JP2019007338A - Pipe structure mounting structure and pipe structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent stress concentration and reduce the influence of environmental conditions in a pipe structure in which a pipe member having a tapered pipe expansion portion formed at an end thereof is used. SOLUTION: The mounting structure of a pipe structure includes a tapered pipe expansion portion formed in a section having a predetermined length including at least one end portion, and a straight portion formed in a section other than the section having a predetermined length. It includes a tube member including a main body portion, and a pedestal including a tubular projecting portion that protrudes from the main body portion and is press-fitted to the inner peripheral surface side of the tube expansion portion. The outer peripheral surface of the tubular protrusion has a tapered shape corresponding to the inner peripheral surface of the tube expansion portion, and the outer diameter of the tubular protrusion is the first outer diameter larger than the inner diameter of the end opening of the tube expansion portion due to the tapered shape of the outer peripheral surface. It varies from diameter to a second outer diameter that is smaller than the inner diameter of the end opening. [Selection diagram] Fig. 1

Description

  The present invention relates to a pipe structure mounting structure and a pipe structure, and more particularly to a pipe structure mounting structure and a pipe structure using a pipe member having a tapered pipe-shaped portion formed at an end.

  In Patent Document 1, a first steel pipe having a tapered pipe expansion portion at an end portion, and a second steel pipe having a tapered pipe contraction portion at an end portion and having a strength higher than that of the first steel pipe, A steel pipe column structure is described in which a contracted tube portion is joined by fitting and an axial force exceeding the weight of the first steel pipe is introduced. Here, due to the tapered shape, the diameter of the steel pipe gradually increases toward the end side in the above-described expanded pipe part, and the diameter of the steel pipe gradually decreases toward the end side in the contracted pipe part. According to Patent Document 1, in the steel pipe column structure as described above, the yield strength of the column base can be efficiently improved, and a variable section column can be configured.

  In FIG. 1 and the like of the above Patent Document 1, the second steel pipe that constitutes the column base is embedded in the ground. Such a structure of the column base is used in the case of a steel pipe column that supports a heavy object such as a building. On the other hand, when supporting a lighter structure, a basic structure in which the lower end of a steel pipe column is joined to a base plate fixed on the ground or a floor surface is generally used. However, such a basic structure is not described in Patent Document 1.

  Here, in FIG. 9 and the like of Patent Document 2, the lower end of the steel pipe column is welded to the base plate as a conventional basic structure for a normal steel pipe column in which a tapered pipe expansion portion is not formed at the end, and the upper surface of the base plate And a structure in which vertical ribs for reinforcement are welded to the lower side surface of the steel pipe column. Patent Document 2 describes that in such a basic structure, stress concentration occurs in the welded portion between the steel pipe column and the vertical rib.

  In FIG. 1 of Patent Document 2, the base plate is joined to the bottom of a hollow tube having a diameter larger than the outer diameter of the lower end of a normal steel tube column, and the lower end of the steel tube column is inserted inside the hollow tube. A technique has been proposed in which these are combined and integrated by filling an electrically insulating amorphous hardener between the inner surface of the empty tube and the outer surface of the steel tube column. Thereby, since the welded portion between the steel pipe column and the other member is not formed in the foundation structure, stress concentration on the welded portion can be prevented.

Japanese Patent Laying-Open No. 2015-74924 Japanese Patent No. 3464416

  By the way, in the column structure including the steel pipe column, since the cross-sectional force acting on the column base portion on the lower end side is large, it is preferable that the column base portion has a high proof stress cross section compared to the column upper side. However, in the case of Patent Document 1, an efficient joint is provided to enable variable cross-section injection. However, when a base plate is used, a stress concentration point is generated at the joint between the column base and the base plate, and repeated. There is a concern that fatigue cracks may occur from the stress concentration location due to the load. In addition, even if the cross section of the column base has high yield strength, that is, high fatigue durability, if the joint with the base plate has low fatigue durability, the durability of the entire column structure remains low. is there.

  On the other hand, although the solution of this problem is proposed in Patent Document 2, the joint portion with the steel pipe column filled with the irregular hardener is exposed to the outside at the upper end of the hollow pipe. Therefore, rainwater tends to accumulate due to its structure. If the accumulated rainwater enters the gap between the members forming the joint, the durability of the entire column structure may be impaired due to corrosion of the members. That is, the technique described in Patent Document 2 is easily affected by environmental conditions such as rainwater.

  Therefore, the present invention is a novel and capable of preventing stress concentration and reducing the influence of environmental conditions in a pipe structure in which a pipe member having a tapered pipe-shaped portion formed at the end is used. It is an object of the present invention to provide an improved pipe structure mounting structure and pipe structure.

An attachment structure for a pipe structure according to an aspect of the present invention includes a tapered pipe expansion portion formed in a section having a predetermined length including at least one end, and a straight formed in a section other than the section having a predetermined length. A tube member including a portion, a main body portion, and a pedestal including a tubular projecting portion that protrudes from the main body portion and is press-fitted into the inner peripheral surface side of the expanded pipe portion. The outer peripheral surface of the tubular projecting portion has a taper shape corresponding to the inner peripheral surface of the tube expanding portion, and the outer diameter of the tubular projecting portion is larger than the inner diameter of the end opening of the expanded tube portion due to the taper shape of the outer peripheral surface. The diameter changes from the diameter to a second outer diameter that is smaller than the inner diameter of the end opening.
By press-fitting the tubular projecting portion having the shape as described above to the inner peripheral surface side of the expanded portion, the pedestal and the tube member can be securely supported and joined together. In the support joint, no weld is formed between the pipe member and the other member, so that stress concentration on the weld does not occur. Moreover, since the junction part of a pipe expansion part and a tubular protrusion part is a structure where rain water does not accumulate easily, the influence of environmental conditions, such as rain water, can be reduced.

