, even when the support 10 moves horizontally relative to the first stack member 21 due to an earthquake and the support 10 moves near the outer edge of the first stack member 21, the second stack member 22 can be provided with a sufficient load dispersion region 20A. Therefore, even when the support 10 moves near the outer edge of the first stack member 21, the load can be sufficiently dispersed. Also, in the present embodiment, as shown in FIG. 1, the thickness of the second stack member 22 is thicker than the thickness of the first stack member 21. By this, a load dispersion region 20A of a sufficient size can be formed by the thickness of the second stack member 22, and it is possible to more reliably and easily perform load dispersion.

[0023] The second stack member 22 having the above-described shape includes, as shown in FIGS. 4, 5, 6, and 7, a second contact surface 22a, a load transmission surface 22b, a positioning portion 22c, a second through hole 22d, a first fastening hole 22e (corresponding to the fastening hole of the present invention), and a second fastening hole 22f. The second contact surface 22a is a portion that is in surface contact with the first contact surface 21b of the first stack member 21. That is, the second contact surface 22a is flat like the first contact surface 21b of the first stack member 21. The load transmission surface 22b is a portion that is in surface contact with the mounting base plate BP in a state where the sliding support 1 is installed on the structure B. The load transmission surface 22b is, for example, flat.

[0024] FIG. 4 is an enlarged cross-sectional view showing a first example of the positioning portion 22c. FIG. 5 is an enlarged cross-sectional view showing a second example of the positioning portion 22c. The positioning portion 22c is provided for horizontally positioning the first stack member 21 with respect to the second stack member 22. In the present embodiment, the following two examples of the positioning portion 22c can be mentioned. As shown in FIG. 4, the first example of the positioning portion 22c is a recess formed in the second stack member 22 in a shape corresponding to the contour shape of the first contact surface 21b. In this case, the alignment between the first stack member 21 and the second stack member 22 is performed by fitting the first stack member 21 into the positioning portion 22c which is a recess. Note that the recess in the second stack member 22 may be formed by any method. As shown in FIG. 5, the second example of the positioning portion 22c is a protruding portion protruding from the second contact surface 22a. In this case, the alignment between the first stack member 21 and the second stack member 22 is performed by abutting the first stack member 21 against the positioning portion 22c which is a protruding portion. Note that the protruding portion is formed, for example, by joining a plate-shaped or block-shaped member to the upper surface of the second stack member 22 by welding or the like. Alternatively, the protruding portion may be formed by cutting a disc-shaped member forming the second stack member 22 while leaving the protruding portion. Further, it is preferable that a plurality of protruding portions are provided at intervals along the circumferential direction of the first stack member 21 in the second stack member 22.

[0025] FIG. 6 is an enlarged cross-sectional view showing the first through hole BPH and the second through hole 22d. The second through hole 22d is a hole penetrating the second stack member 22 in the vertical direction. That is, the second through hole 22d penetrates the second stack member 22 across the load transmission surface 22b and the second contact surface 22a. The second stack member 22 is formed to vent air from the concrete placed below the second stack member 22. The second through hole 22d is preferably provided at the edge 22E of the second stack member 22, as shown in FIGS. 2 and 6, for example. The second through hole 22d communicates with the first through hole BPH provided in the mounting base plate BP (details will be described later).

[0026] FIG. 7 is an enlarged cross-sectional view showing the first fastening hole 22e and the second fastening hole 22f. As shown in Fig. 7, the first fastening hole 22e is a through-hole through which a first fastening member F1 (corresponding to the fastening member of the present invention) for joining the first stack member 21 and the second stack member 22 is inserted. The first fastening member F1 is, for example, a known bolt. The first fastening hole 22e penetrates the second stack member 22 in the vertical direction. At this time, the first fastening hole 22e preferably includes a first diameter portion 22e1 that can accommodate the head of the first fastening member F1 and a second diameter portion 22e2 through which only the threaded portion of the first fastening member F1 can be inserted. That is, the first fastening hole 22e is preferably formed to be recessed from the load transmission surface 22b toward the second contact surface 22a. As shown in Figs. 2 and 7, the first fastening hole 22e is provided in a portion of the second stack member 22 that overlaps the first stack member 21 when viewed from the side facing the first stack member 21. In other words, the first fastening hole 22e is provided in a portion of the second stack member 22 other than at least the edge portion 22E.

[0027] In the present embodiment, as shown in Fig. 7, the first stack member 21 and the second stack member 22 are joined by the first fastening member F1. The first fastening member F1 is inserted into the first fastening hole 22e formed in the second stack member 22 and protrudes from the second contact surface 22a, and is arranged in a state where the protruding portion is located inside the first stack member 21. Therefore, it is preferable that a screwing portion 21S that can be screwed with the first fastening member F1 is formed in the first stack member 21.

