KR101249285B1 - Bridge with prestressed concrete box girder of cantilever support structure by precast bracket, and it`s construction method - Google Patents

Abstract

PURPOSE: A bridge having a pre-stressed concrete box girder with a cantilever part formed of an upper plate integrated precast bracket and a construction method thereof are provided to allow pre-stressing in a perpendicular direction to a bridge to be unnecessary for a cantilever part, and to omit the installation of supporting posts and formworks for the construction of the cantilever part, thereby reducing the construction cost and period and improving the construction quality. CONSTITUTION: A bridge having a pre-stressed concrete box girder with a cantilever part formed of an upper plate integrated precast bracket and a construction method thereof include: a step of installing a main girder in between piers or a pier and an abutment; a step of manufacturing a cantilever part(2), which is formed by integrating a slab-shaped upper plate(20) and a bracket, into a precast concrete member; and a step of installing and coupling the cantilever parts to both sides of the main girder in a perpendicular direction to a bridge.

Description

Bridge with Prestressed concrete box girder of cantilever support structure by precast bracket, and it`s construction method

The present invention relates to a bridge having a superstructure made of prestressed concrete box girder (hereinafter referred to as "PSC box girder") having prestressed in the axial direction and having a box-shaped cross section, and a construction method thereof. . Specifically, in the PSC box girder, the cantilever portion provided on both sides of the housing girder having a box-shaped cross section is formed of a precast member in which the top plate and the bracket are integrally formed, thereby making the cantilever portion perpendicular to the cantilever portion of the PSC box girder. PSC with a cantilevered part is formed by an integrated top plate precast bracket configured to reduce construction cost, shorten the air, and improve the construction quality by eliminating the need for prestressing in the direction, and eliminating the installation of copper bars and formwork for the construction of the cantilevered part. A bridge having a box girder and a construction method thereof.

PSC box girder itself, which is a housing girder, is designed to have a wide bridge width in the direction of the bridge, ie perpendicular to the bridge, when constructing the superstructure of the bridge using a pre-stressed PSC box girder with a box-shaped cross section. The cantilevered section must be increased in the axially orthogonal direction on both sides of the PSC box girder.

Fig. 1 shows a schematic axial perspective view of a PSC box girder bridge having a conventional strut-supported cantilever portion. In the conventional art, when the cantilever portion is installed, the top plate of the PSC box girder is oriented at right angles to the axial direction as shown in the drawing. An upper plate of the cantilever portion made of a long concrete slab-shaped member is installed, and a strut 102 made of a rod-shaped member is inclined on the lower surface of the upper plate of the cantilever portion to form the cantilever portion in a form of supporting the upper plate of the cantilever portion. It was.

However, increasing the size of the PSC box girder, which is a housing girder, increases its own weight and increases the required amount of prestress in the axial direction, thus increasing the amount of tension for the prestress. Done. In the structure that simply extends the top plate of the box girder so that the extended portion corresponds to the top plate of the cantilever portion, as the length of the top plate of the cantilever portion increases, a separate tension member is disposed in the top plate of the cantilever portion in the direction of the axial axis to prestress. There is a need, and the increase in cost is inevitable.

In addition, if the top plate of the PSC box girder and the top plate of the cantilever portion are installed, the cantilever portion needs to be provided with a separate group and formwork for supporting and installing the top plate of the cantilever portion, which increases the construction cost and delays the air. have.

 In addition, in the prior art in which the rod-shaped strut 102 is supported on the lower surface of the top plate of the cantilever portion as shown in FIG. 1, a large moment and shear force are applied at the portion where the strut 102 and the top plate of the cantilever portion are joined. It may be disadvantageous, and furthermore, there is a problem that the possibility of cracking due to stress concentration is very high at the portion supported by the strut 102 due to the one-point bond support by the strut 102.

This type of prior art is also disclosed in Japanese Unexamined Patent Publication No. 2001-164513 (published on June 19, 2001) described in the prior art document.

See FIG. 3 of JP 2001-164513 A (June 19, 2001).

The present invention has been developed to solve the problems of the prior art as described above, specifically, consisting of a PSC box girder, in the construction of a bridge having a superstructure having a wide bridge width in the direction perpendicular to the bridge axis, the housing PSC box By minimizing the size of the girder itself to reduce its own weight and to reduce the amount of tension for the introduction of prestress in the axial direction, the cantilever part is formed to secure the wider bridge width as necessary, but even if the cantilever part length is increased It is not necessary to apply prestressing in the direction, and it is possible to omit the installation of separate clubs and formwork for the construction of the cantilever portion, and also to structurally disadvantage such as stress concentration on the top plate of the cantilever portion in supporting the top plate of the cantilever portion. For the purpose of avoiding .

