KR102245334B1 - Girder bridge construction method of prestressed girder - Google Patents

Abstract

The present invention relates to an upper girder in which a compressive force is introduced by a stranded wire, and more specifically, a reinforcing bar is placed on the upper part of the girder, and then the tension member of the girder is tensioned. The present invention relates to an upper girder capable of introducing additional prestress by using a reinforcing bar capable of introducing additional prestress, and a method of constructing a girder bridge using the same.
An upper girder capable of introducing additional prestress using a reinforcing bar according to the present invention includes a girder provided with a tension member; A fixing plate fixed to the upper part of the girder in the longitudinal direction of the girder and having a through hole; A reinforcing bar inserted into and installed through the through holes of the fixing plates, the reinforcing bars fixed at both ends of the fixing plates located at both ends, and shorted between any two fixing plates; A connection disassembly tool surrounding the end of the shorted reinforcing bar and selectively connecting or dismantling the shorted reinforcing bar; It characterized in that it includes.

Description

Upper girder that can introduce additional prestress using reinforcement and construction method of girder bridge using it {GIRDER BRIDGE CONSTRUCTION METHOD OF PRESTRESSED GIRDER}

The present invention relates to an upper girder in which a compressive force is introduced by a stranded wire, and more specifically, a reinforcing bar is placed on the upper part of the girder, and then the tension member of the girder is tensioned. The present invention relates to an upper girder capable of introducing additional prestress by using a reinforcing bar capable of introducing additional prestress, and a method of constructing a girder bridge using the same.

In general, the girders used on the upper part of the bridge include Prestressed Concrete Girder and Prestressed Steel Composite Girder.

The prestressed concrete girder is to introduce prestress to the girder made of concrete by using a tension member to resist its own weight and external force, and the steel composite girder is to be manufactured by compounding steel and concrete, and to introduce prestress to the lower concrete in advance. .

Early prestressed concrete girders and steel composite girders used a method of tensioning only once at the end using a tension member. In this way, if the end of the girder is tensioned only once, if it is designed based on the central part of the girder, the end has a large prestress force without need. Conversely, if excessive force is not introduced to the end of the girder, the prestress force introduced in the center of the girder is relatively reduced. There are shortcomings.

Therefore, in recent years, the tension member is first settled at the end of the girder to first tension, and the tension member is secondarily settled in the inner side spaced a predetermined distance from the first fixing place, thereby solving the conventional problem.

By using this method, it is possible to effectively resist the force of the working member caused by the external force by using the prestress caused by the primary tension and the secondary tension.

However, due to the second tension, additional materials such as tension materials, sheath pipes, and fixtures are consumed, and it acts as a factor that increases the manufacturing cost, and there is a problem that the manufacturing time is increased because a tensioning process must be added.

In addition, excessive tension in the process of tension may cause deformation of the girder, and attention must be paid to tension due to this problem.

KR Registered Patent Publication No. 10-0860796 (2008.09.23)

The present invention was invented to solve the problems as in the prior art.After reinforcing the reinforcement on the upper part of the girder, the tension member of the girder is tensioned, and then a section of the reinforcing bar is short-circuited at a desired point to introduce additional prestress suppressed by the reinforcing bar. The purpose of this is to provide an upper girder capable of introducing additional prestress using reinforcing bars and a method of constructing a girder bridge using the same.

An upper girder capable of introducing additional prestress using a reinforcing bar according to the present invention for achieving the above object,

A girder equipped with a tension member;

A fixing plate fixed to the upper part of the girder in the longitudinal direction of the girder and having a through hole;

A reinforcing bar inserted into and installed through the through holes of the fixing plates, the reinforcing bars fixed at both ends of the fixing plates located at both ends, and shorted between any two fixing plates;

A connection disassembly tool surrounding the end of the shorted reinforcing bar and selectively connecting or dismantling the shorted reinforcing bar; It characterized in that it includes.

In addition, the reinforcing bar is characterized in that it is fixed to the fixing plate by forming a screw thread at the end and fastening the nut.

In addition, the connection disassembly tool,

A tubular body into which reinforcing bars are inserted through the open ends;

A cam-type fastener that is axially coupled to one surface of the body and protrudes into the body according to the rotational position to press the reinforcing bar; It is characterized by consisting of.