[0028] As shown in Fig. 7, the second fastening hole 22f is a through-hole through which a second fastening member F2 for joining the second stack member 22 and the mounting base plate BP is inserted. The second fastening hole 22f penetrates the second stack member 22 in the vertical direction. The inner diameter of the second fastening hole 22f may be constant, for example, in the vertical direction. Alternatively, a portion having a diameter sufficient to accommodate the head of the second fastening member F2 for joining the second stack member 22 and the mounting base plate BP may be formed at the upper portion of the second fastening hole 22f. As shown in FIGS. 2 and 7, for example, the second fastening hole 22f is provided at the edge 22E of the second stack member 22. At this time, it is preferable that the second fastening hole 22f does not interfere with the second through hole 22d also provided at the edge 22E. That is, for example, the second fastening hole 22f and the second through hole 22d are preferably formed to be arranged alternately in the circumferential direction of the second stack member 22.

[0029] (Load dispersion region) In the present embodiment, the lower stack 20L forms a load dispersion region 20A by the first stack member 21 and the second stack member 22. The load dispersion region 20A is a virtual region. As shown in FIG. 1, the load dispersion region 20A is formed to radially expand from the side facing the support 10 to the side facing the lower structure B2 in the lower stack 20L. In other words, the load transmitted from the support 10 to the lower stack 20L is transmitted to the lower structure B2 while being diffused horizontally in the load dispersion region 20A. By this, the load dispersion region 20A in the lower stack 20L increases the area of the lower structure B2 receiving the load when transmitting the load added from the support 10 to the lower structure B2. By this, the load dispersion region 20A reduces the surface pressure applied to the lower structure B2. This contributes to lengthening the durability period of the lower structure B2.

[0030] The load dispersion region 20A is defined in a substantially frustum - cone shape within the lower stack 20L, for example, in a state where the support 10 and the stack 20 are not moving relative to each other in the horizontal direction as shown in FIG. 1. The upper bottom surface of the load dispersion region 20A is the surface that contacts the support 10 among the sliding surfaces 21a on the stack side of the first stack member 21 provided in the lower stack 20L. The lower bottom surface of the load dispersion region 20A is the surface that contacts the mounting base plate BP of the load dispersion region 20A. Note that in the state where the support 10 and the stack 20 shown in FIG. 1 are not moving relative to each other in the horizontal direction, the first stack member 21 in the upper stack 20U and the first stack member 21 in the lower stack 20L are facing each other, and the central axes of the sliding surfaces 21a on the stack side of each of the lower stack 20L and the upper stack 20U coincide with the central axis of the sliding surface 10a on the support side of the support 10. The load dispersion region 20A is dispersed with a predetermined spread angle A in a state where the support 10 and the stack 20 are not moving relative to each other in the horizontal direction as shown in FIG. 1. The spread angle A refers to the angle with respect to the vertical direction when the load dispersion region 20A spreads from the side of the support 10 toward the side of the mounting base plate BP as shown in FIG. 1. The spread angle A is the angle formed by a virtual line extending from the outer peripheral edge of the upper bottom surface of the load dispersion region 20A toward the side of the mounting base plate BP and the outer peripheral surface (boundary surface) of the load dispersion region 20A in a predetermined cross-sectional view. The outer peripheral surface (boundary surface) of the load dispersion region 20A is formed, for example, so as to connect the outer edges of the upper bottom surface and the lower bottom surface of the load dispersion region 20A in plan view in a planar manner. The cross-section according to the predetermined cross-sectional view is a vertical cross-section passing through the center of the support 10. The spread angle A is preferably uniform in any cross-section passing through the center of the support 10.

[0031] The spread angle A of the load dispersion region 20A is set, for example, by the rigidity and material strength of the first stack member 21 and the second stack member 22. If the rigidity and material strength of the first stack member 21 and the second stack member 22 are low, the first stack member 21 and the second stack member 22 are deformed by the surface pressure applied from the support 10. For this reason, the spread angle A of the load dispersion region 20A becomes small, and it becomes difficult to reduce the surface pressure transmitted to the lower structure B2. If the rigidity and material strength of the first stack member 21 and the second stack member 22 are high, the spread angle A of the load dispersion region 20A becomes large, and it becomes easy to reduce the surface pressure transmitted to the lower structure B2.

