KR102108551B1 - Continuous Steel Girder System with adjustable CFRP member - Google Patents

Abstract

The present invention in a continuous steel bridge system using an adjustable CFRP member: a point girder (20) coupled to the temporary holding (10); The tension member 30 for mounting the CFRP plate material 35 to the center of the lower surface of the point girder 20 so as to be tensionable; And a reinforcing member 40 for mounting the CFRP sheet material 45 for reinforcing at a point on the upper surface of the point girder 20.
Accordingly, there is an effect of securing safety by increasing the load carrying capacity of the H-shaped steel girder and shortening the air by using a CFRP member that can be adjusted in a temporary bridge that must be quickly installed due to urgent circumstances such as disaster recovery.

Description

Continuous Steel Girder System with adjustable CFRP member}

The present invention relates to a continuous steel bridge, and more specifically, using an adjustable CFRP member capable of solving the load-bearing limit of the H-beam steel girder on a hypothetical bridge that needs to be quickly installed due to urgent circumstances such as disaster recovery. It relates to a continuous steel bridge system.

Steel bridges using H-beams are mainly applied to temporary bridges, including the DHB method, HIPP method, ATOM method, BTB method, SKO-beam method, TSB method, and TRIAS method. Among them, DHB method, HIPP method, ATOM method, The BTB method etc. introduces tension to increase the rigidity of the girder and to relieve sagging and vibration.

Korean Registered Utility Model Publication No. 0315883 (Patent Document 1), Korean Registered Patent Publication No. 0911451 (Patent Document 1), and Korean Registered Utility Model Publication No. 081100 as related art documents related to temporary bridges using H-beams (Patent Document 3) and the like.

According to Patent Literature 1, it is cumbersome to install a production base to manufacture a double beam and introduces prestress, which causes trouble in fastening bolts to the deformed beam, and the surrounding workers and driving vehicles due to the breakage of the bolts in common use. Can cause great danger. In order to introduce pre-stress, a separate site is required on the site, and it also acts as a factor in increasing construction costs.

Patent Literature 2 is a method of drilling a hole in the upper flange of a mold and synthesizing it with a perforated plate, resulting in a large stress loss of the base material, which greatly reduces the resistance to the actual applied stress, and when the span length is different, the length of the small block is different. Because of the loss, it is difficult to recycle the perforated plate. Particularly in the case of socializing, it is difficult to apply, and the hole of the bolt hole or the perforated plate is often not suitable, and thus the construction performance is poor.

According to Patent Document 3, it is possible to partially reduce the stress of the positive moment part by the prestressing force, but it is difficult to expect a significant reduction in the amount of steel material because the resulting force is not large. Deformation may occur, and there is a high possibility of causing lateral deformation because the tension is separated by separating the left and right sides of the girder.

(001) Korean Registered Utility Model Publication No. 0315883 "A hypothetical bridge using prestressed composite overlapping beams by connecting the beams up and down ..." (Publication date: 2003.06.11.) (002) Korean Registered Patent Publication No. 0911451 "Structure for synthetic hypothetical bridge and construction method with integrated main girder and large-sized perforated plate ..." (Publication date: 2009.08.11.) (003) Korea Registered Utility Model Publication No. 0281100 "Steel-type steel bridge over continuous long distance using long tension" (published: July 13, 2002)

An object of the present invention for improving the above-described conventional problems is to use a continuous steel bridge system using an adjustable CFRP member to solve the limitation of the load carrying capacity of the H-beam steel girder in a temporary bridge that must be quickly installed due to urgent circumstances such as disaster recovery. To provide.

In order to achieve the above object, the present invention provides a continuous steel bridge system using an adjustable CFRP member: a point girder coupled on a temporary column; A tension member for tensionably mounting the CFRP plate to the center of the lower surface of the point girder; And a reinforcing member for mounting a CFRP sheet material for reinforcing at a point on the upper surface of the point girder.

As a detailed configuration of the present invention, the tension member is characterized in that it is possible to adjust the tension of the CFRP plate by connecting the fixing plate and the movable table via a gripping table on both ends of the CFRP plate, with an adjustment bolt and a hydraulic jack.

As a detailed configuration of the present invention, the reinforcing member is characterized by fixing the CFRP sheet material using at least one of a support plate or a clamp.

As a modification of the present invention, the clamp is characterized in that it has a support block divided to support each of a plurality of CFRP sheet materials having support bars at the ends in parallel, and a support shaft guiding the plurality of support blocks to be closely or spaced apart. Is done.

As a detailed configuration of the present invention, the CFRP sheet material and the CFRP sheet material are formed by differentially applying a composition to increase ductility at both ends.

