JP2000017731A - Joint structure of concrete member to steel pipe member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a joint structure of a concrete member to a steel pipe member excellent in fatigue-proof with a simplified structure and having no structural weak point. SOLUTION: A part of the bar steel material 23 is inserted into a steel pipe member from the end of a steel pipe 21 and the end is screwed into a nut 27 fixed through a steel plate material 24. The interior of the part of the steel pipe 21 where the bar steel material 23 is inserted into is formed with a plurality of protrusions distributed in approximately an uniform manner. A filler 26 is filled into the steel pipe 21 so as to envelop the bar steel material 23 and to stick to the internal surface of the steel pipe 21. The filler 26, which hardens and sticks to the bar steel material 23 and the internal surface of the steel pipe 21, transfers tensile force actuating on the steel pipe 21 to the bar steel material 23 by its adhesive strength. The other end of the bar steel material 23 is embedded and anchored into a concrete member 11 formed so that the end of the steel pipe 21 comes into collision with it.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for joining steel pipe members and concrete members in civil engineering or building structures.

[0002]

2. Description of the Related Art Concrete or steel is widely used as a structural material for civil engineering or building structures. Concrete has an advantage that a member of an arbitrary shape can be formed at a construction site and maintenance is easy, and a steel material has an advantage that a lightweight and strong structure can be constructed. And concrete / steel composite structure has been proposed as a structure taking advantage of each of the above advantages, for example,
There is a concrete / steel composite truss bridge in which the upper deck and the lower deck of road bridges and railway bridges are made of concrete, and these are connected by steel pipe diagonal members.

[0003] In such a structure, it is necessary to smoothly transmit the force at the joint between the concrete member and the steel member, to suppress the generation of large local stress, and not to cause a structural weakness. As such a joint structure between a concrete member and a steel member, for example, in a concrete / steel composite truss bridge, the upper chord, the lower chord and the diagonal of the truss are integrally assembled by a steel member, and the stud dowel is attached to the upper chord and the lower chord. A structure has been considered in which an upper floor and a lower floor made of concrete are integrated with each other. However, in such a structure, a large amount of steel is used, the construction cost becomes large, and high precision is required for assembling the steel truss, so that advantages of a composite structure of concrete and steel members cannot be utilized. .

For this reason, it is desirable to adopt a structure in which each of the steel diagonal members is directly joined to the upper slab or the lower slab of concrete, and the following joining structures have been considered. In the joint structure shown in FIG. 10, a steel plate 102 is welded to an end of a steel member 101, which is a diagonal member, substantially perpendicularly to the axis of the member.
A plurality of stud dowels 103 are erected from this steel plate.
Then, concrete is cast so as to embed the stud dowel 103 to form a concrete member 104 integrally joined with the steel member 101. Further, in the joining structure shown in FIG. 11, a steel plate 112 is welded to the end of a steel member 111 in the same manner as in the example shown in FIG.
A bar-shaped steel material 113 such as a PC steel rod or a steel bar is screwed into the screw hole formed in Step 2. By embedding this PC steel bar or steel bar in concrete, concrete member 1
14 and the steel member 111 are integrated.

[0005]

However, FIG.
Alternatively, the joining structure as shown in FIG. 11 has the following problems. In the structure as shown in FIG. 10, the force acting on the steel member 101 is transmitted to the concrete member 1 via the steel plate 102 at the end and the stud dowel 103 welded thereto.
04. Therefore, the steel member 101 and the steel plate 10
2 and the weld between the steel plate 102 and the stud dowel 103 are required to have sufficient strength and reliability, and it is necessary to strictly control and inspect the welding process. In addition, it is difficult to use a high-strength steel material for the stud dowel 103 to be welded and joined, and the number of necessary stud dowels may increase, which may make the arrangement difficult. Further, in a composite truss bridge or the like, a force that fluctuates repeatedly acts on the joint between the concrete member and the steel member, and the weld joint between the steel member 101 and the steel plate 102 and the stud dowel 103
May cause fatigue fracture.