In order to achieve the above object, in the present invention, a housing having a box-shaped cross section consisting of a side wall, a top plate and a bottom plate, protruding stepped portion protrudes on the outer side of the side wall and is formed long at intervals in the axial direction, and the upper portion The housing bonder is manufactured to have a configuration in which the first coupling reinforcing bar protrudes upward from the plate, and the protruding connecting bar is installed on the outer surface of the side wall at a gap between the protruding step portions in the axial direction. Installing between piers and piers or between piers and shifts; The cantilever part consisting of a top plate and a bracket made of slab is made of precast concrete member, wherein the bracket is composed of a vertical frame, a horizontal frame and an inclined frame, and the horizontal frame is integral with the top plate, and the vertical frame The recess has a vertical recessed portion recessed in the direction of the side wall of the housing, a buried reinforcing bar is located in the vertical recess, and a cutting step is formed at the side of the upper plate which is connected to the upper plate of the housing. Manufacturing a cantilever portion having a configuration in which a second coupling bar protrudes in the direction of the housing above the cutting step portion; Installing each of the cantilever portions on both sides of the axially perpendicular direction of the housing so that the lower end of the vertical frame is supported by the lower protrusion and the upper portion of the vertical frame is sandwiched between the axial gaps of the protruding step; And the buried reinforcing bar and the protruding connecting bar are positioned in the vertical recess, and the cutting step part and the protruding step part face each other so that the first coupling bar and the second coupling bar are located thereon. A superstructure made of a PSC box girder, including coupling the cantilevered portions to both sides of the housing in the axially orthogonal direction of the housing by hardening the filling material in the recess and in the upper space of the cutting step portion and the protrusion step portion, respectively. There is provided a bridge construction method, characterized in that for constructing the bridge construction.

Further, in the present invention, a bridge constructed by such a bridge construction method is provided.

In the bridge construction method and the bridge according to the present invention described above, when the cantilever portion is installed on both sides of the housing vertically in the axial direction of the housing chuck, a temporary fixing device comprising a beam member installed in the vertical direction of the axial shaft is installed on the upper surface of the housing plate. Install; While the lower end of the vertical frame is placed and supported by the lower protrusion and the vertical frame is fitted in the gap between the protruding steps, the upper end of the hanger member is coupled to the temporary fixing device to fix the lower end of the hanger member. By fixing the cantilever to the cantilever portion, the cantilever portion can be suspended by the temporary fixing device to maintain the position of the cantilever portion.

As another embodiment, in the bridge construction method and the bridge according to the present invention, the protrusion stepped portion of the housing is formed with an upward locking projection protruding upward at the end in the direction of the cantilever portion; A downward locking projection protruding downward is formed on an inner surface of the upper surface of the cantilever portion; When the cantilever portion is installed on both sides of the housing axially perpendicular to each other, the vertical frame is fitted in the gap between the protruding steps, and the downward locking jaw is caught inside the upward locking jaw, and the vertical frame of the cantilever portion It may be configured to be in close contact with the outer surface of the side wall of the housing, the position of the cantilever portion on both sides of the housing.

In the bridge of the present invention, a precast member having a structure in which the top plate of the cantilever portion is supported by a bracket is produced in advance, and the precast member is coupled to a box-shaped housing to construct an upper structure of the bridge. In particular, in the present invention, since the top plate is integrally supported with the bracket in the cantilever part, the support area of the top plate becomes wider, and thus stress concentration can be minimized, thereby greatly reducing the risk of cracking and the like. .

Particularly, in the present invention, even if the length of the cantilever portion is increased, it is not necessary to apply prestressing to the upper plate of the cantilever portion in the direction perpendicular to the throttle, thereby reducing the construction cost, and easily increasing the length of the cantilever portion in the direction perpendicular to the throttle as needed. It is possible to build bridges with large bridges.

In addition, according to the present invention can reduce the weight of the PSC box girder, which is a housing girder, and can also reduce the amount of tension required to introduce the prestress in the axial direction can improve the workability and economics.

In particular, when the cantilever portion has a structure in which the bottom surface of the top plate is supported by a rod-shaped strut as in the prior art, since the moment and shear force in the axial direction of the axial direction are generated, the top plate of the cantilever portion must be reinforced not only with reinforcing bars but also with tension members. In the invention, the cantilever portion is formed by a precast member having a structure in which a precast bracket is integrally provided on the lower surface of the upper plate to support the upper plate, and in such a cantilever portion, the bracket bears a load acting on the upper plate. In the axial direction, it is sufficient to reinforce with reinforcing bar only for the interval where bracket is installed. Therefore, there is an advantage that can be economical construction by saving the cost required to reinforce using the tension material.

