KR20210035681A - Composite rahmen bridge and constructing method thereof - Google Patents

Abstract

The present invention relates to a composite steel rahmen bridge and a construction method thereof, comprising: a plurality of support steels protruding upward from a wall, arranged in a transverse direction, and having an extended width portion that has the width in the transverse greater than that of a lower end portion at an upper end; a steel girder installed so that both end portions are supported on the support steel; and concrete in which at least a portion of the steel girder and the support steel are integrated with the wall. Thus, the present invention is stable in overturning after construction and prevents an elastic pad from being separated by maintaining its position even if excessive longitudinal inclination occurs during installation of the steel girder.

Description

Steel composite ramen bridge and its construction method {COMPOSITE RAHMEN BRIDGE AND CONSTRUCTING METHOD THEREOF}

The present invention relates to a steel composite ramen bridge and a construction method thereof, and more reliably prevents the conduction of the steel girder in the construction state of the supporting steel type against the wall, and the elastic pad is more reliably installed in the process of mounting the steel girder on the supporting steel type. The present invention relates to a steel-composite ramen bridge that maintains it in place and improves resistance to shear force, bending moment, and axial force acting during common use, and a construction method thereof.

In general, bridges are constructed so that vehicles can more conveniently pass through rivers, seas, or valleys, and a girder manufactured to withstand fixed and live loads acting on the upper structure, and vehicles pass through the upper side of the girder. It is made of concrete with a floor plate formed in a plate shape so that it can be done.

Among the types of bridges, the Rahmen Bridge increases the overall structural rigidity by integrating the lower structure and the upper structure of the bridge and reduces the size of the bending moment generated in the center of the span, but bears the size of the reduced bending moment on the piers and abutments. It is a type of bridge.

Although various methods of construction of the ramen bridge have been proposed, there are prestressed steel reinforced concrete composite ramen bridges and construction methods proposed by Moon, et al. and registered as Korean Patent Publication No. 10-0770574. According to this, as shown in Fig. 1, after pre-installing the supporting steel mold 20 on the wall 10, and mounting the I-shaped steel girder 30 on the supporting steel mold 2, the steel composite girder 30 A steel-composite ramen bridge (9) in which the remaining wall concrete (40) and the deck concrete (50) are simultaneously poured into the wall (10) has been proposed.

In the construction process of the steel composite ramen bridge 9, in the process of mounting the I-shaped steel girder 30 on the support steel mold 20 before pouring the residual wall concrete 40, the width of the support steel mold 20 ( When w2) is equal to or larger than the width (w3) of the lower flange of the steel girder 30, the steel girder 20 is stably mounted on the supporting steel mold 20 to prevent overturning (30r). have.

However, although the supporting steel mold 20 is not a member that receives a large stress by being embedded in the residual wall concrete 40 formed integrally with the wall 10, the steel girder 30 as shown in FIG. Forming a wide enough width (w2) to mount the material has been a cause of an increase in construction cost as an excessive amount of steel is used.

Meanwhile, an elastic pad 60 is interposed between the supporting steel mold 20 of the steel composite ramen bridge 9 and the steel girder 30, and an elastic pad 60 is placed on the upper surface of the supporting steel mold 20. In the process of mounting the steel girder 30 in the mounted state, the steel girder 30 is inclined in the longitudinal direction and pushes the elastic pad 60, making it difficult to accurately install the elastic pad 60 at a predetermined position. There was also.

On the other hand, in a state in which the steel girder 30 is mounted on the supporting steel mold 20, the installation process of the formwork for constructing the residual wall concrete 40 and the floor plate 50 and the process of pouring concrete are performed, This process takes tens of days to several months. Therefore, even if the steel girder 30 is mounted on the supporting steel mold 20 that is sufficiently wide, the wind load acts large during the installation process of the formwork, or if the pouring process of concrete is carelessly performed, the possibility of the steel girder 30 overturning. Still exists. Therefore, a method for stably positioning the steel girder 30 in a state in which the steel girder 30 is supported by the supporting steel mold 20 is being sought.

On the other hand, in the steel composite ramen bridge 9 that has been completed and is in common use, the axial force (Fs) in the longitudinal direction of the steel girder 30, the shear force in the vertical direction (V), and the bending moment according to the fixed load and live load (M) acts on the right leg (A). For this reason, as shown in FIG. 3, cases in which cracks 98 and 99 are generated at the joint portion of the residual wall concrete 40 with the steel girder 20 have been reported several times.

As such, there is an urgent need for a method capable of suppressing damage to the residual wall concrete 40 due to various loads acting during the common use of the steel composite ramen bridge 9.

[Patent Literature]

Republic of Korea Patent Publication No. 10-0638673 (2006. 10. 19)

In order to solve the above-described problems, the present invention aims to lower the construction cost by stably mounting the steel girder on the supporting steel during the construction of the bridge to reduce the possibility of overturning, while reducing unnecessary use of steel.

At the same time, it is an object of the present invention to fundamentally prevent fall by restraining the lateral displacement of the steel girder during the formwork installation process and the concrete pouring process performed while the steel girder is mounted on the supporting steel mold.

In addition, an object of the present invention is to stably maintain the position of the elastic pad interposed between the steel girder and the supporting steel mold in the position even if a force pushed in the axial direction by the steel girder acts.

