JP4463955B2 - Stress transmission device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a stress transmission device that is installed between a pile head of a foundation pile and an upper structure and transmits stress between the upper structure and the foundation pile.
[0002]
[Prior art]
Conventionally, when a building is constructed, it is generally performed to support the upper structure on a pile embedded up to the supporting ground, thereby supporting the entire upper structure.
Conventionally, it was supposed that the pile head was rigidly connected to the superstructure, but in this case, there is a concern that the pile head may be destroyed when receiving a horizontal force on the pile head during an earthquake, in order to prevent this Reinforcement such as greatly expanding the pile head was necessary.
[0003]
Therefore, in order to reduce the stress generated in the pile head, the pile head is connected to the upper structure so that it can rotate relative to the upper structure, and the pile head is released to release the stress on the pile head. A roller coupling structure has been proposed that can move and release the stress of the pile head (for example, JP-A-1-284613, JP-A-8-120687, JP-A-10-227039, JP-A-10-227040).
[0004]
[Problems to be solved by the invention]
However, in these structures, it was necessary to reduce the friction between the pile head and the upper structure in order to cause a good relative displacement between the pile head and the upper structure. For this purpose, in order to make the contact surface between the pile head and the upper structure smooth, it is necessary to perform resin processing or machining, which causes an increase in cost.
Further, in these structures, there is a concern that shear force cannot be reliably transmitted in some cases when an attempt is made to allow relative displacement between the pile head and the upper structure.
[0005]
The present invention has been made in view of such circumstances, and prevents transmission of a bending moment between the pile head and the upper structure without increasing the cost, and in this case, the pile head and It is an object of the present invention to provide a stress transmission device that can satisfactorily cope with a shearing force acting between the upper structure and the upper structure.
[0006]
[Means for Solving the Problems]
In order to solve the above problems, the present invention employs the following means.
That is, the stress transmission device according to claim 1 is a structure in which the pile head member installed at the pile head of the foundation pile and the upper structure supported by the foundation pile are fixed and opposed to the pile head member. An object support member,
The outer periphery of the upper surface of the pile head member and the outer peripheral edge of the lower surface of the structure support member are in contact with each other up and down via a contact surface forming a part of a virtual spherical surface,
The contact surface is formed in an annular shape having a vertical axis passing through the center of curvature of the phantom spherical surface as a central axis.
[0007]
When such a configuration is adopted, the pile head member and the structure support member are separated from the structure support member by a pile compared to the case where the predetermined range near the vertical axis is in contact with the virtual spherical surface as a contact surface. Of the axial force acting on the head member, the normal direction component of the contact surface can be reduced, thereby reducing the frictional resistance of the contact surface. Moreover, it can reduce similarly about the component which is going to produce a side slip among the horizontal forces which act between a pile head member and a structure support member.
[0008]
Further, in the stress transmission device according to claim 1, the contact surface includes a convex surface formed on one of the pile head member and the structure support member, and a concave surface formed on the other side. Formed as a contact surface, the curvature of the concave surface is larger than the curvature of the convex surface,
At least one of the convex surface and the concave surface is formed from a central portion and an outer ring portion centered on the vertical axis, the outer ring portion constitutes the same plane as the phantom spherical surface, and the central portion is the It is characterized by being formed in a concave shape on the basis of a virtual spherical surface.
[0009]
With such a configuration, one of the convex surface and the concave surface has its center portion not in contact with the other, and only the outer ring portion is in contact with the other.
Furthermore, the stress transmission device according to claim 1 is characterized in that the outer peripheral edge of the convex surface is formed as a curved surface having a smaller radius of curvature in the vertical cross section than the phantom spherical surface.
With such a configuration, it is possible to reduce the friction at the outer peripheral edge of the concave surface, and to prevent the concave surface and the convex surface from being rotationally displaced using this portion as a fulcrum.
[0010]
The stress transmission device according to claim 2 is the stress transmission device according to claim 1 ,
The center portion is formed as a hole in the convex surface or the concave surface.