Furthermore, in the present invention, since the cantilever part is manufactured by itself as a precast member, there is no need to install a separate copper bar and formwork for supporting the top plate when constructing the cantilever part, thereby reducing the construction cost and reducing the air. .

1 is a schematic axial perspective view of a superstructure consisting of a PSC box girder and a strut-supported cantilever portion in a conventional bridge.
FIG. 2 is a schematic perspective view showing a state in which a cantilever part made of a precast member is assembled to a housing girder made of a PSC box girder to form a superstructure in a bridge of the present invention.
3 is a schematic perspective view of a housing girders composed of PSC box girders in a bridge according to the invention.
4 and 5 are schematic perspective views showing different angles of view of the cantilever portion made of precast concrete members, respectively.
6 and 7 are schematic perspective views of the cantilever portion according to the embodiment in which the shape of the bracket is modified.
8 is a schematic perspective view showing a state in which cantilevers are assembled on both sides of the housing by the temporary fixing device.
FIG. 9 is a schematic front view of the cantilever unit assembled to both sides of the housing by the temporary fixing device in the axial direction.
FIG. 10 is a schematic perspective view illustrating a state in which cantilever portions are assembled and filled with filling materials on both sides of the housing perpendicular to the axial direction of the housing header.
FIG. 11 is a schematic enlarged perspective view of a portion that is connected between a top plate of a cantilever portion that is a circle A portion of FIG. 10.
12 is a schematic perspective view of the superstructure of a bridge completed in accordance with the present invention.
FIG. 13 is a schematic perspective view illustrating a state in which a cantilever portion is assembled in a housing container according to another embodiment of the present invention.
FIG. 14 is a schematic perspective view of a housing in the embodiment shown in FIG. 13.
FIG. 15 is a schematic perspective view of a cantilever part applied to the embodiment shown in FIG. 13.
FIG. 16 is a front view illustrating a state in which cantilevers are coupled to both sides of the housing in the embodiment illustrated in FIG. 13.
FIG. 17 is a schematic perspective view illustrating a state in which cantilever parts are assembled and filled with filling materials on both sides of a axial direction of the housingder in the embodiment shown in FIG. 13.
18 is a schematic perspective view of the superstructure of the completed bridge according to the embodiment shown in FIG. 13.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. Although the present invention has been described with reference to the embodiments illustrated in the drawings, it is described as one embodiment, whereby the technical spirit of the present invention and its core configuration and application are not limited.

FIG. 2 is a schematic perspective view showing a state in which a cantilever part manufactured by a precast member is assembled to a housing girder consisting of a PSC box girder to form a superstructure in the bridge of the present invention, and FIG. 3 is a bridge according to the present invention. A schematic perspective view of a housing forming the superstructure of is shown.

The upper structure 100 of the bridge according to the present invention is composed of a housing (1) having a box-shaped cross section, and a cantilever portion (2) which is coupled to the side perpendicular to the direction of the axis of the housing (1). (1) has a box-shaped cross section composed of side walls (11), top plate (12) and bottom plate (13). If necessary, a central partition (not shown) parallel to the side wall 11 may be further provided in the box-shaped cross section of the housing 1.

The top plate 12 of the upper side of the side wall 11 of the housing 1, that is, the cantilever part 2 may be integrally coupled to both sides of the housing in the axially perpendicular direction of the housing 1. At the edge perpendicular to the axial direction protrusion step portion 110 is provided. The protruding step part 110 is installed in the axial direction, but the protruding step so that the vertical frame 210 can be fitted at the position where the vertical frame 210 formed on the bracket 21 of the cantilever part 2 is coupled. The part 110 is cut out. That is, at the position where the vertical frame 210 formed on the bracket 21 of the cantilever part 2 is coupled, the protruding step part 110 does not exist. Thus, the protruding step part 110 is fixed as shown in the drawing. It is installed in the form of an interruption in the direction of the axial length at intervals. The first coupling reinforcement 115 protrudes from the upper plate 12 of the housing top above the protrusion step part 110.

On the other hand, a vertical frame 210 of the bracket 21 to be described later is fitted in the interval between the protrusion step portion 110 in the position where the protrusion step portion 110 is not continuous, that is, the axial direction, the vertical frame ( Protruding connecting bars 117 are installed on the outer surface of the side wall 11 of the housing 1 at intervals between the protruding steps 110 so as to be inserted into the vertical recess 217 of the 210. The protruding connecting reinforcing bars 117 protrude in a state embedded in the side wall 11 of the housing der 1, and as illustrated in the drawing, a plurality of protruding connecting bars are installed at intervals in the vertical direction.

