JP2002356923A - Joint structure for concrete-filled cylindrical body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a joint structure for a concrete-filled cylindrical body capable of easily connecting two cylindrical bodies to each other through concrete, and reducing man-hours for connection work at a site. SOLUTION: In this joint structure 4 for a concrete-filled steel pipe 1, end parts of two steel pipes 2 are connected to each other through concrete 3 filled inside the steel pipes 2. Plural dowels 11 protruded outward in the direction of an axial center 10 are fixed to inside parts at the end part of the steel pipe 2, protruded parts 12 of the dowels 11 are inserted into the other steel pipe 2, and the dowels 11 are connected to the other steel pipe 2 by the concrete 3. The end parts of the two steel pipes 2 are thus connected to each other through the plural dowels 11 and the concrete 3, and the end parts of the two steel pipes 2 need not be connected by welding or bolting. The two steel pipes 2 can thus be easily connected, and man-hours for connection work at a site can be reduced. Since tensile force can be transmitted by the dowels, tensile strength can be secured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joint structure for a concrete-filled cylindrical body, and more particularly to a structure for connecting two cylindrical bodies having the same diameter or different diameters with a dowel and concrete.

[0002]

2. Description of the Related Art In recent years, in various structures such as bridge piers and bridge girders, a concrete-filled tubular body in which a steel tubular body having high tensile strength is filled with concrete having excellent compressive strength has been adopted. In this concrete-filled tubular body, after connecting a plurality of tubular bodies, concrete is filled into the tubular body. For example, in the case of a concrete-filled steel pipe using a steel pipe as the tubular body, two concrete bodies are used. In order to connect the steel pipes, the ends of the steel pipes are generally connected by butt welding or the ends of the steel pipes are connected by bolts.

[0003] By the way, the above-mentioned connection work of steel pipes is carried out on site, and large-diameter steel pipes are often used for concrete-filled steel pipes. Therefore, when connecting steel pipes by welding as described above, a skilled welder is required, the number of steps required for welding one ring is increased, and the cost of the connection work is increased. Further, even when connecting by bolts, the number of bolts increases due to the large diameter of the steel pipe, and the number of steps of the connection work also increases.

In order to solve the above problems, for example,
JP-A-5-295800 discloses a joint structure of a concrete-filled steel pipe as described below. As shown in FIG. 10, this joint structure 100 includes steel pipes 101 having different diameters.
A plurality of grooves 101a are provided on the inner peripheral portion at the right end of the large-diameter tube 101, and a plurality of grooves 102a are also provided on the outer peripheral portion of the left end of the small-diameter tube 102. I have. In this joint structure 100, to connect the two steel pipes 101 and 102, the left end of the small diameter pipe 102 is inserted into the right end of the large diameter pipe 101, and then the concrete 103 is connected to the two steel pipes 101 and 102. Fill inside. Since the concrete 103 is also filled between the large-diameter pipe 101 and the small-diameter pipe 102, the concrete 103
Is solidified, the large-diameter pipe 101 and the small-diameter pipe 102 are connected via the concrete 103. On this occasion,
The relative movement between the inner peripheral surface of the large-diameter pipe 101 and the outer peripheral surface of the small-diameter pipe 102 and the concrete 103 is regulated by the grooves 101a and 102a, and the large-diameter pipe 101 and the small-diameter pipe 102 are firmly connected. .

On the other hand, when connecting two steel pipes having the same diameter, as shown in FIG.
The steel pipe 111 is a short pipe 1 having a larger diameter than these steel pipes 111.
After being inserted into the left end portion and the right end portion, respectively, concrete 113 is filled inside the two steel pipes 111 and between the steel pipes 111 and the short pipes 112. Grooves 111a, 112 are formed on the outer peripheral surface of the end of the steel pipe 111 and the inner peripheral surface of the short pipe 112, respectively.
a is formed, and when the concrete 113 is solidified, each steel pipe 11
1 and the short pipe 112 are firmly connected, and the two steel pipes 111 are connected via the short pipe 112.