[0032] The size of the load dispersion region 20A is set, for example, by the size of the spread angle A and the thicknesses of the first stack member 21 and the second stack member 22. Here, the size of the load dispersion region 20A refers to the size when the sliding bearing 1 is viewed in plan view. The size of the load dispersion region 20A is the largest at the lower end of the second stack member 22. The larger the thickness of the lower stack 20L, the larger the load dispersion region 20A. That is, the larger the thickness of the lower stack 20L, the smaller the surface pressure transmitted to the mounting base plate BP can be.

[0033] The size of the load dispersion region 20A may be set according to the areas of the first stack member 21 and the second stack member 22 in plan view. Increasing the areas of the first stack member 21 and the second stack member 22 is effective, for example, when the areas of the first stack member 21 and the second stack member 22 are small with respect to the spread angle A of the load dispersion region 20A, and the function of reducing the surface pressure transmitted to the mounting base plate BP cannot be fully utilized. Alternatively, if the thicknesses of the first stack member 21 and the second stack member 22 are excessively large, a tipping moment may occur with respect to the lower stack 20L. To prevent this, the areas of the first stack member 21 and the second stack member 22 may be increased.

[0034] Note that the load dispersion region 20A deforms as shown in FIG. 3 when the support 10 and the stack 20 move relative to each other in the horizontal direction due to an earthquake. It is preferable that the stack 20 and the mounting base plate BP have a shape such that all of the load dispersion region 20A fits inside the stack 20 even when the load dispersion region 20A, which is a virtual region, deforms due to an earthquake.

[0035] (Mounting base plate) Next, the mounting base plate BP provided on the structure B will be described. The mounting base plate BP is, for example, a disk-shaped member. However, the mounting base plate BP is not limited to a disk shape and may be, for example, a square plate shape (rectangular plate shape). The mounting base plate BP is provided between the stack 20 and the structure B. Specifically, the mounting base plate BP is provided, for example, between the second stack member 22 provided in the lower stack 20L and the lower structure B2. The mounting base plate BP transmits the load transmitted from the second stack member 22 of the lower stack 20L to the lower structure B2. In the present embodiment, the mounting base plate BP is embedded, for example, in the concrete forming the lower structure B2 as shown in FIG. 1. Alternatively, it may be arranged on the concrete forming the lower structure B2.

[0036] In the present embodiment, as shown in FIG. 2, when the mounting base plate BP is viewed from the thickness direction, the area of the outer peripheral circle of the mounting base plate BP is larger than the area of the second stack member 22 when viewed from the thickness direction. Hereinafter, in the mounting base plate BP, when viewed from the side where the second stack member 22 is located along the direction in which the second stack member 22 and the mounting base plate BP are aligned, the portion located outside the outer edge of the second stack member 22 is referred to as the edge portion BPE. In other words, in the present embodiment, the mounting base plate BP includes the edge portion BPE. When viewed from the side facing the second stack member 22 of the mounting base plate BP, the edge portion BPE of the mounting base plate BP is annular. That is, the overhang of the outer edge of the mounting base plate BP from the outer edge of the second stack member 22 is uniform over the circumferential direction of the mounting base plate BP. By this, when receiving the load from the second stack member 22 and when transmitting the load to the mounting base plate BP, it is possible to prevent unevenness in the dispersion of the load in the circumferential direction. Further, for example, as shown in FIG. 3, even when the support 10 moves horizontally relative to the stack 20 due to an earthquake and the support 10 moves near the outer edge of the first stack member 21, it is possible to prevent the load dispersion region 20A from being located outside the mounting base plate BP. Therefore, even when the support 10 moves near the outer edge of the first stack member 21, the load can be sufficiently dispersed.

[0037] Also, in the present embodiment, the thickness of the second stack member 22 is thicker than the thickness of the mounting base plate BP. By this, a load dispersion region 20A of a sufficient size can be formed by the thickness of the second stack member 22, and it is possible to more reliably and easily perform the dispersion of the load. In the present embodiment, as shown in FIG. 7, the second stack member 22 is fastened to the mounting base plate BP by a second fastening member F2. The second fastening member F2 that joins the second stack member 22 and the mounting base plate BP is inserted through, for example, a second fastening hole 22f and fastened to the mounting base plate BP. For this reason, it is preferable that a screwing portion BPS that can be screwed with the second fastening member F2 is formed in the mounting base plate BP.

