KR101746547B1 - Composite steel pipe girder and the bridge thereof - Google Patents

Abstract

The present invention relates to a structure of a girder installed at a lower portion of a top plate for supporting a load of a bridge while transmitting it to a fulcrum portion such as an alternate bridge or a pier, and the girder structure includes a girder portion, Wherein the girder portion comprises a steel box girder portion alternately or at a pier and a circular steel pipe girder portion placed in a transversal portion between alternate or pierced angles, A supporting beam is provided between the steel pipe girder and the deck plate so that the load acting on the deck plate is transmitted to the circular steel pipe girder through the support beam. In the portion where the support beam is not provided, air And a support beam is installed to form a flow portion.

Description

TECHNICAL FIELD [0001] The present invention relates to a composite steel pipe girder structure and a bridge using the composite steel pipe girder structure.

The present invention relates to a structure of a girder installed at a lower portion of a top plate for supporting a load of a bridge while transmitting it to a fulcrum portion such as an alternate bridge or a pier. More specifically, the present invention relates to a structure of a girder, The present invention relates to a structure of a composite steel pipe girder having a structure that can be efficiently maintained and easily maintained.

Generally, a steel structure is lightweight compared to a concrete structure, has a large tensile strength, can secure homogeneity of a material, can shorten a construction period, and is widely used in large bridges.

Among these bridges, the box type girder is advantageous to twist deformation and is widely applied to curved bridge. However, since the box girder has a large section of the girder, there is an uneconomical aspect due to an increase in the amount of steel used.

Another example of a steel structure bridge is the use of a circular steel pipe. The circular pipe steel girder bridge is one of the reasons that the girder is advantageous in improving the urban image because the cross section of the girder has a smooth appearance.

FIG. 10 shows an example of a girder bridge using the above-described circular steel pipe, which is disclosed in Registration No. 10-0933265.

As shown in Fig. 10, the steel pipe girder bridge includes a bridge top plate 10; A plurality of steel pipe girders (20) arranged on the lower side of the bridge upper plate (10) side by side in the longitudinal direction of the bridge upper plate (10); A cross beam 30 installed between the plurality of steel pipe girders 20 in the lateral direction of the bridge upper plate 10; Each of the steel pipe girders 20 supporting the bridge upper plate 10 includes a saddle 50 interposed between the steel pipe girder 20 and the lower structure 40 of the bridge supporting the steel pipe girder 20, A concrete filler 22 filled in the circular steel pipe 21 and at least one shear connector 22 for increasing the synthetic action between the concrete filler 22 and the circular steel pipe 21, (23). At this time, it is preferable that the concrete filler 22 is installed only on a portion of the lower structure to be supported.

The steel pipe girder bridges of the above-mentioned registration number 10-0933265 use round steel pipes 21 to improve the appearance and at the fulcrum parts, concrete is filled therein to greatly increase the rigidity of the girder ends which are insufficient only by the round steel pipes 21 So that the diameter of the round steel pipe 21 can be kept constant.

However, when the concrete is filled in the circular steel pipe as described above, the operator can not access the inside of the circular steel pipe, so that the maintenance of the circular steel pipe girder itself can not be performed completely.

In addition, the filling of concrete to the round steel pipe increases the cost of construction by adding extra material cost to concrete and putting equipment and manpower to pour it.

On the other hand, the girder bridges of steel structures have a great concern about corrosion due to the nature of their materials, and furthermore, where the bridges are installed, they are located in regions where there is a large amount of water or salinity such as valleys, rivers and oceans. Management is the biggest factor that determines the durability of bridges.

Therefore, it is necessary to carry out repainting in a constant cycle based on the lifetime of the bridge.

However, in the case of using a conventional round steel pipe including the registration No. 10-0933265 as a girder, the circular steel pipe is integrally welded to the deck plate for constituting the upper plate as shown in FIGS. 10 and 11. However, The corner portion (circular arc portion in FIG. 11) between the upper surfaces of the round steel pipes contacting with each other is very narrow, so that not only short ball striking phenomenon occurs during painting work but also occurrence of defects is frequent due to difficulty in painting, There is a problem that the durability is lowered.

KR 10-0933265 B1

The present invention has been made to solve the above problems of the conventional art, and it is an object of the present invention to at least partially solve the problems in the conventional technology, and to provide a method and apparatus for minimizing the amount of materials or members of steel, concrete, And a girder structure capable of increasing durability by facilitating maintenance of the girder even when the bridge is in use, and a bridge using the girder structure.

