KR200253561Y1 - girder reinforced by truss-typed member - Google Patents

Abstract

The present invention relates to a steel with a truss reinforcement, horizontally continuous in the longitudinal direction of the steel on both sides of the abdomen of the steel having an I-type or H-shaped cross-section used as a bridge girder. The present invention relates to a steel having a composite section with a truss reinforcement integrated with a vertical member and an inclined member.

The steel (for bridge girder) to which the reinforcing material is attached, the horizontal width, the vertical material and the inclined material constituting the reinforcing material distributes the load applied to the upper flange and the lower flange to the shear surface of the steel, and thus the width of the small upper and lower flanges. In addition, the required strength and rigidity can be secured by the thickness, thereby enabling an optimized design of the bridge girder, and the vertical members and the inclined members can increase the abdominal section of the steel to prevent abdominal buckling. In addition, since the stiffness increases the overall rigidity of the steel compared to the same mold height, the mold height is limited, and the rigidity required without increasing the width of the upper and lower flanges compared with the bridge space by the structural calculation is required. It is possible to prevent the decrease in fatigue strength, increase in deflection and increase in vibration and noise due to the whole bridge construction, and is particularly effective in preventing abdominal buckling of steel.

Description

Steel with truss reinforcement {girder reinforced by truss-typed member}

The present invention relates to a steel with a truss reinforcement. More specifically, a truss-shaped reinforcement in which horizontal members, vertical members and inclined members are joined to each other in the abdomen WEB of steel having an I or H-shaped cross section such as a preflex girder or a plate girder is welded or bolted continuously in a longitudinal direction. In addition to the function of transferring the load from the upper flange to the lower flange, the bending stress and shear force due to the external load (concentrated or evenly distributed load) applied to the steel are generally combined with the entire upper and lower flanges. Type I and H cross sections most commonly used as bridge girders by reinforcing the reinforcement and further increasing the stiffness for abdominal buckling that can occur when steel is relatively high (dance) and the width of the flange is small. It relates to a steel with truss stiffeners optimized structural structural mechanism of steel.

Among the girds (BEAM) constituting the conventional bridge upper structure, the steel 40 of the preflex girder or plate girder is usually to the upper flange 10, the abdomen 20 and the lower flange 30, as shown in Figure 1a and Figure 1b. The cover plate 50 is further formed by bolt coupling for flexural reinforcement of the upper flange 10 and the lower flange 30 to supplement the structural performance of the steel, or as shown in FIG. 1B, the horizontal stiffener 60. Alternatively, a vertical stiffener 70 is further formed on the abdomen of the steel to prevent the risk of abdominal buckling as the height of the abdomen increases.

However, in the case of using the cover plate 50, the manufacturing process is cumbersome because separate through holes must be formed in the upper and lower flanges of the steel, and above all, there is a problem that the loss of the cross section as much as the area of the hole, the upper and lower flanges The method of increasing the width and thickness of the is mainly used, and there are few examples in actual design.

In addition, when using the horizontal or vertical stiffeners (60, 70) is advantageous to prevent the buckling of the abdomen, it is used a lot, but because it is not continuously coupled to each other, it is integrated with each other to act on the upper and lower flanges ( There is a problem that it is not economical to use expensive steel to simply prevent buckling because it is insufficient to share bending stress and shear stress due to concentrated load and equal load.

Therefore, the inventors weld or bolt a truss reinforcement material in which vertical, horizontal and inclined materials are continuously integrated on both sides of the abdomen of steel, which consists of upper and lower flanges and webs forming a bridge upper structure (preflex girder or plate girder). By integrating them together, the entire upper and lower flanges support the loads applied to the upper and lower flanges of the steel, and the truss reinforcements share the bending stress and shear stress caused by the loads. In addition, we developed a steel with truss-shaped reinforcement to effectively control the buckling of the abdomen (web), which can occur due to the high height of the steel.

The object of the present invention is to provide a truss-shaped reinforcement consisting of horizontal, vertical and inclined members which can support the bending stress and shear force by the transmitted loads continuously on the abdomen of the steel for the bridge girder and at the same time By integrating by welding or bolting, it optimizes the structural action of the abdomen of the steel for girder bridge having I-shaped or H-shaped cross section, that is, the whole steel supports the bending stress and shear stress caused by external load and the reinforcement By sharing the support of external load and preventing abdominal buckling, it is possible to increase the strength and stiffness of the steel at the same height (dancing) and relatively (when the height is limited, increasing the effective width and thickness of the upper flange) To provide a steel with truss reinforcement that can enhance the steel requirements and safety.