On the other hand, in the structure shown in FIG. 11, a high-strength steel such as a PC steel bar can be used as the bar-shaped steel material 113, and the number of bars can be reduced to simplify the structure of the joint. However, when a thread is provided on the bar-shaped steel material and a large axial force or bending moment repeatedly acts on the joint between the concrete member 114 and the steel member 111, the bar-shaped steel material 113 is formed at the portion where the thread is provided. It is possible that fatigue fracture occurs. Further, similarly to the structure shown in FIG. 10, there is a possibility that fatigue fracture may occur at the welded joint between the steel member 111 and the steel plate 112.

The invention according to the present application has been made in view of the above-mentioned problems, and an object thereof is to provide a concrete member and a steel pipe member having a simple structure, excellent fatigue resistance, and having no structural weakness. Is to provide a bonding structure.

[0008]

In order to solve the above-mentioned problems, the invention according to claim 1 is characterized in that a part of a bar-shaped steel material is inserted into the steel pipe member from an end of the steel pipe member,
A projection is formed on an inner surface of a portion of the steel pipe member into which the bar-shaped steel material is inserted, and inside the vicinity of an end of the steel pipe member, the bar-shaped steel material is wrapped and hardened to harden the bar-shaped steel material and the steel pipe member. A filler member is filled, a concrete member is formed such that an end of the steel pipe member is brought into contact with concrete, and a portion of the bar-shaped steel material protruding from the end of the steel pipe member is embedded in the concrete member. The present invention provides a joint structure between a concrete member and a steel pipe member.

[0009] In the above structure, the bar-shaped steel material is a reinforcing steel or P
C steel or the like can be used, and in order to smoothly transmit the force due to the adhesion with the concrete or the filler, it is preferable to use a deformed reinforcing steel bar or a deformed PC steel rod having irregularities provided almost uniformly on the peripheral surface. desirable. The protrusion formed on the inner surface of the steel pipe member may be any one that is firmly joined to the steel pipe member, and each one may be an independent mountain-shaped, linear, or annular one, or a steel pipe member. Various forms, such as an annular shape or a spiral shape continuous in the circumferential direction of the inner surface of the member, can be adopted. It is desirable that the projections be formed by welding beats as described in claim 2. However, the projections may be formed by adding a billet, a bar, a wire, or the like by welding or the like. It may be provided sometimes. In addition,
According to the configuration of the second aspect, the projections can be efficiently formed, and the projections formed of the formed weld beads are firmly integrated with the steel pipe.

[0010] The filler is in contact with the inner surface of the steel pipe member and the projections provided on the inner surface, and can be filled so as to wrap the rod-shaped steel material inserted inside the steel pipe member. Various materials can be used as long as they strongly adhere to steel, such as concrete, mortar, cement grout,
There are synthetic resins such as epoxy, resin concrete, resin mortar, and the like. In addition, in the case of a cement-based material, it is desirable to use a mixture of an admixture for suppressing shrinkage during curing or aluminum powder.

In the joint structure between the concrete member and the steel member having such a configuration, the compressive force acting on the steel tube member is transmitted to the concrete member struck from the end of the steel tube member. Further, the tensile force is transmitted to the filler once by the adhesive force with the filler inside the steel pipe member, and further transmitted to the bar-shaped steel material. Since the rod-shaped steel material has a portion protruding from the end of the steel pipe member embedded in the concrete member, a tensile force is transmitted to the concrete member via the rod-shaped steel material. As described above, since the tensile force is transmitted by the adhesive force that acts by distributing over a wide range of the peripheral surface of the rod-shaped steel material, stress is less concentrated locally, and the fluctuating axial force and bending moment are prolonged. In the case of acting repeatedly over a long period of time, there is no possibility that fatigue fracture will occur in the bar-shaped steel material. Further, in the above-described joint structure, it is not necessary to use a weld joint in a portion where a large force acts, and it is possible to eliminate structural weakness.

