KR20130030109A - Method of constructing prestressed girder using segmented girder and fixing structure used therein - Google Patents

Abstract

PURPOSE: A manufacturing method of a prestressed girder for a bridge using a segmented girder and a mounting structure thereof are provided to correspond to the stress condition which has effect on a bridge during the use of the bridge by adopting compression prestress deferent from each section to the segmented girder which is longitudinally connected. CONSTITUTION: A segmented girder includes a hollow unit, an accommodation unit and a concrete girder equipped with an anchorage device. A manufacturing method of a prestressed girder(100) for a bridge using a segmented girder comprises the following g steps. A tendon(50) is installed on the accommodation unit of the segmented girder after multiple segmented girders are arranged in a longitudinal direction. The compression prestress is applied to the tendon by using the anchorage to make the tendon settled on both sides of a first segmented girder(110) after the tendon is strained. The segmented girders are connected by adopting the process of straining, mounting and prestressing successively to a nearest-neighboring segmented girder to the first segmented girder as a start.

Description

Method for manufacturing prestressed girder for bridges using segmental girder and fixing structure used therein {METHOD OF CONSTRUCTING PRESTRESSED GIRDER USING SEGMENTED GIRDER AND FIXING STRUCTURE USED THEREIN}

The present invention relates to a method for manufacturing a bridge girder using a segmental girder and a fixing structure used therein. More particularly, the present invention relates to a stress girder which acts in common in bridges in making a long span girder by connecting a segmented girder. The present invention relates to a method for manufacturing a bridge girder using a segmental girder, in which the introduction process of the prestress is simplified while the prestress is introduced, a prestress girder produced thereby, a bridge manufactured using the same, and a fixing structure used therein.

In general, precast concrete girder manufactures precast concrete blocks in a factory, then transports the precast concrete blocks to the site to arrange the precast concrete blocks in the longitudinal direction, and then to the plurality of longitudinally arranged precast concrete blocks. Compression prestress is introduced into a number of precast concrete blocks by inserting a tension member into the sheath tube of the block to fix the tension.

Since the precast concrete girder is constructed in the field using precast concrete blocks made in advance in the factory, it is possible to obtain an advantage of reducing the time required to manufacture the concrete girder on the site. However, when the girder is manufactured using the precast concrete block, the prestress is introduced at a time by connecting a plurality of precast concrete blocks by the tension material penetrating in the longitudinal direction. There was a limit.

The present invention, in order to solve the conventional problems as described above, in the production of the prestress girder by connecting the segment girder, the prestress using the segment girder while introducing such that the compression prestress corresponding to the stress state acting during the common operation of the bridge is distributed. It is an object of the present invention to provide a method for manufacturing a prestress girder for bridges, and a prestress girder constructed thereby.

Another object of the present invention is to introduce different compressive prestresses in various sections as one tension member, and to introduce prestresses corresponding to loads applied in common.

In addition, an object of the present invention is to produce a prestress girder in a short time by simplifying the process in the introduction of different sizes of prestress according to the position of the girder.

In addition, another object of the present invention is to enable the construction of a long span bridge such as a bicycle and sidewalk bridge or a railway bridge using the prestress girder manufactured as described above.

In addition, the present invention is to introduce a different compression prestress for each section by tensioning one tension member several times, even if the tension-tensioned tension member is re-tensioned with the compression prestress is introduced for some sections, the compression prestress is introduced section It is another object to maintain the fixing state of the fixing unit installed on both sides of the.

The present invention has been derived to achieve the above object, a plurality of receiving portions that can be arranged in the longitudinal direction of the tension member is formed a plurality of including a first segment girder and a second segment girder in which the receiving portion is aligned in the longitudinal direction A segment girder arrangement step of preparing a segment girder; A tension member installation step of installing a tension member in the plurality of accommodation portions of the segment girder arranged in a longitudinal direction; After tensioning the first tension member, which is a part of the tension member, anchorages are fixed to both ends of at least one of the first segment girder of the plurality of segment girders, so that the first compression prestress is applied only to the first segment girder by the first tension member. Introducing a first compression prestress; After tensioning a part of the tension member, the second segment is fixed by fixing anchors at both ends of the first segment girder and at least one second segment girder longitudinally adjacent to the first segment girder among the plurality of segment girder. A second compression prestress introduction step of introducing a second compression prestress into the girder; It provides a manufacturing method of a prestressed girder to include.

This is achieved by aligning the segmental girders with a plurality of receiving sections in which the tension members are accommodated in the longitudinal direction and passing the tension members through the receiving sections of the multiple segment girders, and then tensioning some or all of the tension members installed in the receiving sections, and By introducing the first compression prestress into the first segment girder by fixing it to both sides of the first segment girder, which is part of the first segment girder, and then tensioning some or all of the tension member to the end of the second segment girder adjacent to the first segment girder. In order to manufacture a prestress girder for introducing a second compression prestress to the second segment girder.

In this way, the first compression prestress is introduced into a part of the first segment girder among the plurality of segment girders, and then the second compression prestress is introduced into the second segment girder adjacent to the first segment girder, thereby longitudinally. It is possible to introduce different compression prestresses for each section in a plurality of segmented girders connected.

In addition, since the joint girder is naturally fixed in the longitudinal direction while introducing compression prestress to a plurality of segment girder, the process of connecting the segment girder and the process of introducing the prestress are much simpler than the conventional girder fabrication method. Advantageous effects can be obtained.

Furthermore, the tension member for introducing the second compression prestress to the second segment girder may use the first tension member. That is, the tension member introducing the second compression prestress may include at least a portion of the first tension member. Therefore, even when the tension members are arranged in one row, compression prestresses of different sizes can be introduced into the first segment girder and the second segment girder, respectively.

At this time, according to another embodiment of the present invention, the tension force for introducing the second compression prestress is preferably tensioned to a smaller magnitude than the tension force for introducing the first compression prestress. Through this, it is possible to prevent the fixing unit in which the first compression prestress is introduced to be released.

According to another embodiment of the invention, the tension material for introducing the second compression prestress is made of a second tension material that does not include the first tension material, the second compression to the first segment girder and the second segment girder Prestress may be introduced. In general, since a plurality of tension members are arranged in the receiving portion of the segmental girder, the second compression prestress may be introduced into a second tension member other than the first tension member without using the first tension member.

That is, the present invention can introduce the compression prestress by section using the tension material for each segment girder, and can also introduce the compression prestress of the same or different size to another segment girder by using the tension material which introduced the compression prestress to some segment girder. And a tension member that did not introduce compression prestress to some segment girders, may introduce compression prestresses of the same or different sizes to other segment girders.

At this time, the second segment girder may be arranged on both sides in the longitudinal direction of the first segment girder, and may be arranged symmetrically about the first segment girder. Since the largest tensile stress acts on the span center of the bridge, when the first segment girder is positioned at the center of the span, the first compression prestress is introduced to the first segment girder, and the center of the first segment girder is This is to introduce a smaller second compression prestress to the second segment girder on both sides in the longitudinal direction so that the prestress corresponding to the load acting during actual use can be introduced.

Further, after the first segment girder and the second segment girder are tensioned with a part of the tension member, anchorages are provided at both ends of at least one third segment girder adjacent to both sides of the second segment girder in both longitudinal directions of the plurality of segment girder. It may further include a third compression pre-stress introduction step of introducing a third compression pre-stress to the third segment girder by fixing the. In this way, while extending the second segment girder, the third segment girder, and the fourth segment girder on both sides centering on the first segment girder, the compression prestress of different size is introduced for each segment girder to meet the common load. Compression prestress is introduced.