1A and 1B are specific examples of a state in which a reinforcing material is coupled to a steel used as a conventional bridge girder.

Figure 2a and Figure 2b is a specific example of the steel for the bridge girders attached to the truss reinforcement of the present invention.

3 is a cross-sectional view of the steel for girder bridge attached to the truss reinforcement of the present invention.

Figure 4 is a specific example of the bridge is installed steel bridge girder with truss reinforcement of the present invention.

<Description of Major Codes in Drawings>

10: upper flange of normal steel 20: abdomen of normal steel

30: Lower flange of normal steel 40: Steel of normal I cross section

50: cover plate as a conventional reinforcing material

60: Horizontal stiffener as conventional reinforcement

70: Vertical stiffener as a conventional reinforcement

100: steel used as bridge girder 110: upper flange of the steel

120: abdomen of steel 130: lower flange of steel

200: truss-shaped reinforcement 210: horizontal member of the reinforcement of the present invention

220: vertical member of the reinforcement of the present invention 230: inclined member of the reinforcement of the present invention

300: pre-place bridge girder

Preferred embodiments of the present invention will be described in detail with reference to FIGS.

The steel material with a truss reinforcement of this invention includes the bridge girders 100 and the truss-shaped reinforcement 200.

The steel girder 100 for a bridge girder is an assembled plate produced by assembling a steel plate or a plate-shaped steel sheet having an I-shaped cross section and an H-shaped cross section. As can be seen in Figure 2, the upper flange 110, the lower flange 130 and the abdomen (120, WEB). The thickness and width of the upper flange 110 is determined such that the compressive stress due to the maximum bending moment expected in the design is smaller than the compressive stress considering the material strength. Furthermore, some shear forces (including those caused by warping) are also burdened. The thickness and width of the lower flange 20 are determined such that the tensile stress due to the maximum bending moment expected in the design is smaller than the tensile stress considering the material strength. Furthermore, similarly to the upper flange 10, some shear forces (including those due to warping) are also burdened.

The abdomen 120 serves to transfer the load (equally distributed or concentrated load) applied to the upper flange 10 to the lower flange 20 and mainly bears the shear force due to the external load, and the shear force expected in the design Its height and thickness are determined by its size.

The steel 100 of the I-type and H-shaped cross-sections used as the steel of the bridge girder is used as a tension member indicating the behavior of the beam, and the height (dance) of the steel may be limited depending on the site conditions. At this time, when the height of the steel is limited, the thickness and width of the upper and lower flanges should be relatively increased, and the required strength and rigidity (mainly bending) should be increased. It is designed to be designed without sufficient width and thickness of the upper and lower flanges required. Therefore, the safety of the bridge is not only a problem, but also the fatigue of the bridge due to long-term traffic loads and unexpected impact loads. There is a problem that the strength of the bridge itself is relatively low, such as not only the strength is drastically reduced but also the sag is generated and the vibration and noise are increased.

The reinforcement 200 of the present invention is configured such that the horizontal member 210, the vertical member 220 and the inclined member 230 is included in the steel, and is attached to the abdomen of the steel 100 to function as a reinforcing material.

As can be seen in Figure 2, the horizontal member 210, the upper portion which is coupled at right angles to the upper and lower sides of the abdomen both sides of the steel girders for the bridge girders 100 is usually made of a section steel or an assembly plate having an I-shaped section and an H-shaped section And a joining portion of the lower flange by welding or bolt in the longitudinal direction of the steel. The vertical member 220 and the inclined member 230, which will be described later, serve as a support plate to which the upper plate 110 and the lower flange 130 and the coupling portion of the coupling portion of the lower portion 130 and the abdomen 120 act as the coupling plate. Complement the parts structurally.

In FIG. 2, the horizontal member 210 is included. However, the horizontal member is a main function of supporting and supplementing the vertical member and the inclined member which will be described later. Therefore, it is also possible to form the reinforcement member of the present invention without including the same.

As can be seen in Figure 2, the vertical member 220 is usually spaced by welding or bolts between the horizontal member 210 on both sides of the abdomen of the section steel or prefabricated plate steel 100 having an I-shaped cross section and an H-shaped cross section. Multiple are attached. That is, it is fixed vertically along the abdominal surface at a predetermined distance from both ends or at the ends of the steel 100, and transmits and distributes the external load (mainly shear force) transmitted from the upper flange 110 to the lower flange 130. In addition to the structural role, the material strength of the vertical member itself compensates for the shear force caused by external loads. Furthermore, in the case where the height of the abdomen is approximately 3M or more, such as a bridge girder, when the external load is applied as the concentrated load with an eccentricity, there is a fear of abdominal buckling, and the vertical member 220 is attached to the abdominal surface and the abdominal buckling Stiffness (increased abdominal area) increases with respect to abdominal buckling.