On the other hand, since the plurality of projections are formed substantially evenly on the inner surface of the steel pipe member, the adhesion performance between the steel pipe member and the filler is enhanced, and the adhesive force of the filler is reduced or lost. Also, the consolidated body of the filler is restrained so as not to escape from the steel pipe member. For this reason, the tensile force can be more reliably transmitted to the concrete member, and a joint structure excellent in reliability and fatigue resistance can be obtained.

Further, the end portion of the steel pipe member does not need to be provided with many stud dowels or the like, and can have a simple structure. The occurrence of defects can be reduced.

According to a third aspect of the present invention, a part of a rod-shaped steel material is inserted into the steel pipe member from an end of the steel pipe member, and the tip of the rod-shaped steel material inserted into the steel pipe member is formed by A steel plate member joined to the steel pipe member so as to close the hollow portion and is disposed substantially perpendicular to the axis of the steel pipe member,
The steel pipe member is locked so as to restrain the relative displacement, and the steel pipe member is filled with a filler material that wraps around the bar-shaped steel material and hardens and adheres to the bar-shaped steel material and the steel pipe member. A concrete member is formed such that an end of the steel member is abutted against concrete, and a portion of the bar-shaped steel material protruding from an end of the steel pipe member is embedded in the concrete member. It is to provide a joint structure with a member.

[0015] The above-mentioned steel sheet material is mounted so that when the hollow portion in the steel pipe member is filled with the uncured filler, there is no gap so as not to cause leakage. In addition, the joining with the steel pipe member does not necessarily need to be joined over the entire circumference, and it is sufficient that the position of the bar-shaped steel material is maintained and fixed so that the uncured filler can be supported,
For example, when welding is adopted, it may be joined at several places in the circumferential direction. In addition, the locking structure between the tip of the bar-shaped steel material and the steel plate material can be appropriately selected,
It is desirable that the bar-shaped steel material inserted from the end of the steel pipe be easily locked after the steel sheet material is joined into the steel pipe.

In the joining structure having such a configuration, the tip end of the portion of the bar-shaped steel material inserted into the steel pipe member is locked to the steel plate material, the transmission path of the force in the fixing mechanism is dispersed, and the joining portion is further reduced. Reliability can be improved.
Further, the rod-shaped steel material inserted into the steel pipe is held at a predetermined position to easily inject the filler, and the steel plate functions as a mold for the filler, thereby improving the work efficiency.

According to a fourth aspect of the present invention, in the joint structure between a concrete member and a steel pipe member according to any one of the first to third aspects, an axis of the steel pipe member is provided at an end of the steel pipe member. And the end steel plate is joined almost at right angles,
It is assumed that the rod-shaped steel material is inserted into the steel pipe member through an opening provided in the end steel plate.

The steel pipe member and the end steel plate may be joined by a conventionally known general method such as welding.
The opening provided in the end steel plate is desirably slightly larger than the rod-shaped steel material inserted therethrough, but it may be provided with a large opening through which a plurality of rod-shaped steel materials can be inserted. In addition, the bar-shaped steel material and the end steel plate are not engaged with each other, so that no force is transmitted.

In the joint structure having such a configuration, even when the adhesion between the steel pipe member and the filler is impaired, the solidified body of the filler integrated with the rod-shaped steel material abuts against the end steel plate,
The filler does not escape from the steel pipe member. For this reason,
The tensile force is reliably transmitted from the steel pipe member to the rod-shaped member, and high reliability of the joint is obtained. Further, in the above-mentioned joint structure, the compressive force is transmitted to the concrete via the steel plate at the end, thereby avoiding locally generating a large stress in the concrete.

According to a fifth aspect of the present invention, in the joint structure between a concrete member and a steel pipe member according to the fourth aspect,
An insertion member that is more flexibly deformed than the hardened filler is bonded to the center portion of the steel pipe member on the surface of the end steel sheet joined to the steel pipe member, and the hardened filler and the end steel sheet are bonded together. It shall be isolated near the center of the steel pipe.

