KR102625763B1 - Variable type steel composite girder bridge structure in which the number of girders is variable according to member force distribution and construction method thereof - Google Patents

Abstract

The present invention relates to a variable composite girder bridge structure in which the number of girders is variable according to load distribution, comprising: a wall; a variable composite girder part configured in an upper part of the wall, including a plurality of central girders formed in a central part thereof, having end girders formed at both ends with a smaller number than the central girders, and including a connection part that is composed of a plurality of first connection ends connected to the central girder at one end, and second connection ends connected to the end girders with a smaller number than the first connection ends at the other end; and a concrete part poured on a reflex angle part formed by the wall and the variable composite girder part, and an upper part of the variable composite girder part. A purpose of the present invention is to provide the girder bridge structure in which the number of girders is variable according to the load distribution within a span and a construction method thereof.

Description

Variable type steel composite girder bridge structure in which the number of girders is variable according to member force distribution and construction method thereof}

The present invention relates to a steel composite girder bridge structure that is economical and easy to construct by allowing the number of girders to vary depending on member strength, and to a construction method thereof.

In the domestic construction market, as perceptions of labor change, it is recognized that efforts are needed to improve the difficulties in supplying and supplying labor due to a decrease in young skilled workers due to the avoidance of construction sites and the problem of quality deterioration due to site conditions.

As a solution to this, the demand for section steel girder bridges is increasing, in which standardized products such as section steel are simply processed in a factory and then transported to the site and assembled.

Compared to concrete bridges, the on-site work period is shorter, no space for manufacturing or storage is required, and its relatively light weight allows for stable construction even under temporary construction.

However, due to the recent rise in steel prices, relatively high construction costs and difficulties in supplying materials have become problems, and steel girder bridges so far have been constructed with sections of steel or sheet steel having the same specifications on the outside at regular intervals, as shown in Figure 1. It is placed inside and forms a superstructure.

In general, there is a correlation between the shape height of the girder and the number of girders. In order to lower the shape height of the upper part of the bridge (girder) to secure flood volume in medium and small rivers, the existing girder beam is used to reduce the height of the existing girder beam by considering the lateral distribution effect. Sometimes the design is done by increasing the number of copies by 1 or 2.

In addition, when a load is applied to a simple beam, the distribution of bending moment or shear force generated in the beam is not constant and changes from the starting point of the bridge to the end point, so the height (stiffness) of the girder is determined based on the central part where the maximum bending moment occurs. The girder design is completed by changing the thickness of the upper and lower flanges in consideration of the size of the member force depending on the location, but there are limitations in lowering the height of the girder and optimizing the amount of steel in medium and small bridges.

Republic of Korea Patent No. 10-2263272

Therefore, the purpose of the present invention is to provide a girder bridge structure and a construction method that allows the number of girders to be varied according to the distribution of member forces within the span.

As a means to solve the above-mentioned problems, the variable steel composite girder bridge structure (hereinafter referred to as "structure of the present invention") in which the number of girders is variable according to the distribution of member forces of the present invention includes a wall; It is formed on the upper part of the wall and consists of a plurality of central girders in the central part, a smaller number of end girders than the central girders are formed at both ends, and a plurality of first connection ends connected to the central girder are formed at one end and the other end. a variable steel composite girder portion including a connection portion configured to have a second connection end connected to the end girder with a smaller number than the first connection end; And a concrete portion poured on top of the variable steel composite girder portion.

As an example, in the variable steel composite girder part, crossbeams are formed between central girders and between end girders.

As an example, it is characterized in that a pair of outer girders are further connected to the outermost central girder and end girders by crossbeams.

As an example, the connection part is characterized as a "Y type" with two first connection ends and one second connection end, or a "W type" with three first connection ends and two second connection ends. .

As an example, it is characterized in that a fall prevention zone is further formed consisting of a third connection end connected to the end of the end girder and a support end connected in both directions from the third connection end.

As an example, one or more shear reinforcing bars protrude from the upper surface of the wall, and a bending channel with a plurality of through holes formed at the end is fastened to the end girder so that the bending channel is located outside the shear reinforcing bar, and the bending channel It is characterized in that a steel member penetrating through the through hole and the shear reinforcement is further configured.