As described above, the protruding step part 110 is positioned on the upper side of the side wall 11, and an additional lower protruding part for supporting the lower end of the vertical frame 210 of the bracket 21 is coupled to the lower side of the side wall 11 ( 120 protrudes to the outer surface of the side wall 11. The lower protrusion 120 is located where the bottom of the vertical frame 210 of the bracket 21 is coupled, as will be described later. That is, the protruding step 110 is not continuous in the axial direction, so that the lower protrusion 120 is located below the side wall of the housing 1 in a vertical position at the interval.

4 and 5 are respectively shown with different angles of view of the schematic view of the cantilever part 2 made entirely of precast concrete members. As illustrated in the drawing, the cantilever part 2 includes a top plate 20 formed in a slab shape, and a bracket 21 integral with the top plate 20 to support the top plate 20. It is. The upper plate 20 has a certain length in the axial direction, in consideration of the construction and transportation of the bridge width and production, only one bracket 21 may be integrally provided on the lower surface of the upper plate 20 or illustrated in the drawings As described above, two or more plurality may be integrally provided at intervals in the axial direction.

The bracket 21 includes a vertical frame 210 corresponding to a vertical line segment of a right triangle, a horizontal frame 211 corresponding to another straight line segment that meets the vertical frame 210 in a right triangle shape, and a right angle. The triangular shape is configured to include an inclined frame 212 corresponding to the hypotenuse. That is, in the embodiment shown in Figs. 2, 4 and 5, the vertical frame 210, the horizontal frame 211, and the inclined frame 212 is arranged in the form of three sides of a right triangle bracket 21 ). In particular, the bracket 21 of the embodiment shown in Figures 2, 4 and 5 is composed of a vertical frame 210, a horizontal frame 211 and the inclined frame 212, the through hole 213 in the center Although it is formed, an additional reinforcement frame 214 that crosses the through hole 213 may be further installed to increase the rigidity of the bracket 21 or to consider aesthetics. Only one reinforcing frame 214 crossing the through hole 213 may be installed, and two or more reinforcing frames may be provided as necessary. Of course, the reinforcement frame 214 may be omitted.

In particular, in constructing the right triangle bracket 21, the horizontal frame 211 is eventually integrated with the upper plate 20, the horizontal frame 211 to the lower surface of the upper plate 20 as illustrated in the figure ) May have a structure in which the top plate 20 and the horizontal frame 211 are integrated with each other. In the present invention, the horizontal frame 211, as illustrated in the figure, not only exists in the form protruding from the lower surface of the upper plate 20, the thickness thereof is the same as the thickness of the upper plate 20 of the upper plate 20 It should be understood to include cases that do not protrude to the lower surface. That is, when the horizontal frame 211 does not protrude in this manner, a portion having a predetermined thickness on the upper plate 20 in the axially orthogonal direction at the position where the bracket 21 exists is extended to the horizontal frame 211 immediately. It is equivalent.

On the other hand, in the shape of the bracket 21, the inclined frame 212 is not necessarily made of a straight line may be made of a curved shape, and furthermore, the shape of the bracket 21 in the bridge according to the invention, Figure 2 4 and 5 are not limited to the embodiment shown in FIG. 6 and 7 respectively show a schematic perspective view of the cantilever part 2 according to the embodiment in which the shape of the bracket 21 is modified. As shown in FIG. 6, the bracket 21 has a through hole 213. It may be made of a plate-shaped precast concrete member made of a triangular plane does not exist and has a thickness in the axial direction, as shown in Figure 7, through-hole 213 of a circular or other various shapes are formed in the triangular plane The bracket 21 may be formed by the plate-shaped precast concrete member. In addition, although not shown, it may be manufactured in the inclined frame 212 of various shapes in consideration of the beauty and structural effects of the side of the bridge.

In the bracket 21 having various shapes, the vertical frame 210 has a predetermined width in the axial direction, and a vertical concave portion 217 that is recessed in the side wall direction of the housing 1 is formed. The upper portion of the vertical recess 217 is open, and the buried rebar 218 is located. As will be described later, the vertical frame 210 of the bracket 21 is located in the gap between the protrusion step portion 110 on both sides of the side wall 11 of the housing 1, the side wall of the housing 1 ( 11) The protruding connecting bar 117 installed at the side is positioned in the vertical recess 217 of the vertical frame 210.