[0006]

In the joint structure of a concrete-filled steel pipe described in the above publication, although two steel pipes can be connected via concrete,
In the connection between frequently used same-diameter pipes, the connection is made via a short pipe, so that a short pipe is separately required. In addition, it is necessary to take measures to prevent concrete from leaking during the concrete filling from between the short pipe and the steel pipe, and there are two connection points (each of the two steel pipes and the short pipe), Connection man-hours increase. Further, it is necessary to perform machining to form a groove in the steel pipe or the short pipe, which increases the manufacturing cost of the steel pipe or the short pipe. An object of the present invention is to easily connect two cylindrical bodies having the same diameter via concrete, to reduce the number of man-hours for connection work on site, to reduce the manufacturing cost of cylindrical bodies, and the like. It is.

[0007]

According to a first aspect of the present invention, there is provided a joint structure of a concrete-filled cylindrical body, wherein ends of two metal cylindrical bodies are connected to each other via a concrete filled inside the cylindrical body. In the joint structure, the plurality of dowels protruding outward in the axial direction are fixed to the inner part of the end of at least one tubular member, and the projecting portions of the plurality of dowels are inserted into the other tubular member. The dowels are joined to the other tubular member by concrete, and the ends of the two tubular members are connected to each other via the plurality of dowels and concrete.

When connecting two cylindrical bodies, the protrusion of the dowel fixed to the end of at least one of the cylindrical bodies is inserted into the other cylindrical body. Concrete is filled in the inside of the shape. When the concrete solidifies, the protrusion of the dowel and the other tubular body are joined by concrete, and the ends of the two tubular bodies are connected to the dowel via the concrete. Since the two cylindrical bodies are not directly connected, the tensile force in the axial direction cannot be directly transmitted between the two cylindrical bodies, but since the tensile force is transmitted via the dowel, the shape of the dowel, Sufficient tensile strength can be secured by appropriately selecting the number and the like.

[0009] In the joint structure of the concrete-filled tubular body according to the second aspect, in the invention according to the first aspect,
A connection reinforcing portion for reinforcing the connection between the concrete and the dowel is provided. Accordingly, the concrete and the dowel are firmly connected by the joint reinforcing portion, and the dovetail does not move relative to the concrete, so that the tensile force is reliably transmitted through the dovetail.

According to a third aspect of the present invention, in the joint structure of a concrete-filled cylindrical body, the joint reinforcing portion is formed by:
It is characterized by comprising a plurality of concrete filling holes. Therefore, when the concrete is filled into the plurality of concrete filling holes and solidified, the relative movement of the dowel with respect to the concrete is restricted, and the concrete and the dovetail are firmly connected.

According to a fourth aspect of the present invention, in the joint structure of the concrete-filled cylindrical body, the joint reinforcing portion is
It is characterized by comprising a plurality of stud members fixed to the dowel. Therefore, the plurality of stud members are engaged with the solidified concrete, the relative movement of the dowel with respect to the concrete is restricted, and the concrete and the dovetail are firmly connected.

According to a fifth aspect of the present invention, in the joint structure of a concrete-filled cylindrical body, the joint strengthening portion is formed as follows.
It is characterized by comprising a plurality of waveform projections. Accordingly, the corrugated protrusion engages with the solidified concrete, so that the relative movement of the dowel with respect to the concrete is restricted, and the concrete and the dovetail are firmly connected.

A joint structure for a concrete-filled tubular body according to claim 6 is the invention according to any one of claims 1 to 5, characterized in that the tubular body is a steel pipe. Therefore, two concrete-filled steel pipes can be connected via the concrete and the dowel fixed to at least one concrete-filled steel pipe.

According to a seventh aspect of the present invention, in the joint structure for a concrete-filled tubular body, the other tubular body may be externally fitted to the end of the projecting portion of each of the dowels. A guide portion serving as a guide is formed. Therefore, the other cylindrical body can be externally fitted to each dowel while being guided by the guide portion.

[0015]

Embodiments of the present invention will be described. In the present embodiment, the present invention is applied to a joint structure for connecting two concrete-filled steel pipes of the same diameter in which concrete is filled in a steel pipe. As shown in FIGS. 1 to 4, a concrete-filled steel pipe 1 is configured by filling a steel pipe 2 (cylindrical body) having a high tensile strength with concrete 3 having an excellent compressive strength. The ends of the steel pipes 2 are connected via concrete 3 by a joint structure 4 unique to the present application.

