KR20030012014A - preflex bridge structure using plate girder system - Google Patents

Abstract

PURPOSE: A preflex bridge structure using a plate girder installation method is provided to secure strength for the materials economically and maximally and the required stability without increasing the section of I-steel. CONSTITUTION: The preflex bridge structure(700) using a plate girder installation method comprises: a floor slab(100) installed between abutments(400) as well as between an abutment and a pier(500); preflex girders(200) installed on the lower side of the floor slab(100), and composed of I-steel(210) and lower flange concrete formed around a lower flange(213); and horizontal beams(300) formed between the preflex girders(200), and coupled with horizontal members(310) and diagonal members(320) by bolts, or coupled with flat plates continuously.

Description

Preflex bridge structure using plate girder system

The present invention relates to a preflex bridge structure using a plate girder installation method. More specifically, I-shaped cross section steel such as a beam beam or assembly plate bears a tensile force, and the bridge deck concrete formed on the I-shaped cross section steel to support the compressive force to maximize the material properties, and construction The advantage of easy plate girder bridge construction and the formation of lower flange concrete with pre-stress pre-introduced in the lower part of the I-shaped section steel to support the tensile force required while reducing the amount of expensive steel bridges It is possible to construct, and in particular, the advantages of preflex girder bridge construction, which is particularly advantageous when the height of the bridge is limited in length, have economical and construction convenience. The problem is to eliminate the coarse abdominal and haunch concrete work process to solve the difficulty of quality control, This improves the workability and eliminates the need for additional fall prevention members for the fall prevention of I-shaped section steel by bolting the lateral beam to the truss type or flat plate continuously, reducing material costs and working air. Optimization of bridge design by forming transverse girders with favorable structures to support torsion and bending, such as steel boxes (possibly filled with cement mortar) to compensate for the lack of flexural rigidity caused by excessive parent moments in bridge sections The present invention relates to a preflex bridge structure using a plate girder mounting method.

Among conventional bridge construction methods such as simple bridges or continuous bridges, there are plate girder bridges using plate girder and preflex girder bridges using preflex girder. ,

As shown in Figure 1a, the plate girder bridge method is a bridge beam 500 and a steel beam 10, which is an assembly plate of I-shaped cross section manufactured by assembling the steel sheet when the section steel beam having an I-shaped cross section is 50m or more. Shear formed on the upper surface of the upper flange of the steel beam after installing a plurality of spaced intervals (determined according to the width of the bridge) on the upper surface of the alternating 400, after installing the fall prevention hole between the steel beams Finishing the bridge deck by placing the upper concrete bridge 30 by using a deck plate or steel formwork so that the connecting material 20 is included, the construction is good, the appearance is good, the appearance is beautiful, but the distance is 50m If the mold height is limited by the external environment, it is restricted to increase the cross section of the steel beam, and it is impossible to secure the safety required basically as a bridge. Although it is not limited, it is not economical to increase the amount of expensive steel material, especially in case of continuous bridge, excessive parent moment occurs at the point of pier, and designing girders installed between the batteries of bridge is also a problem in economics. There are many. In some cases, steel box girders are used in place of I-shaped steel, which is more advantageous for flexural and torsional rigidity. However, the design is complicated and, above all, expensive steel plates have to be manufactured inside and outside. Except for the need to quickly build bridges in long or working air, there is a difficulty of choice in the application of conventional bridge construction.

As can be seen in Figure 1b, the preflex girder bridge method is a bridge that can be structurally safe and secure usability by limiting the size of the cross section of the I-shaped cross-section steel when the height of the cross section, which is a problem of the plate girder bridge, is limited If the design is difficult, it has been widely used in recent years due to the advantage that it is possible to secure the required bending stiffness and strength without increasing the cross-section of the I-shaped section steel. In other words, in the state of applying a preflex load to the I-shaped section steel in advance, the concrete is placed on the lower flange and cured, and the pre-flection load is removed. Tensile force to be borne by the cross-section steel is relatively small, there is an advantage that can secure the required design force without increasing the cross section of the I-shaped cross-section steel. However, since the conventional preflex girder 50 is transported to the site with the lower flange concrete formed, it is mounted on the pier and the shift at the site, so that the separate abdominal concrete 40 and the haunch concrete 60 at the site Since the construction is very complicated, and even if the abdominal concrete 40 and the haunch concrete (60) is coated and installed, a plurality of holes in the steel at regular intervals to reinforce the reinforcement to the abdomen and the haunch concrete The addition of the forming process is very poor in workability, and further, by forming a number of holes in the steel, there are problems such as steel section loss, the resulting change in mechanical function, discontinuity of internal stress transmission.