Above all, it is an object of the present invention to provide a structure for suppressing cracks generated in residual wall concrete surrounding the end of a steel girder by axial force, shear force, and bending moment acting during common use of a bridge.

In order to achieve the object as described above, the present invention is formed protruding upward from the wall and arranged in a number of directions at right angles to the bridge axis, but the width in the direction at right angles to the bridge axis is provided at the upper end compared to the lower steel type forming the lower end. The base of which has been made; A steel girder installed to support both ends of the supporting steel mold; A residual wall concrete formed to integrate at least a portion of the steel girder and the supporting steel mold with the wall; It provides a steel composite ramen bridge, characterized in that configured to include.

In addition, the present invention is formed to protrude upward from the wall and a plurality of support stiffeners arranged in a direction perpendicular to the bridge axis; It has an upper flange, a lower flange, and a abdomen connecting the upper flange and the lower flange, extending in a cross section including an I-shape, and formed of a steel material, and extending downward from the upper flange to the abdomen and the lower flange A steel girder disposed to be arranged in a plurality of rows so as to have a wall end pressure plate extending to a lower side of the lower flange in a form surrounding the lower flange, and to support both ends of the supporting steel mold; A residual wall concrete formed to integrate a part of the steel girder and the supporting steel mold with the wall; A bottom plate synthesized on the upper side of the steel girder; It is configured to include, and the wall end acupressure plate provides a steel composite ramen bridge, characterized in that at least partially exposed on the entire surface of the residual wall concrete.

On the other hand, according to another field of the invention, the present invention is a method of constructing a steel composite ramen bridge, comprising: an installation step of installing a plurality of support steel types protruding upwardly from a wall in a direction perpendicular to the bridge axis; It has an upper flange, a lower flange, and a abdomen connecting the upper flange and the lower flange, extending in a cross section including an I-shape, and formed of a steel material, the upper flange and the upper flange at an end supported by the supporting steel mold. A vertical reinforcement at a point vertically connecting the lower flange, and extending downward from the upper flange at a position spaced from the vertical reinforcement toward the center of the span from the vertical reinforcement to the lower side of the lower flange in a form surrounding the abdomen and the lower flange. A steel girder preparation step of preparing a steel girder having a pressure plate at the end of the wall; A steel girder installation step of installing the steel girder so as to be supported by the supporting steel mold; A formwork installation step of installing a wall formwork for placing concrete for integrating a part of the steel girder and the supporting steel form with the wall; An installation step of installing a remaining wall part of integrally uniting a part of the steel girder and the supporting steel mold with the wall by means of residual wall concrete in which unhardened concrete is poured into the formwork; A floor plate installation step of installing the floor plate concrete to the steel girder; It provides a construction method of a steel composite ramen bridge, characterized in that configured to include.

On the other hand, the'longitudinal direction' and terms similar thereto described in this specification and claims refer to the bridge axis direction, and the'transverse direction','width direction' and similar terms described in this specification and claims are bridges. It is defined as referring to the horizontal direction as the perpendicular direction of the cross axis.

The'front surface' described in the specification and claims is defined as referring to the surface facing the center of the span of the residual wall concrete.

According to the present invention, the present invention is formed to have an enlarged portion having a larger width at the upper portion than in the lower portion of the supporting steel mold, thereby reducing unnecessary use of steel material, while stably mounting the steel girder on the upper surface of the enlarged portion.

According to the present invention, a fall prevention member fixing part for fixing the fall prevention member connected to the steel girder is provided on the widened part of the supporting steel type, and the fall prevention member in the state where the steel girder is mounted on the supporting steel protruding upward from the wall. Accordingly, by restraining the lateral displacement of the steel girder, the effect of stably maintaining the conduction due to wind loads for a long time can be obtained.

According to the present invention, in forming the widening part, the upper end of the widening flange spaced apart in the throttling direction is formed higher than that of the upper plate supporting the elastic pad, so that the force due to the elastic pad mounted on the upper plate being pushed by the girder is reduced in the throttling direction. Even if it acts as, it is possible to obtain the effect of reliably performing the elastic support role between the steel girder and the supporting steel by maintaining the position of the elastic pad in its position.

According to the present invention, a pressure plate at the wall end portion that covers the lower flange and the abdomen from the upper flange of the steel girder and extends downward to the lower side of the lower flange is provided at a position where the steel girder and the residual wall concrete contact each other. By distributing and resisting the stress caused by the axial force and the bending moment acting in the direction to the residual wall concrete, it is possible to obtain the effect of suppressing the crack in the adjacent part of the steel girder and the residual wall concrete.

Here, according to the present invention, the first surface of the wall end of the steel girder facing the girder end is attached to the front surface of the residual wall concrete, and the second surface facing the side of the wall end acupressure plate and the middle of the span is the residual wall. The steel girder is arranged so as to be exposed on the front surface of the concrete and suppresses damage to the residual wall concrete due to shear forces that act greatly at both ends of the ramen bridge, while distributing and supporting the stress caused by the axial force and bending moment to the residual wall concrete. It is possible to suppress cracks in the area where the and residual wall concrete meet each other.