As an example, the bent channel consists of a pair each fastened to the lower flange of the end girder, a plurality of fastening through holes are formed on the fastening surface opposite to the flange at the end of the end girder, and a steel tube is formed on the orthogonal surface perpendicular to the flange. A plurality of through holes are formed, and a long hole opposing the fastening through hole is formed in the flange, so that the position at which each bent channel is fastened to the flange is adjusted.

As an example, a fixing ring made of an elastic material is further configured to be fastened to the steel stiffener and fixed to the bending channel while the steel stiffener penetrates the steel through-hole.

As an example, a wheel is formed at the bottom of the orthogonal surface.

Meanwhile, the construction method of a variable steel composite girder bridge structure in which the number of girders is varied according to the member force distribution of the present invention (hereinafter referred to as the "construction method of the present invention") includes the steps of constructing a wall (S10); Installing the variable steel composite girder unit on the wall (S20); And pouring concrete to form a slab on the upper part of the variable steel composite girder (S30).

As described above, the present invention has the advantage of minimizing the amount of steel by allowing adjustment of the number of girders for each position according to member strength and excellent field constructability.

Additionally, due to its structure, it has the advantage of being able to double safety by preventing it from falling during erection.

In addition, when constructing not only a girder bridge but also a ramen bridge structure, there is an advantage in improving constructability by reducing the number of girders at the right corner.

Figure 1 is a perspective view showing a conventional steel girder.
Figure 2 is a schematic diagram showing the structure of the present invention.
Figures 3 and 4 are perspective views respectively showing the "Y" shape and the "W" shape of the present invention.
Figures 5 and 6 are perspective views showing one unit in Figures 3 and 4, respectively.
Figures 7 and 8 are perspective views showing a case where the outer girder is further configured in Figures 3 and 4, respectively.
Figure 9 is a view showing an example of the position where the end girder is configured in the "Y" shape of the present invention.
Figures 10 and 11 are perspective views showing an example in which a fall prevention zone is further configured on an end girder.
Figure 12 is an exploded perspective view showing an embodiment of the present invention.
Figure 13 is a partial view showing another embodiment of the embodiment shown in Figure 12.
Figure 14 is a partial view showing another embodiment of the embodiment shown in Figure 12.
Figure 15 is a block diagram showing the construction method of the present invention.

Hereinafter, the configuration and operation of the present invention will be described in more detail based on the attached drawings. In describing the present invention, the terms and words used in the specification and claims are based on the principle that the inventor can appropriately define the concept of the term in order to explain the invention in the best way. It must be interpreted with meaning and concepts consistent with the technical ideas of.

As shown in Figure 2, the structure (1) of the present invention is characterized by being composed of a wall (2), a variable steel composite girder part (3), and a concrete part (4).

In particular, the variable steel composite girder part 3 is formed on the upper part of the wall 2, as shown in FIG. 3, etc., and is composed of a plurality of central girders 31 in the central part, and at both ends there are fewer girders than the central girder 31. A number of end girders 32 are formed, and at one end a plurality of first connection ends 331 connected to the central girder 31 are formed, and at the other end there are fewer end girders than the first connection ends 331. It is characterized in that it includes a connection portion 33 formed by a second connection end 332 connected to (32).

The reason why the variable steel composite girder unit 3 is configured in this way is that the number of end girders 32 located at the ends is smaller than the central girders 31 located at the center according to the distribution of member forces within the span. To achieve this, the central girder 31 and the end girders 32, which are fewer in number than the central girder 31, are connected by the connection portion 33.

Here, the central girder 31, the connecting portion 33, and the end girders 32 may be factory manufactured by welding, etc., but may also be joined by bolting using the connector 35, as shown in FIGS. 5 and 6. there is.

Preferably, in terms of ease of manufacture, connection by bolting using the connector 35 is appropriate.

In addition, in the variable steel composite girder unit 3, a cross beam 34 is formed between the center girders 31 and the end girders 32 so that each center girder 31 and the end girders 32 are supported. It is done.

The crossbeam 34 can also be manufactured by welding, but in terms of ease of construction, it is appropriate to fasten it by bolting.

In the present invention, two embodiments of the connection portion 33 are presented as shown in FIGS. 3 to 6.

The connection portion 33Y of the embodiment shown in FIGS. 3 and 5 is “Y-shaped” with two first connection ends 331 and one second connection end 332.