In the above mounting structure, the main body portion and the tubular projecting portion of the pedestal may be formed continuously.
For example, when the main body portion of the pedestal and the tubular projecting portion are continuously formed by casting or the like, since no welded portion is formed between each portion of the pedestal, stress concentration on the welded portion does not occur.

In the mounting structure described above, the wall thickness of the tubular projecting portion may become thinner toward the end opposite to the main body portion.
By changing the thickness of the tubular projecting portion as described above, the weight of the pedestal can be reduced while reducing the stress acting on the connection portion between the tubular projecting portion and the main body portion.

The attachment structure may further include an electrical component attached to the inner peripheral surface of the tubular protrusion.
By attaching an electrical component to the inner peripheral surface of the tubular projecting portion before joining the tube member and the pedestal, there is no need to form an opening in the peripheral surface of the tube member, and stress concentration in the opening is prevented. be able to.

In the mounting structure described above, the tubular projecting portion may include a beveled surface formed following the outer peripheral surface at the end opposite to the main body portion. Further, in this case, the tubular protrusion may have a groove connected to the oblique surface and extending in the longitudinal direction of the tubular protrusion along the outer peripheral surface.
As a result, the beveled surface tends to guide the water droplets that have traveled along the inner peripheral surface of the tapered tube to the outer peripheral surface side of the tubular projecting portion, thereby preventing the inflow to the inner peripheral surface side as much as possible. Can do. Further, when the groove is provided, the water droplets accumulated on the oblique surface can be discharged to the outside of the tapered tube, so that the influence of the water droplets on the pedestal and the electric parts can be reduced.

In the above mounting structure, the main body may be a base plate.
The base plate is attached to the foundation or the ground, for example. In this case, the attachment structure functions as the basic structure of the pipe structure.

The mounting structure further includes a tube member including a tapered tube-shaped contraction portion formed at at least one end, and the pedestal further includes a cavity formed in the main body portion into which the tube contraction portion is press-fitted, The inner peripheral surface has a tapered shape corresponding to the contracted tube portion, and the inner diameter of the cavity is increased from the first inner diameter larger than the outer diameter of the end portion of the contracted tube portion due to the tapered shape of the inner peripheral surface of the cavity. The second inner diameter may be smaller than the outer diameter of the end of the contraction tube.
For example, the attachment structure may function as a connection structure that connects two or more pipe members to each other. In this case, one pipe member is pressure-bonded by press-fitting a tubular protrusion into the expanded portion, whereas the other pipe member is pressure-bonded and bonded by press-fitting the contracted tube portion into the cavity. Also good.

The mounting structure further includes an additional pipe member including a tapered pipe expanding portion formed at at least one end, and the base protrudes from the main body portion and is additionally press-fitted into the pipe expanding portion of the additional pipe member. The tubular protrusion may be further included.
When the mounting structure functions as a connection structure that connects two or more pipe members to each other, both of the two pipe members may be supported and joined by press-fitting a tubular projecting portion into the expanded pipe portion.

In the above mounting structure, the pedestal may be divided into a plurality of portions.
By dividing the pedestal into a plurality of parts, the size of each part is reduced, and the manufacture and transportation of the pedestal are facilitated.

  According to another viewpoint of this invention, the pipe structure containing said attachment structure is provided.

  As described above, according to the present invention, stress concentration is prevented and the influence of environmental conditions is reduced in a pipe structure in which a pipe member having a tapered pipe formed at the end is used. Can do.

It is a longitudinal section of the basic structure concerning a 1st embodiment of the present invention. It is a longitudinal cross-sectional view of the basic structure which concerns on the 2nd Embodiment of this invention. It is sectional drawing in the III-III line of the basic structure shown by FIG. It is a longitudinal cross-sectional view which shows the example of the steel pipe structure which concerns on the 3rd Embodiment of this invention. It is a fragmentary sectional view in the VV line of the steel pipe structure shown in FIG. It is a figure which shows the example of the steel pipe structure which concerns on the 4th Embodiment of this invention. It is a longitudinal section showing the 1st example in which a base is divided into a plurality of parts in an embodiment of the present invention. It is a cross-sectional view which shows the 1st example by which a base is divided | segmented into a several part in embodiment of this invention. It is a figure which shows the modification of the example shown by FIG. 7A and 7B. It is a figure which shows another modification of the example shown by FIG. 7A and 7B. It is a figure which shows another modification of the example shown by FIG. 7A and 7B. It is a longitudinal cross-sectional view which shows the 2nd example by which a base is divided | segmented into a some part in embodiment of this invention. It is a figure which shows the modification of the example shown by FIG. It is a figure which shows the modification of the example shown by FIG. It is a figure which shows the state which two parts shown by FIG. 10A were mutually engaged. It is a figure which shows another modification of the example shown by FIG.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present specification and drawings, components having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