On the other hand, according to the present invention, at least a part of the side surface of the pressure plate at the wall end of the steel girder and the side surface of the pressure plate at the end of the wall and the first surface facing the end of the wall of the steel girder is embedded in the front surface of the residual wall concrete, It may be arranged so that the facing second surface is exposed on the front surface of the remaining wall concrete. In this case, the elastic material is interposed in the section including the bottom surface of the side surface of the pressure plate at the end of the wall, so that the shear force acting largely at both ends of the ramen bridge is applied. By receiving it as an elastic material and distributing and supporting the stress due to the axial force and the bending moment to the residual wall concrete, it is possible to suppress the crack at the part where the steel girder and the residual wall concrete meet each other.

According to the present invention, an additional acupressure reinforcement made of a horizontal member and a vertical member is provided on the steel girder to additionally support the cross-sectional force, while the transverse reinforcement is connected and installed to the steel girder in the transverse direction through this, but the first flange of the transverse reinforcing member and the Since the second flange is arranged in parallel with the pressure plate at the end of the wall, the effect of effectively resisting the axial force acting on the bridge can be obtained.

Through this, the present invention suppresses cracks generated in the residual wall concrete surrounding the end of the steel girder due to the axial force, shear force, and bending moment acting during the common use of the bridge, lowers the possibility of the steel girder's conduction during construction, and uses the steel material. It is possible to obtain the effect of lowering the construction cost by reducing.

1 is a front view showing the configuration of a general steel composite ramen bridge;
Figure 2 is a side view of a state in which a steel girder is mounted on a supporting steel shape in the process of constructing a steel composite ramen bridge;
Fig. 3 is an enlarged view of part'A' of Fig. 1;
4 is a front view showing the configuration of a steel composite ramen bridge according to a first embodiment of the present invention;
Figure 5 is a cross-sectional view taken along line CC and DD of Figure 4;
6A is an enlarged view of the right leg portion of the'B' portion of FIG. 4;
6B is an enlarged view of the right leg portion of the steel composite ramen bridge according to the second embodiment of the present invention corresponding to the portion'B' of FIG. 4;
7 is a view showing the manufacturing procedure of the steel base applicable to the present invention;
8 is a view showing the manufacturing procedure of another type of support steel applicable to the present invention;
Fig. 9 is a perspective view showing a structure in which a support steel type is installed on a wall;
Fig. 10 is a perspective view showing a state in which an elastic pad is installed on the base steel of Fig. 9;
Fig. 11 is a perspective view showing a state in which a steel girder is mounted on the supporting steel mold of Fig. 10;
12 is a perspective view showing a state in which the conduction of the steel girder of FIG. 11 is physically restricted and prevented;
13 is a perspective view showing a state in which a steel girder according to another embodiment of the present invention is mounted on a supporting steel mold;
Fig. 14 is a perspective view showing a state in which a transverse reinforcing member is connected and installed to the steel girder of Fig. 13;
15 is a perspective view of the end configuration of the steel composite ramen bridge according to the first embodiment in a state in which residual wall concrete and a floor plate are poured;
16 is a perspective view of an end configuration of a steel composite ramen bridge according to a second embodiment in a state in which residual wall concrete and a floor plate are poured;
Fig. 17 is a perspective view showing the shape of an integral member of a supporting steel mold and a steel girder applied to the present invention.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. However, in describing the present invention, detailed descriptions of known functions or configurations will be omitted in order to clarify the gist of the present invention.

As shown in the drawing, the steel-composite ramen bridge 100 according to an embodiment of the present invention includes a support stiffener 120 installed to protrude upward from the wall 10, and a support stiffener 120 mounted thereon. The steel girder 130 and the residual wall concrete 140 formed by casting on-site so as to cover at least a part of the end of the steel girder 130 from the wall 10, and a bottom plate synthesized on the upper side of the steel girder 130 ( 150), and an elastic pad 160 interposed between the supporting steel mold 120 and the steel girder 130.

The supporting stiffener 120 includes a lower stiffener 121 installed to protrude upward from the wall 10 already installed, and at an upper end of the lower stiffener 121 in a direction perpendicular to the axle from the lower end of the lower stiffener 121 An enlarged portion 120U having a larger width Wu than the width Wd is provided. The lower rigid shape 121 may be formed in various cross-sections, and may be extended to have an H-shaped cross-section as shown in FIGS. 7 and 8.

As shown in Fig. 7, the widening portion 120U includes a pair of widening flanges 122, a vertical reinforcing member 124 coupled in an erected state to reinforce the rigidity of the widening flange 122, and a vertical reinforcing member 124. Includes a top plate 125 installed to be supported on the upper surface of).

Here, the widened flange 122 may be integrally formed with the lower stiffener 121 on the upper part of the lower stiffener 121, as shown in FIG. 7(a). The widened flanges 122 have a width Wu that is 1.5 times or more larger than the width Wd of the lower part of the lower stiffener 121 and are arranged to be spaced apart from each other in the throttling direction.