In addition, a plurality of through holes of the fixing plate are formed in a lateral direction so that several rows of reinforcing bars are installed.

In addition, the method of constructing a girder bridge using an upper girder that can introduce additional prestress by using reinforcing bars,

Preparing a girder in which the tension member and the fixing plate are installed;

Installing the reinforcing bar through the fixing plate, but fixing both ends to the fixing plate and installing so that one part is short-circuited;

Connecting the short-circuited reinforcing bars by installing a connection dismantling port at the short-circuited portion of the reinforcing bar;

Introducing a prestress by pulling and tensioning a tension member at both anchorages of the girder;

Installing a girder into which the prestress is introduced on the abutment and pier;

Installing a precast deck or formwork for pouring concrete floorboards;

Introducing additional prestress to the girder by shorting the reinforcing bar by releasing the disengagement port;

Reconnecting the shorted reinforcing bars; And

Pouring the floor plate concrete; It characterized in that it includes.

In addition, the method of constructing a girder bridge using an upper girder that can introduce additional prestress by using reinforcing bars,

Preparing a girder in which the tension member and the fixing plate are installed;

Installing the reinforcing bar through the fixing plate, but fixing both ends to the fixing plate and installing so that one part is short-circuited;

Connecting the short-circuited reinforcing bars by installing a connection dismantling port at the short-circuited portion of the reinforcing bar;

Introducing a prestress by pulling and tensioning a tension member at both anchorages of the girder;

Introducing additional prestress by shorting the reinforcing bar by releasing the connection disassembly after time elapses;

Reconnecting the shorted reinforcing bars;

Installing additional prestressed girders on the abutments and piers; And

Pouring the floor plate concrete; It characterized in that it includes.

The upper girder that can introduce additional prestress using the reinforcement according to the present invention and the girder bridge construction method using the same can introduce additional prestress by simply tilting the lever of the disassembly port, so it is possible to quickly and conveniently introduce additional prestress. have.

In addition, even if there is excessive tension in the process of introducing the primary prestress, it has the effect of preventing excessive deformation of the girder because it is suppressed by the reinforcing bar, and since additional prestress can be introduced without additional tensioning a separate tension member. The manufacturing cost is inexpensive and there is an effect that it can be installed quickly.

In addition, if the shorted reinforcing bar is connected, it can be used as the original function of the reinforcing bar, so that the rebar reinforcing process time that must be installed on the floor plate in the future is greatly shortened.

1 is a perspective view showing an upper girder according to a first embodiment of the present invention.
Figure 2 is a front view showing an upper girder according to the first embodiment of the present invention.
3 is a plan view showing an upper girder according to a first embodiment of the present invention.
Figure 4 is an enlarged perspective view of the main part showing the reinforcing bar fixing structure of the present invention.
Figure 5 is an enlarged perspective view of the main part showing a state in which the connection disassembly of the present invention is installed.
Figure 6 is a cross-sectional view showing the installation state of the fixing plate according to the first embodiment of the present invention.
Figures 7a, 7b is a front cross-sectional view and a side cross-sectional view showing a state in which the reinforcement is connected by the connection disassembly of the present invention.
Figures 8a, 8b is a front cross-sectional view and a side cross-sectional view showing a state in which the reinforcing bar is short-circuited by the disconnection tool of the present invention.
Figure 9 is an exemplary view showing a state in which the connecting rod of the present invention is installed.
10 is a flow chart showing the construction process of the girder bridge according to the first embodiment of the present invention.
11A to 11E are process diagrams showing the construction process of the girder bridge according to the first embodiment of the present invention.
12 is an exemplary view showing the working member force of the upper girder according to the present invention.
13 is a perspective view showing an upper girder according to a second embodiment of the present invention.
14 is a front view showing an upper girder according to a second embodiment of the present invention.
15 is a flow chart showing the construction process of the girder bridge according to the third embodiment of the present invention.

Hereinafter, a preferred embodiment of an upper girder capable of introducing additional prestress using a reinforcing bar according to a first embodiment of the present invention and a method for constructing a girder bridge using the same will be described in detail with reference to the accompanying drawings.