Therefore, the present inventors secure economical maximum ease of construction and material strength, which is an advantage of plate girder bridge, and provide support capacity required without increasing the cross section of I-shaped section steel even if there is a limitation of the height compared to the space, which is an advantage of preflex girder bridge. It combines the advantages that can be secured, but the upper flange portion of the preflex girder is installed so as not to be inserted into the upper concrete of the bridge, to increase the bending moment that can be supported by the upper concrete of the bridge to secure more effective bearing capacity It is economical, and there is no trouble in construction by placing concrete in the field and problems such as loss of cross section that can be caused by forming holes in I-section steel without placing abdominal and haunch concrete of preflex girder. The outer surface of the I-shaped section steel by fireproof coating By reinforcing and installing a transverse beam bolted to the truss type or flat plate continuously between the preflex girders, there is no additional fall prevention hole, which saves material. In order to secure bending stiffness due to the parent cement, the plate girder installation method allows for more efficient continuous bridge construction by installing lateral girders such as steel boxes (including cement mortar filled inside) without increasing the cross section of the entire preflex girder. A preflex bridge structure was developed.

The object of the present invention is to secure the maximum economical ease of construction and material strength, which is an advantage of the plate girder bridge, and the stability of the requirements without increasing the cross section of the I-shaped section steel even though there is a limitation of the height compared to the space, which is the advantage of the preflex girder bridge. It combines the advantages of securing (supporting force), but the upper flange portion of the preflex girder is not inserted into the upper concrete bridge to increase the bending moment that can be supported by the upper concrete bridge to secure more effective bearing capacity It is possible to provide a preflex bridge structure using an economical plate girder installation method.

Another object of the present invention is to solve problems such as loss of cross section that can occur by forming holes in the steel without hitting the abdominal and haunch concrete of the preflex girder and the construction hassle caused by pouring concrete in the field It is to provide a preflex bridge structure using a plate girder installation method.

Another object of the present invention is to install a girder method or a plate girder installation method having a material saving effect by installing a transverse beam bolted to the truss method or flat plate between the preflex girder without installing additional fall prevention holes. It is to provide a preflex bridge structure used.

Still another object of the present invention is to provide a steel box (including cement mortar filled therein) without increasing the cross section of the entire preflex girder in order to secure the bending rigidity due to the parent moment occurring at the point in the case of continuous bridge construction It is to provide a preflex bridge structure using a plate girder installation method that allows the construction of continuous bridges more efficiently by installing the same girder.

1A and 1B are specific examples of conventional plate girder bridges and preplex girder bridges.

2A and 2B are specific examples of the preflex bridge structure using the plate girder mounting method of the present invention.

Figure 2c is a specific example of the preflex bridge structure using the plate girder mounting method of the present invention installed in a continuous bridge.

<Description of Major Codes in Drawings>

100: bridge deck 200: preflex girder

210: Section I steel section 211: Upper flange of section I steel section

212: Abdomen of section I steel 213: Lower flange of section I steel

214: lower flange concrete 220: vertical stiffener

230: shear connector 300: transverse beam

310: horizontal member of the lateral beam 320: inclined member of the lateral beam

330: fixed plate of the side beam 340: flat plate

400: shift 500: pier

600: side girder

700: preflex bridge using the plate girder installation method of the present invention

Preferred embodiments of the present invention will be described with reference to FIG.

The present invention can be divided into the case of the bridge construction of the simple bridge method (concrete example 1) or the continuous bridge method (concrete example 2), in the case of the continuous bridge method (concrete example 2) using plate girders installed on both sides of the bridge Since the preflex bridge 700 is installed, there is a difference that a lateral girder such as a separate steel box is further formed. Hereinafter, the simple bridge and the continuous bridge method will be described separately.

[Example 1 (Simple Method)]

Preplex bridge structure using the plate girder installation method of the present invention in the construction of a simple bridge bridge bridge top plate 100 installed between the shift 400; The lower flange is installed in the longitudinal direction (longitudinal direction) of the bridge upper plate with a predetermined interval on the lower surface of the bridge upper plate 100, and formed around the lower flange 213 of the I-shaped cross-section steel 210 and the I-shaped cross-section steel A preplex girder 200 made of concrete 214; The preflex girder 200 is formed in a plurality of perpendicular to the longitudinal direction (lateral direction) of the bridge top plate with a predetermined interval between the horizontal material 310 and the inclined material 320 is coupled by bolted or the plate is continuous Combined side beams (300, 340), and will be described based on the general bridge construction sequence.

2A and 2B are cross-sectional views of the present invention in which an alternating 400 is illustrated as follows.

In the case of a simple bridge, since the bridge top plate 100 is constructed across the place where the bridge is installed, the bridge 400 is first constructed on both sides of the place where the bridge is to be installed.