Furthermore, the present invention, after installing the tension member in advance in the receiving portion of the segment girder, and then strain the tension material such as the first tension material, the second tension material and then settled for each section of the segment girder to introduce a compression prestress, Even if the installation process is performed only once, different compression prestresses can be introduced for each segment of the desired segmental girder, but the simple construction process is similar to the conventional construction process in which the same compression prestress is introduced throughout the girders. Can be obtained.

Meanwhile, the accommodating part in which the tension member is installed may be formed as a through hole penetrating each segment girder in the longitudinal direction, and may be formed in a shape that protrudes outward from a cross section of the segment girder so that the tension member may be fixed while passing.

The segmental girder may be formed of a concrete girder mainly composed of concrete, and the segmental girder may be formed of a steel pipe girder having a web in which a hollow part is provided and a fixing fixture is positioned. The casing concrete may be formed of a synthetic steel girder, or a combination thereof. That is, the present invention can be applied to any segment girder capable of arranging the tension member in the longitudinal direction regardless of the shape and the material of the segment girder.

On the other hand, the first compression prestress introduction step and the second compression prestress introduction step may be carried out on the ground, may be mounted on the bridge for the construction of the bridge, it may be carried out in a state mounted for the bridge on the upper side from the ground. At this time, in order to support the segment girder in the mounted state, a support cable or a temporary holder for supporting the weight of the segment girder may be installed.

When the prestress girder manufactured as described above is connected to the segment girder in close contact with the longitudinal direction by the length of the prestress girder to be manufactured, the tension member installed to penetrate through the plurality of segment girder arranged in the longitudinal direction or to be arranged along the outside thereof. It will cut both ends of the longitudinal direction. This is because the tension member is formed long enough to pass through several segment girder, so that a step of cutting one or both ends of the tension member is required.

On the other hand, the present invention provides a prestress girder manufactured as described above.

On the other hand, according to another field of the invention, the present invention, as a structure of the anchorage used in the manufacturing method, the end of the segment girder in which the anchorage is installed protrudes perpendicularly to the longitudinal direction, the tension material is passed through A web with through holes formed therein; A fixing body arranged in the through hole and having a male thread formed on an outer circumferential surface thereof, and having a wedge receiving hole having an inclined inner surface at its center; A pair of stop washers provided with female threads engaged with the outer circumferential surface of the fixing body to be in close contact with both sides of the web; A wedge member having an inclined surface corresponding to the inclination of the wedge receiving hole on an outer surface thereof, and having a receiving hole for receiving a tension member formed by a strand in a center portion in a penetrating form, and being divided into two or more in the circumferential direction; It provides a fixing structure comprising a position washer that is engaged with the male thread of the fixing body while pressing one surface of the wedge member.

In addition, according to another embodiment of the present invention, the fixing structure, the end of the segment girder in which the fixing device is installed, protrudes perpendicularly to the longitudinal direction, the web formed with a through hole through which the tension member passes; A pair of stop washers provided with a female thread portion engaged with an outer circumferential surface of a tension member formed of a steel rod having a male thread portion formed on an outer circumferential surface thereof and in close contact with both sides of the web; A coupler having a female thread portion engaged with an outer circumferential surface of the tension member to adjust the tension of the tension member at one side of the stop washer; .

Alternatively, according to another embodiment of the present invention, the fixing structure, the end of the segment girder in which the fixing device is installed projecting perpendicularly to the longitudinal direction, the web is formed with a through hole through which the tension member passes; A coupler provided with a female thread engaging with an outer circumferential surface of a tension member formed of a pair of steel rods having a male thread portion formed on an outer circumference thereof, and being in close contact with the outer surfaces of the webs spaced apart from each other to rotate on the tension member so as to be in close contact with the web; A fixing nut having a female threaded portion formed at a central portion thereof to receive the pair of steel bars between the pair of couplers; .

On the other hand, as a fixing structure used in the method of manufacturing the prestressed girder, the present invention is embedded in the end of the segment girder in which the fixing device is installed, the position is fixed, so that the steel rod formed with a male thread on the outer peripheral surface is fastened as a tension member A fixing body having a female screw portion at a central portion thereof and having a fixing plate which is in contact with and supported by an end surface of the segment girder; A coupler having a female threaded portion engaged with a male threaded portion formed on the outer circumferential surface of the steel bar, the central portion being formed at the center portion thereof; Including, the coupler is fixed in position in close contact with the fixing plate provides a fixing structure.

The fixing structure includes a fixing plate embedded in an end portion of the segment girder in which the fixing unit is installed and fixed in position, and provided with a fixing plate that is in contact with the end surface of the girder, and protrudes outwardly in the longitudinal direction of the fixing plate. A fixing body having a protrusion formed therein and a wedge receiving hole formed in a central portion thereof; A wedge member having an inclined surface corresponding to the inclination of the wedge accommodating hole on an outer surface thereof, having an accommodating portion for receiving the tension member in a center portion thereof, and being divided into two or more in the circumferential direction; It may be configured to include a fixing nut for engaging the male thread of the protrusion of the fixing body in contact with one surface of the wedge member to fix the position of the wedge member.

With the above-described fixing structure, the tension member is completely fixed to the segment girder in which the compression prestress is introduced while maintaining the state where the compression prestress is introduced into the segment girder by the tension member. Accordingly, when the fixing structure is installed on the tension member that has already introduced the compression prestress to the segmental girder, even if a larger external force is applied to the segmental girder on which the fixing structure is installed, no additional compression prestress than the compression prestress already introduced is introduced. Thus, the intended compression prestress can be introduced more accurately. In addition, in the segment girder in which the compression prestress is introduced using the fixing structure, the introduction state of the compression prestress is maintained by the fixing structure itself for each region located between the fixing structures. Therefore, it is possible to replace the segmental girder in a state where only a part of the region is released without releasing all of the compression prestress introduced into the prestress girder.

That is, the present invention includes the steps of fixing the tension material passing through the receiving portion of the plurality of segment girder by at least one of the fixing structure to introduce a stepwise compression prestress to the segment girder to produce a prestress girder; A releasing step of releasing the compression prestress introduced only in the area containing the segment girder to be replaced; A replacement step of replacing the segment girder to be replaced with a new segment girder; Introducing compression prestress into a region that includes the replaced segmental girder; It provides a method of replacing the segmented girder of the containing prestressed girder.

This is because the prestress introduced into the segmental girder of one region by the fixing structure is not affected by the prestress introduced into the segmental girder of the other region, and thus, when replacing the segmented girder to be replaced by damage or the like, it is introduced into the prestressed girder. This is to replace some segment girders by releasing only the compression prestress of the area to which the segment girder to be replaced does not release all the compression prestresses.

In this case, the replacement of the segment girder may be performed before the prestress girder is installed in the bridge, but the prestress girder is in the state of being installed in the bridge, and the dismantling step and the replacement step are the prestress girder installed in the bridge. May be done for.

Meanwhile, 'first segment girder', 'second segment girder', and 'third segment girder' described in the present specification and claims are not limited to one segment girder, and two or more segment girder are connected in the longitudinal direction. The segmental girder group will be defined as one that can be made. In addition, the 'tension material' described in the present specification and claims is not limited to a single stranded wire, and two or more steel bars are defined as including a form connected by a coupler.

On the other hand, the present invention provides a prestress girder manufactured by the above method.