(First embodiment)
FIG. 1 is a longitudinal sectional view of a foundation structure according to the first embodiment of the present invention. A basic structure 1 shown in FIG. 1 is composed of a steel pipe 2 having a tapered pipe expansion portion 2a formed on one end side in the length direction (lower end side in FIG. 1), and a pedestal 3. Here, in the pipe expansion part 2a, the diameter of the steel pipe 2 gradually increases toward the end part side due to the tapered shape. The expanded pipe portion 2 a is formed in a section having a predetermined length L including the end portion of the steel pipe 2. Straight sections 2b are formed in the other sections. In the straight portion 2b, the diameter of the steel pipe 2 is constant, and the wall thickness is also substantially constant. Moreover, the wall thickness of the pipe expansion part 2a is constant over substantially the entire length of the pipe expansion part 2a. The angle θ ₁ formed by the tube wall of the expanded pipe portion 2a with respect to the longitudinal axis is hereinafter also referred to as a taper angle of the expanded pipe portion 2a. As an example, the length L is about twice the diameter of the steel pipe 2 in the section other than the expanded portion 2a, and the taper angle θ ₁ is set to be tan θ ₁ = 1/150. Various designs are possible without limitation. The pedestal 3 includes a base plate 4 that is a main body portion and a tubular projecting portion 5 that projects from the base plate 4. As shown in the drawing, the tubular projecting portion 5 is press-fitted into the expanded pipe portion 2a, and the steel pipe 2 is applied by the support pressure and frictional force acting between the outer peripheral surface 51 of the tubular projecting portion 5 and the inner peripheral surface 2c of the expanded tube portion 2a. And the base 3 are joined.

  Here, in the present embodiment, the pedestal 3 is continuously formed using cast steel, cast iron, or the like, and the base plate 4 and the tubular projecting portion 5 are continuous via a rounded connecting portion 6. Here, in the present specification, “continuous” does not simply mean that the shapes of the plurality of portions are continuous, but also means that the material composition of the plurality of portions is continuous. For example, when the base 3 including the base plate 4 and the tubular protrusion 5 is formed by casting, the material composition of the base plate 4 and the tubular protrusion 5 is continuous. By continuously forming the pedestal 3 in this manner, for example, a discontinuous portion of the material composition due to welding is not formed between the base plate 4 and the tubular protruding portion 5, and stress concentration in the pedestal 3 is prevented. Can do. In the case of casting, since the overall material composition is substantially uniform, stress concentration is unlikely to occur in the entire pedestal 3. In casting, since the degree of freedom of the shape of the manufactured part is high, for example, the shape of the inner peripheral surface 52 of the tubular projecting portion 5 as described later can be freely designed while ensuring the integrity.

In order to enable joining by the support pressure and frictional force between the steel pipe 2 and the pedestal 3 as described above, the outer peripheral surface 51 of the tubular projecting portion 5 has a tapered shape corresponding to the expanded portion 2a of the steel pipe 2, that is, The tubular protrusion 5 has a shape that gradually tapers as it goes to the end opposite to the base plate 4 (upper end in FIG. 1). The angle θ ₂ formed by the outer peripheral surface 51 with respect to the longitudinal axis of the tubular protrusion 5 (axis perpendicular to the base plate 4) is also referred to as a taper angle of the outer peripheral surface 51 below. In the present embodiment, the taper angle theta ₂ of the outer peripheral surface 51 is approximately equal to the taper angle theta ₁ of the expanded portion 2a, or slightly smaller than the taper angle theta _1.

The outer diameter of the tubular projection 5, the tapered shape of the outer circumferential surface 51 as described above, the first outer diameter D ₁ at the lower end of the tubular projection 5 (a boundary between the connecting part 6), the tubular projection 5 changes to a second outer diameter D ₂ at the upper end. First outer diameter D ₁ is larger than the inner diameter d ₁ of the end opening of the expanded pipe portion 2a, the second outer diameter D ₂ is smaller than the inner diameter d ₁ of the end opening. Due to such a structure, when the tubular projecting portion 5 is press-fitted from the end opening of the expanded tube portion 2a to an appropriate depth, either the expanded tube portion 2a or the tubular projecting portion 5 or both are elastically deformed. By utilizing the restoring force of the elastic deformation, it is possible to efficiently transmit the force between the inner peripheral surface 2c of the tube expansion portion 2a and the outer peripheral surface 51 of the tubular projecting portion 5.

On the other hand, unlike the outer peripheral surface 51, the inner peripheral surface 52 of the tubular projecting portion 5 does not have a tapered shape. In the illustrated example, the inner peripheral surface 52 of the tubular protrusion 5 has a straight shape. In other words, the inner diameter d ₂ of the tubular projection 5 is constant from the lower end of the tubular projection 5 (a boundary between the connecting part 6) to the upper end. As a result, the wall thickness at the upper end (the end opposite to the base plate 4) of the tubular protrusion 5 is thinner than the wall thickness at the lower end (the end on the base plate 4 side). As a result, the tubular protrusion 5 gradually becomes thinner as it goes from the lower end to the upper end as a whole. In this way, the weight of the base 3 can be reduced while reducing the stress applied to the lower end of the tubular protrusion 5. Further, in the example shown, by the inner diameter d ₂ of the tubular projection 5 is constant from the lower end to the upper end, there is no recessed portion when viewed from the opening at the upper end inside of the tubular projection 5, the base 3 by casting Is easy to manufacture.