In addition, the vertical reinforcement member 124 is coupled in a state erected on one or more of the upper portion of the wide flange 122 and the lower stiffener 121 between the pair of wide flanges 122 to reinforce the stiffness in the vertical direction. As shown in (b) of FIG. 7, the vertical reinforcing member 124 may be coupled to the wide flange 122 in a vertically arranged vertically on the wide flange 122, or the upper portion of the lower stiffener 121 It may be coupled to the abdomen portion of the wider flange 122 in a similar cross-section. Although not shown in the drawing, the vertical reinforcement may be combined in an erected form connecting a pair of widened flanges 122 in the throttle direction. As shown in (b) of FIG. 7, the upper end of the vertical reinforcement member 124 is installed to be disposed at the lower side with an interval marked by'x' compared to the upper end of the widening flange 122. As shown in (b) of FIG. 7, the vertical reinforcement member 124 may be welded to the upper part of the wider flange 122 or the lower steel mold 121.

The upper plate 125 is mounted to be supported on at least one of the upper surface of the lower stiffener 121 and the upper surface of the vertical reinforcing member 124 to be coupled and installed. The upper plate 124 may be installed to be placed on its own weight, or may be coupled by welding. As shown in FIG. 9, in a state in which the upper plate 125 is installed to be supported by the vertical reinforcing member 124, the upper surface of the upper plate 125 is the height indicated by'y' compared to the upper end of the pair of widening flanges 122 Is placed lower than that. Through this, the elastic pad 160 mounted to be supported on the upper plate 125 is in a position-constrained state in the throttling direction.

Here, the dimension of'y' restrains the movement of the elastic pad 160 in the horizontal direction, but is smaller than the height of the elastic pad 160 compressed by placing the steel girder 130 on the elastic pad 160. It is determined by dimensions. Here, "constraining the movement of the elastic pad 160 in the horizontal direction" does not constrain the shear deformation of the elastic pad in the horizontal direction, but means preventing the elastic pad 160 itself from being moved by a horizontal load or the like. do.

The upper end of the widening flange is formed higher than the upper surface of the upper plate, so that the elastic pad 160 located between the upper surface of the upper plate and the steel girder protrudes in the throttling direction (Fig. 10). In the'z' direction).

On the other hand, although not shown in FIG. 7, as shown in FIG. 9, both sides of the pair of widening flanges 122 in a direction perpendicular to the axle axis may be covered by the side plate 126, and the side plate 126 is It is welded to the wide flange 122 to reinforce the stiffness in the vertical direction. In addition, the height of the upper end of the side plate 126 is also disposed higher than the upper surface of the upper plate 125, so that in a state in which the elastic pad 160 is placed on the upper plate 125, The movement is also constrained by the side plate 126.

On the other hand, according to another embodiment of the present invention, as shown in Fig. 8, the support steel mold 120' may constitute an enlarged portion 120U by fastening bolts. That is, a bolt hole 121a is formed on the upper end of the lower steel mold 121, and a pair of widened flanges 122' are fixed to the upper end of the lower steel mold 121 by bolting. That is, the widened flange may be formed integrally with the lower stiffener 121 as shown in FIG. 7, or may be formed by combining separate members with each other as shown in FIG. 8.

Then, the vertical reinforcing member 124 for reinforcing the stiffness in the vertical direction is welded to the upper portion of the pair of widened flanges 122 and the lower stiffener 121 by welding, and then the upper plate 125 so as to be supported by the vertical stiffener 124 ) May be formed by mounting and combining the support rigid form (120').

The supporting steel molds (120, 120') produced as described above may be assembled on site, but they are manufactured in advance in the factory and transported to the construction site of the steel composite ramen bridge 100 to be installed, thereby reducing the construction time at the site. You can also contribute.

In addition, as shown in Fig. 14, the support steel molds 120 and 120' may be fixed by driving anchor bolts to the existing wall 10, and as shown in Figs. 9 to 11, the existing wall ( When 10) is poured, a part of the lower part may be fixed in the form of being embedded in the wall 10.

As described above, as the widening portion 120U is provided in the supporting steel molds 120 and 120', the width Wu in the transverse direction increases, so that the possibility of overturning in the state in which the steel girder 130 is installed can be reduced.

The steel girder 130 is mounted and installed on the elastic pad 160 while the elastic pad 160 is installed on the widened portion 120U.

To this end, first, before the steel girder 130 is mounted on the widening portion 120U, as shown in FIG. 10, the elastic pad 160 is mounted on the upper plate 125 of the supporting steel mold 120. . Even if the elastic pad 160 is not attached to the upper plate 125 and fixed, the elastic pad 160 physically interferes with the upper end of the wide flange 122 and the side plate 126 in the longitudinal and transverse directions, respectively, during construction. The force is transmitted to the elastic pad 160 through the steel girder 130, or a force pushing or pulling the elastic pad 160 while the steel girder 130 is slightly inclined during construction, or the widening portion 120U is Even if it is installed in an inclined state, the elastic pad 160 always maintains the position in place.

Then, it is provided with an upper flange 130a, a lower flange 130b, and a abdomen 130c connecting the upper flange 130a and the lower flange 130b to extend in a cross section including an I-shape and made of steel. The formed steel girder 130 is prepared on site. This may be produced by manufacturing a steel girder having a span length at the site, or may be formed by connecting a plurality of segmented girders previously manufactured at the factory at the site.

As shown in Figure 11, the steel girder 130 has a vertical reinforcing material 131 at a position aligned with the central portion of the supporting steel type 120 in the throttling direction, vertically connecting the upper flange 130a and the lower flange 130b. It is formed in a form attached to the abdomen 130c while being connected. Accordingly, during construction, the vertical force at the end is smoothly transmitted through the steel girder 130 and the support steel 120 and the wall 10 so that it is supported and supported.