In addition, the present invention provides a bridge manufactured by using a prestress girder manufactured by the above method. At this time, the prestress girder is manufactured so that the compression prestress is introduced while closely contacting the segment girder in the longitudinal direction on the ground and is mounted on the pier, or directly attached to the pier or the alternation, or the segment is mounted by the cable above the pier. Compression prestress may be introduced while the girders are in close contact with each other in the longitudinal direction.

As described above, the present invention is a part or all of the tension member provided in the receiving portion after the longitudinal girder having a plurality of receiving portions to accommodate the tension member is aligned in the longitudinal direction and installed by passing the tension member to the receiving portion of the multiple segment girder The first compression prestress is introduced to the first segment girder by tensioning the first segment girder and the fixing unit on both sides of the first segment girder, which is part of the segment girder, and then tensioning part or all of the tension member to the second adjacent to the first segment girder. Provided is a method of manufacturing a prestress girder capable of introducing different compression prestresses to respective segments to a plurality of segment girder connected in the longitudinal direction by fixing at the end of the segment girder, and a prestress girder produced thereby.

Accordingly, the present invention, by the process of connecting the segment girder only by introducing a large pre-stress is introduced in the center portion and a smaller pre-stress is introduced at both ends in order to meet the stress state acting during the common use of the bridge, compressing while implementing the construction convenience Provided are a manufacturing method of a bridge prestress girder capable of adjusting the amount of prestress introduced and a prestress girder produced thereby.

Above all, the present invention naturally connects and fixes the segmental girder in the longitudinal direction while introducing compression prestress to a plurality of segmental girders, so that the process of connecting the segmental girder and the process of introducing the prestress are separated from the conventional girder manufacturing method. An advantageous effect can be obtained in which the process is simplified.

In addition, according to the present invention, as the tension member introducing the second compression prestress includes a part or more of the first tension member, even when the tension members are arranged in one row, the first segment girder and the second segment girder have different sizes. Compression prestress can be introduced, and by compressing a plurality of tension members collectively, compression prestresses introduced for each segment girder can be produced with a differential for each section.

In addition, the present invention not only solves an inefficient prestress introduction problem in which the prestress is introduced at both ends of the span smaller than at the center, but also introduces an unnecessarily large prestress to both ends, and also excessively large compression prestress at both ends of the girder. The problem that causes the damage to the girder can be solved.

Through this, the present invention can easily and quickly produce the prestress girder using the segmental girder, while introducing a compressive prestress corresponding to the stress state acting during common use, more effectively the common load without introducing excessive prestress Will be able to support.

In addition, the present invention provides a fixing device that does not solve the tension state introduced earlier, even if the additional tension force acts more with respect to the tension material introduced pre-stress in the segmental girder of some sections.

On the other hand, the present invention uses a fixing structure that can maintain the introduction state of the compression prestress, when replacing the segment girder to be replaced, the segment to be replaced without releasing all the compression prestress introduced to the prestress girder Only the compression prestress of the area to which the girders belong can be released to obtain the advantageous effect of replacing some segmented girders.

1 is a perspective view showing a configuration of manufacturing the prestressed girders according to the first embodiment of the present invention
2A to 2E are front views sequentially illustrating a method of manufacturing the prestress girder of FIG.
3A to 3D are schematic views sequentially illustrating a method for manufacturing a bicycle and sidewalk bridge using the prestress girder of FIG.
4 is a cross sectional view of FIG. 3d;
5 is a front view showing the configuration of the prestress girder according to the second embodiment of the present invention;
6A and 6B are cross-sectional views taken along the line 6-6 showing a cross section of the girder applicable to the configuration of FIG.
7A to 7C are front views sequentially illustrating a method of manufacturing the prestress girder of FIG.
8 is a perspective view showing the configuration of a prestressed steel pipe girder according to a third embodiment of the present invention;
9 is a cross-sectional view taken along the line XI-XI of FIG. 8
10 is a longitudinal sectional view of the sleeve of FIG.
FIG. 11 is a side view of the web of the steel pipe girder of FIG. 8; FIG.
12 is a longitudinal sectional view of the steel pipe girder of FIG.
13A to 13C are front views sequentially illustrating a method of manufacturing the prestress girder of FIG.
14A to 14C show the configuration of a fixing structure used to manufacture the prestressed girder of FIG.
15A and 15B show the configuration of a fixing structure used to fabricate the prestress girder of FIG.
Figures 16a to 16c is a view showing in sequence the process of replacing a part of the girder of the prestress girder made in accordance with the present invention
17 is an enlarged view of a portion 'C' of FIG. 16A.

Hereinafter, the prestress girder 100 according to the first embodiment of the present invention will be described in detail with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail to avoid obscuring the subject matter of the present invention.

As shown in the figure, the prestress girder 100 according to the first embodiment of the present invention is used to manufacture bicycles and sidewalk-only bridges supported by the cable 40, One segment girder 110 and a pair of second segment girder 120 which are arranged on both sides of the first segment girder 110 and connected to the first segment girder 110 in a longitudinal direction, respectively, each consisting of two segment girder 120. And a pair of third segment girder 130 arranged on both sides of the pair of second segment girder 120 to be longitudinally connected to the second segment girder 120, and the segment girder 110-130. It is composed of a tension member 50 for introducing a compression prestress while connecting one). Here, the segment girders (110-130) are supported by a support cable (40) connecting the piers or alternations.

Although not shown in the drawings, the fourth segment girder, the fifth segment girder ... may be arranged in a long length in both longitudinal directions of the pair of third segment girder 130.

Both sides of each segment girder (110-130) is provided with a web 112 is provided with a through hole as a receiving portion for receiving the tension member (50). The webs 112, 122, and 132 are made of a metallic material to have a sufficiently large strength or of a reinforced concrete material reinforced to a sufficient thickness. Segmented girders 110-130 are manufactured in the form of precast concrete blocks or plates made in advance in the factory. At this time, since the tension member 50 is fixed to both webs 112 of the segment girders 110-130, a large force acts. Accordingly, the webs 112, 122, and 132 on both sides of the segment girder 110-130 may be installed in a form in which a thick iron plate transverse to the segment girder 110-130 is embedded in the precast concrete. Thus, the webs 112, 122, 132 can be stably fixed to the segment girders 110-130, while the segment girders 110-130 are secured by the tension members 50 fixed to both webs 112, 122, 132. Compression prestress can be introduced uniformly across the shear surface of 130).

The first segment girder 110 is introduced into the first compression prestress (P1) by the tension member 50, the second segment girder 120 is introduced into the second compression prestress (P2) by the tension member (50) In the third segment girder 130, the third compression prestress P3 is introduced by the tension member 50. Although the second segment girder 120 and the third segment girder 130 may extend in an asymmetrical or one direction with respect to the first segment girder 110, the first segment girder 110 may be formed in the center 55. When the two segment girder 120, the third segment girder 130 and the like are symmetrically extended on both sides, the first segment girder 110 is located at the center of the prestress girder 100 to be manufactured. Therefore, since the largest tensile stress acts on the center portion of the span during use, the first compression prestress P1 introduced into the first segment girder 110 is the largest, and the smaller the compression is, the smaller the distance from the first segment girder 110 is. Act prestress.

Hereinafter, a method of manufacturing the prestress girder 100 according to the first embodiment of the present invention will be described in detail with reference to FIGS. 2A to 2E.

Step 1 : After installing the support cable 40 to the bridge to be built bridge, as shown in Figure 2a to mount a plurality of segment girders (110-130) to the support cable 40.