The connection portion 33Y of this embodiment has the ends of the center girder 31 connected to two first connection ends 331 and the ends of the end girders 32 connected to one second connection end 332. This is to ensure that 1/2 of the end girders (32) are constructed compared to the central girders (31).

In addition, the connection portion 33W of the embodiment shown in FIGS. 4 and 6 is a “W type” having three first connection ends 331 and two second connection ends 332.

The connection portion 33W of this embodiment is such that the ends of the center girder 31 are connected to each of the three first connection ends 331, and the ends of the end girders 32 are connected to each of the two second connection ends 332. By doing so, 2/3 of the end girders (32) are formed compared to the central girders (31).

Among these, the positions where the connection portion 33Y and the end girder 32 are preferably configured in the “Y type” shown in FIG. 5 are as follows.

The distribution of bending moment in a simple beam is as shown in Table 1 below, and the location where the bending moment corresponding to 1/2 of the size of the maximum moment in the moment distribution diagram (Bendig Moment Diagram) is generated can be determined through the quadratic equation as follows. Each was calculated.

Based on these calculation results, as shown in FIG. 9, the second connection end 332 and the end girder 32 are located at a position corresponding to 0.146L, thereby ensuring an appropriate amount of girders.

① Maximum moment at the center

② Moment at an arbitrary point

③ Position where the moment is 1/2 of the maximum moment

☞If you solve it with the root formula,

Based on the position calculated as above, the number of girders is increased at locations where the member force (bending moment or shear force) is large, and at locations where the member force is small, the number of girders is placed small, and at locations where the number of girders changes, the connection part 33Y or connection part By using (33W), the central girder (31) and the end girder (32) are arranged in a 2:1 or 3:2 arrangement, thereby rationally distributing the amount of steel, reducing the amount of steel used compared to the existing construction method, and reducing construction costs and carbon emissions. This is to ensure that it can be reduced.

A comparison of the amount of steel used in an example of the existing steel girder shown in FIG. 1 and the variable steel composite girder part 3 of the present invention shown in FIG. 3 is shown in Table 2 below.

form existing this invention comparison Required steel quantity 46.654 tons 39.756 tons 1.000 : 0.854

For a bridge with an extension of 30 m, the steel used for the case of arranging 6 girders with specifications of H700 When comparing the materials, it was found that the amount of steel could be reduced by 15%, as shown in Table 2 above.

In addition, in the present invention, in order to further improve resistance to member forces, as shown in Figures 7 and 8, a pair of outer girders (36) connected to the outermost center girder (31) and end girders (32) and crossbeams (34) ) presents a more structured example.

In addition, in the present invention, in FIGS. 10 and 11, the conduction device is composed of a third connection end 371 connected to the end of the end girder 32 and a support end 372 connected in both directions from the third connection end 371. An example in which the prevention device 37 is further configured is shown.

That is, a “Y-shaped” fall prevention device (37) is formed at the end of the end girder (32) and placed on the wall (2) of the variable steel composite girder portion (3), and then the variable steel composite girder portion is damaged by vibration, etc. during the construction process. (3) is to control conduction.

In the case of the fall prevention device 37, in FIGS. 10 and 11, it is composed of a fall prevention device 37a in a "Y-shaped" or bent end of the support end 372 and an unbent support end 372, respectively. A fall prevention zone (37b) is presented.

In the case of this fall prevention device 37, it can be manufactured by welding at the end of the end girder 32, as well as connected by bolting.

Meanwhile, in the present invention, another embodiment that allows the overturning of the variable steel composite girder part 3 to be controlled like the overturning prevention device 37 is presented in FIG. 12 and the like.

In this embodiment, one or more shear reinforcement bars 21 protrude from the upper surface of the wall 2, and the end girder 32 has a bent channel 6 with a plurality of through holes 621 formed at the ends. It is fastened so that the bent channel (6) is located outside the shear reinforcing bar (21), and a through hole (621) of the bent channel (6) and a steel member (5) penetrating the shear reinforcing bar (21) are further configured. It is characterized by .

As shown in the drawing, one or more shear reinforcement bars (21) are placed in the wall (2) to face the end girder (32) placed at the top.

In addition, a plurality of main reinforcing bars 22 are arranged in the wall 2, and some of the main reinforcing bars 22 of the wall 2 are equipped with couplers 24 at the top, are connected to the coupler 24, and are bent. Although not shown in the drawing, the wall-slab connecting main reinforcing bar embedded in the concrete part 4 is constructed.