On the other hand, the cutout step 26 is formed in the side surface of the upper plate 20 that is connected to the housing 1 upper plate, that is, the inner surface of the upper plate 20 in the axial direction. The cutting step 26 may be formed by cutting the upper edge. Since the cutting step portion 26 is formed on the inner surface of the upper plate 20 as described above, the vertical frame 210 of the bracket 21 is fitted in the gap between the protrusion step portions 110 on both sides of the housing 1. When positioned, the cutting step portion 26 of the upper plate 20 and the projecting step portion 110 of the housing 1 meet each other, whereby the cutting step portion 26 and the upper portion of the projecting step portion 110. This creates a space filled with filler such as non-condensed concrete or non-condensed mortar. In the portion where the cutting step portion 26 is formed, the second coupling reinforcing bar 25 protrudes from the upper plate 20 in the direction of the housing der 1 and is positioned above the cutting step portion 26, and the housing der 1 The first coupling reinforcement 115 is also protruded from the side of the) to be positioned above the protruding step portion 110, the filler is to be filled in the upper portion of the cutting step portion 26 and the protruding step portion (110). At this time, the first coupling reinforcement 115 and the second coupling reinforcement 25 is embedded in the filling material is fixed.

Next, a method of constructing a box girder bridge according to the present invention by combining the housing girder 1 and the cantilever unit 2 as described above will be described.

After installing the housing 1 on the pier, the cantilever portion 2 made of the precast concrete member having the structure as described above is coupled to both sides of the housing perpendicular to the axial direction of the housing 1. In detail, the lower end of the vertical frame 210 of the bracket 21 is supported by the lower protrusion 120 protruding from the lower outer surface of the side wall 11 of the housing 1, and at the same time, the protrusions are located at the top of both sides of the housing 1. The cantilever part 2 is installed on both sides of the main body 1 so that the vertical frame 210 is inserted and positioned at the interval between the stepped parts 110.

8 and 9 respectively show a schematic perspective view showing the state in which the cantilever part 2 is assembled on both sides of the housing 1 by the temporary fixing device 4 and a schematic front view in the axial direction. In the present invention, the lower end of the vertical frame 210 of the bracket 21 is supported on the lower protrusion 120 of the housing 1, the upper end of the vertical frame 210 is projected step portion 110 of the housing (1) In the state sandwiched between the gap, the vertical concave portion 217 of the vertical frame 210 is filled with a filling material such as non-condensed concrete, with the cutting step 26 and the housing (1) of the top plate 20 together. In the space above the protruding step portion 110) of the filling material is to be filled and cured. Therefore, the lower end of the vertical frame 210 is placed and supported on the lower protrusion 120 and the upper portion of the vertical frame 210 is inserted into the gap between the protrusion steps 110 until the filler is cured. do. To this end, the temporary fixing device 4 may be used in the present invention. As shown in FIGS. 8 and 9, the temporary fixing device 4 is formed on the upper surface of the housing 1, which is made of a beam member extending in the axial direction perpendicular to the housing. 8 and 9, reference numeral 41 denotes a temporary support 41 placed on the upper surface of the housing 1 to support the temporary fixing device 4.

In the state where the lower end of the vertical frame 210 is placed and supported by the lower protrusion part 120 and the upper part of the vertical frame 210 is fitted in the gap between the protrusion stepped parts 110, by using the vertical hanger member 42. The cantilever portion 2 is suspended from the temporary fixing member 4. That is, the upper end of the hanger member 42 made of a rod member or the like is fixed to the temporary fixing device 4, and the lower end of the hanger member 42 is fixed to the cantilever part 2, thereby allowing the cantilever part 2 to be fixed. ) Is suspended to the temporary fixing device (4) to maintain the position of the cantilever portion (2). The upper end of the hanger member 42 may be fixed to the temporary fixing member 4 by a method such as passing through the temporary fixing device 4 and then coupling with a nut. In addition, the lower end of the hanger member 42 may also be fixed to the cantilever portion 2 by penetrating the upper plate 20 of the cantilever portion 2 or penetrating the horizontal frame 211 with a nut or the like. Can be. Although not shown in the drawings, as an alternative embodiment, a ring member is installed on the upper surface of the upper plate 20 to bind the lower end of the hanger member 42 with the ring member to couple the cantilever part 2 and the hanger member 42. It may be. In this way, a plurality of hanger members 42 are installed, and the cantilever part 2 is attached to the housing 1 while the cantilever part 2 is suspended to the temporary fixing device 4, and the vertical concave part 217 is filled with non-condensed concrete. Filling the filling material in the space above the cutting step portion 26 of the upper plate 20 and the projecting step portion 110 of the housing (1). FIG. 10 is a schematic perspective view illustrating a state in which the cantilever portion 2 is coupled to both sides of the dwelling perpendicular direction of the housing 1 and the filling material 60 is filled.