  In order to obtain the same effect as described above, the inner peripheral surface 52 of the tubular projecting portion 5 has a tapered shape opposite to the tapered shape of the outer peripheral surface 51 (that is, a funnel shape opened upward in the figure). You may have. Alternatively, when the inner peripheral surface 52 does not have a tapered shape, the inner diameter of the tubular protruding portion 5 is not constant from the lower end to the upper end, and the inner diameter at the upper end becomes larger than the inner diameter at the lower end due to a step formed in the middle. It may be. Even in such a case, the thickness at the upper end of the tubular protrusion 5 is thinner than the thickness at the lower end.

  In addition, in the basic structure 1, the electrical component 7 is attached to the inner peripheral surface 52 of the tubular projecting portion 5. For example, when the steel pipe 2 is used as a support for installing lighting or a sign, it is necessary to attach an electrical component 7 connected to a device such as a lighting device installed on the upper part to the foundation structure 1. For example, in the case of a basic structure in which a steel pipe is inserted inside a hollow tube, the electric component cannot be attached inside the hollow tube, and thus the electrical component is attached inside the steel tube. In this case, since it is difficult to insert and attach the electrical component from the end opening of the steel pipe, an opening for attaching the electrical component is formed on the peripheral surface of the steel pipe. However, since stress concentration is likely to occur in the opening, it is desirable to reduce the opening as much as possible. In the foundation structure 1 according to the present embodiment, the steel pipe 2 is located outside the tubular protrusion 5, and therefore the electrical component 7 is attached to the inner peripheral surface 52 of the tubular protrusion 5 before joining the steel pipe 2 and the pedestal 3. It is possible to reduce the number of openings formed in the steel pipe 2 for mounting the electrical component 7.

  According to the first embodiment of the present invention as described above, the steel pipe 2 and the pedestal 3 can be securely supported and joined in the foundation structure 1. In the support joint, since no weld is formed between the steel pipe 2 and another member, stress concentration on the weld does not occur. Moreover, according to this embodiment, in the junction part of the steel pipe 2 and the tubular protrusion part 5, the outer edge part of the boundary part of the inner peripheral surface of the steel pipe 2 and the outer peripheral surface of the tubular protrusion part 5 is rainwater. Since it is directed in the direction (downward) where it is difficult to collect water, the influence of environmental conditions such as rainwater can be reduced.

  Moreover, according to this embodiment, since the base plate 4 and the tubular projecting portion 5 of the pedestal 3 are continuously formed using cast steel, no weld is formed between the portions of the pedestal 3, and accordingly. No stress concentration on the weld. Furthermore, according to the present embodiment, the weight of the pedestal 3 is reduced while reducing the stress applied to the lower end of the tubular protrusion 5 by reducing the thickness of the tubular protrusion 5 of the pedestal 3 toward the upper end. Can be reduced. Moreover, in this embodiment, an electrical component can be attached to the inner peripheral surface 52 of the tubular projecting portion 5 to reduce the opening formed in the steel pipe 2.

(Second Embodiment)
FIG. 2 is a longitudinal sectional view of the foundation structure according to the second embodiment of the present invention. 3 is a cross-sectional view taken along line III-III of the basic structure shown in FIG. As a difference from the first embodiment described above, in the basic structure 11 shown in FIGS. 2 and 3, the upper end of the tubular protrusion 5 (the end opposite to the base plate 4) continues to the outer peripheral surface 51. Thus, the oblique surface 53 is formed. Further, in the foundation structure 11, a groove 54 extending in the longitudinal direction of the tubular protruding portion 5 is formed along the outer peripheral surface 51. As shown in FIG. 2, the groove 54 is connected to the oblique surface 53 and extends to the vicinity of the lower end of the tubular projecting portion 5 that is not covered by the expanded portion 2 a of the steel pipe 2. As shown in FIG. 3, four grooves 54 arranged at equal intervals in the circumferential direction are formed on the outer peripheral surface 51 of the tubular projecting portion 5. Note that the number of the grooves 54 illustrated is an example, and a larger or smaller number of grooves 54 may be formed in other examples. Further, the interval between the grooves 54 in the circumferential direction is not necessarily equal. Further, the groove 54 is not necessarily provided. In addition to the above, the configuration of the foundation structure 11 according to this embodiment is the same as that of the foundation structure 1 according to the first embodiment.

The beveled surface 53 has a tapered shape with a taper angle θ ₃ larger than the taper angle θ ₂ of the outer peripheral surface 51, thereby forming a bevel at the upper end portion of the tubular projecting portion 5. By forming such an oblique angle, for example, water droplets originating from rainwater and the like and having been transmitted from the upper portion of the steel pipe 2 to the inner peripheral surface 2c are guided to the outer peripheral surface 51 side of the tubular projecting portion 5, and further, the grooves 54 are formed. Then, it is discharged to the outside of the steel pipe 2 or the tubular protrusion 5. As a result, it is possible to prevent water droplets from accumulating inside the tubular protrusion 5 and the electrical component 7 from being affected by the water droplets.