According to the present invention as described above, by using a CFRP member that can be adjusted in a temporary bridge that must be quickly installed due to urgent circumstances, such as disaster recovery, there is an effect to secure the safety by increasing the load-bearing capacity of the H-beam steel and shorten the air.

1 is a table of simulation results for deriving the present invention
2 is a schematic diagram schematically showing a system according to the present invention
3 is a schematic diagram showing a detailed configuration of a system according to the present invention
4 is a schematic diagram showing a modification of the system according to the present invention

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The present invention proposes a continuous steel bridge system using an adjustable CFRP member. It is targeted to apply Carbon Fiber Reinforced Polymer (CFRP) to temporary bridges of temporary beam structures that are temporarily constructed, but is not limited thereto.

According to the present invention, the point girder 20 is combined on a plurality of temporary holdings 10 to form a temporary bridge. In the case of a continuous beam system by a temporary holding (10) and a point girder (20), a parent moment occurs at the point, and a positive moment occurs at the center between the points. Big. Therefore, a bridge is formed by reinforcing the point portion where the parent moment acts, and in this process, the bending stiffness of the point portion increases, resulting in a side effect of increasing the parent moment of the point portion. On the other hand, the central part where the positive moment occurs is reinforced by applying a prestressed tension force to the bottom of the girder.

1 and [Table 1] summarize the maximum bending moment according to the presence or absence of point reinforcement and the presence or absence of central reinforcement by giving equally distributed loads to a generally used 3-span continuous beam system. It can be seen that the existing method of increasing the stiffness of the branch part has a larger maximum bending moment.

Continuous beam section type Fig. 1 Branch
Bending moment Central
Bending moment Constant cross section (a) 1.57 1.33 Center reinforced constant cross section (b) 1.47 0.91 Branch reinforcement section (c) 2.07 1.18 Center reinforced point reinforcement cross section (d) 1.80 0.78

In addition, according to the present invention, the tension member 30 is a structure in which the CFRP plate 35 is mounted to the center of the lower surface of the point girder 20 so as to be tensionable. Normally, in reinforced concrete structures, CFRP reinforcement is applied by being attached to or embedded in the lower surface. In the case of a temporary bridge, it is attached in a state exposed on the lower surface of the point girder 20, and a protective cover for blocking external shock can be provided. In FIG. 2, a state in which the length of the CFRP plate 35 is set differently in correspondence to the spacing of the temporary holding column 10 is illustrated. As shown in FIG. 3, a plurality of point girders 20 may be disposed adjacent to each other and may be combined through a connecting portion 25.

In addition, according to the present invention, the reinforcing member 40 has a structure in which the CFRP sheet material 45 for reinforcing is mounted on the upper surface point portion of the point girder 20. From the results of FIG. 1 and [Table 1] described above, it is reasonable to reinforce the CFRP sheet material 45 by attaching the CFRP sheet material 45 rather than a method of increasing rigidity at the point. The CFRP sheet material 45 may be made of a thin and relatively rigid material such as a carbon fiber composite material and excellent in strength.

As described above, when the CFRP plate 35 is tensioned in the central part to generate and reinforce the parental moment, and the CFRP sheet material 45 is simply reinforced by attaching the CFRP sheet material 45 at the point, approximately 29% of the reinforcement effect appears. .

As a detailed configuration of the present invention, the tension member 30 is connected to the fixing table 31 and the movable table 32 through the gripping table 33 on both ends of the CFRP plate 35, and the adjustment bolt 36 And hydraulic jack 38, it is possible to adjust the tension of the CFRP plate (35). The anchor 31 fixed by the anchor bolt simply supports one end of the CFRP plate 35 with the grip 33. The movable table 32 supports the other end of the CFRP plate 35 with a gripping table 33 with a block 32b movable on a base 32a fixed with anchor bolts. The gripper 33 may be at least partially coupled with the CFRP plate 35 with an adhesive or the like. The adjustment bolt 36 is mounted on a movable part of the movable table 32 to loosen the nut and change the tension acting on the CFRP plate 35 as it is tightened. The hydraulic jack 38 is mounted between the base 32a and the block 32b on the movable table 32. The hydraulic jack 38 does not need to be connected to an external hydraulic device, and only one is mounted below the CFRP plate 35 to adjust the tension. Due to the nature of the temporary bridge, the air is tight and it is quick and convenient to adjust and correct the tension in the field.

At this time, as shown in Figure 3, when a plurality of bridges 15 are mounted on one temporary holding column 10, it is preferable to install the CFRP sheet material 45 at a length greater than the separation distance of the two sides of the bridge 15.

On the other hand, the adhesive uses a two-component type room temperature curing type epoxy resin adhesive in which the main agent and the curing agent are mixed in a weight ratio of 2: 1.