As in the above joint structure, when a rod-shaped steel material is inserted into a steel pipe member and the steel pipe member and the rod-shaped steel material are integrated by a hardened filler, the steel pipe member and the concrete member are separated from each other. When a force is applied, the filler hardened by the tensile force of the bar-shaped steel material is deformed. That is, shear deformation occurs between the peripheral portion of the rod-shaped steel material and the portion adhered to the inner surface of the steel pipe member. And
When the filler is filled so as to be in close contact with the end steel plate, the hardened filler is pressed strongly against the end steel plate, and as shown in FIG. A large bending moment occurs at the joint. When such a bending moment acts repeatedly, there is a possibility that fatigue fracture may occur in a welded joint between the end steel plate and the steel pipe member. Although this portion does not cause a structural problem immediately even if it is broken, it causes deterioration of durability and the like.
However, since the interposition member is adhered to the end steel plate as in the joint structure according to claim 5, the deformation of the filler when a large tensile force acts on the bar-shaped steel material is reduced by the insertion member. And the bending moment acting on the end steel plate is reduced.

It is preferable that the interposition member is not adhered to the entire inner surface of the steel pipe member, but is formed only at the center portion so that the filler directly contacts the end steel plate at the periphery. Since the filler is in contact with the end steel plate at the peripheral portion in this manner, even when the adhesion between the hardened filler and the steel pipe member is broken, the relative displacement between the filler and the steel pipe member is restricted. Will be.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic side view and a sectional view showing a concrete / steel composite truss bridge to which a joint structure between a concrete member and a steel pipe member according to an embodiment of the present invention is applied. This composite truss bridge has a continuous truss 2 supported on a plurality of piers 1a and 1b and an abutment (not shown). The truss structure includes an upper deck 11 made of prestressed concrete and The main part is composed of a lower floor slab 12 of prestressed concrete supported by a slab, and a steel pipe diagonal member 13 connecting the upper floor slab 11 and the lower floor slab 12, and the upper floor slab 11 is used as an upper chord material, Reference numeral 12 functions as a lower chord material.

The upper floor slab 11 is continuous in the axial direction of the bridge, on which a road surface is formed, and a PC steel material (not shown) is buried in the axial direction and at right angles thereto. Prestress is introduced by tensioning these PC steel materials and fixing them to concrete, so that even when a compressive force or a tensile force due to functioning as the upper chord material acts, harmful cracks and the like do not occur. It has become. On the other hand, the prestress is also introduced into the lower floor slab 12 in the axial direction of the bridge, so that the lower slab 12 can withstand the compressive and tensile forces caused by functioning as the lower chord of the truss. The diagonal members 13 are arranged so as to be inclined in the axial direction of the bridge, and the diagonal members 13a and 13b whose inclination directions are reversed.
Are alternately arranged to form a warren truss. Each of the diagonal members 13a and 13b has an end portion on the upper floor slab 11.
And the lower deck 12.

FIG. 2 shows a joint between the concrete upper slab 11 and the diagonal member made of steel pipe in the concrete / steel composite truss bridge. It is sectional drawing which shows a joining structure. In this joint structure, an end steel plate 22 is welded to an end of a steel pipe 21 forming a main part of the diagonal member 13a at a right angle to an axis of the steel pipe, and the end steel plate 22 is connected to the concrete of the upper floor slab 11 by a concrete method. To transmit the compressive force. FIG. 3 is a view showing the end steel plate 22, that is, a view taken along the line AA shown in FIG. 2, and the end steel plate 22 is provided with a plurality of openings 22a communicating with the inside of the steel pipe. A part of the PC steel bar 23 is inserted into the steel pipe through these openings 22a. The PC steel rod 23 is embedded in the steel pipe, and is filled with expandable mortar so as to be in close contact with the inner peripheral surface of the steel pipe. The hardened expandable mortar 26 separates the PC steel rod 23 from the steel pipe 21. It is integrated. Therefore, the expandable mortar 26 from the steel pipe 21,
The tensile force is transmitted via the PC steel bar 23 to the upper slab 11 of concrete in which the other end of the PC steel bar 23 is embedded.