According to a most preferred embodiment of the present invention for solving the above problems, in a girder structure of a bridge composed of a girder portion and a deck plate provided on the upper portion of the girder portion, the girder portion includes a steel A box girder portion and a circular steel pipe girder portion placed in a transversal portion between alternate or pierced angles, and a support beam is provided between the deck plate and the circular steel pipe girder portion so that a load acting on the deck plate is transmitted through the support beam And a supporting beam is provided so that an air flow is formed between the deck plate and the circular steel pipe girder at a portion where the support beam is not installed.

At this time, a stress-stiffening material for stress dispersion may be provided at a lower portion of the round steel pipe at a portion where the steel box girder portion and the round steel pipe girder portion are in contact with each other. Without the rigid stiffener or the rigid stiffener, A T-type tensile stiffener may be provided. Further, a door may be further provided on the outer end or the lower surface of the steel box girder.

The present invention can provide a smooth and beautiful appearance of a curved section by varying the structure with respect to the span and the fulcrum portion, and can stably support the operating load without using a member such as a saddle and has a high torsional rigidity. To be applicable to bridges.

Further, according to the present invention, by using a non-box-shaped circular steel pipe continuous in the fulcrum portion, the width of the girder is reduced to reduce the amount of steel material while increasing the size of the mold, Not only the stress due to the wind load is dispersed but also an upward force is generated in the circular steel pipe girder portion according to the change of the air pressure caused by the air flow so that the bending stiffness of the girder portion is increased without any additional reinforcement, And the deck plate so as to prevent the occurrence of paint defects beforehand.

Also, since the reinforcing member such as concrete is not installed in the inside of the round steel pipe part, the worker can easily get in and out, and the door can be installed at the end of the girder part.

1 is a front view of a bridge to which a girder structure according to an embodiment of the present invention is applied.
2 is a front view and A '-A' sectional view for explaining the rigid stiffener of the present invention.
3 is a cross-sectional view of AA and BB in Fig. 1 for explaining the round steel pipe girder of the present invention.
Figs. 4 to 6 are a cross-sectional view, a front view, and a plan view showing respective embodiments of the T-type tensile stiffener of the present invention.
7 is a cross-sectional view illustrating a process of installing a T-type tensile stiffener so that a prestress is introduced into the round steel pipe girder of the present invention.
8 is a longitudinal and transverse sectional view of each embodiment in which a concrete member is provided on the inner surface of a steel box girder part of the present invention.
Figs. 9 and 10 are a front view, a side view, and a bottom view, respectively, of the respective embodiments showing a state in which a door is provided on the end portion of the steel box girder portion of the present invention.
11 is a sectional view of a circular steel pipe girder according to the prior art.
12 is a partial detail view showing a joint between a circular steel pipe and a deck plate of a round steel pipe girder according to another conventional technique.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, in order to obscure or obscure the technical idea of the present invention due to the detailed description of the known structure in describing the present invention, the description of the structure of the above known structure will be omitted.

1 is a front view of a bridge constructed by applying a girder structure according to an embodiment of the present invention.

The girder structure of the present invention comprises a girder portion 100 for supporting the load of the upper plate and a deck plate 200 installed on the upper portion of the girder portion 100 to construct the upper plate.

1, the girder part 100 has a structure of a composite steel pipe in which the structure of the steel box girder and the structure of the round steel pipe girder are combined to maximize the advantages of each structure. As shown in FIG. 1, (110) and a circular steel pipe girder (120).

The circular steel pipe girder 120 is formed of a round steel pipe 121 having a circular closed cross section and is placed at a shift part between alternate or pier angles so as to have a smooth image of the curve across the bridge, Reduce the size of your brother by reducing.

The steel box girder 110 is formed of a rectangular steel pipe having a closed cross section and is placed on a fulcrum portion 300 such as an alternate pier or a pier to securely transmit the upper load of the bridge and greatly increase the torsional rigidity But also solves the problem of a bridge composed of only the other round steel pipes 121.