(Third embodiment)
FIG. 4 is a longitudinal sectional view showing an example of a steel pipe structure according to the third embodiment of the present invention. FIG. 5 is a partial cross-sectional view taken along line VV of the steel pipe structure shown in FIG. In the column beam structure 20 shown in FIG. 4, a steel pipe 21 is used as a support column. A tapered pipe expansion portion 21 a is formed at one end (lower end) of the steel pipe 21. The tubular projecting portion 5 of the pedestal 3 is press-fitted into the expanded pipe portion 21a, and thereby the basic structure similar to that of the first embodiment is configured. On the other hand, at the other end portion (upper end portion) of the steel pipe 21, a tapered-shaped contracted tube portion 21c is formed. In the contracted tube portion 21c, the steel tube 21 is gradually tapered toward the other end (upper end) due to the tapered shape. The contracted tube portion 21 c is press-fitted into a tapered cavity 24 formed in the connecting member 22. Here, the connecting member 22 is continuously formed of cast steel as in the case of the base 3, and is perpendicular to the main body 23, the cavity 24 formed in the main body 23, and the axis of the cavity 24 from the main body 23. And a tubular projecting portion 25 projecting in the direction. The cavity 24 has a tapered shape corresponding to the reduced tube portion 21 c of the steel pipe 21, that is, a shape that gradually decreases in diameter from the opening of the cavity 24 toward the back (bottom surface) side. The steel pipe 21 and the connecting member 22 are joined by the supporting pressure and the frictional force acting between the outer peripheral surface of the contracted tube portion 21 c and the inner peripheral surface of the cavity 24.

  Here, as in the case of the tubular protrusion 5 of the pedestal 3 constituting the foundation structure 1, the inner diameter of the cavity 24 is changed from the first inner diameter at the lower end (opening) of the cavity 24 to the upper end (bottom surface and It changes to the second inner diameter at the boundary between the rounded parts on both sides. The first inner diameter is larger than the outer diameter of the end of the contracted tube portion 21c of the steel pipe 21, and the second inner diameter is smaller than the outer diameter of the end of the contracted tube portion 21c of the steel tube 21. Accordingly, when the contracted tube portion 21c is press-fitted from the opening of the cavity 24 to an appropriate depth, either the contracted tube portion 21c or the body portion 23 of the connecting member 22 where the cavity 24 is formed or both are elastically deformed. To do. By utilizing the restoring force of elastic deformation, it is possible to efficiently transmit force between the outer peripheral surface of the contracted tube portion 21 c and the inner peripheral surface of the cavity 24.

  On the other hand, the tubular projecting portion 25 of the connecting member 22 is press-fitted into the inner peripheral surface side of a tapered pipe expanding portion 27a formed at one end portion in the length direction of a steel pipe 27 used as a beam. Here, in the pipe expansion part 27a, the diameter of the steel pipe 27 gradually increases toward the end side. On the other hand, the outer peripheral surface of the tubular projecting portion 25 has a tapered shape corresponding to the expanded portion 27a of the steel pipe 27, that is, a shape that gradually tapers toward the end of the tubular projecting portion 25 opposite to the main body portion 23. The steel pipe 27 and the connecting member 22 are joined by the supporting pressure and the frictional force acting on the inner peripheral surface of the expanded pipe portion 27a and the outer peripheral surface of the tubular projecting portion 25. The relationship between the outer diameter of the tubular projecting portion 25 and the inner diameter of the expanded tube portion 27a for efficient force transmission is the tubular projecting portion in the basic structure 1 described above as the first embodiment. 5 is the same as the relationship between the outer diameter of the steel pipe 2 and the inner diameter of the expanded portion 2a of the steel pipe 2, and repeated description is omitted.

  As a difference from the basic structure 1, in the connecting member 22, a sloped surface 26 that follows the outer peripheral surface of the tubular projecting portion 25 is formed on the side that is upward when the column beam structure 20 is assembled. The gradient surface 26 is a downward gradient that connects the boundary with the outer peripheral surface of the tubular projecting portion 25 to the surface of the main body portion 23 of the connecting member 22. By forming such a gradient surface 26, for example, when the column beam structure 20 is installed outdoors, rainwater is prevented from entering between the outer peripheral surface of the tubular projecting portion 25 and the expanded portion 27a of the steel pipe 27. Is done. By forming the sloped surface 26 so that the boundary between the outer peripheral surface of the tubular projecting portion 25 and the sloped surface 26 and the end of the expanded tube portion 27a when the tubular projecting portion 25 is press-fitted are formed, the bearing pressure In addition, rainwater can be prevented from entering while ensuring the maximum frictional force. Alternatively, from the viewpoint of preventing rainwater from entering, the inclined surface 26 may enter the inside of the expanded pipe portion 27a. Also in this case, as shown in FIG. 5, most of the outer peripheral surface of the tubular projecting portion 25 is in contact with the inner peripheral surface of the expanded tube portion 27a, so that the supporting pressure and the frictional force are maintained.

  In the above-mentioned column beam structure 20, the basic structure constituted by the steel pipe 21 and the pedestal 3 is an example of a steel pipe structure mounting structure according to the embodiment of the present invention. Further, the column beam structure 20 includes another mounting structure constituted by the steel pipe 27 and the connecting member 22. In this attachment structure, the connecting member 22 constitutes a pedestal for attaching the steel pipe 27 in the horizontal direction. The tubular projecting portion 25 projects from the pedestal and is press-fitted into the expanded portion 27 a of the steel pipe 27. Further, the mounting structure described above includes a steel pipe 21 having a tapered pipe contraction part 21c formed at the upper end, and a cavity into which the contraction pipe part 21c is press-fitted into the main body part 23 of the connecting member 22 constituting the base. 24 is formed. That is, the above mounting structure functions as a connection structure that connects the two steel pipes 21 and 27 to each other. As described above, the mounting structure according to the embodiment of the present invention is applied not only as a basic structure but also to various types of mounting structures for steel pipe structures.