[0011]
With such a configuration, the central portion can be easily formed in a concave shape.
[0012]
Stress transmission apparatus according to the third aspect, a stress transmission apparatus according to claim 1 or 2,
The central portion is a horizontal plane formed in the convex surface.
[0013]
With such a configuration, the central portion can be formed in a concave shape with reference to the virtual spherical surface by simple processing.
[0016]
The stress transmission device according to claim 4 is the stress transmission device according to any one of claims 1 to 3 ,
One of the convex surface and the concave surface is characterized in that minute irregularities are formed on the surface, and the other surface is formed more smoothly than the one surface.
[0017]
The stress transmission device according to claim 5 is the stress transmission device according to any one of claims 1 to 4 ,
Both the convex surface and the concave surface are configured to have a plurality of grooves arranged in parallel to each other at a predetermined interval on the surface,
The width dimension of the groove portion formed on one of the convex surface and the concave surface is smaller than the distance dimension between the groove portions formed on the other surface, and is formed on the other surface. The width dimension of the groove is characterized by being smaller than the distance dimension between the grooves formed on the one side.
[0018]
With such a configuration, the contact area between the convex surface and the concave surface can be further reduced.
[0032]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 4 is a diagram schematically showing an embodiment of the present invention. In the figure, reference numeral 1 indicates a building (structure). This building 1 is composed of a foundation pile 2 installed on the ground G and an upper structure 3 supported by the foundation pile 2, in order to transmit stress between the foundation pile 2 and the upper structure 3. The stress transmission device 4 is provided.
[0033]
FIG. 1 is an enlarged view of the stress transmission device 4. As shown in the figure, the stress transmission device 4 includes a pile head member 5 installed on a pile head 2 a of the foundation pile 2, and a structure support fixed to the upper structure 3 and disposed opposite to the pile head member 5. The structure has a member 6.
[0034]
Then, in the stress transmission device 4, lower outer peripheral portion of the upper surface outer peripheral portion and the structure supporting member 6 of the pile head member 5 is in contact with each other up and down through the abutment surface 8 forming a part of a virtual spherical surface Sv configuration It has become. FIG. 2 is an enlarged view showing the vicinity of the contact surface 8. The contact surface 8 is formed as a contact surface between the convex surface 9 formed on the pile head member 5 and the concave surface 10 formed on the structure support member 6. Both the convex surface 9 and the concave surface 10 are formed so as to constitute the same surface as the virtual spherical surface Sv, and are symmetrical about the vertical axis Va passing through the center of curvature Cs (see FIG. 1) of the virtual spherical surface Sv. It has become. Accordingly, the contact surface 8 is configured as an axially symmetric annular curved surface with the vertical axis Va as a rotation axis.
Although not clearly shown in FIG. 2, the radius of curvature of the concave surface 10 is slightly larger than that of the convex surface 9 as will be described later (see paragraph 0057).
[0035]
Furthermore, the concave surface 10 is formed of a central portion 11 centering on the vertical axis Va and an outer ring portion 12 positioned outside thereof. The central portion 11 of the concave surface 10 is formed as a hole portion 13, and thus has a configuration formed in a concave shape when the phantom spherical surface Sv is used as a reference. Therefore, in the concave surface 10, only the outer ring portion 12 forms the contact surface 8 that contacts the concave surface 9.
[0036]
FIG. 3 is an enlarged view showing the outer peripheral edge portion 14 of the convex surface 9. As shown in the drawing, the outer peripheral edge portion 14 of the convex surface 9 is formed as a curved surface having a smaller radius of curvature (r1 in the drawing) in the vertical cross section than the radius of curvature of the phantom spherical surface Sv.
[0037]
FIG. 5 is an enlarged view of the contact portion between the convex surface 9 and the concave surface 10. By forming the convex surface 9 as an as-cast, minute irregularities 16 are formed on the surface thereof as shown in the figure. Further, the unevenness 16 is uniformly formed in the direction intersecting the paper surface in the drawing. On the other hand, the concave surface 10 has a surface that is smoother than the convex surface 9. This is further enlarged and shown in FIG. 6, and as shown in the figure, regular irregularities 16 are formed on the convex surface 9, so that both the concave surface 10 and the convex surface 9 are formed smoothly. The contact area between the concave surface 10 and the convex surface 9 is reduced as compared with the case (as shown in FIG. 7).
