JP2023026012A - Support structure for temporary pier and renewal method of bridge upper structure - Google Patents

Abstract

To provide a support structure for a temporary pier which satisfies earthquake-resistant performance against a level 2 earthquake motion and can be installed at a low cost with a small amount of steel used without increasing the size, and to provide a method for renewing a bridge upper structure using the support structure.SOLUTION: In a support structure of a temporary pier 1 constructed between two existing piers P2, P3 erected separately and obtained by combining a plurality of steel materials, a plurality of cross beams 4 and a plurality of girder materials 5 installed on the plurality of cross beams 4 are provided, and the cross beams 4 are bridged and joined between a pair of frame bodies 3 respectively surrounding peripheries of the two existing piers P2, P3.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a temporary pier support structure and bridge superstructure renewal method, and more particularly to a temporary bridge pier support structure having seismic performance against level 2 seismic motion and a bridge superstructure renewal method using the same.

Superstructures (superstructures) such as bridge girders and floor slabs of bridges such as expressways need to be replaced and renewed after a certain period of time due to deterioration over time. When renewing superstructures of bridges such as expressways and railways, in order to renew them while they are still in service as expressways, etc., the renewal work is carried out one lane at a time, and a temporary structure, which is a temporary structure, is used instead of the lane that cannot be used during the renewal work. There is a request to build a bridge pier and install a floor slab on the temporary pier so that vehicles can pass through it. In this way, the temporary piers during temporary use are not only affected by seismic motions that frequently occur (hereafter referred to as level 1 seismic motions), but they are also extremely rare during the design period of the bridge, but once they occur, they can affect the bridge. In some cases, seismic performance against seismic motions that are considered to have a tremendous impact (hereafter referred to as level 2 seismic motions) is required (see Specifications for Highway Bridges (Seismic Design Version V) and its commentary).

Such temporary bridge piers are generally made of steel members because there is no curing period and on-site work can be done in a short period of time and because of the problem of versatility. However, since steel members cannot be expected to undergo plastic deformation, it is necessary to design them so that the level 2 seismic motion response value is within the elastic range. As a result, if there is seismic performance against level 2 seismic motion as a required performance of the temporary pier, there is a problem that the size of the temporary members will increase.

For example, in Patent Document 1, a temporary support is installed on the column head of a bridge pier proposed by the applicant of the present application, and fixed to the column head with a PC steel material. Disclosed is a method of overhang erection of a bridge in which concrete is placed in a mountain shape over the top of the pillars and concrete of a size that secures adhesion is placed around the top of the temporary diagonal members to form the formwork, and the temporary pillars used therefor are disclosed. (See claim 3 of the scope of claims of Patent Document 1, paragraphs [0020] to [0024] of the specification, FIGS. 1 to 4 of the drawings, etc.).

However, the temporary pillars described in Patent Document 1 are not supporting structures for temporary bridge piers, and they do not particularly consider seismic performance against level 2 seismic motion, so they could not solve the above problems.

JP-A-2006-52573

Therefore, the present invention has been devised in view of the above-mentioned problems, and the purpose thereof is to satisfy the seismic performance against level 2 seismic motion, to be able to install at low cost with less steel material usage without increasing size. To provide a support structure for a temporary bridge pier and a method for updating a bridge superstructure using the same.

A support structure for a temporary bridge pier according to claim 1 is a support structure for a temporary bridge pier constructed between two existing bridge piers that are spaced apart and constructed by combining a plurality of steel members, comprising a plurality of transverse beams, and a plurality of girders installed on the plurality of cross beams, wherein the cross beams are bridged and joined between a pair of frames surrounding the two existing bridge piers. and

A support structure for a temporary pier according to claim 2 is the support structure for a temporary pier according to claim 1, wherein the pair of frames are supported from below by a plurality of temporary pillars respectively erected along the existing piers. It is characterized by being

A support structure for a temporary bridge pier according to claim 3 is the support structure for a temporary bridge pier according to claim 1 or 2, wherein the horizontal beams are arranged in the pair of frames so that the response spectra of the two existing piers due to earthquake motion are synchronized. It is characterized by being rigidly joined with.

A support structure for a temporary pier according to claim 4 is the support structure for a temporary pier according to any one of claims 1 to 3, wherein a plurality of existing piers are erected with a space therebetween, and a frame surrounding each of the existing piers is provided. It is characterized in that the bodies are separated from each other and their frame bodies are connected by horizontal beams.

A bridge superstructure renewal method according to claim 5 is a bridge superstructure renewal method for replacing and renewing the superstructure of an existing bridge, wherein the temporary pier support structure according to any one of claims 1 to 4 is provided. After constructing the provided temporary bridge pier between two existing bridge piers which are erected apart from each other, a new superstructure to be replaced is placed on the temporary bridge pier.