Step 2 : Then, the tension member 50 is installed so that the tension member 50 passes through the through holes of the webs 112, 122, and 132 protruding on both sides of the segment girder 110-130, as shown in FIG. 2B. do. At this time, in the position where the fixing unit 113 is to be installed, the fixing unit is inserted into the tension member 50 in advance.

Step 3 : Then, as shown in Fig. 2c, both ends of the tension member 50 are pulled by the tension force indicated by F1. Accordingly, the tension force of F1 acts on the entire tension member 50. Next, the tension member 50 is fixed to the web 112 located at both ends of the first segment girder 110 positioned at the center of the prestress girder 100 as the fixing unit 113 and the tension force F1 is removed. .

Thereby, the first compression prestress P1 is introduced into the first segment girder 110 according to the tension force indicated by F1, and the two first segment girder 110 is introduced into the tension member 50. By P1). Therefore, a process of introducing compression prestress to the first segment girder 110 and a process of bringing the two first segment girder 110 into close contact with each other are simultaneously performed by one operation.

At this time, since the first segment girder 110 is supported and mounted by the support cable 40, when the first segment girder 110 is fixed at both ends of the first segment girder 110, the first segment girder 110 is supported by the support cable 40. Sliding smoothly on the phase, it is easy to move to be in close contact with each other.

Step 4 : Then, as shown in Fig. 2D, both ends of the tension member 50 are pulled back to the tension force indicated by F2. Accordingly, the tension force of F2 acts on the tension member 50 in the longitudinal outer side of the second segment girder 120. At this time, since the second compression prestress P2 introduced into the second segment girder 120 is introduced to a smaller size than the first segment girder 110 positioned at the center of the girder, the tension force F2 of step 4 is increased. It is set smaller than the tension force F1 of three. Accordingly, the first compression prestress P1 is maintained in the first segment girder 110, and the tension force of F2 is applied to the second segment girder 120 and the third segment girder 130. do.

Next, the tension member 50 is moved from the web 122 of the second segment girder 120 located outside of the second segment girder 120 located on both longitudinal sides of the first segment girder 110 to the anchorage 123. Settle and remove tension (F2). The web 122 ′ of the second segment girder 120 positioned inside the second segment girder 120 serves as a guide through which the tension member 50 passes.

As a result, the first compression prestress P1 is maintained in the first segment girder 110, and the second compression prestress P2 is introduced into the second segment girder 120. At the same time, the first segment girder 110 and the second segment girder 120 are in close contact with each other in the longitudinal direction.

Meanwhile, in the exemplary embodiment of the present invention, the second compression prestress P2 is smaller than the first compression prestress P1, but the second compression prestress P2 is set larger than the first compression prestress P1. Can be. In this case, the fixing unit 113 fixed to both sides of the first segment girder 110 may be lifted to release the first compression prestress. Therefore, in this case, as shown in Figs. 14A to 14C, a fixing structure forcibly maintaining the fixing state should be applied even if a larger tension force is applied.

Step 5 : Then, as shown in Fig. 2E, both ends of the tension member 50 are pulled back to the tension force indicated by F3. Similarly, since the tension force F3 for introducing the third compression prestress P3 to the third segment girder 130 is set smaller than the tension force F2 for introducing the second compression prestress P2, the second segment girder ( The tension force of F3 acts on the tension member 50 of the longitudinal outer side of 120.

At this time, since the second compression prestress P2 introduced into the second segment girder 120 is introduced to a smaller size than the first segment girder 110 positioned at the center of the girder, the tension force F2 of step 4 is increased. It is set smaller than the tension force F1 of three. Accordingly, the first compression prestress P1 is maintained in the first segment girder 110, and the second compression prestress P2 is maintained in the second segment girder 120. The three segment girder 130 is in a state in which the tension force of F3 is applied.

Next, in the web 132 of the third segment girder 130 located on both sides of the second segment girder 120 in the longitudinal direction, the tension member 50 is fixed to the fixing unit 133 and the tension force F3 is removed. While introducing the third compression prestress P3 to the three segment girder 130, the third segment girder 130 is brought into close contact with both end surfaces of the second segment girder 120 in the longitudinal direction.

As the above method is expanded, the compression prestress is gradually increased as it reaches both ends from the first segment girder 110 located at the center 55 of the girder 100 while repeating the same for the fourth segment girder and the fifth segment girder. Less prestressed girders can be made. The prestress girder 100 manufactured as described above eliminates the conventional problem that excessive stress is introduced at both ends where the common load hardly acts, and introduces a compressive prestress that matches the load distribution acting in common, thereby unnecessary girder. It can solve the problem that the cross section of.

In addition, pedestrian bridges and bicycle bridges have no large live loads, so girder is generally formed in a small cross section and is formed as a long span bridge. Therefore, the process of forming the through-hole in the girder and inserting the tension material there is a very difficult problem, but as the tension material is formed on the outside of the cross section of the girder as described above, the installation of the tension material becomes very easy, and thus the workability is improved. You can get it. In the embodiment of the present invention, the configuration in which the receiving portion for receiving the tension member is located on both sides of the girder as an example, but the receiving portion of the tension member may be located in various positions such as the lower side, the upper side, both sides of the girder.

Hereinafter, using the prestress girder 100 produced as described above to produce a bicycle and sidewalk-only bridge is as follows.

After the pier 10 is erected as shown in FIG. 3A, the upper side of the pier 10 is connected to the support cable 40. In this case, the distance L between the piers 10 may be set equal to the length L of the prestress girder 100. Then, as shown in FIG. 3B, the precast concrete segment girder 110-130 manufactured at the factory and transported to the site by the transport vehicle 22 is lifted by the crane 20 to be supported by the support cable 40. Mount it.

Then, in accordance with the order shown in Figures 2a to 2e, after the tension member is installed on the webs 112, 122, 132 on both sides of the segment girder (110-130 ...), from the first segment girder 110 The prestresses P1, P2, and P3 are sequentially introduced to introduce compression prestresses P, which are scheduled in the entire girder 100, at intervals for each section (FIG. 3C). Then, the handrail 75 is installed, and the lower opening of the segment girder 110-130 is tightly sealed by the cover 42 so that the support cable 40 does not escape. This completes the construction of the bicycle and the only bridge 900.

As shown in FIG. 4, the bridge 900 constructed as described above is stably supported by self-loading and live loads by segment girder 110-130 into which compression prestress is introduced for each section, so that people, bicycles, and the like pass. Can be reliably supported. At this time, if necessary, the packaging surface 76 may be formed on the upper side of the segment girder 110-130 to smoothly construct the boundary surface of the segment girder.

Hereinafter, the process of replacing the segment girder positioned in the middle of the prestress girder 100 manufactured as described above will be described in detail with reference to FIGS. 16A to 17.

The prestress girders 100 are already fabricated in the state where the compression prestress is introduced by the tension member 50, but when the tension member is fixed by the fixing structure shown in Figs. 14A to 15B, the tension member is longitudinally fixed by the fixing structure. Since the relative position with respect to the segment girder 110-130 is fixed without moving, the state in which the compression prestress is introduced for each region of the segment girder bordering the fixing structure is maintained. Therefore, when some segment girder 120 'is damaged and only this is to be replaced, the area L2 to which this segment girder 120' belongs is not released, without releasing all of the compression prestress introduced into the prestress girder 100. FIG. Only release the compression prestress can be replaced with a new segment girder 120.