  In addition, the example of the steel pipe structure which concerns on embodiment of this invention is not restricted to the column beam structure 20 which concerns on said 3rd Embodiment, For example, a steel pipe structure which does not have a beam, such as an illumination lamp and a sign, is used. Including. In the steel pipe structure, the steel pipe does not necessarily have to be used as a column, and may be used exclusively as a beam. In these cases, the steel pipe does not necessarily have a pipe expansion part or a contraction pipe part at both ends. For example, the steel pipe may have a pipe expansion part only at one end. Further, in the above example, the column beam structure 20 has been described as including the foundation structure 1 according to the first embodiment. However, the column beam structure including the foundation structure 11 according to the second embodiment is also configured similarly. Is possible.

  FIG. 6 is a diagram showing an example of a steel pipe structure according to the fourth embodiment of the present invention. In the column beam structure 30 shown in FIG. 4, the steel pipes 31, 32, and 33 are used as columns, and the steel pipes 34 and 35 are used as beams. In each of the steel pipes 31, 32, and 33, tapered end pipe portions 31a, 32a, and 33a that increase in diameter toward the lower end portion are formed at one end portion (lower end portion). Tubular protrusions 36a, 37a, and 38a of pedestals 36, 37, and 38 are press-fitted into the expanded pipe portions 31a, 32a, and 33a, respectively. Moreover, in each of the steel pipes 31, 32, and 33, taper-shaped contraction pipe portions 31b, 32b, and 33b that taper toward the upper end portion are formed at the other end portion (upper end portion). The contracted tube portions 31b, 32b, and 33b are press-fitted into the cavities 39a, 40a, and 41a of the connecting members 39, 40, and 41, respectively. In addition, the relationship between each steel pipe, a base, and a connection member is the same as the relationship between the steel pipe 21, the base 3, and the connection member 22 demonstrated with reference to FIG. 4 above.

  In each of the steel pipes 34 and 35, tapered expanded pipe portions 34a, 34b, 35a, and 35b are formed at both ends so as to increase in diameter toward the respective ends. Tubular protrusions 39b, 40b, 40c, and 41b of the connecting members 39, 40, and 41 are press-fitted into the inner peripheral surfaces of the expanded pipe portions 34a, 34b, 35a, and 35b, respectively. The relationship between each steel pipe and the connecting member is the same as the relationship between the steel pipe 27 and the connecting member 22 described above with reference to FIG.

  In the example of the steel pipe structure described above as the third and fourth embodiments, the expanded portion and the contracted portion of the steel pipe are interchangeable. That is, in another example, the expanded tube portion in the above example may be replaced with a contracted tube portion, or the contracted tube portion may be replaced with an expanded tube portion. However, for example, in the column beam structure 20 shown in FIG. 4, the upper end portion of the steel pipe 21 is, for example, the contracted tube portion 21 c rather than the expanded tube portion, so that rainwater can be prevented from entering the inside of the steel tube 21, for example. It is preferable from the viewpoint of. For the same reason, the lower end portion of the steel pipe 21 is preferably the expanded pipe portion 21a rather than the contracted tube portion.

(Example where the pedestal is divided into multiple parts)
7A and 7B are cross-sectional views showing a first example in which the pedestal is divided into a plurality of portions in the embodiment of the present invention as described above. The relationship of each figure is shown by the VIIA-VIIA line and the VIIB-VIIB line. In the illustrated example, the pedestal 3 is divided into two parts 3 a and 3 b along a plane including the axis of the tubular protrusion 5. Each of the two portions 3a and 3b includes divided base plates 4a and 4b and divided tubular protrusions 5a and 5b. The two parts 3a and 3b of the pedestal 3 may be joined in advance by welding, for example, or joined until the tubular protrusion 5 is press-fitted into the expanded portion 2a of the steel pipe 2 (see FIG. 1 and the like). It does not have to be. The support pressure in the radial direction of the steel pipe acting between the outer peripheral surface 51 of the tubular projecting portion 5 and the inner peripheral surface 2c of the expanded tube portion 2a acts in the direction of pressing the two portions 3a, 3b of the base 3 toward each other. It is possible to maintain the state where the two portions 3a and 3b are joined without using welding or the like.

  When joining the two parts 3a and 3b of the base 3 without using welding or the like as described above, a water stop material may be applied to the joint surfaces 3aa and 3ba. By applying a water-stopping material to the joint surfaces 3aa and 3ba at the portion of the tubular projecting portion 5, for example, water droplets derived from rain water and the like and transmitted from the upper part of the steel pipe 2 to the inner peripheral surface 2c are formed between the joint surfaces 3aa and 3ba. It is possible to prevent entering the inside of the tubular projecting portion 5 through the gap. Further, by applying a water-stopping material to the joint surfaces 3aa and 3ba at the base plate 4, rainwater and the like enter the inside of the tubular projecting portion 5 from the base plate 4 side through the gap between the joint surfaces 3aa and 3ba. Can be prevented. The waterstop material is, for example, an elastomer having water expandability, for example, natural rubber or chloroprene rubber blended with a high molecular substance such as starch, cellulose, polyacrylate, or polyvinyl alcohol. Etc. can be used.