As shown in FIGS. 1 and 2, on the inner peripheral portion at the end of each steel pipe 2, six steel plate dowels 11 (hereinafter referred to as dowels) extending in the direction of the axis 10 are divided into six equal parts on the circumference. Each is fixed in position. Since the dowels 11 of the left and right steel pipes 2 have the same structure, one dovetail 1 of the left steel pipe 2 is formed.
1 will be described below. The left half of Gibelle 11 is steel pipe 2
Is fixed to the inner peripheral portion at the right end by welding.
A projecting portion 12 projecting outward from the right end of the steel pipe 2 in the axial direction 10 is formed in the right half of the steel tube 2. To facilitate the insertion of the projection 12 into the other steel pipe 2, the projection 1
The width of 2 is formed slightly smaller than the width of the left half of the dowel 11, and there is a gap between the other steel pipe 2 and the protruding portion 12. Eight concrete filling holes 13 (coupling strengthening portions) are formed in the dowel 11 at substantially equal intervals in the direction of the axis 10. When the concrete 3 is filled into the eight concrete filling holes 13 and solidified, the dowel 11 is formed. Relative to concrete 3 is restricted, giving
1 and concrete 3 are firmly bonded.

As shown in FIGS. 3 and 4, when the two concrete-filled steel pipes 1 are connected by the joint structure 4, the projecting portions 12 of the six dowels 11 of each steel pipe 2 are connected to the other steel pipe 2. The dowels 11 and the other steel pipe 2 are inserted alternately, and are joined by the filled concrete 3. Therefore, the ends of the two steel pipes 2 are connected to the dowel 11 and the concrete 3.

Next, the operation of the joint structure 4 will be described.
In order to connect the two concrete-filled steel pipes 1 by the joint structure 4, as shown in FIG. 1, from the state where the two steel pipes 2 are separated, the protrusions 1 of the six dowels 11 of each steel pipe 2 are used.
2 are alternately inserted into the other steel pipe 2. At this time, as shown in FIG.
It is located in two equal parts.

Next, as shown in FIG. 3, when the concrete 3 is filled into the two steel pipes 2, the concrete 3 is also filled in the eight concrete filling holes 13 of each dowel 11. When the concrete 3 is solidified, the relative movement of the dowel 11 with respect to the concrete 3 is regulated, so that each dowel 11 and the concrete 3 are firmly connected.

As shown in FIG. 5, since the two steel pipes 2 are connected to the dowel 11 via the concrete 3, the steel pipe 2
There is no need to weld or bolt the outer peripheral surface. In this case, since the two steel pipes 2 are not directly connected, the tensile force in the direction of the axial center 10 cannot be transmitted directly between the two steel pipes 2, but this tensile force is transmitted by the twelve dowels 11. And the tensile strength in the vicinity of the connection portion can be secured.

According to the joint structure 4 described above, the two steel pipes 2
Is connected to the dowel 11 via concrete 3
There is no need to connect by welding, bolting, or the like at the site, and the number of connection work steps at the site can be significantly reduced. In addition, since two steel pipes 2 having the same diameter can be connected at one place, man-hours at the site when connecting the same diameter pipes can be reduced, and other members for connection (for example, short pipes) are not required. Become. Further, since a tensile force in the direction of the axis 10 can be transmitted between the two steel pipes 2 via the dowel 11,
Sufficient tensile strength can be secured.

Since eight concrete filling holes 13 are formed in each dowel 11, these concrete filling holes 1 are provided.
After filling concrete 3 with concrete 3, concrete 3
Is solidified, the relative movement of the dowel 11 with respect to the concrete 3 is regulated, so that each dowel 11 and the concrete 3 can be firmly connected. The width of the protruding portion 12 is formed slightly smaller than the width of the left half of the dowel 11. When the protruding portion 12 is inserted, a gap exists between the steel pipe 2 and the protruding portion 12. Insertion into the steel pipe 2 becomes easy.