In addition, a pressure plate 135 at the end of the wall is formed at a position where the residual wall concrete 140 is joined to the front surface 140s in a poured state. The wall end acupressure plate 135 extends downward in the vertical (vertical) direction from the upper flange 130a of the steel girder 130, and wraps the abdomen 130c and the lower flange 130b, compared to the lower flange 130b. It is formed extending to the lower part.

Here, the wall end acupressure plate 135 is attached to the front surface 140s of the remaining wall concrete 140 with the first surface 135s1 facing the end of the steel girder 130, as shown in FIGS. 6A and 15 And, the second surface (135s2) facing the center of the span of the wall end pressure plate 135 and the side surface (135s3) of the wall end pressure plate 135 are installed to be exposed to the outside. As shown in FIG. 13, a plurality of shear connectors 135a, such as stud bolts, may protrude on the first surface 135s1 facing the wall 10. As shown in FIG.

Accordingly, referring to FIG. 6A, even if the shear force (V) is applied in the vertical direction, the wall end acupressure plate 135 is exposed to the outside of the residual wall concrete 140 with a vertical cross section. The resulting shear force (V) is not transmitted to the residual wall concrete (140). At the same time, when an axial force (Fs) or a bending moment (M) having a horizontal component is applied, the force of the horizontal component transmitted by the steel girder 130 is wide residual wall by the pressure plate 135 at the end of the wall. As it is dispersed into the concrete 140, it is possible to suppress the occurrence of cracks due to concentration of stress at the boundary between the steel girder 130 and the residual wall concrete 140. Moreover, since the force distributed to the residual wall concrete 140 by the wall end pressure plate 135 is double resistance supported by the support steel type 120 fixedly installed and spaced apart from the wall end pressure plate 135, the residual wall concrete 140 ) It is possible to prevent damage to the concrete 140 by more effectively distributing and supporting the stress transmitted within.

Here, referring to FIG. 6A, the horizontal gap (b) between the wall end acupressure plate 135 and the support stiffener 120 is the height of the lower end 135e of the wall end acupressure plate 135 and the upper end of the support stiffener 120 By setting it to 5 times or less of the deviation (a), the dispersion effect by the pressure plate 135 at the end of the wall and the resistance support effect by the support stiffness 120 can be obtained at the same time. If the horizontal distance (b) between the wall end acupressure plate 135 and the support stiffener 120 is greater than 5 times the height deviation (a) between the lower end of the wall end acupressure plate 135 and the upper end of the support stiffener 120, the wall Since all the stresses dispersed by the end pressure plate 135 must be supported by the residual wall concrete 140, the resistance support effect by the supporting steel mold 120 becomes insignificant, which is not preferable.

On the other hand, according to the second embodiment of the present invention, the wall end acupressure plate 135 is, as shown in Figs. 6B and 16, the first surface 135s1 and the side surface 135s3 facing the end of the steel girder 130. It may be installed so that only the second surface 135s2 which is buried inside the front surface 140s of the residual wall concrete 140 and faces the center of the span of the wall end pressure plate 135 is exposed to the outside.

This is, in the above-described first embodiment, the process of arranging the wall formwork 77 for synthesizing the residual wall concrete 140 in parallel with the pressure plate 135 at the end of the wall is very difficult, but shown in FIG. 6B. As shown, in the second embodiment of the present invention, the wall formwork 77 for synthesizing the residual wall concrete 140 may be installed to be supported by the pressure plate 135 at the end of the wall in a shape covering the pressure plate 135 at the end of the wall. In addition, it is possible to obtain the advantage that the installation process of the formwork can be performed more easily.

6B, since the wall end pressure plate 135 is buried in the residual wall concrete 140, the shear force V in the vertical direction in the steel composite ramen bridge 100 is applied to the front surface of the residual wall concrete 140 ( 140s) can be delivered as it is. Accordingly, an elastic material 170 surrounding the entire lower end of the wall end pressure plate 135 and both lower regions is installed, and the shear force V transmitted by the wall end pressure plate 135 is received in the elastic material 70 It will not be transmitted to the remaining wall concrete 140.

At the same time, as in the above-described configuration of Fig. 6A, at the same time, when an axial force Fs or a bending moment M having a horizontal component acts, the force of the horizontal component transmitted by the steel girder 130 is It is distributed to the wide residual wall concrete 140 by the end pressure plate 135, and the stress distributed in the residual wall concrete 140 is supported by the supporting steel mold 120 located at the end side, while the conventional steel girder 130 ) And the residual wall concrete 140, it is possible to solve the problem that the crack 99 occurred due to the concentration of stress at the boundary and implement a more reliable ramen bridge structure.

Meanwhile, as shown in FIG. 13, an end acupressure plate 133 may be provided which is arranged in a vertical direction and coupled to the end of the lower flange 130b of the steel girder 130 ′. By the bending moment acting on the steel girder 130, the end acupressure plate 133 distributes the force component pushing toward the end under the neutral axis of the girder to the residual wall concrete 140 outside the end of the steel girder 130. I can make it.