[0038]
In the building 1 and the stress transmission device 4 having such a configuration, the pile head member 5 and the structure support member 6 are in contact with each other only at the outer ring portion 12 of the concave surface 10. As a result, the pile head member 5 and the structure support member 6 are in contact with the entire surface around the vertical axis Va in the virtual spherical surface Sv (as shown in FIG. 9). The frictional resistance can be reduced.
[0039]
That is, as shown in FIG. 9, when the hole 13 is not formed on the concave surface 10 ′ or the convex surface 9 ′, the axial force q transmitted from the upper structure when the bending moment M acts is relatively high on the convex surface 9. It will be supported over a wide range from the top 9a 'which is almost flat to the outer edge 9b'. In this case, the normal direction component of the axial force q acting on the contact surfaces of the convex surface 9 ′ and the concave surface 10 ′ is q · cos θ when the angle of the concave surface from the horizontal plane is θ, as shown in FIG. Therefore, the friction between the convex surface 9 ′ and the concave surface 10 ′ that becomes resistance when the structure support member 6 slides along the pile head member 5 can be expressed as μq · cos θ (μ is the friction on the contact surface). Represents the coefficient.) Further, in the vicinity of the apex portion 9a ′ of the convex surface 9 ′, θ is small, so that the friction between the convex surface 9 ′ and the concave surface 10 ′ is approximately μq.
[0040]
On the other hand, in the stress transmission device 4 of the present embodiment having the configuration shown in FIG. 8, the axial force q is supported by the outer ring portion 17 of the convex surface 9 where the gradient θ is steep. Therefore, in this case, when cos θ is small and the same axial force q is applied, the frictional resistance is smaller than in the case of FIG. 9, and as a result, between the basic convex surface 9 and the concave surface 10 with a small bending moment. It is possible to cause rotation.
[0041]
In addition, in the structure shown in FIG. 8, the component q · sin θ that causes rotation of the axial force q is larger than that in the case shown in FIG. 9. The bending moment required for relative displacement can be kept small.
[0042]
Accordingly, the bending moment M required when the pile head member 5 and the structure support member 6 are relatively displaced along the phantom spherical surface Sv can be reduced, whereby transmission between the foundation pile 2 and the upper structure 3 can be achieved. The bending moment that is generated can be suppressed, the deformation performance of the building 1 as a whole can be secured, and the building 1 can be made even safer.
[0043]
Further, in this stress transmission device 4, since stress is transmitted only at the outer ring portion 12 of the concave surface 10, the side slip between the pile head member 5 and the structure support member 6 among the acting axial force. It is possible to increase the component that resists the movement, and it is possible to reduce the component that causes the skid among the horizontal force that acts between the pile head member 5 and the structure support member 6.
[0044]
That is, as shown in FIG. 11, compared to the case where the axial force is transmitted from the concave surface 10 ′ in the vicinity of the top portion 9a ′ of the convex surface 9 ′ (for example, the range indicated by 9c ′ in the figure), When the hole 13 is provided in the concave surface 10 as shown in FIG. 10, the gradient θ of the contact surface becomes larger than that in the case of FIG. While h · cos θ decreases, the component q · tan θ of the axial force q that resists skid increases. Thereby, the shear force which can be transmitted between the pile head member 5 and the structure support member 6 can be increased.