For example, in the girder structure of the round steel pipe 121, a portion placed on the fiducial portion 300 may have a cross-sectional structure such as a large cross-section so as to correspond to the stress caused by the momentum, or a reinforcing material, The cross sectional structure of the electron makes it very difficult to manufacture the steel pipe and the latter reinforcing means makes it difficult for the worker to get in and out of the inside of the round steel pipe 121,

However, according to the present invention, since the steel box girder portion 110 having a rectangular cross section is formed with respect to the fulcrum portion 300, it is not necessary to change the steel pipe standard of the round steel pipe girder portion 120 located at the slender portion, So that the reinforcement means is not added to the inside of the girder portion 100, thereby ensuring the passage of the worker, thereby facilitating the post-management of the inside of the girder portion 100.

On the other hand, at a portion where the steel box girder portion 110 and the circular steel pipe girder portion 120 are in contact with each other, a stress concentration phenomenon may occur due to a change in cross section. For this purpose, a stiff stiffener 122 for stress distribution may be installed below the round steel pipe 121 at a portion where the steel box girder 110 and the round steel pipe girder 120 are in contact with each other. 2 is a front view and a sectional view taken along the line A'-A 'of the portion where the rigid stiffener 122 is installed.

3 is a cross-sectional view for explaining the installation structure of the round steel pipe girder 120 located at the transversal part.

The steel pipe of the circular steel pipe girder 120 is spaced apart from the deck plate 200 constituting the upper plate so that an air flow portion F is formed therebetween and a load acting on the deck plate 200 is transmitted to the support beams 130 To the circular steel pipe girder part 120 through a pipe (not shown).

A plurality of support beams 130 are provided between the deck plate 200 and the circular steel pipe girder 120 so as to be spaced apart from each other so that the load of the upper plate is transmitted to the fulcrum 300 The supporting beams 130 are spaced apart from the deck plate 200 and the circular steel pipe girder 120 as shown in FIG. 3 (b) Respectively.

This air flow portion F not only disperses wind loads such as typhoons but also increases the flow rate at the portion passing through the air flow portion F to decrease the pressure and generate an upward force on the circular steel pipe 121 So as to have an effect of increasing the flexural rigidity due to the upper load of the upper plate.

The gap between the deck plate 200 and the circular steel pipe girder portion 120 by the air flow portion F is larger than the distance between the upper surface of the circular steel pipe 121 constituting the circular steel pipe girder portion 120 and the upper surface of the deck plate 200), and thus it is possible to solve the problem of defective painting which has occurred in the conventional round steel pipe girders so far.

4 to 6 illustrate another embodiment of the present invention in which the outer surface of the circular steel pipe girder 120 is reinforced to increase the flexural rigidity.

In the present embodiment, a T-shaped tensile stiffener 123 composed of a flange 123a and a web 123b is provided below the round steel pipe girder 120. [

The T-type tensile stiffener 123 may have the same cross section with respect to the longitudinal direction. However, by providing a cross-section corresponding to the kind and size of the stress to be reinforced, the girder structure is optimized It is preferable to have a cross-section of the cross section.

As shown in FIG. 4, the T-type tensile stiffener 123 may be configured such that the width of the flange 123a gradually increases from the center toward both ends.

In this case, the T-shaped tensile reinforcement 123 located at the portion where the steel box girder 110 and the circular steel pipe girder 120 are in contact with each other reinforces the tensile rigidity of the circular steel pipe girder 120, The cross section prevents the stress concentration phenomenon between the steel box girder 110 and the circular steel pipe girder 120 so that stress transmission can be smoothly performed. Therefore, it is possible to omit the installation of the stiffness stiffener 122 for stress dispersion described above.

As shown in FIG. 5 in the second embodiment of the T-type tensile reinforcement 123, the width of the web 123b gradually increases from both ends to the center.

The T-type tensile stiffener 123 is installed on the circular steel pipe girder 120. In this case, it is possible to reinforce the beam with the optimum cross-section generated in the transversal portion, Thereby allowing the introduction of the prestress to the part 120. [

7 is a cross-sectional view illustrating a process of installing a T-type tensile stiffener 123 such that a prestress is introduced into the circular steel pipe girder 120 as described above.

This type of T-type tensile stiffener 123 is manufactured by: a) fabricating a T-type tensile stiffener 123 so as to correspond to a magnitude of a stress to be reinforced first and a degree of change, wherein the width of the web 123b is wide at the center, A T-shaped tensile stiffener 123 having a narrow shape at its end, a flange 123a having a straight shape with respect to the longitudinal direction, and a web 123b having an arcuate shape, and b) After the end face of the web 123b is brought into contact with the bottom face of the steel pipe of the round steel pipe girder portion 120 in a state where a load is applied to both ends of the T-shaped tensile stiffener 123, and c) And removing the load applied to both ends of the T-type tensile reinforcement 123.