That is, when the damaged segment girder 120 'is generated in the prestress girder 100 as shown in FIG. 16A, the compression prestress is applied to the region L2 where the damaged segment girder 120' is located as shown in FIG. 16B. Loosen the fixing unit 122 for introducing the tension force introduced into the tension member (50). In the fixing structure 1 shown in Fig. 14A, it is performed by releasing the position fixing washer 1224. In the fixing structures 2 and 3 shown in Figs. 14B and 14C, the coupler 2222, 3221 is released. In the fixing structure 4 shown in Fig. 15A, the fixing tool 212 is released. In the fixing structure 5 shown in Fig. 15B, the fixing screw 5213 is released. .

As a result, the prestress P2 introduced in the region indicated by L2 is almost zero (Po). However, the compression prestresses P1 and P3 introduced at the time of fabrication of the prestress girder 100 are maintained in the adjacent regions L1 and L3.

Then, the damaged segment girder 120 'is lifted in the direction indicated by 120y and a new segment girder 120 is sandwiched between the segment girder in the direction indicated by 120y' as shown in FIG. 16C. At this time, in order to easily lift the segment girder 120 ', as shown in Fig. 17, it is preferable that the incision 122x cut downward is formed in the anchorage 122. However, the direction and shape of the cutout 122x may be variously selected.

Then, the compression prestress P2 is introduced into the region L2 in which the segment girder 120 is replaced by tightening the position fixing washer and the like of the fixing unit 122.

Such a process may be performed independently with respect to the prestress girder 100, but may be replaced even when the prestress girder is being used for the bridge. In particular, in the case of bicycles and sidewalk-only bridges shown in FIG. 4, there is an advantage that the damaged segmental girder (block) can be replaced even during the use of the bridge.

Meanwhile, as shown in FIG. 1, the tension members 50 are installed in the webs 112, 122, and 132 protruding from the segment girders 110-130, and the tension forces F1, F2, and F3 are repeatedly applied to the tension members 50. ), The anchoring state of the anchorage 113 is firmly maintained since the tension forces F2 and F3 introduced thereafter are smaller than the initial tension force F1. However, when the operator's mistake or intentionally introduces the tension force F2 introduced into the tension member 50 secondly is greater than the tension force F1 introduced first, the fixation state of the anchorage 113 settled primarily may be momentarily released. Can be. In order to prevent the release of the fixing unit 113, the fixing structures 1, 2, and 3 shown in FIGS. 14A to 14C may be applied.

The fixing structure 1 according to the first embodiment of the present invention can be applied when a cable such as a stranded wire is used as the tension member 50. That is, as shown in Fig. 14A, a male screw thread is formed on the outer circumferential surface of the fixing body 1222, and a pair of stop washers 1222 having a female screw thread engaged with the male screw thread are screwed to the fixing body 1222. Is located in a closed state. The pair of stop washers 1221 move on the fixing body 1222 to be in close contact with the plate surface of the web 122. As a result, the fixing body 1222 is fixed to the web 122.

The wedge member 1223 is a form generally used, and is divided into three at intervals of 120 degrees along the circumferential direction, and an inclined surface that is in contact with the inclined surface of the wedge receiving hole is formed on the outer circumferential surface. After placing the tension member made of the strand in the accommodation hole located in the center of the wedge member 1223, the wedge member 1223 is formed in the wedge accommodation hole formed in the center of the fixing body 1222 by tightening the position fixing washer 1224. It is fixed in position as it is seated. When the tension force F1 is removed, the first compression prestress P1 is introduced into the first segment girder 110 in the direction opposite to the tension force F1.

In this state, since the tension member 50 is fixed in position with respect to the web 122, even if a secondary tension force F2 larger than the primary tension force F1 is introduced in the left direction in Fig. 14A, the first segment girder 110 is introduced. The first compression prestress P1, which has been introduced into N, remains unaffected. Since a large force for maintaining the compression prestress acts on the web 122, the bending suppression reinforcement 128 may be coupled in a direction perpendicular to the web 122. The bending suppression reinforcement 128 may be formed only on both sides of the segment girder 110-130, but may extend across the transverse direction of the segment girder 110-130.

On the other hand, the fixing structure 2 according to the second embodiment of the present invention can be applied to the case of using a steel bar 500 having a thread formed on the outer circumferential surface as a tension member. That is, as shown in Figure 14b, a pair of stop washers (2221a, 2221b) with a female thread engaging with the male thread formed on the outer circumferential surface of the steel bar 500 is in close contact with the plate surface of the web 122 It is fixed. Then, a coupler 2222 fastened and moved along the male thread of the steel rod 500 is installed on the side where the tension force F1 acts, thereby bringing the coupler 2222 into close contact with the web 122, and the tension force F1 is applied. By removing, the first compression prestress P1 may be introduced into the first segment girder 110.

In this state, since the steel bar 500 is fixed in position with respect to the web 122, even if a force larger than the primary tension force F1 is introduced in the left direction in Fig. 14B, the first rod girder 110 has been introduced. One compression prestress P1 remains unaffected.

On the other hand, the fixing structure 3 according to the third embodiment of the present invention can be applied to the case of using a steel bar 500 having a thread formed on the outer circumferential surface as a tension member. That is, as shown in Figure 14c, a pair of steel rods 500 in a state in which a pair of steel bars 500 are respectively penetrated through a pair of webs 122 positioned at both ends of the first segment girder 110, respectively. The number formed on the outer circumferential surface of the steel bar 500 in a state in which the tension force F1 acting outwardly of the first segment girder 110 is applied after positioning the fixing nut 3223 located therebetween to be engaged at the same time. After coupling the coupler 3221 provided with the central portion to the outer surface of the web 122 with the female threaded portion engaged with the threaded portion, the first compressive prestress P1 is applied to the first segment girder 110 by removing the tension force F1. Can be introduced.

Hereinafter, the prestress girder 200 according to the second embodiment of the present invention will be described in detail. However, in describing the second embodiment of the present invention, a detailed description of functions or configurations overlapping with the above-described first embodiment will be omitted to clarify the gist of the second embodiment.

As shown in the figure, the prestress girder 200 according to the second embodiment of the present invention is arranged on both sides of the first segment girder 210 and the first segment girder 210, the first segment As long as the pair of second segment girder 220 connected to the girder 210 in the longitudinal direction and the second segment girder 220 are arranged on both sides of the pair of second segment girder 220 and connected to the second segment girder 220 in the longitudinal direction. A pair of fourth segment girder 230 and a pair of fourth segment girder 240 arranged on both sides of the pair of third segment girder 230 and connected longitudinally to the third segment girder 230 It is composed of tension members 40a and 40b for introducing compression prestress while connecting the segmental girders 210 to 240 as one. Here, the prestress girder 200 is manufactured by introducing the prestress while connecting the segment girder (210-240) on the ground.

Although the first segment girder 210 to the fourth segment girder 240 are each illustrated as one segment girder, the first segment girder 210 to the fourth segment girder 240 are each two or more segments. It may also consist of a girder. When manufacturing the prestress girder 200 while symmetrically extending from the first segment girder 210 in both longitudinal directions, the first segment girder 210 is positioned at the center of the prestress girder 200 finally produced. Therefore, when the span length of the bridge is sufficiently long, a plurality of segment girders may form the first segment girder 210 so that the maximum compression prestress determined by the design is introduced into the central region.

The segmental girders 210-240 are provided with a plurality of through holes penetrating through the segmental girders 210-240 as accommodation portions for accommodating the tension members 40a and 40b. These through holes are aligned such that longitudinally adjacent segment girders 210-240 communicate with each other. Tension members 40a and 40b are inserted into the through holes of the segment girder 210 to 240, and different compression prestresses are introduced to the segment girder 210 to 240 for each predetermined section.