A method for updating a bridge superstructure according to claim 6 is the method for updating a bridge superstructure according to claim 5, wherein the new superstructure includes precast PCa cross beams, and the PCa cross beams of the upper and lower lines are connected to each other. It is characterized in that it is connected via a steel shell and placed on the temporary pier, and a lane is temporarily provided between the two existing piers for common use.

According to the invention according to claims 1 to 4, since the horizontal beam is bridged and joined between the pair of frames surrounding the two existing piers, the horizontal force of level 2 seismic motion using the existing piers Because it can withstand level 2 seismic motion, it can have seismic performance. In addition, since the invention according to claims 1 to 4 uses the existing piers to counter the horizontal force of the seismic motion, compared to the case where the response value of the level 2 seismic motion is kept within the elastic range with the temporary piers alone. Even if it is composed of much smaller steel materials, it is possible to have the same earthquake resistance performance, and the temporary piers can be installed at low cost with less steel material usage.

In particular, according to the second aspect of the invention, there is no need to use post-installed anchors to fasten the frame to the existing piers, and the possibility of damaging the existing piers can be reduced. In addition, since the temporary posts are erected along the existing piers, there is no need for the temporary posts alone to withstand the horizontal force of seismic motion, and the size of the steel materials can be reduced and the installation can be done at low cost.

In particular, according to the third aspect of the invention, it is possible to have the same seismic performance even if the pier is made of a smaller steel material, and the temporary pier can be installed at a low cost with a small amount of steel material used.

In particular, according to the invention of claim 4, it is possible to increase the number of temporary piers in accordance with the progress of the renewal work, shorten the installation period of the temporary piers, thereby reducing the lease fee for temporary materials, It is possible to minimize obstacles such as traffic under the road.

According to the inventions of claims 5 and 6, the lateral beams of the temporary piers are bridged and joined between a pair of frames surrounding the two existing piers, respectively, so that the temporary piers can withstand level 2 seismic motion. It has seismic resistance performance against , and it is possible to safely update the superstructure.

In particular, according to the sixth aspect of the invention, the PCa cross beams to be newly installed are used to temporarily provide either one of the up and down lanes between the existing bridge piers for common use. Renewal work of the superstructure can be carried out.

FIG. 1 is a front view of a temporary pier having a temporary pier support structure according to a first embodiment of the present invention, viewed along the axis direction of an existing bridge. FIG. 2 is a plan view of FIG. 1 showing the same temporary bridge pier. FIG. 3 is a cross-sectional view of a vertical cross section of the same temporary bridge pier seen in a direction perpendicular to the bridge axis. FIG. 4 is a front view of a temporary pier having a temporary pier support structure according to a second embodiment of the present invention, viewed along the axis direction of the existing bridge. FIG. 5 is a perspective view of the bridge viewed in the direction of the bridge axis, showing the vertical line connecting horizontal beam erection process of the bridge superstructure renewal method according to the embodiment of the present invention. FIG. 6 is a perspective view looking down on the bridge, showing a step of constructing vertical line connecting horizontal beams in the method of updating the bridge superstructure as described above. FIG. 7 is a perspective view of the bridge viewed in the direction of the bridge axis, showing the outer cable release process of the method for updating the bridge superstructure. FIG. 8 is a partially enlarged perspective view showing an outer cable release step of the above bridge superstructure renewal method, showing an enlarged central two-lane portion of FIG. FIG. 9 is a perspective view of the bridge viewed in the direction of the bridge axis, showing the steel shell removal process of the bridge superstructure renewal method. FIG. 10 is a partially enlarged perspective view showing the steel shell removal step of the above bridge superstructure renewal method, showing an enlarged central two-lane portion of FIG. FIG. 11 is a perspective view of the bridge viewed in the direction of the bridge axis, showing the down-line horizontal beam tensioning process of the bridge superstructure renewal method described above. FIG. 12 is an enlarged perspective view showing an enlarged outer end portion of the PCa cross beam on the down line side, showing the down line cross beam tensioning process of the above bridge superstructure renewal method. FIG. 13 is a perspective view of the bridge as viewed in the direction of the bridge axis, showing the steel shell re-installation process of the above bridge superstructure renewal method. FIG. 14 is a partially enlarged perspective view showing the steel shell re-installation step of the above bridge superstructure renewal method, showing an enlarged central two-lane portion of FIG. 13 . FIG. 15 is a perspective view of the bridge viewed in the direction of the bridge axis, showing the outer cable re-tensioning process of the bridge superstructure renewal method described above. FIG. 16 is a partially enlarged perspective view showing the outer cable re-tensioning process of the above bridge superstructure renewal method, showing an enlarged central two-lane portion. FIG. 17 is a perspective view of the bridge viewed in the direction of the bridge axis, showing the outer cable release process of the above bridge superstructure renewal method. FIG. 18 is a partially enlarged perspective view showing an outer cable release step of the above bridge superstructure renewal method, showing an enlarged central two-lane portion. FIG. 19 is a perspective view of the bridge viewed in the direction of the bridge axis, showing the outer cable removal process of the bridge superstructure renewal method. FIG. 20 is a partially enlarged perspective view showing an outer cable removal step of the above bridge superstructure renewal method, showing an enlarged central two-lane portion. FIG. 21 is a perspective view of the bridge viewed in the direction of the bridge axis, showing the steel shell re-removal process of the bridge superstructure renewal method described above. FIG. 22 is a partially enlarged perspective view showing the steel shell re-removal process of the above bridge superstructure renewal method, showing an enlarged central two-lane portion of FIG. FIG. 23 is a perspective view of the bridge viewed in the direction of the bridge axis, showing the tension cable release process of the bridge superstructure renewal method described above. FIG. 24 is a partially enlarged perspective view showing the tension cable releasing process of the above bridge superstructure renewal method, showing an enlarged central two-lane portion of FIG. 23 . FIG. 25 is a perspective view of the bridge as viewed in the direction of the bridge axis, showing the tension cable removal process of the above bridge superstructure renewal method. FIG. 26 is a partially enlarged perspective view showing the tension cable removal step of the above bridge superstructure renewal method, showing an enlarged central two-lane portion of FIG. 25 . FIG. 27 is a perspective view of the bridge viewed in the direction of the bridge axis, showing the up-line horizontal beam tensioning process of the method for renewing the bridge superstructure. FIG. 28 is an enlarged perspective view showing an enlarged outer end portion of the PCa cross beam PB on the inbound line side, showing the inbound line cross beam tensioning process of the above bridge superstructure renewal method. FIG. 29 is a perspective view of the bridge viewed in the direction of the bridge axis, showing the completed state of the method for updating the bridge superstructure.