The PC steel bar 23 is a deformed steel bar in which a convex portion is provided substantially uniformly on the peripheral surface over the entire length, and the convex portion is provided in a spiral shape. The helical projection has an effect of increasing the adhesive force with the expandable mortar 26 as the filler, and also has a function as a screw thread that is screwed into the nut and locked.

As shown in FIG. 4, a steel plate 24 is welded to the inside of the steel pipe 21 near the tip of the inserted PC steel rod 23 at right angles to the axis of the steel pipe. The steel plate material 24 is formed by joining several places in the circumferential direction in the steel pipe so as to support the unhardened expansive mortar 26 injected into the steel pipe. The steel plate 24 is provided with the same number of circular holes as the number of PC steel rods to be inserted, and a nut 25 is welded to the back side of the circular hole, that is, on the side opposite to the end where the PC steel rod is inserted. Have been. The tip of the PC steel rod 23 inserted into the steel pipe 21 is screwed to the nut 25 and is locked to the steel plate 24 via the nut 25. Note that the length of the PC steel bar 23 protruding into the steel pipe 21 is determined so that the adhesive force between the expandable mortar 26 and the PC steel bar 23 exceeds the tensile strength of the PC steel bar.

As shown in FIG. 5A, a helical projection 21a is formed on the inner surface of the steel pipe 21 where the PC steel material 23 is inserted. This projection 21a
As shown in FIG. 5B, the inner surface of the steel pipe 21 has a height of about 3 m.
It is formed by applying bead welding of m or more continuously in a spiral shape at a pitch of about 30 mm. Note that the projection is not limited to a spiral one as shown in FIG. 5, and various shapes can be adopted. Even if the circumferential projection is formed in a plurality of stages, Alternatively, a plurality of mountain-shaped protrusions 21b as shown in FIG. 6 may be formed so as to be distributed substantially uniformly.

The expandable mortar 26 is filled in a portion of the steel pipe 21 sandwiched between the end steel plate 22 and the steel plate 24 using the steel plate 24 as a mold. In addition, it is mixed with an admixture which causes expansion, has high fluidity at the time of injection, and is filled around the projections 21a on the inner surface of the steel pipe 21 and the PC steel rod 23 without gaps.
The expandable mortar 26 is hardened and strongly adheres to the PC steel rod 23 and the inner surface of the steel pipe 21. The adhesive force causes the PC steel rod 23, the expandable mortar 26, and the steel pipe 2.
1 and the tensile force acting on the diagonal member 13 made of the steel pipe 21 is transmitted to the upper slab 11 made of concrete via the expandable mortar 24 and the PC steel bar 23.

As shown in FIG. 7, a urethane foam disk 29 (interposed member) is provided at the center of the inner side of the end steel plate 22.
At the peripheral portion in the steel pipe 21, the expandable mortar 26 is in direct contact with the end steel plate 22, but at the center, the expandable mortar 26 and the end steel plate are formed by the urethane foam disk 29. 22 are isolated.

The above-mentioned urethane foam disk 29 closes the gap between the PC steel bar 23 and the end steel plate 22 at the time of filling the expandable mortar, thereby preventing leakage of the expandable mortar. Even if the expandable mortar 26 is deformed so as to expand outward by the tensile force of the PC steel rod 23, the end
No large bending moment is generated.
Note that, instead of the urethane foam disk 29, a member made of another material can be used, and a rubber, a foamed resin, or the like, which deforms more flexibly than the cured expandable mortar, can be used.