Segmental girders 210-240 constituting the prestress girder 200 according to the second embodiment of the present invention may be formed of reinforced concrete mainly composed of concrete, as shown in FIG. 6A, and shown in FIG. 6B. As described above, the steel girder 230a 'and the casing concrete 230b' may be formed of a composite synthetic girder. Concave portions 212a and 222a are formed at both ends of each segment girder 210 to 240 so that the fixing holes 212, 222, and 232 are positioned. The recesses 212a and 222a may be filled with a filler such as non-shrink mortar after fixing.

Hereinafter, a manufacturing method of the prestress girder 200 according to the second embodiment of the present invention will be described in detail with reference to FIGS. 7A to 7C.

Step 1 : Arrange a plurality of segment girders (210-240) in the longitudinal direction to be the length of the girder 200 to be manufactured.

Step 2 : Then, install the tension member 50 to allow the tension members 40a and 40b to pass through the through holes of the longitudinally arranged segment girder 210-240. At this time, the fixing fixtures 212 and 222 may be previously fitted to the tension members 40a and 40b at the positions where the fixing fixtures 212 and 222 are to be installed. The tension member may be tension-fixed in various combinations so that the compression prestress may be introduced. In this embodiment, a method of introducing the compression prestress into two groups of the lower tension member 40a and the upper tension member 40b will be described as an example. .

In the drawing, reference numeral 210a is a lower through hole formed in the first segment girder 210, and 210b is an upper through hole formed in the first segment girder 210.

Step 3 : Then, after inserting the tension members 40a and 40b into the through holes of the segment girder 210-240, hold both ends of the lower tension member 40a with the tension force indicated by F1 as shown in FIG. 7A. Pull. Accordingly, the tension force of F1 acts on the entire lower tension member 40a. Next, the lower tension member 40a that is tensioned at both ends of the first segment girder 210 positioned at the center of the prestress girder 200 is fixed to the fixing unit 121 and the tension force F1 is removed. At this time, the fixing of the lower tension member 40a is performed in the space where the segment girders 210-230 are arranged in the longitudinal direction.

Thereby, the first compression prestress P1 is introduced into the first segment girder 210 according to the tension force indicated by F1. In addition, when two or more first segment girders 210 are formed, the two or more first segment girders 210 are brought into close contact with each other by a first compression prestress P1 introduced into the lower tension member 40a. At this time, the first segment girder 210 may be smoothly moved by the tension fixation of the tension member, and a roller or a plurality of small spheres may be distributed on the lower side of the segment girder 210-240 so as to easily slide or roll. .

Step 4 : Then, as shown in Fig. 7B, both ends of the upper tension member 40b and the lower tension member 40a are respectively pulled by the tension force indicated by F2. At this time, the secondary tension force F2 is set smaller than the primary tension force F1. Accordingly, the tension force of F2 acts only on the outer side of the first segment girder 220 in the lower tension member 40a, and the second tension of F2 in all sections including the first segment girder 220 in the upper tension member 40b. Tension is at work.

By fixing 222 and releasing the tension force F2 in the state in which the tension force is applied, the second compression prestress P2 is additionally introduced with the first compression prestress P1 introduced into the first segment girder 210. The compression prestress of P1 + P2 is introduced, and the second compression prestress P2 is introduced into the second segment girder 220 from the upper and lower tension members 40a and 40b to introduce the compression prestress of P2 + P2. At the same time, the first segment girder 210 and the second segment girder 220 are in close contact with each other in the longitudinal direction.

Step 5 : Then, as shown in Fig. 7C, only the upper tension member 40b is pulled back to the third tension force indicated by F3 only for the upper tension member 40b. Similarly, since the tension force F3 for introducing the third compression prestress P3 to the third segment girder 230 is set smaller than the tension force F2 for introducing the second compression prestress P2, the second segment girder ( The third tension force of F3 acts on the upper tension member 50 only in the outside in the longitudinal direction of 220).

By fixing 232 and releasing the tension force F3 while the tension force is applied, the compression prestress introduced to the first segment girder 210 and the second segment girder 220 does not change, but the third segment girder 230 In the third compression prestress (P3) is introduced, the second segment girder 220 and the third segment girder 230 is in close contact with each other in the longitudinal direction.

The prestress girder, which is gradually introduced with less compression prestress as both ends are extended from the first segment girder 210 positioned at the center of the girder, while repeating the same method for the fourth segment girder and the fifth segment girder. I can produce it. In this way, the compressive prestress is introduced into the segmental girders 210-240 by using the tension members 40a and 40b, but the tension material which has not been used for the introduction of the compression prestress before is used to introduce the next compression prestress. In addition, it is possible to repeatedly use the tension material used for the introduction of the compression prestress before it is used to introduce the next compression prestress, thereby adjusting the value of the compression prestress differentially introduced for each section in various distributions.

Meanwhile, as illustrated in FIG. 5, the tension members 40a and 40b are inserted into the through holes of the segment girders 210 to 240, and the tension forces F1, F2, and F3 are repeatedly introduced into the tension members 40a and 40b. In this case, since the tension forces F2 and F3 introduced thereafter are smaller than the initial tension force F1, the anchoring state of the fixing unit 212 is firmly maintained. However, the anchorage is settled primarily when the tension force (F2) applied after the operator's mistake or intentionally introduces the primary compression prestress (P1) to the tension members (40a, 40b) is greater than the tension force (F1) introduced first. The settling state of 212 can be released momentarily. In order to prevent the release of the fixing unit 212, the fixing members 4a and 5b shown in FIGS. 15a and 15b may be applied to the tension members 40a and 40b installed in the through holes of the concrete segment girder.

The fixing structure 4 of Fig. 15A according to the fourth embodiment of the present invention can be applied to the case of using a steel bar 400 having a thread formed on its outer circumferential surface as a tension member. In the drawings, the steel bar 400 is shown as being directly embedded in the concrete for convenience, the steel bar 400 is rotatably installed in the through hole or the sheath pipe.

That is, the fixing body 4212 formed at the center of the female thread portion engaged with the male thread portion of the steel rod 400 is embedded in the concrete of the segment girder, and accommodates the steel rod 400 in the fastened state at the female thread portion at the center portion thereof, In the state in which F1 is in operation, the coupler 212 engaging the male thread of the steel rod 400 abuts against the fixing plate 4212b of the fixing body 4212 supported by the end wall of the segment girder 210. By moving and removing the tension force F1 (or by rotating the coupler 212 to introduce the desired tension force F1 into the steel rod 400), it is possible to introduce the first compression prestress P1 into the first segment girder. do. The fixing body 4212 is buried together with a wing portion 4212a so that the concrete is firmly fixed to the first segment girder 210, which is the main material.

In this state, since the steel bar 400 is fixed in position with respect to the first segment girder 210, even if a force greater than the primary tension force F1 is introduced in the left direction of FIG. 15A, the steel segment 400 is applied to the first segment girder 210. The first compression prestress P1 that was introduced is not affected and remains intact.

The fixing structure 5 according to the fifth embodiment of the present invention can be applied when a cable such as a stranded wire is used as the tension member. That is, as shown in Fig. 15B, the fixing body 5212 is embedded in the concrete of the segment girder 210 in advance, and the wedge member 5211 which wraps the tension member 40a in the wedge receiving hole 5212h in the center thereof is formed. Are accepted. The fixing body 5212 has a wing portion 4212a embedded together so that the concrete is firmly fixed to the first segment girder 210 of which the concrete is a main material, and a fixing plate supported by the end wall of the first segment girder 210 ( 5212b).