[0038] Here, as described above, the mounting base plate BP is disposed in the concrete forming the lower structure B2. When forming the lower structure B2, the concrete may be placed under the previously disposed mounting base plate BP. At this time, if air remains between the lower surface of the mounting base plate BP and the concrete, a gap may occur between the mounting base plate BP and the concrete after the concrete hardens. If there is a gap between the mounting base plate BP and the concrete, the contact area between the mounting base plate BP and the concrete decreases, which causes an increase in the surface pressure when transmitting the load. Therefore, the mounting base plate BP is provided with a first through hole BPH penetrating in the vertical direction in order to remove air from the concrete placed under the mounting base plate BP. The first through hole BPH is provided, for example, at the edge BPE of the mounting base plate BP as shown in FIG. 2. Alternatively, the first through hole BPH may be provided so as to communicate with a second through hole 22d provided at the edge 22E of the second laminated member 22 as shown in FIG. 7. By doing so, the air remaining in the concrete is allowed to escape through the first through hole BPH and the second through hole 22d, thereby suppressing the occurrence of a gap between the mounting base plate BP and the concrete.

[0039] (Modification example of the mounting base plate) FIG. 8 is a schematic front view of the structure B showing a modification example of the mounting base plate BP. FIG. 9 is a cross-sectional view taken along the line IX-IX in FIG. 8. The structure B includes a plurality of sliding bearings 1. As a result, when the structure B also includes a plurality of mounting base plates BP, not all of the mounting base plates BP have to be the same. For example, as a modification example of the mounting base plate BP, the following may also be used. That is, as shown in FIGS. 8 and 9, the mounting base plate BP according to the modification example may be annular when viewed from the side facing the second stacked member 22 of the mounting base plate BP. Also in this case, it is preferable that the mounting base plate BP includes an edge portion BPE. Further, it is preferable that the mounting base plate BP secures a region that is in surface contact with the load transmission surface 22b of the second stacked member 22. Thereby, the second stacked member 22 and the mounting base plate BP can be reliably joined. In the illustrated example, the mounting base plate BP is circular and annular, but it may be rectangular and annular.

[0040] (Form during transportation of the sliding bearing) Next, the form during transportation of the sliding bearing 1 according to the present embodiment will be described. FIG. 10 is a first example of the form of transporting the sliding bearing 1. FIG. 11 is a second example of the form of transporting the sliding bearing 1. The sliding bearing 1 having each of the above-described configurations is transported in a state where the upper stack 20U, the lower stack 20L, and the support 10 are combined with each other. Therefore, when transporting the sliding bearing 1, it is necessary to prevent the positions of the upper stack 20U and the lower stack 20L from shifting relative to each other. Therefore, the sliding bearing 1 according to the present embodiment further includes a fixing jig J during transportation as shown in FIGS. 10 and 11. The fixing jig J fixes the pair of stacked members 20, that is, the upper stack 20U and the lower stack 20L, to each other when transporting the sliding bearing 1.

[0041] The fixing jig J is, for example, a plate-like member as shown in FIG. 10. In this case, the fixing jig J is fixed to the respective side surfaces of the upper stack 20U and the lower stack 20L by a third fastening member F3 or the like. This restricts the relative movement between the upper stack 20U and the lower stack 20L. Alternatively, the fixing jig J may be, for example, a clamp-like member as shown in FIG. 11. In this case, the fixing jig J may be fixed in contact with the second stacked members 22 provided in the upper stack 20U and the lower stack 20L, respectively, and sandwiching the sliding bearing 1 in the thickness direction of the stacked members 20.

[0042] As described above, according to the sliding bearing 1 according to the present embodiment, it is attached to the mounting base plate BP provided in the structure B, and includes the sole 20 and the support 10. The support 10 transmits the load from the structure B to the sole 20. The sole 20 includes a first sole member 21 that contacts the support 10 and a second sole member 22 that is disposed on the opposite side of the support 10 in the first sole member 21. By configuring the sole 20 in this way, the load transmitted from the support 10 to the sole 20 is first transmitted from the support 10 to the first sole member 21 via the sole-side sliding surface 21a, and then from the first sole member 21 to the second sole member 22 via the second contact surface 22a. In this way, by providing a plurality of configurations for transmitting the load, the load transmitted from the structure B to the sole 20 can be transmitted to the mounting base plate BP in a sufficiently dispersed state. That is, the second sole member 22 can form a load dispersion region 20A that disperses the load transmitted from the support 10 in the sliding bearing 1. This can reduce the surface pressure applied to the mounting base plate BP from the sliding bearing 1. Therefore, for example, the variety of structures B to which the sliding bearing 1 can be applied can be increased. In addition, the durability period of the structure B can be extended. Further, according to the above-described structure, it is possible to reduce the surface pressure acting on the structure B without complicating the structure B. Therefore, for example, the work at the construction site can be simplified.