The wall-slab connecting main reinforcing bar is not shown in the drawing, but is embedded in the concrete part poured at the right corner and the concrete part 4 poured on the upper part of the end girder 32 to form the slab.

The end girder 32 placed on the wall 2 has a bent channel 6 fastened to the end of the end girder 32 so that the bent channel 6 is disposed between the upper surface of the wall 2.

The bent channel (6) is composed of a pair each fastened to the flange (32-1) at the end of the end girder (32), and the fastening surface (61) opposite to the flange (32-1) at the end of the end girder (32). ), a plurality of fastening through holes 611 are formed, and a plurality of fastening through holes 621 are formed on the orthogonal surface 62 orthogonal to the flange (32-1).

The bent channels 6, which are composed of a pair, are each fastened to the flange 32-1 at the end of the end girder 32 so that the fastening surfaces 61 face each other, so that when placed on the wall 2, the bent channels 6 are connected between each orthogonal surface 62. The shear reinforcement 21 is placed so that it is located in .

In addition, a long hole 321-1 opposing the fastening through hole 611 is formed in the flange 32-1 to adjust the position at which each bent channel 6 is fastened to the flange 32-1. .

In the present invention, the bent channels (6) are configured as a pair, and a long hole (321-1) is formed in the flange (32-1) to which each bent channel (6) is fastened, so that when fastened by bolt coupling (7), The position of each bending channel (6) is varied so that it can be fastened to the flange (32-1).

By being configured in this way, it is intended to facilitate construction even in cases where the end girder 32 and the wall 2 are not perpendicular to each other, such as in a skew Rahmen.

That is, after provisionally fastening each bent channel (6) to the end girder (32), the shear reinforcement (21) is placed between the orthogonal surfaces (62) of the bent channel (6) on the upper surface of the wall (2), and the bent channel Adjust the position of (6) to ensure true fastening.

Here, the position adjustment is to allow the steel member (4) to easily penetrate the steel through hole (621) of each orthogonal surface (62) in the bent channel (6) and the shear reinforcement (21) located between them. will be.

The “pre-fastening” mentioned above defines a state in which each bent channel (6) is fixed to some extent to the end girder (32) by loosening the bolt connection (7), and “true fastening” refers to a state in which the upper part of the wall (2) The shear reinforcement (21) is placed between the orthogonal surfaces (62) of the bent channel (6) on the surface, and after adjusting the position of the bent channel (6), the bolt connection (7) is strengthened and completely fixed. is to define.

The steel stiffener (5) is configured to penetrate the steel through hole (621) of the orthogonal surface (62) and the shear reinforcement (21) in the bent channel (6), and is connected to the end girder by the steel stiffener (5). By ensuring that (32) is fixed to the upper surface of the wall (2), it is possible to control positional changes due to impact, etc. during the subsequent pouring of the concrete part (4).

The type of the steel joining material 5 is not limited, and for example, reinforcing bars, etc. may be applied.

On the other hand, when the concrete part (4) is poured with the steel reinforcement (5) inserted so as to penetrate the stiffening through hole (621) and the shear reinforcement (21) of each orthogonal surface (62), vibration due to shock, etc. during concrete placement. The stiffening material (5) may be separated from the stiffening through hole (621) and the shear reinforcement (21) due to energy. When this is done, the positional change due to the impact of the end girder (32) mentioned above cannot be controlled. there is a problem.

Accordingly, in the present invention, as shown in FIG. 13, after the steel material 5 penetrates the steel through hole 621 and the shear reinforcing bar 21, the steel material 5 is elastically applied from the outside of the steel through hole 621. An example is presented in which a fixing ring (8) made of material is installed so that the steel member (5) is fixed more firmly and noise that may be generated by vibration during pouring is controlled.

The type of the fixing ring 8 is not limited as long as it is made of a resilient material. Preferably, the inner diameter of the fixing ring 8 is smaller than the diameter of the steel member 5 before being mounted on the steel member 5, and the outer diameter is made smaller than the diameter of the steel member 5 when mounted. It is reasonable to make it larger than the diameter of the rigid through hole 621.