1 is a perspective view showing an upper girder according to a first embodiment of the present invention, FIG. 2 is a front view showing the upper girder, FIG. 3 is a plan view showing the upper girder, and FIG. 4 is a reinforcing bar fixing structure. An enlarged perspective view of the main part, FIG. 5 is an enlarged perspective view of the main part showing a state in which the connection disassembly is installed, FIG. 6 is a sectional view showing a fixed plate installation state, and FIGS. 7A and 7B are a front sectional view showing a state in which reinforcing bars are connected by a connection disassembly tool And a side cross-sectional view, FIGS. 8a and 8b are a front cross-sectional view and a side cross-sectional view showing a state in which a reinforcing bar is short-circuited by a connection disassembly tool, and FIG. 9 is an exemplary view showing a state in which the connecting rod is installed.

As shown in these drawings, the upper girder capable of introducing additional prestress using the reinforcing bar according to the first embodiment of the present invention is a prestressed concrete girder equipped with a connection dismantling tool for shorting the reinforcing bars and reinforcing bars of the present invention.

That is, the girder 10 provided with the tension member 11; A fixing plate 20 which is fixed to the upper portion of the girder 10 in the longitudinal direction of the girder 10 and has a through hole 24 formed therein; A reinforcing bar 30 that is inserted into the through hole 24 of the fixing plate 20 and installed through it, and both ends are fixed to the fixing plate 20 at both ends, and a short-circuited between any two fixing plates 20; A connection disassembly tool 40 surrounding the end of the shorted reinforcing bar 30 and selectively connecting or dismantling the shorted reinforcing bar 30; Includes.

And a girder bridge construction method using an upper girder capable of introducing additional prestress using a reinforcing bar according to the present invention, as shown in FIG. 10, a girder preparation step (ST100); Rebar installation step (ST200); A step of installing a connection disassembly port (ST300); Tension material tension step (ST400); Installation of girders on the bridge and pier (ST500); Precast deck or formwork installation step (ST600); Rebar short-circuit step (ST700); Reinforcing bar connection step (ST800); And the concrete pouring and curing step (ST900); Includes.

The girder preparation step (ST100) is a step of preparing the girder 10 in which the sheath tube and the fixing plate 20 are integrated.

The girder 10 is manufactured in the shape and size designed at the time of molding, but the tension member 11 is inserted by embedding a sheath tube therein, and anchorages are installed at both ends of the sheath tube to fix the tension member 11. In addition, the lower part of the fixing plate 20 is embedded in the upper part of the girder 10 and integrated with the girder 10.

The fixing plate 20 is formed vertically on the upper portion of the horizontal portion 21 and the horizontal portion 21 and the horizontal portion 21 that is partially or entirely embedded in the girder 10, as shown in Figs. It is composed of a vertical portion 22 exposed to the outside and a plurality of studs 23 protruding from the lower portion of the horizontal portion 21. The fixing plate 20 has a plurality of through-holes 24 formed at regular intervals in the lateral direction so that the reinforcing bars 30 can be inserted therethrough, and the stud 23 has a large external force in a state where the ends are expanded and buried. Even if this occurs, it should not be removed.

The fixing plate 20 is provided on the upper portion of the girder 10 and maintains a constant distance in the longitudinal direction of the girder 10.

The reinforcing bar installation step (ST200) is a step of inserting and fixing a reinforcing bar in the fixing plate 20 of the girder 10.

Reinforcing bars 30 are inserted into all of the through holes 24 located on the same axis among the plurality of fixing plates 20, and the reinforcing bars 30 are fixed to the fixing plates 20 provided at both ends. The fixing plate 20 and the reinforcing bar 30 are fixed by a nut N as shown in FIG. 4. A thread 31 is formed at the end of the reinforcing bar 30. Then, the nut (N) is fastened to the screw thread 31 of the reinforcing bar 30 exposed to the outside of the fixing plate 20 to be fixed. At this time, the nut (N) may be fastened to the inside of the fixing plate 20 as well, and it may be fastened with the washer (W) inserted therein. The reinforcing bar 30 is only fixed to the fixing plate 20 to which the nut N is fastened, but simply penetrates the remaining fixing plate 20 so that the reinforcing bar 30 is free to move in the axial direction.