After the shift 400 is installed, a plurality of preplex girders 200 are installed at regular intervals between shifts and shifts. The preplex girder 200 is usually manufactured on land to be mounted with a crane. The preflex girder 200 is composed of an upper flange 211, an abdomen 212 and a lower flange 213 by processing a steel sheet, the upper surface of the upper flange 211 shears the reinforcement of the adhesive portion with the bridge top plate The connection member 230 is further formed, and between the upper flange 211 and the lower flange 213 by applying a predetermined size of preflex load to the I-shaped cross-section steel is further formed a vertical stiffener 220 for reinforcing the bending rigidity In the state where the rising is formed, when the concrete of a certain cross section is poured and cured to form a lower flange concrete 214 in the lower flange 213, and the preplex load is removed, the I-shaped section steel is subjected to the elastic return force. By applying a compressive force to the lower flange concrete 214 through the process to return to the original shape by the pre-stress is introduced, the tensile force due to the external load as well as the lower flange of the I-shaped cross-section steel Am, the prestressed concrete by introducing a lower flange not always share allotment without the expensive steel discretion of the stiffness and strength is increased, it is more possible to build bridges between the middle finger. At this time, the abdomen 212 and the upper flange 213 portion (hunting portion) of the I-shaped cross section steel exposed to the outside as shown in Figure 2a is mounted on the alternation, the concrete is poured in the field and finished.

Therefore, before placing abdominal concrete and second-hand concrete, reinforcing bars should be placed inside. To reinforce this, holes are drilled at regular intervals in the abdomen of the exposed preflex girder. These holes cause cross-sectional loss of the abdomen and create structural weaknesses because they can form discontinuous surfaces of stress transfer. In addition, in order to hit the haunch concrete, a hole penetrating the haunch is formed to reinforce the reinforcing bar. This hole forming work is very cumbersome, and it can lead to sub-construction, so that quality control is difficult. This is also the case when it is coated in advance)

Therefore, the preflex girder 200 of the present invention is mounted on a shifter with a crane, leaving the abdomen and the haunch concrete unpoured, and finishing by applying a fireproof coating as a measure for protecting the outer surface. In the case of hitting the abdominal concrete and the haunch concrete, cracking may occur later due to the lack of adhesive force, and thus a problem of the unworking of the preflex girder may occur, which is required by the horizontal beams 300 and 340 described below instead of placing them. It secures the stiffness and strength, and further complements by forming a number of vertical stiffeners in the I-type steel. This eliminates the need for a separate wet concrete pouring process, improving workability and facilitating quality control.

After installing a plurality of preflex girders 200 on the shift 400, the horizontal beam 300 is installed as shown in FIG. 2A at right angles between the preflex girders 200, or a flat plate 340 as shown in FIG. 2B. do.

The number of the horizontal beams 300 and the flat plate 340 is determined according to the length and width of the bridge deck (preferably installed at intervals of 9 m or less), and is formed perpendicular to the direction in which the preflex girder 200 is installed. That is, the angle or steel plate horizontal member 310 is fastened to the vertical stiffener 220 by using the fixing plate 330 at the upper and approximately middle portions between the preflex girder 200 except the outer side preflex girder 200. It is installed by, and a plurality of inclined members 320 are installed between the upper and lower horizontal members 310 inclined by using a fixed plate. The horizontal beam 300 restrains the installed preflex girder 200 in the horizontal direction to serve as the conduction zone of the preflex girder 200, and also serves to compensate for the torsional rigidity generated in the horizontal direction. In addition, since the horizontal beam 300 is installed, a separate fall prevention hole does not need to be installed, thereby reducing the material cost, and the production and installation of the preflex girder 200 is simplified, thereby reducing the air.

Another embodiment of the transverse beam 300 is a plate 340. That is, as described above, the flat plate is coupled to the vertical stiffener by the connecting bolt without using the horizontal material and the inclined material.

After the installation of the preplex girder 200 and the transverse beams 300 and 340 is completed, a deck plate or formwork is installed on the preflex girder 200, and the bridge slab concrete is poured to cure to complete the bridge deck. In this case, the upper flange of the preflex girder of the conventional preflex girder bridge is installed to be inserted into the bridge top plate as shown in FIG. 1B. In the present invention, the upper flange of the preflex girder 200 is installed to be in contact with the inside of the bridge top plate without being inserted. . Therefore, it is installed in the same manner as the installation method in plate girder bridge.

When the preflex girder 200 is installed as described above, the cross-sectional core of the bridge deck concrete is formed above the case of installing the conventional preflex girder bridge, and eventually the central axis of the preflex girder 200 of the present invention is upward. Will move. Therefore, the ability to support the compressive force is excellent, and the concrete shear surface of the low-cost bridge deck 100 can resist the compressive force has the advantage that it is possible to use a very economical bridge deck.