[0045]
At this time, in particular, as shown in FIG. 12, when the radius of curvature of the concave surface 10 ″ is larger than that of the convex surface 9 ″ and the hole 13 as shown in FIG. Since the concave surface 10 ″ is in contact with only the narrow range of the central portions 9a ″ and 10a ″, the shearing force that can be transmitted between the convex surface 9 ″ and the concave surface 10 ″ becomes very small, and FIG. As shown, there is a concern that the pile head member 5 ″ and the structure support member 6 ″ may skid and come off, but the hole 13 is provided by adopting the structure shown in FIG. Thus, even if the radius of curvature of the concave surface 10 is slightly larger than that of the convex surface 9, the outer ring portion 12 of the concave surface 10 (the outer ring portion 17 of the convex surface 9) has a circumferential shape between the pile head member 5 and the structure support member 6. Can be brought into contact with the pile head member 5 and the structure support. To increase the shear forces can be transmitted between the wood 6, it is possible to ensure the safety of the entire building.
[0046]
Further, when the curvatures of the convex surface 9 ″ and the concave surface 10 ″ do not coincide with each other and the hole 13 as shown in FIG. 10 is not provided, as shown in FIG. Sometimes, the structure support member 6 ″ is easy to rotate, and therefore the structure support member 6 ″ may be inclined and installed. However, in the configuration as shown in FIG. The pile head member 5 and the structure support member 6 are brought into circumferential contact with each other at the portion 12 (the outer ring portion 17 of the convex surface 9), and the structure support member 6 is stably placed on the pile head member 5. Therefore, the stability during construction is good and construction accuracy can be ensured.
[0047]
As described above, in the above-described stress transmission device 4, the convex surface 9 is formed from the center portion 11 and the outer ring portion 12, and the outer ring portion 12 forms the same plane as the phantom spherical surface Sv. Is formed in a concave shape with respect to the phantom spherical surface Sv, only the outer ring portion 12 comes into contact with the concave surface 10, whereby the pile head member 5 and the structure support member 6 can be easily formed. An effect as described above can be obtained by realizing a configuration in contact with the ring.
[0048]
Further, in this case, since the central portion 11 is formed as the hole portion 13, the central portion 11 can be easily formed in a concave shape with respect to the virtual spherical surface Sv, whereby the pile head member 5 can be formed by simple processing. In addition, the structure support member 6 can be brought into contact with the ring.
[0049]
Moreover, in the stress transmission device 4 described above, the outer peripheral edge portion 14 of the convex surface 9 is formed as a curved surface in which the radius of curvature r1 in the vertical section is smaller than the radius of curvature of the phantom spherical surface Sv. The friction which arises in the outer periphery part 14 of this can be reduced.
[0050]
That is, as shown in FIG. 15, in the configuration in which the outer peripheral edge portion 14 ′ is not formed as a curved surface, when the bending moment M acts between the structure support member 6 and the pile head member 5, It is conceivable that friction is likely to occur at the peripheral portion 14 ′, and the structure support member 6 is lifted with this portion as a fulcrum, and then a behavior occurs such that slipping occurs only after the friction is broken. However, in the present embodiment, by processing the outer peripheral edge portion 14 as a curved surface, it is possible to cause slippage between the two smoothly.
[0051]
FIG. 16 schematically shows the relationship between the rotation angle θ of the pile head member 5 and the structure support member 6 in this case and the bending moment M transmitted between them. As shown in FIG. 16, when the outer peripheral edge portion 14 of the convex surface 9 is not processed as a curved surface (indicated by a broken line in the figure), as the rotation angle θ increases from 0, the pile head member 5 and the structure When the bending moment M acting between the object supporting member 6 temporarily rises and then becomes a constant value Mc, but the outer peripheral edge 14 of the convex surface 9 is a curved surface (in the case indicated by a solid line in the figure). In such a case, such a behavior does not occur, and as the rotation angle θ increases, the bending moment M gradually behaves so as to approach the constant value Mc. Therefore, an increase in the bending moment M required when the structure support member 6 and the pile head member 5 are rotationally displaced can be suppressed, and the rotational deformation performance in the stress transmission device 4 can be improved.
[0052]
Further, in the above-described stress transmission device 4, since the minute irregularities 16 are formed on the surface of the convex surface 9 and the concave surface 10 is formed smoothly, the contact area between them can be reduced. As a result, the frictional force acting between the two can be reduced. Therefore, the bending moment M required when the pile head member 5 and the structure support member 6 are rotationally displaced can be further reduced, and the rotational deformation performance of the stress transmission device 4 can be improved.