The number of the dowels 11 is not limited to six for each steel pipe 2, and the dowel 11 is provided only for one steel pipe 2.
May be provided. For example, it is possible to increase the tensile strength of the connection portion as compared with the case where the number of the dowels 11 is increased and the dowels are connected by welding or bolts. Thus, Gibelle 1
Since various choices can be made for the material, shape, number, etc., of 1, the degree of freedom in design is increased. Further, the number of the concrete filling holes 13 is not limited to eight, and the number and the position thereof can be freely selected. Further, when the concrete is filled, the ends of the steel pipes 2 are sealed and welded to each other so as to prevent the concrete 3 from leaking from the ends of the steel pipes 2. After sandwiching in the end, concrete 3
May be filled inside.

Next, a description will be given of modified embodiments obtained by adding various modifications to the above-described embodiment. It is to be noted that the same components as those in the above embodiment are denoted by the same reference numerals, and the description thereof will be appropriately omitted. 1] Modification 1 (see FIG. 6) As shown in FIG. 6, in the joint structure 4A, a plurality of stud members 20 may be fixed to each dowel 11A of the steel pipe 2 by welding. The stud members 20 are engaged with the solidified concrete 3 so that the relative movement of the dowel 11A with respect to the concrete 3 is restricted, and the dovetail 11A and the concrete 3 are further firmly joined.

2] Modification 2 (see FIG. 7) As shown in FIG. 7, in the joint structure 4B, a plurality of corrugated protrusions 21 protruding toward the shaft center 10B are provided on each dowel 11B of the steel pipe 2. You may. These corrugated protrusions 21 engage with the solidified concrete 3, restricting relative movement of the dowel 11B with respect to the concrete 3, and the dovetail 11B and the concrete 3 are further firmly joined.

3] Modification 3 (see FIG. 8) As shown in FIG. 8, in the joint structure 4C, the other steel pipe 2 is externally fitted to the end of the projection 12C of each dowel 11C of the steel pipe 2. In this case, a guide portion 22 serving as a guide may be formed. The guide portion 22 makes it easy to externally fit the steel pipe 2 to the protruding portion 12C, and can reduce the number of man-hours for connection work on site.

4] Modification 4 (see FIG. 9) The present invention can be applied to a joint structure of a concrete-filled cylindrical body having a polygonal cross section. For example, as shown in FIG. 9, a case where the present invention is applied to a joint structure 4D of a concrete-filled tubular body 1D having a tubular body 2D having a rectangular cross section will be described. Rib 2
3 are provided, and dowels 11D are fixed to both sides of each rib 23 in an inner portion of the end of the tubular body 2D. These dowels 11D are joined to the concrete 3 in the same manner as in the above-described embodiment or a modification thereof, and the two tubular bodies 2D are connected via the dovetails 11D and the concrete 3. Further, the rib 23 may be provided with a connection strengthening portion for strengthening the connection with the concrete 3. As the connection strengthening portion, the same as the connection strengthening portion described in the above-described embodiment or its modification is used. Can be adopted.

[0028]

According to the invention of claim 1, in the joint structure of the concrete-filled tubular body, a plurality of dowels projecting in the axial direction are fixed to the inside portion of the end of at least one tubular body, After each dowel is inserted into the other tubular body, concrete is filled into the tubular body, and the ends of the two tubular bodies are connected to each other via the dowel and concrete. Can be connected without welding or bolting the cylindrical body of the pipe, making it easy to connect and without leaking concrete when filling concrete. The number of man-hours can be significantly reduced. Also, since the tensile force is transmitted between the two cylindrical bodies via the plurality of dowels,
Sufficient tensile strength can be ensured by appropriately selecting the shape and number of the dowels.

According to the second aspect of the present invention, each dowel is
Since the joint reinforcing part for strengthening the connection between the concrete and the dowel is provided, the concrete and the dowel are firmly connected by the joint reinforcing part, and the dovetail does not move relative to the concrete. The tensile force can be reliably transmitted between the two cylindrical bodies. Also,
There is no need to provide a connection strengthening portion by performing machining or the like on the tubular body itself, and the manufacturing cost of the tubular body can be reduced. In addition, the same effects as those of the first aspect are obtained.

According to the third aspect of the present invention, the coupling reinforcing portion
Since a plurality of concrete filling holes are provided, when the concrete is filled into the plurality of concrete filling holes and solidified, relative movement of the dowel with respect to the concrete is restricted, and the concrete and the dovetail can be firmly connected. In addition, the same effects as those of the second aspect are obtained.