One end of the inclined member 230 is bolted or welded to the vertical member 220, and the other end is installed between the horizontal plates 210 to be inclined downward at an approximately 45 degree angle. As can be seen in Figures 2a and 4 can be installed so as to be inclined in one direction with respect to both sides with respect to the middle of the bridge, it can be installed so that the continuous shape as shown in Figure 2b in a continuous mountain shape. As the inclined member 230 is installed, together with the vertical member 220, the external load transmitted from the upper flange is transferred to the lower flange. Since the inclined member is continuously installed in the longitudinal direction in which the abdomen is formed, the external load There is a structural feature that distributes evenly over the entire length of the lower flange. Therefore, by distributing and transferring the load transmitted from the upper flange to the lower flange, it is very structurally advantageous in terms of the mechanism of load transfer. (By distributing and transmitting the load, it is possible to secure the strength and rigidity required by the smaller steel cross section, Efficient design of the upper, lower flanges and abdomen constituting the steel is possible) Furthermore, the inclined material is formed to be inclined approximately 45 degrees on the abdomen surface, and the abdomen is installed alternately with each other in a direction in which a dedicated shear force is applied. The strength exerts support for the shear force, which complements the structural strength of the abdominal shear force. In addition, it is attached to both sides of the abdomen together with the vertical member, and also serves to complement the support for the abdominal buckling.

The horizontal member 210, the vertical member 220, and the inclined member 230 forming the reinforcing member 200 have a truss shape (horizontal member can be omitted) which is entirely coupled to each other by welding or bolting to each other. Therefore, the truss composite structure is additionally installed in the abdomen of the steel material 100, and the complementary bending stress and shear stress (including abdominal buckling prevention) of the steel material, because the horizontal, vertical and inclined members all share, It is possible to reduce the compressive and tensile forces caused by excessive loads on the upper and lower flanges of the steel, and in particular, the bearing capacity for abdominal buckling is improved.

3 is a cross-sectional view of the steel material 100 to which the reinforcing material 200 of the present invention is attached to the preflex bridge girder 300 as a specific example. Pre-Flex bridge girder can mainly reduce the tensile stress acting on the lower flange by prestress. By the present design, the shear force and the abdominal buckling of the girder's abdomen are compensated for, so that the upper and lower limits for the lower mold limit when designing the bridge girder Optimum design of flange width and thickness is possible.

Figure 4 conceptually shows the bridge longitudinal cross-sectional view of the bridge girders using the steel 100 with the reinforcing material 200 of the present invention, the reinforcement is continuously installed in the abdomen of the steel as shown in Figure 2a You can check.

In the case of a conventional bridge girder where the load is concentrated by limiting the mold height by the efficient distribution transfer of external loads and the reduction of compression and tensile force by the reinforcement attached to the steel for the bridge girder of the present invention, It can be reduced by about 20% to 20% to minimize the width and thickness of the upper and lower flanges required for the relatively low mold height, and further prevent the brittle fracture of the entire bridge due to the abdominal buckling of the girder. It is very economical as it can secure safety and durability during the bridge's durability, and it is possible to optimize the bridge design when applying the design of urban overpass and light rail.

Claims (3)

In the steel 100 used as the bridge girder consisting of the upper and lower flanges 110 and 130 and the abdomen 120, web, a plurality of vertical members 220 and the inclined member 230 are continuous at a predetermined interval in the longitudinal direction of the steel. Steel truss reinforcement is attached, characterized in that the truss-shaped reinforcement (200) formed to be attached to both sides of the abdomen (120). In claim 1, the upper, lower flanges (110, 130) of the steel material 100 and both connecting portions of the abdomen 120, a plurality of horizontal members 210 in the longitudinal direction of the steel material 100 is further formed, the vertical material ( Steel and truss reinforcement, characterized in that the 220 and the inclined member 230 is formed between the horizontal member (210). In claim 1 or 2, the attachment of the horizontal member 210, the vertical member 220 and the inclined member 230 of the reinforcing member 200 is coupled to the abdomen of the steel material 100 by bolts or welding, the integration is Steel with attached truss reinforcement, characterized in that.