The reinforcing bar 30 installed in this way maintains a state in which one part is short-circuited. The short-circuited part may be anywhere, but it is preferable to short-circuit the central part of the reinforcing bar 30. In this case, a short circuit may be achieved by installing one reinforcing bar 30 and then forcibly cutting the center thereof, or simply by inserting two reinforcing bars 30 from both sides to achieve a short-circuited state.

In this way, by installing the reinforcing bars 30 on all the fixing plates 20, several rows of reinforcing bars 30 are installed on the upper part of the girder 10.

In the step of installing the connection disassembly tool (ST300), the connection disassembly port 40 is installed on the reinforcing bar 30 in the short-circuited area.

The connection disassembly tool 40 is composed of a tubular body 41 and a fastener 43 for tightening the reinforcing bar 30 located inside the body 41 as shown in FIGS. 7A to 8B. The body 41 is formed in a tubular shape with both ends open, and a manipulation hole 42 penetrating in and out of the center is formed. The fastener 43 is coupled to the shaft (S) on one surface of the body 41, and as it rotates, the cam part 44 protrudes and protrudes into the body 41 through the manipulation hole 42, and at one end of the cam part 44. It is formed integrally and consists of a lever 45 protruding to the outside of the body 41.

The connection disassembly port 40 is installed at the portion of the shorted reinforcing bar 30, and the reinforcing bar 30 is inserted from both open ends of the body 41 so that the shorted portion of the reinforcing bar 30 is It should be located in the center.

And the inner surface of the body 41 and the cam portion 44 of the fastener 43 forms a concave-convex 46 through which the nodal rib 32 of the reinforcing bar 30 is engaged, and the cam portion by the operation of the lever 45 When 44 presses the reinforcing bar 30, the rib 32 of the reinforcing bar 30 is caught by the unevenness 46 and the shorted reinforcing bars 30 are integrated by the connection and disassembly tool 40. On the contrary, when the lever 45 is rotated in the opposite direction, the cam portion 44 that was pressed is separated from the reinforcing bar 30 so that both reinforcing bars 30 are in a short-circuited state.

Here, it is revealed that a rubber plate can be installed on the inner surface of the body 41 and the cam portion 44 of the fastener 43 to be in close contact with the reinforcing bar to improve the adhesion.

The connection disassembly port 40 as described above is installed at all short-circuited parts of the reinforcing bar 30, and the cam part 44 presses the reinforcing bar 30 by rotating the lever 45 to remove the short-circuited reinforcing bar 30. All are united.

All of the levers 45 may be integrated by a connecting rod 47 as shown in FIG. 9. The lever 45 and the connecting rod 47 are integrated by fastening pins, bolts, and nuts. Therefore, when any one of the levers 45 or the connecting rod 47 is operated, all the levers 45 operate together.

The tension member tension step (ST400) is a step of pulling the tension member 11 from the end of the girder 10 to tension, as shown in FIG. 11A.

Prestress is first introduced into the girder 10 by tensioning the tension member 11 inserted in the sheath tube. In this process, the prestress suppressed by the reinforcing bar 30 installed at the top is introduced. Here, even if the tension is excessive, a compressive force above a certain value is not introduced by the reinforcing bar 30 at the top. Accordingly, it is possible to prevent deformation of the girder 10 due to excessive tension. On the other hand, the reinforcing bar 30 is also naturally in a tension state.

Next, as shown in FIG. 11B, a step (ST500) of installing the girder 10 into which the pre-stress is introduced is installed on the abutment and on the pier proceeds.

And it goes through the step (ST600) of installing a precast deck or formwork for pouring the floor plate concrete 50. At this time, loss of tension occurs due to the load of the precast deck or formwork with the passage of time.

In the reinforcing bar short-circuit step (ST700), when a tension loss occurs, the connection disassembly port 40 is operated to short-circuit the connected reinforcing bar 30 as shown in FIG. 11C, thereby introducing additional prestress suppressed by the reinforcing bar 30. It is a step to do.