That is, in the structure where the end pressure plate 133 is not provided, the local tensile stress (compression flange thickness edge portion) caused by the force pushing the residual wall concrete 140 from the lower edge of the neutral axis of the girder end due to the moment component caused by the load during common use. ) Caused by the crack 98, but the present invention is provided with an end pressure plate 133 on the lower end flange of the steel girder 130, so that the local stress is dispersed and the stress level can be controlled so as not to reach the crack.

13, between the vertical reinforcement member 131 at the end of the steel girder 130 and the pressure plate 135 at the end of the wall, a horizontal member 137a coupled to the abdomen of the steel girder 130, and a steel girder An additional acupressure reinforcing member 137 made of a vertical member 137b coupled to the abdomen and the lower flange of 130 may be provided.

The shear force V in the vertical direction by the additional acupressure reinforcement 137 is resistance-supported through the horizontal member 137a, and at the same time, the axial force Fs may be additionally supported by the vertical member 137b.

As shown in Fig. 14, the steel composite ramen bridge 100 has a plurality of rows of steel girders 130 and is disposed in the transverse direction, so that the steel girders 130 are attached to the transverse reinforcement 180 connecting the steel girders 130 in the transverse direction. Thus, it is possible to resist various force components acting on the right leg. In particular, the transverse reinforcing material 180 has a first flange 181 arranged vertically parallel to the wall end acupressure plate 135, the first flange 181 and the first flange 181 and spaced apart in the intersecting direction. The second flange 182 arranged in parallel, and the H-shaped cross section formed of the connecting member 183 extending the first flange 181 and the second flange 182 in the horizontal direction may be formed to extend. And, here, the connecting member 183 of the transverse reinforcing member 180 may be integrally coupled to the bolt hole formed in the horizontal member 137a of the additional acupressure reinforcing member 137 by bolting, or integrally coupled by welding, etc. It is integrally coupled to the girder (130').

As such, the transverse reinforcing member 180 is arranged to connect the steel girder 130 in the transverse direction with the first flange 181 and the second flange 182 erected, so that the bending concentrated on the right leg of the bridge It is possible to obtain an advantage of more effectively resisting the stress of the horizontal component according to the moment M and the axial force Fs to the cross section of the first flange 181 and the second flange 182.

On the other hand, as described above, the steel girders 130, 130' according to the present invention may be manufactured separately from the supporting steel molds 120, 120' and configured to be mounted on the widening portion 120U, but other implementations of the present invention According to the form, as shown in FIG. do.

On the other hand, in the state in which the steel girder 130 is mounted on the supporting steel mold 120, there is a possibility that the steel girder 130 will overturn due to wind load, etc., when the installation of the transverse reinforcement 180 is omitted or is before installation. do.

In order to prevent this, as shown in FIG. 12, a fall prevention member fixing portion 129 is formed in the base steel mold 120 in the form of a rod connecting a pair of wider flanges 122, and the steel girder 130 It may be configured to fix the fall prevention member 88 extending from the fixing hole (130y) of.

Through this, by providing a fall prevention member fixing portion 129 in the widened portion 120U provided on the upper portion of the support stiffener 120 protruding from the wall 10, the fall prevention extending from the fall prevention member fixing portion 129 By restraining the posture of the steel girder 130 on both sides of the steel girder 130 with the member 88, the conduction of the steel girder can be reliably prevented, thereby implementing a safer and more reliable construction.

The fall prevention member 88 may be installed with a cable, as shown in FIG. 12, and may be installed with a steel member such as a-beam or a-beam. In addition, the fall prevention member fixing portion 129 may be formed in the form of a rod connecting a pair of widened flanges 122, and although not shown in this drawing, the upper plate 125 is moved in a transverse direction than the elastic pad 126. After securing a wide width, a ring member may be installed on both ends of the transverse width of the top plate 125 to combine the ring member and the fall prevention member with bolts or the like.

The residual wall concrete 140, reinforcing reinforcing bars 142 such as longitudinal reinforcing bars (142a) and roof reinforcing bars (142b) around the base steel type 120 and the steel girder 130 are reinforced, and the wall 10 It is formed by pouring unhardened concrete into the wall formwork 77 in a state in which the wall formwork 77 is installed in a form extending the upper side of the wall formwork 77.

Then, a floor plate formwork (not shown) is installed, and unhardened concrete is poured to construct the floor plate 150. Accordingly, a steel composite ramen bridge (FIG. 15) according to the first embodiment and a steel composite ramen bridge (FIG. 16) according to the second embodiment are constructed.

On the other hand, the formwork may be formed by constructing together with the floor plate formwork for forming the floor plate 150, and simultaneously pouring the remaining wall concrete 140 and the floor plate concrete.

The steel composite ramen bridge 100 configured as described above may be constructed in the following order.

Step 1 : First, transport the base steel mold 120 provided with the expanded part (120U) manufactured in the factory to the construction site, and the base steel mold 120 is moved upward from the wall 10 so that it is integrated with the wall 10. It has a protruding shape and is installed in a number of directions perpendicular to the bridge axis.

Step 2 : Apart from step 1, the upper flange 130a, the lower flange 130b, and the abdomen 130c connecting them are provided to extend in a cross section including an I-shape and are formed of steel, as described above. A branch vertical stiffener 131 and a steel girder 130 and 130' provided with a wall end pressure plate 135 are prepared at a position spaced from the branch vertical stiffener 131 toward the center of the span.