  FIG. 7C is a diagram showing a modification of the example shown in FIGS. 7A and 7B. In the example shown in FIG. 7C, the pedestal 3 is divided into four portions 3 c, 3 d, 3 e, and 3 f along a plane that includes the axis of the tubular protrusion 5. Each of the four portions 3c to 3F includes divided base plates 4c, 4d, 4e, and 4f, and divided tubular protrusions 5c, 5d, 5e, and 5f. Other points are the same as in the example shown in FIG. 7A and FIG. 7B, and redundant description is omitted.

  8A and 8B are diagrams showing another modification of the example shown in FIGS. 7A and 7B. The relationship of each figure is shown by the VIIIA-VIIIA line and the VIIIB-VIIIB line. In the illustrated example, the pedestal 3 is divided into two parts 3A and 3b as in the example of FIGS. 7A and 7B. However, in this example, protrusions 3ab and grooves 3bb having shapes corresponding to each other are formed on the joint surfaces 3aa, 3ba of the two portions 3a, 3b. When the two protrusions 3ab and the groove 3bb are engaged with each other to join the two portions 3a and 3b of the base 3 without using welding or the like, the tubular protrusion 5 is press-fitted into the expanded portion 2a of the steel pipe 2 It is easy to maintain a state in which the two parts 3a and 3b are combined. Further, in each of the tubular projecting portion 5 and the base plate 4, it is possible to prevent water droplets or rainwater from entering the inside of the tubular projecting portion 5. In addition, in this example, a water stop material may be applied to the joint surfaces 3aa and 3ba of the two portions 3a and 3b including the protrusion 3ab and the groove 3bb.

  FIG. 9 is a longitudinal sectional view showing a second example in which the pedestal is divided into a plurality of portions in the embodiment of the present invention. In the illustrated example, the pedestal 3 is divided into two parts 3p and 3q on a plane perpendicular to the axis of the tubular protrusion 5. One portion 3p includes a base plate 4 and a divided tubular protrusion 5p. The other portion 3q includes a divided tubular protrusion 5q. The two parts 3p and 3q of the pedestal 3 may be joined in advance by welding, for example, or joined until the tubular protruding part 5 is press-fitted into the expanded part 2a of the steel pipe 2 (see FIG. 1 and the like). It does not have to be. If the joint surfaces 3pa and 3qa are above the lower end of the expanded pipe portion 2a, the support pressure in the radial direction of the steel pipe acting between the outer peripheral surface 51 of the tubular projecting portion 5 and the inner peripheral surface 2c of the expanded pipe portion 2a is as follows. Since the two parts 3p and 3q of the pedestal 3 act in a direction in which the two parts 3p and 3q are pressed toward each other, it is possible to maintain the joined state of the two parts 3p and 3q without using welding or the like. Similarly to the above example, when the two portions 3p and 3q are joined without using welding or the like, a water stop material may be applied to the joint surfaces 3pa and 3qa.

  10A and 10B are diagrams showing a modification of the example shown in FIG. The relationship of each figure is shown by the XA-XA line and the XB-XB line. FIG. 10C is a diagram illustrating a state in which the two portions illustrated in FIG. 10A are engaged with each other. In the illustrated example, the pedestal 3 is divided into two parts 3p and 3q as in the example of FIG. However, in this example, as shown in FIG. 10A, a groove portion 3pb and a flange portion 3qb having shapes corresponding to each other are formed in the two portions 3p and 3q. The groove portion 3pb is formed on the inner peripheral surface of the tubular projecting portion 5, and extends in parallel with the joint surface 3pa, that is, in the circumferential direction of the tubular projecting portion 5. As shown in FIG. 10B, the joint surface 3pa and the groove 3pb communicate with each other through cutouts 3pc formed at four locations. The flange portions 3qb are formed at four locations corresponding to the cutout portions 3pc. After inserting the flange portion 3qb through the notch portion 3pc, the flange portion 3qb can be engaged with the groove portion 3pb by rotating the portion 3q around the axis of the tubular protrusion 5 with respect to the portion 3p. By engaging the two portions 3p and 3q with each other using the groove portion 3pb and the flange portion 3qb in this manner, bending against the steel pipe 2, that is, against stress in a direction perpendicular to the axis of the tubular projecting portion 5. The state where the two portions 3p and 3q are joined can be maintained.

  FIG. 11 is a diagram showing another modification of the example shown in FIG. In the illustrated example, the pedestal 3 is divided into two parts 3p and 3q as in the example of FIG. However, in this example, flanges 3pd and 3qd are formed on the joint surfaces 3pa and 3qa of the two portions 3p and 3q, and the flanges 3pd and 3qd are fastened to each other by a bolt 3pe and a nut 3qe. In this example, by arranging a plurality of sets of bolts 3pe and nuts 3qe, compression or tension (stress in the axial direction of the tubular protrusion 5) against the steel pipe 2 without welding between the two portions 3p, 3q, The two parts 3p and 3q are maintained in a joined state against bending (stress in a direction perpendicular to the axis of the tubular protrusion 5) and rotation (moment about the axis of the tubular protrusion 5). be able to.