That is, by short-circuiting the reinforcing bar 30 integrated by the connection disassembly port 40, the cam part 44 that was pressing the reinforcing bar 30 by rotating the lever 45 is moved to one side to release the pressurized state. Then, the integrated reinforcing bar 30 is short-circuited again, and the prestress that was suppressed by the reinforcing bar 30 is additionally introduced. At this time, since the short-circuited reinforcing bar 30 is inserted into the fixing plate 20, a bouncing phenomenon is prevented.

And all the levers 45 are operated at the same time by the connecting rod 47 so that all the connection and disassembly ports are operated at the same time, so that all the reinforcing bars 30 are short-circuited. This is to prevent the tensile force from being concentrated on the reinforcing bar 30 to be short-circuited later when sequentially shorting.

The reinforcing bar connection step ST800 is a step of reconnecting the shorted reinforcing bar 30. At this time, as shown in Fig. 11d, in a state in which a separate reinforcing bar 30 is superimposed on both short-circuited reinforcing bars 30, integrated by wire 33 or welding, or using the connection disassembly tool 40 of the present invention. And reconnect the shorted reinforcing bars. Of course, it should be noted that commercially available couplers can also be used. When using a separate reinforcing bar 30 or a coupler, there is an advantage of being able to continuously recycle the used connection disassembly 40 to another girder 10.

By connecting the short-circuited reinforcing bars 30 as described above, since there is no need to reinforce a separate reinforcing bar, the reinforcing bar reinforcing process is omitted, thereby reducing the time period.

Finally, by proceeding the step (ST900) of pouring the deck concrete 50 and curing, the construction of the girder bridge using the upper girder capable of introducing additional prestress using reinforcing bars is completed.

As shown in FIG. 12, the girder bridge constructed as described above can effectively resist the force acting by the external force by using the primary tension caused by the tension member and the prestress caused by the short-circuit of the reinforcing bar.

13 is a perspective view showing an upper girder according to a second embodiment of the present invention, and FIG. 14 is a front view showing an upper girder according to the second embodiment of the present invention.

As shown in these drawings, the upper girder according to the second embodiment of the present invention is a steel composite girder equipped with a connection dismantling tool for shorting the reinforcing bars and reinforcing bars of the present invention.

That is, the steel material 10' and the concrete are synthesized to manufacture the girder 10, but the lower flange of the steel material 10' is made to be buried inside the concrete, and the upper flange is exposed to the outside. Then, the sheath tube is embedded in the concrete so that the tension member 11 is inserted, and anchorages are installed at both ends of the sheath tube to fix the tension member 11. In addition, by welding the fixing plate 20 to the upper portion of the girder 10, it is integrated with the girder 10. Here, since the fixing plate 20 is welded to the steel material 10', the horizontal portion 21 is not required, and the lower end of the vertical portion 22 is welded.

Since the reinforcing bar 30 and the connection disassembly tool 40 are the same as in the first embodiment, a description thereof and a description of the construction process will be omitted.

On the other hand, FIG. 15 is a flow chart showing the construction process of the girder bridge according to the third embodiment of the present invention, and is a flow chart showing the construction process of the girder bridge when the reinforcing bars are short-circuited before installing the girders in the abutment and pier.

That is, the girder preparation step (ST100); Rebar installation step (ST200); A step of installing a connection disassembly port (ST300); Tension material tension step (ST400); Rebar short-circuit step after time (ST700); Reinforcing bar connection step (ST800); Installation of girders on the bridge and pier (ST500); Concrete pouring and curing step of the floor plate (ST900); Includes.

When the tension loss occurs as a predetermined time elapses after the tension member tension step (ST400), the prestress that has been suppressed by the reinforcing bar 30 through the rebar short-circuit step (ST700) is additionally introduced. Next, after connecting the reinforcing bars 30 through the reinforcing bar connection step (ST800), the girder installation step (ST500) is performed on the abutment and pier, and the construction is completed through the concrete pouring and curing step (ST900) of the floor plate.

The present invention introduced additional prestress by shorting the reinforcing bar 30 after the first tension using the tension member 11, but after the first tension by the first tension member 11, the second tension due to the second tension member 11 It should be noted that this is possible, and then prestress by shorting the reinforcing bar 30 can be additionally introduced.