As a detailed configuration of the present invention, the reinforcing member 40 is characterized by fixing the CFRP sheet material 45 using at least one of the support plate 41 or the clamp 43. Although attaching the CFRP sheet material 45 with a conventional adhesive is advantageous for shortening the construction time, discomfort and risk increase during the dismantling of the temporary bridge. The support plate 41 is integrally coupled to the end portion of the CFRP plate material 35 by an adhesive or the like, and is fastened directly to the point girder 20 using bolts during construction. The clamp 43 is fixed to the point girder 20 by bolts, which is the same as the support plate 41, but the CFRP sheet material 45 can be detached or stacked in a simpler manner. The method of using two support plates 41 for one CFRP sheet material 45, the method of using support plates 41 and clamps 43 is preferred, and the method of using two clamps 43 is non- It is economical.

As a modification of the present invention, the clamp 43 is divided into a support block 52 and a plurality of support blocks divided to support a plurality of CFRP sheet materials 45 each having a support bar 42 at an end in parallel. 52) is provided with a support shaft 54 to guide the contact or spaced apart. In FIG. 4, the clamp 43 illustrates a state in which a plurality of divided support blocks 52 are stacked so as to move up and down on the support shaft 54. Between the upper and lower support blocks 52, a gap is formed through which the CFRP sheet material 45 is withdrawn. The end of the CFRP sheet material 45 is integrally coupled to the support bar 42 using an adhesive or the like. The support shaft 54 is spirally engaged with the point girder 20 at the bottom and has a knob 56 at the top. Thus, it is easy to separate or combine the CFRP sheet material 45 after opening the support block 52 by turning the knob 56 with a tool or hand.

As a detailed configuration of the present invention, the CFRP plate material 35 and the CFRP sheet material 45 are formed by differentially applying a composition to increase ductility at both ends. CFRP plate material 35 and CFRP sheet material 45 are produced by combining carbon fiber strands, glass fiber strands, resins, and the like, and in particular, a composition for preventing brittle fracture due to linear stress-strain behavior is important. The CFRP sheet material 35 is required to have a relatively high ductility at a portion in contact with the gripping table 33, and the CFRP sheet material 45 is required to have a relatively high ductility at a portion coupled with the support bar 42. In any case, it is important to adjust the content to increase the strength and durability while reducing brittle fracture in a certain section of the ends of the CFRP sheet material 35 and the CFRP sheet material 45.

As an example of construction, as shown in FIG. 3, the point girders 20 are combined on the temporary holding column 10, and then the tension member 30 capable of adjusting the tension force and the reinforcement member 40 for simple reinforcement are installed to provide a continuous steel bridge system. Make up. Thereafter, the hydraulic jack 38 of the tension member 30 is operated to install the CFRP sheet material 45 in a state in which the tension is varied, and finely adjusted with the adjustment bolt 36 so that the positive moment and the parent moment reach the set range. By separating the hydraulic jack 38, an optimal continuous beam system can be realized.

It is obvious to those skilled in the art that the present invention is not limited to the described embodiments, and can be variously modified and modified without departing from the spirit and scope of the present invention. Therefore, such modifications or modifications will have to belong to the claims of the present invention.

10: hypothesis 15: bridge
20: point girder 25: connection
30: tension member 31: fixture
32: movable table 33: holding table
35: CFRP plate 36: Adjustment bolt
38: hydraulic jack 40: reinforcement member
41: support plate 42: support bar
43: Clamp 45: CFRP sheet material
52: support block 54: support shaft
56: knob

Claims (5)

In a continuous steel bridge system using an adjustable CFRP member:
Branch girders 20 coupled to the temporary holding (10);
The tension member 30 for mounting the CFRP plate material 35 to the center of the lower surface of the point girder 20 so as to be tensionable; And
Reinforcement member 40 for mounting the CFRP sheet material 45 for reinforcement on the upper surface point portion of the point girder 20;
The tension member 30 connects the fixing table 31 and the movable table 32 through the gripping table 33 at both ends of the CFRP plate 35, and the two adjusting bolts 36 facing each other. It is possible to adjust the tension of the CFRP plate 35 with one hydraulic jack 38 of the
The reinforcing member 40 is fixed to the CFRP sheet material 45 using at least one of the support plate 41 or the clamp 43,
The clamp 43 is a support block 52 divided to support a plurality of CFRP sheet materials 45 each having a support bar 42 at the end in parallel, so that the plurality of support blocks 52 are in close contact or spaced apart. Continuous steel bridge system using an adjustable CFRP member, characterized in that it has a guide support shaft (54). delete delete delete The method according to claim 1,
The CFRP plate 35 and CFRP sheet material 45 is a continuous steel bridge system using an adjustable CFRP member, characterized in that formed by differentially applying a composition to increase ductility at both ends.

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