The width of the flange 123a gradually widens from the center toward both ends, as shown in Figure 6 in a third embodiment for the T-type tensile stiffener 123, and the width of the web 123b is greater at both ends It is possible to achieve the object of pursuing both of the above-mentioned two embodiments by constituting a configuration that gradually widens toward the central portion.

The T-type tensile stiffener 123 in this embodiment can also be installed in a manner similar to that described in the second embodiment, so that the prestress can be introduced into the round steel pipe girder 120.

The steel box girder portion 110 placed on the fiducial portion 300 of the alternation and pier is transmitted to the fiducial portion 300 with all vertical loads acting on the girder, Stress is generated.

In order to cope with such a shear stress, a concrete member 111 may be further installed in the steel box girder 110. [

8 is a cross-sectional view showing each embodiment in which the concrete member 111 is provided on the inner surface of the steel box girder 110. Fig. 8A is a cross-sectional view of the concrete box 111, (B) is an example in which a concrete member 111 is installed in a manhole manner with respect to all the inner surfaces of the steel box girder 110. FIG.

The steel box girder 110 may further include a door 112 for efficient maintenance of the bridge. 9, the door 112 may be installed at the outer end of the steel box girder 110. However, the door 112 may be provided at the outer end of the steel box girder 110 according to the geographical conditions in which the girder 100 contacts. And may be installed on the lower surface of the steel box girder 110 as shown in Fig. 10 when the installation at the outer end is difficult.

In the case of a general round steel pipe girder, it is impossible to inspect the interior of the round steel pipe girder due to reinforcement of the cross section. However, in the present invention, the internal space of the round steel pipe girder 120 can be maintained as described above.

Therefore, in the present invention, the door 112 can be installed at the outer end of the steel box girder 110, which penetrates the circular steel pipe girder 120, Maintenance and inspection can be easily performed.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the scope of the invention is not limited to the disclosed embodiments, but, on the contrary, It is obvious that it will be possible to carry out various modifications thereof. It is therefore intended that such modifications are within the scope of the invention as set forth in the claims.

100; A girder 110; Steel box girder portion
111; A concrete member 112; door
120; A circular steel pipe girder 121; Circular steel pipe
122; Rigid stiffeners 123; T-type tensile stiffener
123a; Flange 123b; Web
130; Support beam 200; Deck plate
300; A fulcrum portion F; Air flow

Claims (9)

A girder structure of a bridge comprising a girder part (100) and a deck plate (200) provided on the upper part of the girder part (100)
The girder portion 100 is composed of a steel box girder portion 110 placed at an alternate or piered angle and a round steel pipe girder portion 120 placed at a transversal portion between alternate or pierced angles,
A T-shaped tensile stiffener 123 composed of a linear flange 123a and an arch-shaped web 123b is provided below the circular steel pipe girder 120,
When a load is applied to both ends of the circular steel pipe girder 120, the ends of the web 123b are brought into contact with the bottom surface of the steel pipe of the circular steel pipe girder 120, The prestress generated by removing the load is introduced into the round steel pipe girder 120,
A supporting beam 130 is provided between the deck plate 200 and the circular steel pipe girder 120 so that the load acting on the deck plate 200 is transmitted to the circular steel pipe girder 120 through the support beam 130. [ A support beam 130 is installed in the portion where the support beam 130 is not installed so that the air flow portion F is formed between the deck plate 200 and the circular steel pipe girder portion 120 Composite steel pipe girder structure. The composite steel pipe according to claim 1, wherein a stiff stiffener (122) for stress distribution is provided under the circular steel pipe (121) at a portion where the steel box girder (110) and the circular steel pipe girder Girder structure. delete The composite steel pipe girder structure according to claim 1, wherein a width of the flange (123a) is gradually widened from the center toward both ends of the T-type tensile stiffener (123). The composite steel pipe girder structure according to claim 1, wherein the width of the web (123b) gradually increases from both ends of the T-type tensile stiffener (123) toward the center. delete The composite steel pipe girder structure according to claim 1, wherein a door (112) is provided at an outer end or a lower surface of the steel box girder (110). The composite steel pipe girder structure according to claim 1, wherein a concrete member (111) is provided on at least a lower surface of the inner surface of the steel box girder (110). A bridge constructed using a composite steel pipe girder structure according to any one of claims 1, 2, 4, 5, 7 and 8.

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