[0053]
In the above embodiment, other configurations may be adopted without departing from the spirit of the present invention.
For example, in the above-described embodiment, the hole portion 13 is provided only on the concave surface 10. However, the present invention is not limited to this, and the hole portion 13 is provided on the convex surface 9 or both the concave surface 10 and the convex surface 9. It may be.
[0054]
Moreover, in the said embodiment, it was the structure by which the micro unevenness | corrugation 16 was provided only in the convex surface 9, but it is not restricted to this, The micro unevenness | corrugation 16 is provided in the concave surface 10, and the convex surface 9 is formed smoothly. It may be.
[0055]
Further, the shapes of the pile head member 5 and the structure support member 6 are not limited to those shown in the above embodiment, and a hole is provided in the concave surface 10 of the structure support member 6 as shown in FIG. Instead, this may be formed as the same spherical surface, and the center portion of the convex surface 9 of the pile head member 5 may be formed as the horizontal surface 19. Thereby, the center part of the convex surface 9 can be formed in a concave shape with reference to the virtual spherical surface Sv only by simple processing, and the configuration in which only the outer ring portion 17 of the convex surface 9 is in contact with the concave surface 10 is realized. The same effect as the above embodiment can be obtained.
[0056]
Moreover, in the said embodiment or the modification shown in FIG. 17, although the convex surface 9 was formed in the pile head member 5, and the concave surface 10 was formed in the structure support member 6, it is not restricted to this, Pile A concave surface may be formed on the head member 5, and a convex surface may be formed on the structure support member 6, and these may be brought into contact with each other.
[0057]
In the present invention, the radius of curvature of the concave surface 10 is slightly larger than that of the convex surface 9 as described above.
[0058]
Further, the curvature of the convex surface 9 and the concave surface 10 or the diameter of the hole 13 is the same as that of the above embodiment as long as the radius of curvature of the concave surface 10 is slightly larger than that of the convex surface 9 as described above. It is not limited to this, and an appropriate one can be determined in consideration of the axial force and the horizontal force acting on the pile head 2a.
[0059]
Furthermore, the configuration of the contact portion between the convex surface 9 and the concave surface 10 in the above embodiment may be as shown in FIG. In FIG. 18, the convex surface 9 and the concave surface 10 are configured to have uniform groove portions 21 and 21 ′ in the direction intersecting with the paper surface, respectively. Here, the groove portion 21 formed on the convex surface 9 has a distance dimension between the groove portions 21 ′ and 21 ′ formed on the concave surface 10 in contact with the convex surface 9 (that is, positioned between the groove portions 21 ′ and 21 ′). The groove portion 21 ′ formed on the concave surface 10 is formed between the groove portions 21, 21 formed on the convex surface 9 in contact with the concave surface 10. 21 is formed to be smaller than the distance dimension L2 (that is, the width dimension of the convex part 22 positioned between the groove parts 21 and 21) L2. With such a configuration, when the convex surface 9 and the concave surface 10 come into contact with each other, no matter how the convex surface 9 and the concave surface 10 are relatively displaced, the groove portion 21 and the concave portion 22 ', and the groove portion 21' and the convex portion 22 And the contact area between the convex surface 9 and the concave surface 10 can be reduced as compared with the case where both the convex surface 9 and the concave surface 10 are formed smoothly. Thereby, the frictional force between the convex surface 9 and the concave surface 10 can be reduced, and the rotational deformation performance in the stress transmission device 4 can be improved.
[0060]
Moreover, in the said embodiment, although the stress transmission apparatus 4 was applied to the building 1, it is not limited to this, All structures of the form which have foundation piles and superstructures, such as a civil engineering structure In addition, the stress transmission device 4 can be applied.
[0061]
In addition, other configurations may be adopted without departing from the spirit of the present invention, and the above-described modified examples may be appropriately combined. Nor.