[0043] Further, the second sole member 22 includes a load transmission surface 22b that is in surface contact with the mounting base plate BP in a state where it is installed on the structure B. Thereby, it is possible to more efficiently transmit the load transmitted from the support 10 to the mounting base plate BP.

[0044] Further, the sliding surface 21a on the block side is a concave spherical surface, and the sliding surface 10a on the support side is a convex spherical surface. That is, the sliding bearing 1 is a so-called spherical sliding bearing. Thereby, for example, when an earthquake occurs in the structure B provided with the sliding bearing 1, the support 10 and the block 20 move relative to each other in the horizontal direction, so that the structure B can be moved relative to the ground in the horizontal direction and the shaking of the earthquake can be absorbed. And after the earthquake, the position of the structure B can be restored to the position before the earthquake without performing a position correction operation or the like.

[0045] Further, the second block member 22 includes an edge portion 22E that is located outside the outer edge of the first block member 21 when viewed from the side where the first block member 21 is located along the arrangement direction, which is the direction in which the first block member 21 and the second block member 22 are arranged. That is, the outer edge of the second block member 22 is located outside the outer edge of the first block member 21. In other words, when the sliding bearing 1 is viewed from the side facing the first block member 21 of the second block member 22, the area of the second block member 22 is larger than the area of the first block member 21. Thereby, for example, even when the support 10 moves relative to the first block member 21 in the horizontal direction due to an earthquake and the support 10 moves near the outer edge of the first block member 21, the second block member 22 can be provided with a sufficient load dispersion region 20A. Therefore, even when the support 10 moves near the outer edge of the first block member 21, the load can be sufficiently dispersed.

[0046] Further, when viewed from the arrangement direction, the edge portion 22E of the second block member 22 is annular. That is, the overhang of the outer edge of the second block member 22 from the outer edge of the first block member 21 is uniform over the circumferential direction of the second block member 22. Thereby, when the support 10 moves near the outer edge of the first block member 21, the load can be sufficiently dispersed to the second block member 22 regardless of the direction in which the support 10 moves relative to the first block member 21.

[0047] Further, a pair of blocks 20 are provided so as to sandwich the support 10. That is, the sliding bearing 1 is a spherical sliding bearing of a method called a so-called double pendulum. Thereby, for example, the range in which the structure B can move in the horizontal direction relative to the ground can be increased.

[0048] Further, it further includes a fixing jig J for fixing the pair of washers 20 provided in a pair to each other. Thereby, for example, when the sliding bearing 1 is shipped, it is possible to suppress the positions of the pair of washers 20 provided in a pair from shifting from each other. Therefore, it is possible to efficiently carry the sliding bearing 1, which is a spherical sliding bearing of the double pendulum type, to the construction site.

[0049] Further, the second washer member 22 is solid. Thereby, for example, compared with the case where the second washer member 22 has a hollow structure such as a honeycomb structure, it is possible to easily perform load transmission and dispersion by the second washer member 22.

[0050] Further, the second washer member 22 includes a second through hole 22d penetrating across the load transmission surface 22b and the second contact surface 22a. Thereby, it is possible to suppress air bubbles from remaining in the concrete placed below the second washer member 22. Therefore, it is possible to suppress the generation of a cavity between the lower surface of the second washer member 22 and the concrete. Therefore, the load can be more reliably transmitted from the second washer member 22 to the concrete placed below the second washer member 22.

[0051] Further, the thickness of the second washer member 22 is thicker than the thickness of the first washer member 21. By this, for example, while suppressing the thickness of the first washer member 21, the thickness of the entire washer 20 can be ensured, and the load dispersion region 20A can be enlarged. That is, by ensuring the thickness of the entire washer 20, the load transmitted from the support 10 to the washer 20 can be sufficiently easily dispersed. Further, by suppressing the thickness of the first washer member 21, it is possible to easily perform operations such as processing for forming the first washer member 21. That is, for example, when the washer-side sliding surface 21a provided in the first washer member 21 is a concave spherical surface, it is possible to easily perform the operation of cutting the first washer member 21.

[0052] Further, the first stack member 21 and the second stack member 22 are joined by a first fastening member F1. Thereby, for example, when an earthquake occurs in the structure B provided with the sliding bearing 1, it is possible to suppress the displacement of the positions of the first stack member 21 and the second stack member 22.

[0053] Further, the first fastening member F1 is inserted into a first fastening hole 22e formed in the second stack member 22 so as to be recessed from the load transmission surface 22b toward the second contact surface 22a, and protrudes from the second contact surface 22a, and the protruding portion is disposed in a state of being located inside the first stack member 21. Thereby, the first fastening member F1 can be prevented from being located outside the stack 20. Therefore, for example, when an operator inspects the sliding bearing 1 or the like, it is possible to prevent the operator from contacting the first fastening member F1.