As described above, in the vertical concave portion 217, one end of the reinforcing bar 218 is embedded in the vertical frame 210 is protruding, and one end is embedded in the housing (1) protruding connecting reinforcement 117 is also protruded into the vertical recess 217 is located. In this state, when the filler is filled and cured in the vertical recess 217, the buried rebar 218 and the protruding connecting bar 117 are embedded in the filler to exert an anchor function, so that the vertical frame 210 is housed. It is firmly integrated in (1). That is, the bracket 21 and the cantilever part 2 itself having the same are firmly integrated with the housing 1.

In addition, the second coupling reinforcing bar 25 protrudes from the upper plate 20 in a space above the cutout step 26 and the protruding step part 110, and is further provided from the upper plate of the housing 1. One coupling reinforcement 115 is also protruded. In this state, when the filler 60 is filled in the space between the cutting step part 26 and the protruding step part 110, the first coupling bar 115 and the second coupling bar 25 are embedded in the filler. By being fixed, the bracket 21 and the cantilever part 2 having the same are integrally coupled with the housing 1 more firmly.

On the other hand, as described above, since the top plate 20 of the cantilever portion 2 has a certain length in the axial direction, the housing 1 has a plurality of cantilever portions 2 in the axial direction in the axial direction of the bridge. ) Are arranged continuously. At this time, the coupling between the upper plate 20 of the cantilever part 2 disposed adjacent to the axial direction should be made. FIG. 11 is a schematic partially enlarged perspective view of the circle A portion of FIG. 10, which is shown for convenience for the filler 60 not yet filled.

As shown in FIG. 11, a cutout portion 29 is also formed in the axial direction between the upper plates 20 of the cantilever portions 2 disposed adjacent to each other in the axial direction, and the longitudinally arranged longitudinally in the upper plate 20. The ends of the direction reinforcing bars 55 are respectively exposed to the cutouts 29, and the cutouts 29 are filled with a filler such as non-condensed concrete so that the upper plate 20 of the cantilever part 2 is integrally formed. can do. In FIG. 11, reference numeral 28 denotes a spacer 28 sandwiched between the upper plates 20, and reference numeral 27 denotes a sealing member 27 applied on the spacer 28 to close the gap between the upper plates 20. .

Figure 12 shows a schematic perspective view of a bridge superstructure according to the invention completed by a PSC box girder, as described above, mounting the cantilever part 2 on both sides of the ridge perpendicular to the housing 1 After the cantilever portion 2 and the housing der 1 are integrally combined using the filling material, both the temporary fixing member 4 and the hanger member 41 are removed, and the housing der 1 and the housing as shown in FIG. 12. On the upper surface of the cantilever part 2, the pavement 80, the central separator 81, and the barrier wall 82 are installed to complete the superstructure construction of the bridge.

Next, another embodiment of the present invention will be described with reference to FIGS. 13 to 18. FIG. 13 is a schematic perspective view illustrating a state in which a cantilever unit is assembled to a housing header corresponding to FIG. 2, and FIG. 14 is a schematic perspective view of the housing in the embodiment shown in FIG. 13. FIG. 15 is a schematic perspective view of the cantilever part applied to the embodiment shown in FIG. 13 as a view corresponding to FIG. 4.

In the following description of another embodiment of the present invention with reference to FIGS. 13 to 15, the same components as those shown in FIGS. 2 to 4 are denoted by the same reference numerals, and repeated descriptions thereof will be omitted. Focus on the configuration. In the case of the embodiment shown in Figs. 13 to 15, the difference from the embodiment shown in Figs. A cutting step 111 is formed to protrude upwardly from the protrusion step portion 110 of the housing der 1, and a cutting step is formed on the inner surface of the upper plate 20 of the cantilever unit 2, that is, the side of the housing der 1 direction. Instead, the down latching jaw 201 is formed.

As shown in detail in FIG. 14, the protruding step portion 110 of the housing der 1 is formed with an upward locking step 111 protruding upward at an end portion of the cantilever portion 2 direction. On the other hand, on the inner surface of the top plate 20 of the cantilever part 2 is formed a downward locking projection 201 protruding downward as shown in FIG.