[0062]
【The invention's effect】
As described above, in the invention according to claim 1 , both the pile head member and the structure support member are in contact with each other over the entire surface around the vertical axis in the phantom spherical surface. The component in the normal direction of the contact surface can be reduced in the axial force acting on the contact force, and the frictional resistance can be reduced. Therefore, the pile head of the foundation pile and the upper structure can be rotated with a small bending moment, and the deformation performance of the entire structure can be ensured to make the structure safe.
Furthermore, in this case, among the axial forces acting between the foundation pile and the superstructure, the component that resists the side slip between the pile head member and the structure support member is increased, and the foundation pile and the superstructure The horizontal force acting between the pile head member and the structure support member can be increased by increasing the shear force that can be transmitted between the pile head member and the structure support member. Sex can be secured.
Moreover, since a structure support member is stably mounted on a pile head member, stability during construction is good and construction accuracy can be ensured.
[0063]
In addition, since only one outer ring portion of the convex surface and the concave surface is in contact with the other, it is possible to easily realize a configuration in which the pile head member and the structure support member are in annular contact .
Furthermore, since the outer peripheral edge of the convex surface is formed as a curved surface having a smaller radius of curvature than the virtual spherical surface, the friction of the outer peripheral edge of the convex surface can be reduced, and the pile head member and the structure support member Slip is generated smoothly between them, and the increase in bending moment required when these are rotationally displaced is suppressed, ensuring the rotational performance of the pile head member and the structure support member (foundation pile and superstructure). Can do.
[0064]
In the invention which concerns on Claim 2 , since the center part of a convex surface or a concave surface is formed as a hole part, a center part can be easily formed into a concave shape on the basis of a virtual spherical surface, and a pile head member by simple processing And the structure support member can be brought into annular contact.
[0065]
In the invention according to claim 3 , the center portion of the convex surface can be formed in a concave shape with reference to the virtual spherical surface by simple processing, and a configuration in which the convex surface is in contact with the concave surface in an annular shape can be easily realized. .
[0067]
In the invention according to claim 4 , since the minute irregularities are formed on the surface of either the convex surface or the concave surface, and the other is formed smoothly, the contact area between them can be reduced, Thereby, the frictional force acting between the two can be reduced. Therefore, it is possible to reduce the bending moment required when the pile head member and the structure support member are rotationally displaced, and to ensure rotational performance.
[0068]
In the invention according to claim 5 , since the width dimension of the groove portion formed on the convex surface and the concave surface is smaller than the distance dimension between the groove portions on the surface to be contacted, the fitting between the convex surface and the concave surface is avoided. However, the contact area can be reduced, and thereby the frictional force acting between the two can be reduced. Therefore, it is possible to reduce the bending moment required when the pile head member and the structure support member are rotationally displaced, and to ensure rotational performance.
[Brief description of the drawings]
FIG. 1 is an elevational sectional view of a stress transmission device schematically showing an embodiment of the present invention.
FIG. 2 is an enlarged sectional view of the vicinity of a contact surface between a pile head member and a structure support member in FIG.
FIG. 3 is an enlarged sectional view showing an outer peripheral edge portion of a convex surface of a pile head member in FIG.
4 is an elevational sectional view showing the overall structure of a structure to which the stress transmission device shown in FIG. 1 is applied. FIG.
FIG. 5 is an enlarged cross-sectional view illustrating the contact surface between the pile head member and the structure support member illustrated in FIG. 2 in a further enlarged manner.
6 is an enlarged vertical sectional view of a main part of FIG. 5;
FIG. 7 is an elevational sectional view of these contact surfaces when both the concave surface of the pile head member and the convex surface of the structure support member are formed smoothly.
FIG. 8 is an elevational sectional view for explaining a frictional force acting on the contact surface shown in FIG. 2;
FIG. 9 is an elevational sectional view for explaining the frictional force acting on the contact surface when it is assumed that no hole is provided in the concave surface of the structure support member in FIG.