[0054] Further, the second stack member 22 includes a positioning portion 22c that positions the first stack member 21 in the horizontal direction with respect to the second stack member 22. Thereby, it is possible to easily align the relative positions of the first stack member 21 and the second stack member 22 in the horizontal direction.

[0055] Further, the positioning portion 22c is a recess formed in the second stack member 22 in a shape corresponding to the contour shape of the first contact surface 21b. Thereby, for example, by fitting the first stack member 21 into the recess, the relative positions of the first stack member 21 and the second stack member 22 can be aligned.

[0056] Further, the positioning portion 22c may be a protruding portion that protrudes from the second contact surface 22a. Thereby, for example, by bringing the first stack member 21 into contact with the protruding portion, the relative positions of the first stack member 21 and the second stack member 22 can be aligned.

[0057] Further, according to the structure B according to the present embodiment, the sliding bearing 1 according to the present embodiment is provided. Thereby, it is possible to keep the surface pressure due to the load transmitted from the sliding bearing 1 to the structure B low. Therefore, for example, the types of the structure B can be diversified. In addition, the durability period as the structure B can be extended.

[0058] Further, the mounting base plate BP includes an edge portion BPE that is located outside the outer edge of the second stack member 22 when viewed from the side where the second stack member 22 is located along the direction in which the second stack member 22 and the mounting base plate BP are arranged. That is, the outer edge of the mounting base plate BP is located outside the outer edge of the second stack member 22. In other words, when the sliding bearing 1 provided on the structure B is viewed from the side facing the second stack member 22 of the mounting base plate BP, the area of the mounting base plate BP is larger than the area of the second stack member 22. Thereby, for example, even when the support 10 moves horizontally relative to the stack 20 due to an earthquake and the support 10 moves near the outer edge of the first stack member 21, the load dispersion region 20A can be prevented from being located outside the mounting base plate BP. Therefore, even when the support 10 moves near the outer edge of the first stack member 21, the load can be sufficiently dispersed.

[0059] Also, the thickness of the second stack member 22 is thicker than the thickness of the mounting base plate BP. By this, the thickness of the mounting base plate BP can be suppressed. Also, by making it easier to secure the thickness of the second stack member 22, it becomes easier to form the load dispersion region 20A of the second stack member 22. Therefore, for example, it is possible to sufficiently disperse the load from the structure B. Also, while securing the area of the mounting base plate BP, the volume of the mounting base plate BP can be suppressed. Therefore, the cost of the mounting base plate BP can be suppressed.

[0060] Also, the edge portion BPE of the mounting base plate BP is annular. That is, the overhang of the outer edge of the mounting base plate BP from the outer edge of the second stack member 22 is uniform over the circumferential direction of the mounting base plate BP. Thereby, when the support 10 moves near the outer edge of the first stack member 21, the load can be sufficiently dispersed to the mounting base plate BP regardless of the direction in which the support 10 moves relative to the first stack member 21.

[0061] Here, as described above, according to the sliding bearing 1 according to the present embodiment, the surface pressure applied to the structure B can be suppressed. At this time, depending on the surface pressure applied to the structure B via the sliding bearing 1, the load dispersion performance of the mounting base plate BP may become more than necessary. Therefore, the mounting base plate BP may be annular. By this, instead of suppressing the area where the mounting base plate BP contacts the second laminating member 22 of the sliding bearing 1 and suppressing the load dispersion performance, the volume of the mounting base plate BP can be reduced. Therefore, by suppressing the performance of the mounting base plate BP to the necessary level, the cost of the mounting base plate BP can be suppressed. Further, the second laminating member 22 is fastened to the mounting base plate BP by a second fastening member F2. Thereby, for example, when an earthquake occurs in the structure B provided with the sliding bearing 1, it is possible to suppress the displacement of the positions of the mounting base plate BP and the second laminating member 22.

[0062] Further, the second laminating member 22 includes a load transmission surface 22b that is in surface contact with the mounting base plate BP in a state of being installed on the structure B. Thereby, it is possible to more efficiently transmit the load transmitted from the support 10 to the mounting base plate BP. Further, the mounting base plate BP includes a first through hole BPH that penetrates in the vertical direction. The second laminating member 22 includes a second through hole 22d that penetrates in the vertical direction. And the first through hole BPH and the second through hole 22d communicate with each other. Thereby, the air remaining in the concrete placed below the mounting base plate BP can be moved from below the mounting base plate BP to above the second laminating member 22. Therefore, even when the concrete is placed after the mounting base plate BP and the second laminating member 22 are joined, it is possible to surely vent the air of the concrete placed below the mounting base plate BP. Also, by removing air from the concrete placed below the mounting base plate BP, it is possible to suppress the formation of cavities between the lower surface of the mounting base plate BP and the concrete. Therefore, the load can be more reliably transmitted from the mounting base plate BP to the concrete placed below the mounting base plate BP.