The fixing body 5212 is provided with a protrusion protruding toward the direction in which the tension force F1 is introduced, and an external thread is formed on the outer circumferential surface of the protrusion, and the fixing nut is engaged in contact with one surface of the wedge member 5211 for the wedge. The position of the member 5211 is fixed. The wedge member 5211 is a form generally used, and is divided into three at 120 degree intervals along the circumferential direction, and the inclined surface which contacts the inclined surface of the wedge accommodating hole 5212h is formed in the outer peripheral surface. After placing the tension member made of the strand in the accommodation hole located in the center of the wedge member (5211), the wedge member (5211) is inserted into the wedge receiving hole (5212h) to remove the tension force (F1). As a result, the first compression prestress P1 is introduced into the first segment girder 210 in the direction opposite to the tension force F1. Then, the position of the wedge member 5211 is fixed with the position fixing washer 5213.

In this state, since the tension member 40a is fixed in position with respect to the first segment girder 210, even if a secondary tension force F2 larger than the primary tension force F1 is introduced in the left direction in Fig. 15B, the first segment The first compression prestress P1 introduced to the girder 210 remains unaffected.

Hereinafter, the prestress girder 300 according to the third embodiment of the present invention will be described in detail with reference to FIGS. 8 to 13D. However, in describing the third embodiment of the present invention, detailed descriptions of functions and configurations similar to those of the above-described first or second embodiments will be omitted for clarity. do.

As shown in the figure, the prestress girder 300 according to the third embodiment of the present invention is arranged on both sides of the first steel pipe segment girder 310 and the first steel pipe segment girder 310 A pair of second steel pipe segment girder 320 and a pair of second steel pipe segment girder 320 connected in a longitudinal direction with the first steel pipe segment girder 310 are arranged on both sides of the second steel pipe segment girder 320 And a pair of third steel pipe segment girder 330 connected in a longitudinal direction.

In the steel pipe segment girder according to the third embodiment of the present invention, webs 311 and 321 formed with through-holes through which the tension member 50 passes are formed therein, and the tension member 50 is tension-fixed in the web 311. Compression prestress is introduced into the pipe segment girder section by section. As shown in Fig. 11, a plurality of reinforcing members 311a, 321a .. are attached to the webs 311, 321,..., To maintain the tension-fixed state of the tension member 50.

In addition, a sleeve 80 shown in FIG. 10 is interposed between the connection portions of the steel pipe segment girder 310 to 330. The sleeve 80 includes a circumferential portion 81 surrounding both ends of the steel pipe segment girder 310, 320, and 330, and a side plate 82 formed at the center of the circumferential portion 81. As shown in FIG. 7A, the through plate 82 is formed to align with the through holes formed in the webs 211, 221, and 231 to accommodate the tension member 50.

The inner circumferential surface 81a of the circumferential portion 81 of the sleeve 80 is accommodated so as to surround the outer circumferential surfaces of both ends of the steel pipe segment girder 310, 320, 330, so that the steel pipe segment girder 310, 320, 330 is in a straight line shape. Assists in longitudinal alignment. When the fabrication of the prestress girder 300 is completed, the circumferential portion 81 of the sleeve 80 may be joined by welding 85 between the outer peripheral surfaces of the steel pipe segment girder 310, 320, and 330. .

Each of the steel pipe segment girder (310, 320, 330) is formed with a web (311, 321, 331) as a steel pipe diaphragm at both ends, respectively, the web 311, 321, 331 through a plurality of penetrations through which the tension member 50 passes A ball is formed.

Since the tension member 50 is settled in a tensioned state in the webs 211, 221, and 231, a support structure capable of supporting a large force is required. To this end, the inner reinforcement (311a, 321a, ....) forming a closed curved surface is coupled to the inner peripheral surface of each web (211, 221, 231), the inner reinforcement (311a, 321a, ...) and the steel pipe segment girder 310 Connection reinforcement for connecting the inner wall (..., 320i ....) of the, 320, 330, ..) is formed with a hole in between.

Although the steel pipe segment girder 310, 320, 330 is shown as one segment girder, the steel pipe segment girder 310, 320, 330 may be formed of two or more segment girder.

Hereinafter, the manufacturing method of the prestress girder 300 configured as described above will be described in detail.

Step 1 : As shown in Fig. 13A, the steel pipe segment girder 310-330 is longitudinally arranged with the sleeve 80 between the steel pipe segment girder 310-330.

Step 2 : Then, the tension member 50 is installed to penetrate the through holes of the webs 311, 321, and 331 and the through holes of the sleeve 80.

Step 3 : Then, as shown in FIG. 13B, the tension member 50 is tension-fixed in the web 321 of the second steel pipe segment girder 320 located on both sides of the first steel pipe segment girder 310. The first steel pipe segment girder 310 and the second steel pipe segment girder 320 are connected to each other while introducing the first compression prestress P1 into the first steel tube segment girder 310.

Step 4 : Then, as shown in FIG. 13C, the tension member 50 is tension-fixed in the web 331 of the third steel pipe segment girder 330 located on both sides of the second steel pipe segment girder 320. The second steel pipe segment girder 320 and the third steel pipe segment girder 330 are connected to each other while the second compression prestress P2 is introduced into the two steel tube segment girder 320.

Prestress girders (100, 200, 300) configured as described above can be produced quickly in the field using a segment girder made in advance in the factory, and the compression prestress is gradually introduced as it reaches both ends from the center step by step The advantageous effect of reducing the prestress introduction process and the connecting process into one process can be obtained.

Meanwhile, the prestress girders 100, 200, and 300 according to the present invention may be applied to a simple bridge, but may also be applied to a continuous bridge in which the girder continues in the longitudinal direction at the top of the bridge which is a continuous point portion. That is, the prestress girders are manufactured by connecting a plurality of segment girders by the above-described method so that the greatest compression prestress acts on the span center portion in which the great moment acts greatly, and the smaller compression prestress acts away from the span center portion. Afterwards, at the continuous point where the parent acts greatly, the longitudinally adjacent prestress girders are connected to the piers or alternating sections by introducing compressive prestresses at the upper edges of the neutral shafts by the tension members distributed at the upper edges of the neutral shafts of the composite section where the bottom plate is largely applied. It can also be used to build bridges through sequential girders.

Although two span bridges are illustrated in the drawings, it is apparent to those skilled in the art that the above configuration can be applied to two or more span continuous bridges.

In the above, the preferred embodiments of the present invention have been described by way of example, but the scope of the present invention is not limited to these specific embodiments, and may be appropriately changed within the scope described in the claims. That is, in the illustrated drawings, the compression prestress is introduced into the segmental girder in two or four stages to produce the prestressed girders 100, 200 and 300, but each of these segmented girders may be formed of two or more segmented girders. Therefore, it is possible to manufacture the prestressed girders connected in the longitudinal direction as the compression prestress is introduced in less than this step, and the interconnected prestress girders can be manufactured as the compression prestress is introduced in more steps than this. In addition, although the cross section of the steel pipe segment girder is illustrated as an example in the drawing, it may be configured as a steel pipe segment girder having a cross section of various shapes such as a square cross section.