10 is an elevational sectional view for explaining a force resisting a horizontal force acting between a pile head member and a structure support member on the contact surface shown in FIG. 2; FIG.
FIG. 11 resists the horizontal force acting between the pile head member and the structure support member at the contact surface when it is assumed that no hole is provided in the concave surface of the structure support member in FIG. It is an elevation sectional view for explaining force.
12 is an elevational sectional view of a pile head member and a structure support member showing a situation where the curvature of the concave surface does not coincide with the convex surface in the configuration shown in FIGS. 9 and 11. FIG. .
13 is an elevational sectional view showing a situation when a side slip occurs between a pile head member and a structure support member in the configuration shown in FIG.
14 is an elevational sectional view showing a situation when the structure support member is installed with an inclination in the configuration shown in FIG.
FIG. 15 shows the structure supporting member when the outer peripheral edge of the convex surface of the pile head member is not processed into a curved surface at the contact surface between the pile head member and the structure supporting member shown in FIG. It is an elevational sectional view for showing behavior expected to occur.
FIG. 16 is transmitted between the rotation angle (horizontal axis) of the pile head member and the structure support member between the case where the outer peripheral edge of the convex surface of the pile head member is processed into a curved surface and the case where it is not formed. It is a graph for comparing the relationship with a bending moment (vertical axis).
FIG. 17 is an elevational sectional view of a stress transmission device schematically showing another embodiment of the present invention.
FIG. 18 is an enlarged vertical sectional view of a contact surface between a concave surface and a convex surface schematically showing another embodiment of the present invention.
[Explanation of symbols]
1 Building (structure)
2 Foundation pile 3 Superstructure 4 Stress transmission device 5 Pile head member 6 Structure support member 8 Contact surface 9 Convex surface 10 Concave surface 11 Center portion 12 Outer ring portion 13 Hole portion 14 Outer peripheral edge portion 16 Concavity and convexity 19 Horizontal planes 21, 21 ′ Groove portion Sv Virtual spherical surface Va Vertical axis

Claims (5)

A pile head member installed at the pile head of the foundation pile, and a structure support member fixed to the upper structure supported by the foundation pile and disposed opposite to the pile head member,
The outer periphery of the upper surface of the pile head member and the outer peripheral edge of the lower surface of the structure support member are in contact with each other up and down via a contact surface forming a part of a virtual spherical surface,
The contact surface is formed in an annular shape with a vertical axis passing through the center of curvature of the phantom spherical surface as a central axis ,
The contact surface is formed as a contact surface between a convex surface formed on one of the pile head member and the structure support member and a concave surface formed on the other, and the concave surface The curvature is greater than the curvature of the convex surface,
At least one of the convex surface and the concave surface is formed from a central portion and an outer ring portion centered on the vertical axis, the outer ring portion constitutes the same plane as the phantom spherical surface, and the central portion is the It is formed in a concave shape based on the virtual spherical surface ,
The stress transmission device according to claim 1, wherein the outer peripheral edge of the convex surface is formed as a curved surface having a smaller radius of curvature in a vertical cross section than the phantom spherical surface. The stress transmission device according to claim 1 ,
The stress transmission device, wherein the central portion is formed as a hole in the convex surface or the concave surface. The stress transmission device according to claim 1 or 2 ,
The stress transmission device, wherein the central portion is a horizontal plane formed in the convex surface. The stress transmission device according to any one of claims 1 to 3 ,
One of the convex surface and the concave surface has minute irregularities formed on the surface thereof, and the other is formed more smoothly than the one surface. The stress transmission device according to any one of claims 1 to 4 ,
Both the convex surface and the concave surface are configured to have a plurality of grooves arranged in parallel to each other at a predetermined interval on the surface,
The width dimension of the groove portion formed on one of the convex surface and the concave surface is smaller than the distance dimension between the groove portions formed on the other surface, and is formed on the other surface. The stress transmission device according to claim 1, wherein a width dimension of the groove portion is smaller than a distance dimension between the groove portions formed on the one side.

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