FIG. 16 is a front view corresponding to FIG. 9, and a front view showing a state in which the cantilever portion 2 is coupled to both sides of the housing 1. As described above, the upward stepped jaw 111 is formed at the protrusion step part 110 of the housing der 1, and the downward stopped step 201 is formed at the inner surface of the upper plate 20 of the cantilever part 2. When the cantilever part 2 is coupled to both sides of the housing 1, as shown in FIG. 16, the downward locking step 201 is positioned inside the upward locking step 111 so that the upward locking step ( 111 and the down stopper 201 is engaged with each other. In the present embodiment, since the lower projection 120 is not formed on the outer surface of the side wall 11 of the housing der 1, the upper locking jaw 111 and the lower locking jaw 201 are engaged with each other and the cantilever at the same time. The vertical frame 210 of the unit 2 is in direct contact with the outer surface of the side wall 11 of the housing 1. According to such a structure, the cantilever part 2 can hold the position on both sides of the housing | casing 1, even without the temporary fixing apparatus 4. As shown in FIG.

17 and 18 are perspective views corresponding to FIGS. 10 and 12, respectively, as shown in FIG. 16, with the cantilever portion 2 installed on both sides of the housing 1 without the temporary fixing device 4. As shown in FIG. 17, the first coupling is formed between the upper part of the protrusion step part 110 and the inner surface of the upper plate 20 of the housing der 1 to protrude upward from the protrusion step part 110. The second reinforcing bar 25 protruding to the inner surface of the reinforcing bar 115 and the upper plate 20 is embedded in the filler 60, and subsequently shown in Figure 18, the housing 1 and the cantilever portion 2 On the upper surface of the pavement 80, the central separator 81, and the protective wall 82 is installed to complete the superstructure construction of the bridge.

In the present invention as described above, the cantilever portion 2 is prefabricated with a precast concrete member in a structure in which the upper plate 20 is supported by the bracket 21, and is coupled to the housing 1. Unlike the prior art, in which the slab of the cantilever portion is joined by a strut, the lower surface of the upper plate 20 is supported by the bracket 21, so that the support area is widened and the stress concentration can be minimized accordingly. It is possible to greatly reduce the risk of cracks and the like.

In particular, since the upper plate 20 of the cantilever portion 2 is supported by the bracket 21 as described above, even if the length of the cantilever portion 2 increases in the perpendicular direction of the axial direction of the cantilever portion 2, prestressing is performed in the upper plate 20 of the cantilever portion in the direction of the axial angle. There is no need to add, and construction costs can be reduced accordingly.

In addition, according to the present invention can reduce the weight of the PSC box girder, and the amount of the tension material required to introduce prestress in the axial direction can also be reduced to improve the workability and economics.

In the prior art, since the slab, which is the upper plate of the cantilever portion, is supported by a bar-shaped strut, the moment and shear force in the perpendicular direction of the axial axis are generated, and the slab of the cantilever portion must be reinforced not only with reinforcing steel but also with tension material to resist such moment and shear force. . However, in the present invention, the slab, which is the upper plate of the cantilever portion, is supported by the bracket on three sides or four sides at the bottom of the slab, and the precast bracket bears the cross-sectional force acting on the slab. Reinforcement with reinforcing bars is sufficient only at the spacing provided, and a separate axial tension reinforcement for the top plate is not necessary. Therefore, it is possible to reduce the cost required to be economical construction.

In addition, in the present invention, since the cantilever part is pre-fabricated and assembled to the housing, the cantilever part is no longer required for installing the cantilever part and installing the cantilever part, thereby reducing the construction cost and reducing the air.

1: dwelling More
2: cantilever section

Claims (5)