In addition, the present invention introduces additional prestress using the reinforcing bar 30, but it is revealed that a steel bar having a higher allowable tensile strength than the reinforcing bar can be used when a larger amount of additional prestress is introduced.

Although described above with reference to preferred embodiments of the present invention, those skilled in the art will be able to variously modify and change the present invention within the scope not departing from the spirit and scope of the present invention described in the following claims. You will understand that you can.

10: girder 10': steel 11: tension material
20: fixed plate 21: horizontal portion 22: vertical portion
23: stud 24: through hole 30: reinforcement
31: thread 32: rib 33: wire
40: heat connection dismantling part 41: body 42: operation hole
43: fastener 44: cam portion 45: lever
46: irregularities 47: heat coupling zone 50: floor plate concrete
N: Nut S: Shaft W: Washer

Claims (6)

Preparing the girder 10 in which the tension member 11 and the fixing plate 20 are installed (ST100);
Installing the reinforcing bar 30 through the fixing plate 20 but fixing both ends to the fixing plate 20 and installing so that any one portion is shorted (ST200);
Step of connecting the shorted reinforcing bar 30 by installing the connection disassembly port 40 to the shorted portion of the reinforcing bar 30 (ST300);
Introducing prestress by pulling the tension member 11 from both anchorages of the girder 10 to tension (ST400);
Installing the girder 10 in which the pre-stress has been introduced over the abutment and pier (ST500);
Step of installing a precast deck for pouring concrete floor plate (ST600);
Introducing additional prestress by shorting the reinforcing bar 30 by loosening the connection disassembly port 40 (ST700);
Reconnecting the shorted reinforcing bar 30 (ST800); And
Pouring the floor plate concrete 50 (ST900); Construction method of a girder bridge using an upper girder capable of introducing additional prestress using a reinforcing bar, characterized in that it includes.
Preparing the girder 10 in which the tension member 11 and the fixing plate 20 are installed (ST100);
Installing the reinforcing bar 30 through the fixing plate 20 but fixing both ends to the fixing plate 20 and installing so that any one portion is shorted (ST200);
Step of connecting the shorted reinforcing bar 30 by installing the connection disassembly port 40 to the shorted portion of the reinforcing bar 30 (ST300);
Introducing prestress by pulling the tension member 11 from both anchorages of the girder (ST400);
Step of introducing additional prestress by shorting the reinforcing bar 30 by loosening the connection disassembly port 40 after the time has elapsed (ST700);
Reconnecting the shorted reinforcing bar 30 (ST800);
Installing the girder 10 to which the additional prestress has been introduced over the abutment and pier (ST500); And
Pouring the floor plate concrete 50 (ST900); Construction method of a girder bridge using an upper girder capable of introducing additional prestress using a reinforcing bar, characterized in that it includes.
The method of claim 1 or 2, wherein the reinforcing bar (30) forms a thread (31) at the end and is fixed to the fixing plate (20) by tightening a nut (N). Construction method of girder bridge using upper girder possible.
[3] The upper part of claim 1 or 2, wherein a plurality of through holes (24) of the fixing plate (20) are formed in a lateral direction so that several rows of reinforcing bars (30) are installed. Construction method of girder bridge using girder.
The method according to claim 1 or 2, wherein the connection disassembly tool (40),
A tubular body 41 into which reinforcing bars are inserted through the open ends;
The shaft (S) is coupled to one surface of the body (41) and is formed integrally with one end of the cam part 44 and the cam part 44 protruding and protruding into the body 41 according to the rotational position to press the reinforcing bar 30 A fastener 43 composed of a lever 45 protruding to the outside of the body 41; Construction method of a girder bridge using an upper girder capable of introducing additional prestress using a reinforcing bar, characterized in that it includes.
The method of claim 5, wherein all the levers (45) are all integrated by the connecting rod (47), and when any one of the levers (45) or the connecting rod (47) is operated, all the levers (45) operate at the same time and all reinforcing bars (30). ) A method of constructing a girder bridge using an upper girder capable of introducing additional prestress using a reinforcing bar characterized by being short-circuited.

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