  By dividing the pedestal 3 into a plurality of parts as in the above example, the size of each part is reduced and the manufacture and transportation of the pedestal 3 are facilitated. Even when the pedestal 3 is divided into a plurality of portions, the steel pipe 2 and the pedestal 3 can be reliably friction-bonded and support-bonded as in the first to third embodiments. Although a plurality of portions of the pedestal 3 may be welded, a welded portion is not formed between the steel pipe 2 and another member, and therefore stress concentration on the welded portion is unlikely to occur. In addition, water droplets or rainwater can be formed on the inner side of the tubular projecting portion 5 by bringing the plurality of portions of the pedestal 3 into close contact with each other, providing the engagement structure as described above, or applying a water stop material to the joint surface. Can be prevented, so that the influence of environmental conditions such as rainwater can be reduced as in the first to third embodiments. Further, by dividing the pedestal 3 into a plurality of parts other than the boundary between the base plate 4 and the tubular projecting portion 5, the base plate 4 and the tubular projecting portion 5 are made of cast steel in the same manner as in the first to third embodiments. It is possible to form continuously by using and reduce stress concentration on the welded portion. Further, by reducing the thickness of the tubular projecting portion 5 toward the upper end portion, the weight of the pedestal 3 can be reduced while reducing the stress applied to the lower end portion of the tubular projecting portion 5. The point which can attach the electrical component to a surrounding surface and can reduce the opening part formed in the steel pipe 2 is the same as that of the example of 1st to 3rd embodiment.

  7A to 11, the example in which the pedestal 3 as shown in FIGS. 1 to 3 is divided into a plurality of portions has been described. However, the connecting member 22 ( Similarly, a portion including the tubular projecting portion 25 can be divided into a plurality of portions, for example, for a pedestal for attaching the steel pipe 27 in the horizontal direction.

  Although exemplary embodiments of the present invention have been described above, the technical scope of the present invention is not limited to these embodiments, and the present invention is within the scope of the technical idea described in the claims. Including embodiments that have been changed or modified in accordance with what can be conceived by those having ordinary skill in the art.

  For example, in the above embodiment, a basic structure including a steel pipe and a pedestal formed of cast steel has been described. However, the material of the pipe member and the pedestal is not limited to steel, and elastic deformation as described in the above embodiment is performed. Any material may be used as long as it is generated. Further, the pipe member and the pedestal may be formed of different materials.

  For example, in the above-described embodiment, the base plate that is the main body portion of the pedestal and the tubular protruding portion are described as being continuously formed by casting. However, the main body portion and the tubular protruding portion are continuously formed by a method other than casting. It may be formed automatically.

DESCRIPTION OF SYMBOLS 1,11 ... Base structure, 2, 21, 27 ... Steel pipe, 2a, 21a, 27a ... Expanded part, 2b ... Straight part, 21c ... Contraction part, 3 ... Base, 4 ... Base plate, 5,25 ... Tubular protrusion , 51, outer peripheral surface, 52, inner peripheral surface, 53, beveled surface, 54, groove, 7, electrical component, 20, 30, column beam structure, 22, connecting member, 23, main body, 24, cavity, 26, ... gradient surface.

Claims (11)

A pipe structure mounting structure,
A tubular member including a tapered tube-shaped expanding portion formed in a section of a predetermined length including at least one end, and a straight section formed in a section other than the section of the predetermined length;
A pedestal including a main body part and a tubular projecting part protruding from the main body part and press-fitted into the inner peripheral surface side of the expanded pipe part,
The outer peripheral surface of the tubular projecting portion has a tapered shape corresponding to the inner peripheral surface of the expanded tube portion,
The outer diameter of the tubular projecting portion is a second outer diameter that is smaller than the inner diameter of the end opening from the first outer diameter that is larger than the inner diameter of the end opening of the tube expansion portion due to the tapered shape of the outer peripheral surface. Mounting structure that changes up to.   The mounting structure according to claim 1, wherein the main body portion and the tubular projecting portion of the pedestal are formed continuously.   3. The attachment structure according to claim 1, wherein a thickness of the tubular projecting portion is reduced toward an end portion on a side opposite to the main body portion.   The attachment structure according to any one of claims 1 to 3, further comprising an electrical component attached to the inner peripheral surface of the tubular protrusion.   The mounting structure according to any one of claims 1 to 4, wherein the tubular projecting portion includes a beveled surface formed following the outer peripheral surface at an end opposite to the main body portion.   The mounting structure according to claim 5, wherein the tubular projecting portion has a groove connected to the oblique surface and extending along the outer peripheral surface in the longitudinal direction of the tubular projecting portion.   The mounting structure according to claim 1, wherein the main body is a base plate. The attachment structure further includes a tube member including a tapered tube-shaped contraction portion formed at at least one end portion,
The pedestal further includes a cavity formed in the main body portion and into which the contracted tube portion is press-fitted,
The inner peripheral surface of the cavity has a tapered shape corresponding to the contracted tube portion,
Due to the tapered shape of the inner peripheral surface of the cavity, the inner diameter of the cavity is smaller than the outer diameter of the end portion of the contraction tube portion from the first inner diameter larger than the outer diameter of the end portion of the contraction tube portion. The mounting structure according to claim 1, wherein the mounting structure changes to an inner diameter of 2. The attachment structure further includes an additional pipe member including a tapered pipe expanding part formed on at least one end part,
The mounting structure according to claim 1, wherein the pedestal further includes an additional tubular protruding portion that protrudes from the main body portion and is press-fitted into the expanded portion of the additional tube member.   The mounting structure according to claim 1, wherein the pedestal is divided into a plurality of portions. The pipe structure containing the attachment structure of any one of Claims 1-10.

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