[0063] Also, the structure B includes a plurality of sliding bearings 1. Here, depending on the structure of the structure B, depending on the installation locations of the plurality of sliding bearings 1, there may be a difference in the magnitude of the load applied to each of the sliding bearings 1. Therefore, each of the plurality of mounting base plates BP corresponding to the plurality of sliding bearings 1 can simplify the configuration of the mounting base plate BP by making their shapes different in terms of thickness, area, etc. from each other, for example, at installation locations where the load applied to the sliding bearing 1 is sufficiently small, or at installation locations where the surface pressure of the load transmission surface 22b of the second stacking member 22 of the sliding bearing 1 described later is sufficiently small due to the load dispersion effect of the second stacking member 22. Alternatively, when the surface pressure of the load transmission surface 22b is sufficiently small and the lower structure B2 can directly receive the load from the load transmission surface 22b without causing a problem of insufficient concrete strength, the mounting base plate BP may not be provided.

[0064] Note that the technical scope of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, when the second stacking member 22 has a sufficient thickness and sufficient load dispersion is possible even when the support 10 moves relative to the first stacking member 21 in the horizontal direction, the edge 22E may not be provided on the second stacking member 22. Similarly, when sufficient load dispersion from the second stacking member 22 to the mounting base plate BP is possible, the edge BPE may not be provided on the mounting base plate BP.

[0065] Further, the mounting base plate BP may be provided between the upper structure B1 and the sliding bearing 1. In this case, the mounting base plate BP is preferably provided in the same manner as that provided between the lower structure B2 and the sliding bearing 1 described in the embodiment. Also, when the concrete forming the lower structure B2 is placed before the mounting base plate BP and the sliding bearing 1 are attached, the first through hole BPH and the second through hole 22d may not be provided. Further, if it is ensured that sufficient frictional force is provided in the horizontal direction and the position will not shift even during an earthquake, the first stack member 21, the second stack member 22, and the second stack member 22 and the mounting base plate BP may not be fixed by the first fastening member F1 or the second fastening member F2.

[0066] Also, in this embodiment, the sliding bearing 1 has been described as a double pendulum type spherical sliding bearing, but it is not limited thereto. For example, the sliding bearing 1 may be a so-called single pendulum type spherical sliding bearing. That is, the sliding bearing 1 may be a type in which the support 10 does not move in the horizontal direction, and only the upper stack 20U and the upper structure B1 can move in the horizontal direction by the sliding between the support 10 and the upper stack 20U. Also, the sliding bearing 1 may be a planar sliding bearing. Also, the sliding bearing 1 may be provided with a plurality of second stack members 22 stacked in the vertical direction. Also, the first stack member 21 may be composed of a plurality of members. Also, when viewed along the direction in which the first stack member 21 and the second stack member 22 are arranged, the first stack member and the second stack member may have the same size. Also, in this embodiment, the first stack member 21, the second stack member 22, and the mounting base plate BP are all exemplified as having a circular contour shape in plan view, but all or part of these may have a polygonal contour shape such as a rectangle in plan view. From the viewpoint of suppressing wasteful materials, the contour shapes in plan view of the first stack member 21, the second stack member 22, and the mounting base plate BP are preferably the same or similar. In addition, in the present embodiment, the first contact surface 21b of the first stack member 21 is exemplified as a flat surface, but the first contact surface may be a curved surface or a non-flat surface formed with irregularities or steps. In this case, the second contact surface of the second stack member has a shape corresponding to the first contact surface so as to be in surface contact with the first contact surface.

[0067] In addition, within the scope not departing from the gist of the present invention, it is possible to appropriately replace the components in the above-described embodiment with well-known components, and the above-described modification examples may be appropriately combined.