100, 200, 300: prestressed girder 110, 210, 310: first segment girder
120, 220, 320: second segment girder 130, 230, 330: third segment girder
50: tension member 40a: lower tension member
40b: upper tension member 400, 500: steel bar
80: sleeve 81: circumference
82: side plate

Claims (23)

A segment girder arranging step of preparing a plurality of segment girders including a first segment girder and a second segment girder, in which a plurality of accommodation portions in which the tension member may be arranged in the longitudinal direction are formed, and the accommodation portion aligns in the longitudinal direction;
A tension member installation step of installing a tension member in the plurality of accommodation portions of the segment girder arranged in a longitudinal direction;
After tensioning the first tension member, which is a part of the tension member, anchorages are fixed to both ends of at least one of the first segment girder of the plurality of segment girders, so that the first compression prestress is applied only to the first segment girder by the first tension member. Introducing a first compression prestress;
After tensioning a part of the tension member, the second segment is fixed by fixing anchors at both ends of the first segment girder and at least one second segment girder longitudinally adjacent to the first segment girder among the plurality of segment girder. A second compression prestress introduction step of introducing a second compression prestress into the girder;
How to make prestressed girders to include.
The method of claim 1,
The tension member for introducing the second compressive prestress includes at least a portion of the first tension member.
The method of claim 2,
The tension force for introducing the second compression prestress is lower than the tension force for introducing the first compression prestress.
The method of claim 1,
The tension member for introducing the second compressed prestress is made of a second tension member that does not include the first tension member, and the second compression prestress is introduced into the first segment girder and the second segment girder. How to make Rest Girder
The method of claim 1,
And the second segment girder is arranged at both sides in the longitudinal direction of the first segment girder.
6. The method of claim 5,
After tensioning a part of the tension member, a fixing unit is fixed to both ends of at least one third segment girder adjacent to both sides of the second segment girder in the longitudinal direction of the plurality of segment girders, thereby compressing a third compression to the third segment girder. A third compression prestress introduction step of introducing prestress;
The production method of the prestressed girder which includes more.
The method of claim 1,
The receiving portion manufacturing method of the prestressed girder, characterized in that formed by the through-hole penetrating the segmental girder in the longitudinal direction.
The method of claim 1,
The receiving portion manufacturing method of the prestress girder, characterized in that formed on the outside of the segment girder.
9. The method according to any one of claims 1 to 8,
The segmental girder is a method of producing a prestressed girder, characterized in that it comprises a concrete girder as the main material.
9. The method according to any one of claims 1 to 8,
The segmental girder is a hollow portion provided inside, the method of manufacturing a prestressed girder, characterized in that the steel pipe girders formed with a web to which the fixing unit is fixed.
9. The method according to any one of claims 1 to 8,
The segmental girder is a method of manufacturing a prestressed girder, characterized in that the steel composite girders are a composite synthetic girder casing concrete.
9. The method according to any one of claims 1 to 8,
The first compression prestress introduction step and the second compression prestress introduction step is a manufacturing method of the prestress girder, characterized in that is carried out in a state mounted for the bridge.
9. The method according to any one of claims 1 to 8,
When the segment girder is closely contacted in the longitudinal direction by the length of the prestress girder to be manufactured, the step of cutting the end of the tension member exposed to both ends of the prestress girder further comprising the manufacturing of the prestress girder Way.
A fixing structure used to introduce compression prestress using a tension member passing through a receiving portion of a plurality of segment girders,
A web which protrudes perpendicularly to the longitudinal direction and has a through hole through which the tension member passes, at an end of the segment girder on which the anchorage is installed;
A fixing body arranged in the through hole and having a male thread formed on an outer circumferential surface thereof, and having a wedge receiving hole having an inclined inner surface at its center;
A pair of stop washers provided with female threads engaged with the outer circumferential surface of the fixing body to be in close contact with both sides of the web;
A wedge member having an inclined surface corresponding to the inclination of the wedge receiving hole on an outer surface thereof, and having a receiving hole for receiving a tension member formed by a strand in a center portion in a penetrating form, and being divided into two or more in the circumferential direction;
A position washer that engages with a male thread of the fixing body while pressing one surface of the wedge member;
Fixing structure comprising a.
A fixing structure used to introduce compression prestress using a tension member passing through a receiving portion of a plurality of segment girders,
A web which protrudes perpendicularly to the longitudinal direction and has a through hole through which the tension member passes, at an end of the segment girder in which the anchorage is installed;
A pair of stop washers provided with a female thread portion engaged with an outer circumferential surface of a tension member formed of a steel rod having a male thread portion formed on an outer circumferential surface thereof and in close contact with both sides of the web;
A coupler having a female thread portion engaged with an outer circumferential surface of the tension member to adjust the tension of the tension member at one side of the stop washer;
Fixing structure comprising a.
A fixing structure used to introduce compression prestress using a tension member passing through a receiving portion of a plurality of segment girders,
A web which protrudes perpendicularly to the longitudinal direction and has a through hole through which the tension member passes, at an end of the segment girder in which the anchorage is installed;
A coupler provided with a female thread engaging with an outer circumferential surface of a tension member formed of a pair of steel rods having a male thread portion formed on an outer circumference thereof, and being in close contact with the outer surfaces of the webs spaced apart from each other to rotate on the tension member so as to be in close contact with the web;
A fixing nut having a female threaded portion formed at a central portion thereof to receive the pair of steel bars between the pair of couplers;
Fixing structure comprising a.
A fixing structure used to introduce compression prestress using a tension member passing through a receiving portion of a plurality of segment girders,
The fixing plate is embedded in the end portion of the segment girder in which the fixing unit is installed and fixed in position, and a female screw portion is provided at the center portion so that the steel rod having a male thread portion is fastened as a tension member on the outer circumferential surface thereof, and the support plate is in contact with the end surface of the segment girder A fixing body provided;
A coupler having a female threaded portion engaged with a male threaded portion formed on the outer circumferential surface of the steel bar, the central portion being formed at the center portion thereof;
Including, the coupler is a fixing structure characterized in that the position is fixed in close contact with the fixing plate.
A fixing structure used to introduce compression prestress using a tension member passing through a receiving portion of a plurality of segment girders,
A fixing plate embedded in an end portion of the segment girder in which the fixing unit is installed and fixed in position, and provided with a fixing plate that is in contact with and supported by the end surface of the girder, and has a protrusion in which the male screw thread is formed by protruding outward in the longitudinal direction of the fixing plate; A fixing body having a wedge receiving hole formed therein;
A wedge member having an inclined surface corresponding to the inclination of the wedge accommodating hole on an outer surface thereof, having an accommodating portion for receiving the tension member in a center portion thereof, and being divided into two or more in the circumferential direction;
A fixing nut for engaging the male thread of the protrusion of the fixing body in contact with one surface of the wedge member to fix the position of the wedge member;
A fixing structure comprising a.
A prestress girder made by the method according to any one of claims 1 to 8.
A bridge manufactured by using a prestress girder manufactured by the method according to any one of claims 1 to 8.
The method of claim 20,
The prestress girders are manufactured so that the compression prestress is introduced while closely contacting the segment girders in the longitudinal direction on the ground and mounted on the piers, directly on the piers or alternations, or by the cables above the piers. A bridge characterized in that it is manufactured so that compression prestress is introduced while being in close contact with each other in a direction.
19. A method for manufacturing a prestress girder, comprising: fixing a tension member passing through a receiving portion of a plurality of segment girder by means of the fixing structure of any one of claims 14 to 18 and introducing stepwise compression prestress into the segment girder for each region;
A releasing step of releasing the compression prestress introduced only in the area containing the segment girder to be replaced;
A replacement step of replacing the segment girder to be replaced with a new segment girder;
Introducing compression prestress into a region that includes the replaced segmental girder;
How to replace the segmental girder of the prestressed girders included.
The method of claim 22,
The prestress girder is installed on the bridge, and the dismantling step and the replacement step are performed for the prestress girder installed in the bridge.

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