Here, the steel girders 130 and 130 ′ may be in a form in which a plurality of segmented girders are connected, or may be combined into a single steel plate over the entire length of the steel girders.

Step 3 : Then, in a state in which the elastic pad 160 is positioned on the widened portion 120U of the support stiffener 120, the steel girders 130 and 130 ′ are raised to expand the stiffened support 120. Install the steel girders (130, 130') to be supported. At this time, since the elastic pad 160 is in a state in which movement (movement) is constrained by the wide flange 122 and the side plate 126 in the front and rear, left and right directions, the elastic pad 160 while passing through the steel girders 130 and 130' ), even if the force is applied to it, it stays in the right position.

Meanwhile, according to another embodiment of the present invention, as shown in FIG. 17, the support section 220 and the steel girder 230 may be pre-fabricated as an integral member 223. When the supporting section steel 220 and the steel girder 230 are formed of an integral member 223, the elastic pad 160 may be omitted.

In addition, as shown in Figs. 9 to 11, when the wall 10 is constructed, the lower part of the base steel mold 220 may be combined with the wall 10 in a buried form, as shown in Fig. 14. Likewise, the integral member 223 may be lifted and coupled to the wall 10 with anchor bolts.

In this case, as steps 1 to 3 are performed by one process, the advantage of shortening the construction period can be obtained.

Step 4 : When step 3 is performed, as shown in Fig. 12, in a state in which the steel girder 130 is mounted on the support steel mold 120, the fall prevention member of the widened portion 120U of the support steel mold 120 The fall prevention member 88 is obliquely connected from the top 129 to the fixing hole 130y of the vertical reinforcing member 131 of the steel girder 130 to restrain the lateral displacement of the steel girder 130.

The fall prevention member 88 may be installed with a cable, and may be installed with a steel member such as a-beam or a-beam.

Through this, the possibility of conduction of the steel girder 130 can be completely excluded before the residual wall concrete 140 is synthesized.

Step 5 : Then, a wall formwork 77 for pouring the remaining wall concrete 140 is installed. The wall formwork (77) is for integrating a part of the steel girder (130) and the supporting stiffness (120) with the existing wall (10), and the front surface of the wall formwork (77) according to the degree of exposure of the pressure plate (135) at the end of the wall. The position of wealth changes.

That is, construction so that the side (135s3) of the wall end acupressure plate 135 and the second surface (135s2) facing the center of the span of the wall end acupressure plate 135 are exposed outside the front surface (140s) of the residual wall concrete 140 In order to do so, as shown in Fig. 6A, the wall formwork 77 is installed side by side in a form forming a continuous plane with the side surface 135s3 of the wall end pressure plate 135.

And, in order to construct the first surface (135s1) and the side surface (135s3) of the wall end pressure plate 135 to be buried in the front surface (140s) of the residual wall concrete 140, the lower section and both sides of the wall end pressure plate 135 In a state where a portion of the lower portion is first surrounded by elastic material 170, as shown in Fig. 6B, the wall formwork 77 covers the second surface 135s2 facing the center of the span of the wall end pressure plate 135 It is installed as.

Step 5 : Then, unhardened concrete is poured into the wall formwork 77 to form the remaining wall concrete 140. When the residual wall concrete 140 is sufficiently cured, a part of the right leg portion of the steel girder 130 and the supporting steel mold 120 are integrated with the wall 10 by the residual wall concrete 140.

Step 6 : Then, the floor plate concrete is synthesized on the upper side of the steel girder 130 to construct the floor plate 150, and the pavement surface is formed on the floor plate 150 and handrails are installed to construct a steel composite ramen bridge. Complete. In some cases, step 6 may be performed simultaneously with step 5.

In the above, preferred embodiments of the present invention have been exemplarily described, but the scope of the present invention is not limited to such specific embodiments, and can be appropriately changed within the scope described in the claims.

For example, in the above-described embodiment, the steel girder is an example of a steel girder extended in an I-shaped cross-section, but a box-shaped girder (including an I-shaped cross-section) or an upper flange having two abdomens between the upper and lower flanges. The steel composite ramen bridge according to the present invention may be constructed using a U-shaped girder (including an I-shaped cross section) in which the flange is formed into one and the upper flange is formed into two narrower widths.

100: steel composite ramen bridge 10: wall
120: strong base 120U: widening part
130: steel girder 131: branch vertical stiffener
135: wall end acupressure plate 140: residual wall concrete
150: bottom plate 160: elastic pad
170: elastic body 180: transverse reinforcement

Claims (13)