In the warren truss as shown in FIG. 1, the diagonal members made of the above-mentioned steel pipes are provided adjacent to each other in such a manner that the inclination direction is reversed. Is a diagonal member 13b to which a compressive force mainly acts. In the diagonal member 13a to which the tensile force mainly acts, the end steel plate 2
2, PC steel rods 23 projecting outward from the openings provided in 2 and embedded in the concrete forming upper floor slab 11.
In order to supplement the adhesive force between the PC steel bar 23 and the concrete, a nut 27 is screwed into the end of the PC steel material. An anchor plate 28 is locked. In addition, also about the diagonal member 13b to which a compressive force mainly acts, the end steel plate 32 welded to the steel pipe 31, the PC steel rod 33 inserted into the steel pipe from the opening provided in the end steel plate 32, Steel plate material 34 and nut 3 to which PC steel bar 33 is locked
5. The expandable mortar 26 filled in the steel pipe 31 has the same configuration, but is different from the diagonal member 13a on which the tensile force mainly acts, in which the anchor plate and the The nut is not locked.

On the other hand, the joint between the diagonal member made of the steel pipe and the lower slab, that is, the lower end of the steel pipe has the same structure. The PC steel rod inserted in the inside and the expansive mortar filled in the steel pipe so as to embed the PC steel rod, the tensile force between the diagonal member 13 made of the steel pipe and the concrete forming the lower slab 12 and Joined to transmit compressive force.

In such a concrete / steel composite truss bridge, the diagonal members 13a, 13b are provided between the upper slab 11 and the diagonal members 13a, 13b and between the lower slab 12 and the diagonal members 13a, 13b.
The force in the axial direction of 13b is reliably transmitted, and the warren truss can support its own weight and the applied load. And
In such a structure, there is a diagonal member in which a greatly fluctuating force repeatedly acts due to a fluctuating load (live load) of a vehicle or the like passing over a bridge. Stress concentration is less likely to occur at the joint with the floor slab 12, and fatigue fracture can be prevented.

That is, the tensile force transmitted from the steel pipe 21 to the upper slab 11 and the lower slab 12 of the concrete is caused by the adhesive force distributed over a wide area of the peripheral surface of the PC steel bar 23 via the expandable mortar 26. The stress is transmitted to the PC steel bar 23 and a large stress is not locally generated in the PC steel bar. Therefore, P
The reliability with respect to the fatigue resistance of the C steel bar 23 is significantly improved.

The expandable mortar 26 is integrated with the steel pipe 21 by the adhesive force to the inner surface of the steel pipe. Further, the protrusion 21a provided on the inner surface of the steel pipe 21 allows the expandability mortar 26 to adhere to the expandable mortar 26. And the tensile force is transmitted without applying a large load to the welded joint at the end of the steel pipe.

Further, since the tip of the PC steel rod 23 inserted into the steel pipe 21 is locked to the steel plate material 24, the adhesive force between the PC steel rod 23 and the expandable mortar 26 can be supplemented. That is, even if the adhesive force between the PC steel bar 23 and the expandable mortar 26 is lost, the steel plate 24 and the nut 25 locked on the PC steel bar 23 abut on the expandable mortar 26 and the PC steel bar 23 Never escape. This maintains the double safety of the joints,
Durability is increased.

Furthermore, an end steel plate 22 is joined to the end of the steel pipe 21 at right angles to the axis, so that even if the adhesion between the steel pipe 21 and the expandable mortar 26 is impaired, the peripheral part of the expandable mortar 26 That is, the outside of the portion where the urethane foam disk 29 is inserted abuts against the end steel plate 22, and the expansible mortar 26 does not fall out of the steel pipe 21. For this reason, even between the steel pipe 21 and the consolidated body of the expandable mortar 26, double safety is secured, and high reliability of the joint is maintained.

Next, an example of a method of applying the above-mentioned joint structure will be described. First, the steel plate material 24 is joined to a predetermined position inside the steel pipe 21 by welding. In this welding, the disk-shaped steel sheet material 24 is held at a predetermined position, a welder is inserted into the steel pipe, and several points around the steel sheet material are joined to the inner surface of the steel pipe. A nut 25 is previously attached to the steel plate member 24 by welding. After the steel plate material 24 is mounted, continuous spiral bead welding is performed at a predetermined pitch (for example, a pitch of approximately 30 mm) on the inner surface of the steel pipe on the end side from the mounting position of the steel plate material 24. In this bead welding, a welder is inserted from an end of a steel pipe, and a weld bead is formed while rotating the steel pipe. After the projection by the welding bead is thus provided, the end steel plate 22 is joined to the end of the steel pipe by fillet welding.