According to the fourth aspect of the present invention, the coupling reinforcing portion is
Because it consists of multiple stud members fixed to the dowel,
The plurality of stud members are engaged with the solidified concrete, so that the relative movement of the dowel with respect to the concrete is restricted, and the concrete and the dovetail can be firmly connected. In addition, the same effects as those of the second aspect are obtained.

According to the fifth aspect of the present invention, the coupling strengthening portion is
Since it is composed of a plurality of corrugated protrusions, the corrugated protrusions engage with the solidified concrete, so that the relative movement of the dowel to the concrete is restricted, and the concrete and the dovetail can be firmly connected. In addition, the same effects as those of the second aspect are obtained.

According to the sixth aspect of the present invention, since the tubular body is a steel pipe, two concrete-filled steel pipes can be connected via a concrete and a dowel fixed to at least one concrete-filled steel pipe. In addition, the same effect as any of the first to fifth aspects of the invention can be obtained.

According to the seventh aspect of the present invention, since the guide portion serving as a guide when the other cylindrical body is externally fitted to the end of the projecting portion of each dowel is formed, the other cylindrical member is attached to each dovetail. Can be easily fitted to the outside, and the number of connection work can be reduced. In addition, the same effect as any of the first to sixth aspects of the invention can be obtained.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a joint structure (before connection) of a concrete-filled steel pipe according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

Fig. 3 Joint structure of concrete filled steel pipe (connected state)
FIG.

FIG. 4 is a sectional view taken along line IV-IV of FIG. 3;

FIG. 5 is an enlarged view of a main part of FIG. 3;

FIG. 6 is a partially enlarged sectional view of a first modification.

FIG. 7 is a diagram corresponding to FIG. 3 of a modification 2;

FIG. 8 is a diagram corresponding to FIG. 3 of a modification 3;

FIG. 9 is a diagram corresponding to FIG. 4 of a modification 4;

FIG. 10 is a longitudinal sectional view of a conventional joint structure (connected state of different diameter pipes).

FIG. 11 is a longitudinal sectional view of a conventional joint structure (the same diameter pipe connection state).

[Explanation of symbols]

 Reference Signs List 1 concrete-filled steel pipe 1D concrete-filled tubular body 2 steel pipe 2D tubular body 3 concrete 4,4A, 4B, 4C, 4D joint structure 10,10B shaft center 11,11A, 11B, 11C, 11D dowel 12,12C protrusion 13 Concrete filling hole 20 Stud member 21 Corrugated protrusion 22 Guide part

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Osamu Kawabata 8 Harima-machi, Harima-cho, Kako-gun, Hyogo Prefecture Inside the Harima Plant of Kawasaki Heavy Industries, Ltd. 2D059 AA03 AA05 BB39 GG55 2E125 AA48 AB13 AC01 AC16 AG03 AG25 BA02 BB02 BD01 BE07 BF03 CA82

Claims (7)

[Claims] 1. A joint structure for connecting ends of two metal cylindrical bodies via concrete filled in the cylindrical bodies, wherein at least one of the cylindrical bodies has an inner end. A plurality of dowels projecting outward in the axial direction are fixed to the portion, and the protruding portions of the dowels are inserted into the other cylindrical body,
A joint structure of a concrete-filled tubular body, characterized in that these dowels are joined to the other tubular body by concrete, and ends of the two tubular bodies are connected to each other through the plurality of dowels and concrete. . 2. The joint structure for a concrete-filled cylindrical body according to claim 1, wherein each of the dowels is provided with a connection reinforcing portion for reinforcing the connection between the concrete and the dovetail. 3. The joint structure for a concrete-filled cylindrical body according to claim 2, wherein the connection reinforcing portion includes a plurality of concrete-filled holes. 4. The connection strengthening portion comprises a plurality of stud members fixed to a dowel.
The joint structure of the concrete-filled cylindrical body according to the above. 5. The joint structure for a concrete-filled tubular body according to claim 2, wherein the connection strengthening portion comprises a plurality of corrugated protrusions. 6. The joint structure for a concrete-filled tubular body according to claim 1, wherein said tubular body is a steel pipe. 7. The guide according to claim 1, wherein a guide portion serving as a guide when the other cylindrical body is externally fitted to an end of the projecting portion of each of the dowels is formed. Concrete-filled tubular joint structure.