Meanwhile, as mentioned above, after each bent channel (6) is pre-fastened to the end girder (32), shear reinforcement (21) is located between the orthogonal surfaces (62) of the bent channel (6) on the upper surface of the wall (2). The position of the bent channel (6) is adjusted to ensure true fastening. However, position adjustment of the bent channel (6) may not be easy due to the weight of the upper end girder (32).

In particular, if the upper surface of the wall 2 is uneven due to aggregate, etc., it may not be easy to adjust the position of the bent channel 6.

Accordingly, in the present invention, as shown in FIG. 14, a wheel 622 is further configured at the bottom of the orthogonal surface 62 so that the bent channel 6 can adjust its position, that is, slide, between the wall 2 and the end girder 32. An example is provided to make it easier.

The material of the wheel 622 is not limited, but it must be made of at least a rigid material that has deformation resistance against the weight of the end girder 32.

Meanwhile, the construction method of the present invention includes the step of constructing a wall (S10) as shown in Figure 15; Installing the variable steel composite girder unit on the wall (S20); And pouring concrete to form a slab on the upper part of the variable steel composite girder (S30).

Through the above-described content, those skilled in the art will be able to see that various changes and modifications can be made without departing from the technical idea of the present invention. Therefore, the technical scope of the present invention should not be limited to what is described in the detailed description of the specification, but should be determined by the scope of the patent claims.

1: Structure of the present invention 2: Wall
3: Variable steel composite girder part 4: Concrete part

Claims (10)

A wall with one or more shear reinforcement protruding from the upper surface;
It is formed on the upper part of the wall and consists of a plurality of central girders in the central part, a smaller number of end girders than the central girders are formed at both ends, and a plurality of first connection ends connected to the central girders are formed at one end and the other end. a variable steel composite girder portion including a connection portion configured to have a second connection end connected to the end girder with a smaller number than the first connection end; and
It includes a right angle portion formed by the wall and the variable steel composite girder portion and a concrete portion poured on top of the variable steel composite girder portion,
A bent channel having a plurality of through holes formed at an end is fastened to the end girder so that the bent channel is located outside the shear reinforcing bar, and a steel member penetrating the through hole of the bending channel and the shear reinforcing bar is further configured,
The bent channel is composed of a pair each fastened to the flange of the end girder, a plurality of fastening through holes are formed on the fastening surface opposite to the flange at the end of the end girder, and a plurality of rigid through holes are formed on the orthogonal surface perpendicular to the flange. It is formed in the flange with a long hole opposing the fastening through hole to adjust the position at which each bent channel is fastened to the flange, and a wheel is formed at the bottom of the orthogonal surface to temporarily fasten each bent channel to the end girder. After this, the shear reinforcement is placed between the orthogonal surfaces of the bending channel on the upper surface of the wall, and the position of the bending channel is adjusted to ensure true fastening, making construction easy even when the end girder and the wall are not perpendicular to each other. A variable steel composite girder bridge structure in which the number of girders is variable according to member force distribution, characterized by .
According to clause 1,
A variable steel composite girder bridge structure in which the number of girders is variable according to member force distribution, characterized in that crossbeams are formed between central girders and between end girders in the variable steel composite girder portion.
According to clause 2,
A variable steel composite girder bridge structure in which the number of girders is variable according to the distribution of member forces, characterized in that it further consists of an outermost central girder, an end girder, and a pair of outer girders connected by crossbeams.
According to clause 1,
The connection part has a variable number of girders, characterized in that it is a "Y type" with two first connection ends and one second connection end, or a "W type" with three first connection ends and two second connection ends. A variable steel composite girder bridge structure.
According to clause 1,
A variable steel composite girder bridge structure with a variable number of girders, characterized in that the fall prevention zone is further comprised of a third connection end connected to the end of the end girder and a support end protruding in both directions from the third connection end.
delete delete According to clause 1,
A variable steel composite girder bridge structure with a variable number of girders, characterized in that a fixing ring made of an elastic material is further configured to be fastened to the steel stiffener and fixed to the bent channel in a state in which the steel stiffener penetrates the steel through hole.
delete Step of constructing a wall (S10);
Installing the variable steel composite girder part of any one of claims 1 to 5 and 8 on the wall (S20); and
A method of constructing a variable steel composite girder bridge structure in which the number of girders is variable, comprising: pouring concrete to form a slab on the upper part of the variable steel composite girder (S30).