The steel pipes 21, 31 thus processed
The PC steel rods 23, 33
And screwed and fixed to a nut 25 welded to the steel plate material 24. In such a state, the steel pipes 21, 3
An expandable mortar is filled between the steel plates 24, 34 and the end steel plates 22, 32 in 1 and hardened so that the PC steel bars 23, 33 in the steel pipes 21, 31 are embedded. Thereby, the PC steel rods 23 and 33 and the steel pipes 21 and 31 are integrated.

The steel pipes 21 and 31 thus filled with the expansive mortar are transported to a bridge erection position and supported at a predetermined position. Then, as shown in FIG. 8A, a formwork 41 for casting concrete of the upper slab and the lower slab to be joined to the steel pipe is assembled. A reinforcing bar 42 of a floor slab, a joint reinforcing bar 43, and the like are arranged in the formwork 41, and unhardened concrete is in close contact with the outside of the end steel plates 22, 32, and PC steel protruding from the end steel plates. Stick 2
Concrete is poured so as to embed 3, 33, and the upper floor slab 11 of concrete is formed.

In this embodiment, as described above, the PC
Expansive mortar is used to integrate the steel materials 23, 33 and the steel pipes 21, 31. Cement-based grout material, non-shrink concrete, resin Concrete or the like can also be used.

The work of filling the expandable mortar, installing the steel pipe in a predetermined position, arranging PC steel rods and reinforcing bars, and placing concrete is performed in a production yard near the bridge erection position. It is also possible to adopt a construction method in which a girder is manufactured as a plurality of divided blocks, which are joined on a pier and assembled.

As described above, in the joint structure of the concrete member and the steel pipe member according to the present embodiment, the work of welding the steel material on site can be omitted by processing the joint portion of the steel tube in advance at the factory, and the site can be omitted. Steps can be reduced. In addition, since the steel pipes are individually carried into the site one by one and are set up at the site so as to be set up at the site, high production accuracy at the factory is not required, and the construction management becomes easy.

[0045]

As described above, in the joint structure of a concrete member and a steel pipe member according to the present invention, the rod-shaped steel material transmitting the tensile force from the steel pipe member to the concrete member is filled with filler material interposed between the steel pipe member and the steel pipe member. By this, it is integrated with the steel pipe member. For this reason, the force is transmitted by the adhesive force distributed and applied from the filler to a wide range of the peripheral surface of the bar-shaped steel material, and stress concentration does not occur in the bar-shaped steel material, and the fatigue resistance is improved. In addition, the plurality of protrusions provided on the inner surface of the steel pipe member enhance the adhesion between the steel pipe member and the filler. On the other hand, even if the adhesion between the filler and the rod-shaped steel material, or the adhesion between the filler and the steel pipe member is impaired, the steel plate locked to the rod-shaped steel material and the end steel plate welded to the steel pipe member are used to reduce the filling material. The relative displacement between the solidified body and the bar-shaped steel material or between the solidified body of the filler and the steel pipe member is restrained, and the tensile force acting on the steel pipe is reliably transmitted to the bar-shaped steel material. For this reason, the joining portion has a double safety, and has a structure excellent in reliability and durability.

[Brief description of the drawings]

FIG. 1 is a schematic side view and a sectional view of a concrete / steel composite truss bridge to which a joint structure between a concrete member and a steel pipe member according to an embodiment of the present invention is applied.

FIG. 2 shows a joint structure between a diagonal member and an upper slab or a lower slab in the concrete / steel composite truss bridge shown in FIG. 1, and shows a joint structure between a concrete member and a steel pipe member according to an embodiment of the present invention. FIG.

FIG. 3 is an end view of a steel pipe used in the joining structure shown in FIG. 2;

FIG. 4 is a cross-sectional view showing a steel plate material attached inside a steel pipe used in the joining structure shown in FIG. 2;

FIG. 5 is a sectional view showing a projection provided at an end of a steel pipe used in the joining structure shown in FIG. 2;

FIG. 6 is a cross-sectional view showing another example of the projection provided on the inner surface of the end of the steel pipe.