Explanation of Reference Numerals

[0068] 1 Sliding bearing 10 Support 10a Support-side sliding surface 20 Stack 20A Load distribution region 20L Lower stack 20U Upper stack 21 First stack member 21a Stack-side sliding surface 21b First contact surface 21S Screwed portion 22 Second stack member 22a Second contact surface 22b Load transmission surface 22c Positioning portion 22d Second through hole 22e First fastening hole 22E Edge portion 22e1 First diameter portion 22e2 Second diameter portion 22f Second fastening hole A Spreading angle B Structure B1 Upper structure B2 Lower structure BP Mounting base plate BPE Edge portion BPH First through hole BPS Screwed portion F1 First fastening member F2 Second fastening member F3 Third fastening member J Fixture

Claims

1. A sliding bearing attached to a mounting base plate provided in a structure, a shoe provided with a sliding surface on the shoe side, a support body provided with a support body side sliding surface that contacts the sliding surface on the shoe side, and transmits the load from the structure to the shoe, comprising: the shoe a plate-shaped first shoe member on which the sliding surface on the shoe side is formed, and a first contact surface is formed on the opposite side of the sliding surface on the shoe side; a plate-shaped second shoe member disposed on the opposite side of the support body in the first shoe member, and having a second contact surface that is in surface contact with the first contact surface; comprising: a sliding bearing characterized by the above.

2. The second shoe member has a load transmission surface that is in surface contact with the mounting base plate in a state where it is installed on the structure. The sliding bearing according to claim 1, characterized in that.

3. The sliding surface on the shoe side is a concave spherical surface, and the sliding surface on the support body side is a convex spherical surface. The sliding bearing according to claim 1, characterized in that.

4. The second shoe member has an edge portion that is located outside the outer edge of the first shoe member when viewed from the side where the first shoe member is located along the alignment direction, which is the direction in which the first shoe member and the second shoe member are aligned. The sliding bearing according to any one of claims 1 to 3, characterized in that.

5. When viewed from the alignment direction, the edge portion is annular. The sliding bearing according to claim 4, characterized in that.

6. A pair of the shoes are provided so as to sandwich the support body. The sliding bearing according to any one of claims 1 to 3, characterized in that.

7. The sliding bearing according to claim 6, further comprising a fixing jig for fixing the pair of provided shoes to each other. The sliding bearing according to claim 6, characterized in that.

8. The second shoe member is solid. The sliding bearing according to any one of claims 1 to 3, characterized in that.

9. The second shoe member has a load transmission surface that is in surface contact with the mounting base plate in a state where it is installed on the structure. The second shoe member has a through hole that penetrates across the load transmission surface and the second contact surface. The sliding bearing according to claim 8, characterized in that.

10. The thickness of the second shoe member is thicker than the thickness of the first shoe member. The sliding bearing according to any one of claims 1 to 3, characterized in that.

11. The first shoe member and the second shoe member are joined by a fastening member. The sliding bearing according to any one of claims 1 to 3, characterized in that.

12. The second laminated member includes a load transmission surface that is in surface contact with the mounting base plate in a state where the second laminated member is installed on the structure. The first laminated member and the second laminated member are joined by a fastening member. The fastening member is inserted into a fastening hole formed in the second laminated member so as to be recessed from the load transmission surface toward the second contact surface, protrudes from the second contact surface, and is disposed in a state where the protruding portion is located inside the first laminated member. The sliding bearing according to any one of claims 1 to 3, characterized in that.

13. The second laminated member includes a positioning portion that horizontally positions the first laminated member with respect to the second laminated member. The sliding bearing according to any one of claims 1 to 3, characterized in that.

14. The positioning portion is a recess formed in the second laminated member in a shape corresponding to the contour shape of the first contact surface. The sliding bearing according to claim 13, characterized in that.

15. The positioning portion is a protruding portion that protrudes from the second contact surface. The sliding bearing according to claim 13, characterized in that.

16. Comprising the sliding bearing according to claim 1. The structure characterized by that.

17. The mounting base plate includes an edge portion that is located outside the outer edge of the second laminated member when viewed from the side where the second laminated member is located along the direction in which the second laminated member and the mounting base plate are arranged. The structure according to claim 16, characterized in that.

18. The thickness of the second laminated member is greater than the thickness of the mounting base plate. The structure according to claim 16, characterized in that.

19. The edge portion is annular. The structure according to claim 17, characterized in that.

20. The mounting base plate is annular. The structure according to any one of claims 16 to 19, characterized in that.

21. The second laminated member includes a load transmission surface that is in surface contact with the mounting base plate in a state where the second laminated member is installed on the structure. The mounting base plate includes a first through hole that penetrates in the vertical direction. The second laminated member includes a second through hole that penetrates in the vertical direction. The first through hole and the second through hole communicate with each other. The structure according to any one of claims 16 to 19, characterized in that.

22. A plurality of the sliding bearings are provided. A plurality of mounting base plates are provided corresponding to each of the plurality of sliding bearings. Some of the mounting base plates among the plurality of mounting base plates have a different shape from other mounting base plates. The structure according to claim 16, characterized in that.

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