A housing (1) having a box-shaped cross section consisting of a side wall (11), an upper plate (12), and a lower plate (13), and a protruding step portion (110) protrudes from an upper surface of the side wall (11) to form a gap in the axial direction. Spaced apart, the first coupling reinforcement 115 protrudes upward from the protruding step portion 110 from the upper plate 12, and exists in the axial direction between the protruding step portions 110. In the outer surface of the side wall (11) to produce a housing (1) to have a configuration in which the protruding connecting reinforcement (117) is installed and installed between the piers and piers or between piers and shifts;
The cantilever part 2, in which the upper plate 20 and the bracket 21, which are manufactured in the form of slab, is integrally manufactured, is manufactured by using a precast concrete member, and the bracket 21 is a vertical frame 210 and a horizontal frame 211. And an inclined frame 212, the horizontal frame 211 is integrated with the upper plate 20, and the vertical frame 210 has a vertical recess 217 in the sidewall direction of the housing 1. Is formed, the vertical recess 217 is a buried rebar 218 is located, the cutting step portion 26 is formed on the side of the upper plate 20 to be connected to the upper plate of the housing (1) Producing a cantilever portion (2) of the configuration in which the second coupling reinforcing bar (25) protrudes in the housing direction above the cutting step portion (26);
Installing each of the cantilever portions (2) on both sides of the perpendicular direction of the housing (1) such that an upper portion of the vertical frame (210) is sandwiched between the axial gaps of the protruding steps (110); And
The buried rebar 218 and the protruding connecting rebar 117 are positioned in the vertical recess 217, and the cutting step 26 and the protruding step 110 face each other, and the first coupling is disposed thereon. In the state where the reinforcing bar 115 and the second coupling reinforcing bar 25 is located, the filling material in the interior of the vertical recess 217, and in the upper space of the cutting step 26 and the projecting step 110, respectively. By filling the hardened, the cantilever portion (2) comprising the step of coupling the cantilever portion on both sides of the housing perpendicular to each other in the axial direction, respectively, to manufacture a superstructure consisting of a PSC box girder to bridge construction Construction method.
The method of claim 1,
When the cantilever part 2 is installed on both sides of the housing shaft 1 in the axial direction perpendicular to each other, a temporary fixing device 4 composed of beam members installed in the axial direction perpendicular to the upper plate of the housing body 1 is installed. ;
In the state where the vertical frame 210 is fitted in the gap between the protruding step portion 110, the upper end of the hanger member 42 is fixed to the temporary fixing device 4 by fixing, the hanger member 42 A bridge construction method, characterized in that the lower end of the cantilever part (2) is fixed to the cantilever part (2) by holding the cantilever part (2).
The method of claim 1,
A protruding stepped portion 111 protruding upward from an end portion of the housing step 1 in the direction of the cantilever portion 2;
On the inner surface of the top plate 20 of the cantilever part 2 is formed a downward locking projection 201 protruding downward;
When the cantilever part 2 is installed on both sides of the housing perpendicular to the orthogonal direction of the housing 1, the vertical frame 210 is fitted in the gap between the protruding steps 110, and the upward locking step 111 The downward locking step 201 is caught inside the vertical frame 210 of the cantilever part 2 is in close contact with the outer surface of the side wall 11 of the housing 1, the cantilever on both sides of the housing 1 Bridge construction method characterized in that the position of the portion (2) is maintained.
It has a box-shaped cross section consisting of the side wall 11, the upper plate 12 and the lower plate 13, the protruding step portion 110 is protruded on the outer surface of the side wall 11 is formed long at intervals in the axial direction, The first coupling reinforcement 115 protrudes upward from the protruding step portion 110 from the upper plate 12, and the outer surface of the side wall 11 at an interval in the axial direction between the protruding step portions 110. It has a housing (1) of the configuration in which the protruding connecting reinforcement 117 is installed;
The cantilevered upper plate 20 and the bracket 21 manufactured in the form of slab are made of a precast concrete member in which the bracket 21 is integrated, and the bracket 21 is a vertical frame 210, a horizontal frame 211 and an inclined frame ( 212, the horizontal frame 211 is integrated with the upper plate 20, and the vertical frame 210 has a vertical recess 217 recessed in the side wall direction of the housing 1. The buried rebar 218 is positioned at the vertical recess 217, and a cutout step 26 is formed at a side of the upper plate 20 to be connected to the upper plate of the housing 1. And a cantilever portion 2 having a configuration in which the second coupling reinforcing bar 25 protrudes in the direction of the housing above the cutting step portion 26;
The cantilever portions 2 are respectively provided on both sides of the perpendicular direction of the housing 1 so that the upper portion of the vertical frame 210 is interposed between the gaps of the protrusion steps 110. The buried rebar 218 and the protruding connecting bar 117 are positioned in the recess 217, and the cutting step 26 and the protruding step 110 face each other so that the first coupling bar ( 115 and the second coupling reinforcement 25 is located, the filling material is filled in the interior of the vertical recess 217, and the upper space of the cutting step portion 26 and the projecting step portion 110, respectively. Bridge having a superstructure made of a PSC box girder, characterized in that the cantilever portion (2) by being cured has a configuration in which the cantilever portion (2) is integrally coupled to both sides of the dwelling perpendicular to the housing (1).
5. The method of claim 4,
A protruding stepped portion 111 protruding upward from an end portion of the housing step 1 in the direction of the cantilever portion 2;
On the inner surface of the top plate 20 of the cantilever part 2 is formed a downward locking projection 201 protruding downward;
When the cantilever part 2 is installed on both sides of the housing perpendicular to the orthogonal direction of the housing 1, the vertical frame 210 is fitted in the gap between the protruding steps 110, and the upward locking step 111 The downward locking step 201 is caught inside the vertical frame 210 of the cantilever part 2 is in close contact with the outer surface of the side wall 11 of the housing 1, the cantilever on both sides of the housing 1 A bridge having a superstructure made of PSC box girders, characterized in that the position of the secondary (2) is maintained.

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