FIG. 7 is a sectional view showing a structure of an end portion of a steel pipe.

8 is a schematic cross-sectional view showing a state during construction of the joining structure shown in FIG.

FIG. 9 is a diagram showing a bending moment generated in an end steel plate.

FIG. 10 is a schematic cross-sectional view showing an example of a conventionally known joint structure between a concrete member and a steel pipe member.

FIG. 11 is a schematic sectional view showing another example of a conventionally known joining structure between a concrete member and a steel pipe member.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Bridge pier 2 Truss 11 Upper floor slab 12 Lower floor slab 13 Diagonal material 21, 31 Steel pipe 21a Projection 22, 32 End steel plate 23, 33 PC steel material 24, 34 Steel plate material 25, 35 Nut 26, 36 Expansive mortar 27 Nut 28 Anchor Plate 29 Urethane foam disk (insertion member) 41 Formwork 42 Reinforcing bar 43 Joint reinforcement

Continuing from the front page (72) Inventor Atsushi Nagai 4-13 Arakicho, Shinjuku-ku, Tokyo Sumitomo Construction Co., Ltd. (72) Inventor Satoru Sugimura 13-4 Arakicho, Shinjuku-ku, Tokyo Sumitomo Construction Co., Ltd. (72 ) Inventor Daisuke Takeuchi 4-5-33 Kitahama, Chuo-ku, Osaka-shi, Osaka Sumitomo Metal Industries, Ltd. (72) Inventor Nobuo Hatano 4-5-33, Kitahama, Chuo-ku, Osaka-shi, Osaka Sumitomo Metal Industries, Ltd. F term (reference) 2E163 FA02 FB06 FB43 FD43 FD48 FF17

Claims (5)

[Claims] 1. A part of a rod-shaped steel material is inserted into an end of a steel pipe member from the end of the steel pipe member, and a projection is formed on an inner surface of a portion of the steel pipe member into which the rod-shaped steel material is inserted. Inside the vicinity of the end of the member, the rod-shaped steel material is wrapped and filled with a filler material which is hardened and adheres to the rod-shaped steel material and the steel pipe member, and the concrete is placed so that the end of the steel pipe member is pressed against the concrete. A joint structure between a concrete member and a steel pipe member, wherein a member is formed, and a portion of the rod-shaped steel material protruding from an end of the steel pipe member is embedded in the concrete member. 2. The joint structure between a concrete member and a steel pipe member according to claim 1, wherein the projection is formed by a weld bead. 3. A part of a rod-shaped steel material is inserted from an end of the steel pipe member into the steel pipe member, and a tip of the rod-shaped steel material inserted into the steel pipe member is substantially perpendicular to an axis of the steel pipe member. Is fixed to a steel plate member joined to the steel pipe member so as to close the hollow portion so as to restrict the relative displacement, and the rod-shaped steel material is wrapped around the inside of the vicinity of the end of the steel pipe member and hardened. A filler is attached to the rod-shaped steel material and the steel pipe member, and a concrete member is formed such that an end of the steel pipe member is abutted against concrete, and protrudes from the steel pipe member end of the rod-shaped steel material. A joint structure between a concrete member and a steel pipe member, wherein a portion is embedded in the concrete member. 4. An end steel plate is joined to an end of the steel pipe member substantially at right angles to an axis of the steel pipe member, and the rod-shaped steel material is inserted into an opening provided in the end steel plate, The joint structure between a concrete member and a steel pipe member according to claim 1, wherein the concrete member is inserted into the steel pipe member. 5. An interposed member which is more flexible than the hardened filler is adhered to a center portion of the steel plate member on a surface of the end steel plate joined to the steel pipe member, and the hardened filler and the end are bonded. The joint structure between a concrete member and a steel pipe member according to claim 4, wherein the steel plate part is isolated near a central portion in the steel pipe.