A supporting steel mold formed protruding upward from the wall and arranged in a direction perpendicular to the bridge axis, and having an enlarged portion at the upper end portion larger than the width in the direction perpendicular to the bridge axis at the lower end of the lower steel mold;
A steel girder installed to support both ends of the supporting steel mold;
A residual wall concrete formed to integrate at least a portion of the steel girder and the supporting steel mold with the wall;
Steel composite ramen bridge, characterized in that configured to include.
The method of claim 1, wherein the widening portion,
A pair of wide-width flanges formed as a part of the lower steel mold or coupled to the lower steel mold, the width of which is 1.5 times or more larger than that of the lower steel mold and arranged to be spaced apart from each other in the throttling direction;
An upper plate installed to be supported on the upper side of the abdomen of the lower rigid shape;
And an upper end of the widening flange is formed higher than an upper surface of the upper plate, and an elastic pad is interposed between the steel girders on the upper surface of the upper plate.
The method of claim 2, wherein the widening portion,
A vertical reinforcement is additionally included between the pair of widening flanges and coupled to one or more of the widening flanges and the upper part of the lower steel mold to reinforce it, and the upper plate is supported on the upper side of the sebo reinforcement. Ramen bridge made of steel.
The method of claim 1,
A fall prevention member fixing part to which a fall prevention member for preventing the steel girder from falling in a state in which the steel girder is mounted is fixed to the widening part;
Steel composite ramen bridge, characterized in that it comprises.
A supporting steel mold protruding upward from the wall and arranged in a plurality of perpendicular directions of the bridge axis;
It has an upper flange, a lower flange, and a abdomen connecting the upper flange and the lower flange, extending in a cross section including an I-shape, and formed of a steel material, and extending downward from the upper flange to the abdomen and the lower flange A steel girder disposed to be arranged in a plurality of rows so as to have a wall end pressure plate extending to a lower side of the lower flange in a form surrounding the lower flange, and to support both ends of the supporting steel mold;
A residual wall concrete formed to integrate a part of the steel girder and the supporting steel mold with the wall;
A bottom plate synthesized on the upper side of the steel girder;
The steel composite ramen bridge, characterized in that the wall end acupressure plate is installed so that at least a part of the pressure plate is in contact with the front surface of the residual wall concrete, and at least part of the pressure plate is exposed.
The method of claim 5,
The wall end acupressure plate is characterized in that a first surface facing the end of the steel girder is attached to the front surface, and a second surface facing the center of the span of the wall end acupressure plate and at least a part of the side surface of the wall end acupressure plate are exposed to the outside. Ramen bridge made of steel.
The method of claim 5,
In the wall end acupressure plate, a first surface and a side surface facing the end of the steel girder are buried in the front surface, and a second surface facing the center of the span of the wall end acupressure plate is exposed to the outside,
A steel-composite ramen bridge, characterized in that an elastic material is interposed between the front surface and the lower end of the acupressure plate.
The method of claim 5,
A vertical reinforcement at a point vertically connecting the upper flange and the lower flange to an end of the steel girder positioned on the upper side of the supporting steel mold;
A girder end acupressure plate coupled to the lower flange in a vertical direction at an end of the steel girder;
Steel composite ramen bridge, characterized in that it comprises a further.
The method of claim 5,
An additional acupressure reinforcement made of a horizontal member coupled to the abdomen and a vertical member having two sides coupled to the lower flange and the abdomen of the steel girder;
A first flange arranged parallel to the wall end acupressure plate and connected to the steel girder, a second flange spaced apart from the first flange and arranged in parallel, the first flange and the second flange And a transverse reinforcing member extending in a cross section including an I-shape and connecting the steel girder in the width direction by having a connecting member coupled to the horizontal member;
Steel composite ramen bridge, characterized in that it comprises a further.
The method according to any one of claims 5 to 9,
The horizontal distance (b) between the wall end acupressure plate and the support steel mold is determined to be 5 times or less of the height deviation (a) between the lower end of the wall end pressure plate and the upper end of the support steel mold. .
The method according to any one of claims 1 to 9,
The steel girder and the supporting steel are integrally pre-fabricated and installed on the wall.
As a construction method of a steel composite ramen bridge,
A support steel type installation step of installing a plurality of support steel types protruding upwardly from the wall in a direction perpendicular to the bridge axis;
It has an upper flange, a lower flange, and a abdomen connecting the upper flange and the lower flange, extending in a cross section including an I-shape, and formed of a steel material, the upper flange and the upper flange at an end supported by the supporting steel mold. A vertical reinforcement at a point vertically connecting the lower flange, and extending downward from the upper flange at a position spaced from the vertical reinforcement toward the center of the span from the vertical reinforcement to the lower side of the lower flange in a form surrounding the abdomen and the lower flange. A steel girder preparation step of preparing a steel girder having a pressure plate at the end of the wall;
A steel girder installation step of installing the steel girder so as to be supported by the supporting steel mold;
A formwork installation step of installing a wall formwork for placing concrete for integrating a part of the steel girder and the supporting steel form with the wall;
An installation step of installing a remaining wall part of integrally uniting a part of the steel girder and the supporting steel mold with the wall by means of residual wall concrete in which unhardened concrete is poured into the formwork;
A floor plate installation step of installing the floor plate concrete to the steel girder;
Construction method of a steel composite ramen bridge, characterized in that configured to include.
The method of claim 12,
In the formwork installation step, the wall formwork is installed in a form that covers the second surface of the wall end acupressure plate facing the center of the span of the steel girder;
An elastic material installation step of installing an elastic material surrounding a partial section of a lower end and a side surface of the wall end acupressure plate; Further comprising before the step of installing the residual wall part;
In the state in which the wall remaining part installation step is performed, the wall end acupressure plate is surrounded by an elastic material in the lower end and a partial section of the side surface, the first surface and the side facing the end of the steel girder are buried in the front surface, and the wall Construction method of a steel composite ramen bridge, characterized in that the second surface facing the center of the span of the end acupressure plate is exposed to the outside.

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