After the bridge top plate 100 is completed, asphalt or concrete is laid on the top surface of the bridge plate, and finished to finally complete the bridge.

[Example 2 (Continuous Bridge Method)]

Preflex girder bridge structure using the plate girder installation method of the present invention in the continuous bridge bridge construction bridge top plate installed between the bridge and the bridge (500); The lower flange is installed in the longitudinal direction (longitudinal direction) of the bridge upper plate with a predetermined interval on the lower surface of the bridge upper plate 100, and formed around the lower flange 213 of the I-shaped cross-section steel 210 and the I-shaped cross-section steel A preplex girder 200 made of concrete 214; The preflex girder 200 is formed in a plurality of perpendicular to the longitudinal direction (lateral direction) of the bridge top plate with a predetermined interval between the horizontal member 310 and the inclined member 320 are coupled by bolted or the plate is continuous The first embodiment differs from the first embodiment in that the combined beams 300 and 340 are coupled to each other, so that the preflex girder bridge 700 using the plate girder mounting method of the present invention is installed on both sides of the pier. Done. Therefore, the size of the cross section of the preflex girder 200 can not only be determined according to the size of the parent cement, and it is very unreasonable to design the entire span as a cross section capable of supporting the maximum parent cement. If the length exceeds 50m, the difference in the central axis between the inequality cross sections becomes large, and the internal inaccuracy is generated. Therefore, in the present invention, by installing a cement mortar-filled transverse girder 600, which is a very advantageous structure for bending and torsional stiffness, such as a steel box on the pier 500, as shown in Figure 2c, even in the long point, such as pier It is possible to reinforce bending flexural and torsional stiffness against the generated parent moment, so that the cross section of the preflex girder 200 can be economically designed because the cross section of the preflex girder 200 is not increased more than necessary. It can be very advantageous if the sentence is limited by the external environment. Furthermore, there is an advantage in that the difference between the inequality sections can be minimized and thus the effects of the secondary instability can be less affected.

Except for installing the lateral girder 600 in addition to the same installation as the simple bridge, the preflex girder bridge structure using the plate girder mounting method of the present invention is completed.

The present invention combines the advantages of the plate girder bridge and the advantages of the preflex girder bridge, so that the bridge construction between the long section without increasing the cross section of the I-shaped section steel, the upper flange portion of the preflex girder is not inserted into the upper concrete bridge It is possible to increase the bending moment that can be supported by the upper concrete of the bridge so as to secure the support force more effectively, even if there is a limitation of the section-to-gear ratio, which is an advantage of the preflex girder bridge, the required bearing capacity without increasing the cross section of the steel. It is possible to construct bridges economically in combination with the advantages of securing the core, and problems such as loss of cross section that can be caused by forming holes in I-shaped section steel without placing abdomen and haunch concrete of preflex girder. Solve construction trouble caused by pouring concrete from The material can be saved by installing a truss-type steel beam or flat plate bolted between the reflex girder without installing additional fall prevention holes. In order to secure the bending stiffness by cement, it is possible to construct a continuous bridge more efficiently by installing a girder such as a steel box filled with cement mortar without increasing the cross section of the entire preflex girder.

Claims (4)

In the construction of simple or continuous bridges A bridge deck 100 installed between the shift 400 and between the shift and the piers 500; The lower flange is installed in the longitudinal direction (longitudinal direction) of the bridge upper plate with a predetermined interval on the lower surface of the bridge upper plate 100, and formed around the lower flange 213 of the I-shaped cross-section steel 210 and the I-shaped cross-section steel A preplex girder 200 made of concrete 214; The preflex girder 200 is formed in a plurality of perpendicular to the longitudinal direction (lateral direction) of the bridge top plate with a predetermined interval between the horizontal member 310 and the inclined member 320 are coupled by bolted or the plate is continuous It includes a combined horizontal beam (300, 340), the preflex girder 200 is a pre-flex girder bridge structure using a plate girder installation method characterized in that the concrete is installed without covering the abdomen and haunchi The preflex girder bridge structure according to claim 1, wherein the preflex girder 200 is installed in contact with the inside of the bridge top plate without being inserted into the bridge top plate. The preflex girder bridge structure of claim 1 or 2, wherein a plurality of vertical stiffeners 220 are further formed on the abdomen of the preflex girder 200. According to claim 1, in the case of the continuous bridge bridge construction, between the two plate girder and the preflex girder composite bridge 700 formed on the pier 500, the girder, such as steel box girder or steel box girder filled with cement mortar Preflex girder bridge structure using a plate girder installation method characterized in that the 600 is further formed.