An embodiment of a method for updating a support structure for a temporary bridge pier and a bridge superstructure according to the present invention will be described below in detail with reference to the drawings.

<Support structure for temporary bridge piers>
[First embodiment]
A support structure for a temporary bridge pier according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 3. FIG. A temporary pier 1 constructed between two existing piers P2 and P3 by removing one upper and lower lane near the median strip when updating the superstructure B2 of the existing bridge B1 will be described. FIG. 1 is a front view of a temporary pier 1 having a support structure for a temporary pier according to a first embodiment of the present invention, viewed along the axial direction of the existing bridge. 2 is a plan view showing the temporary bridge pier 1 according to this embodiment, and FIG. 3 is a cross-sectional view of the vertical cross section of the temporary bridge pier 1 according to this embodiment as seen in the direction perpendicular to the bridge axis.

First, the existing bridge B1 will be briefly described. As shown in FIG. 1, the existing bridge B1 is a bridge of RC hollow slab girders with three lanes each for upper and lower lanes. This existing bridge B1 has, in a vertical cross section, a pair of left and right existing foundations F1 and F2, four existing bridge piers P1 to P4 erected on these foundations F1 and F2, and an upper part made up of an RC hollow floor slab girder. Structure B2 and so on. In addition, the upper structure B2 is provided with a wall balustrade K1, and a mounting-type temporary wall balustrade K2 that functions as a wall balustrade simply by being placed along the removed portion B2# of the superstructure B2 is installed. there is

As shown in FIGS. 1 to 3, the temporary bridge pier 1 according to the first embodiment is a temporary structure in which a plurality of steel materials are combined. This temporary bridge pier 1 comprises a plurality of temporary supports 2, a pair of right and left rectangular frame bodies 3 mounted on the plurality of temporary support supports 2, and a plurality of frame bodies 3 and 3 bridged between the frame bodies 3 and 3. and a plurality of girders 5 installed on the plurality of horizontal beams 4, and the like.

(temporary support)
The temporary support 2 according to the present embodiment is a support made of H-shaped steel, and the lower end is fixed to the foundations F1 and F2 with post-construction anchors, and the neck wrap concrete 2a is placed to the foundations F1 and F2. Fixed. A giraffe jack 2b is interposed between the temporary post 2 and the frame 3 so that the height of the frame 3 can be adjusted.

The temporary supports 2 have side surfaces attached along the existing bridge piers P2 and P3 and have the function of supporting the frame 3 from below. In this way, since the temporary supports 2 are attached along the existing piers P2 and P3, there is no need to use post-construction anchors to fasten the frame to the existing piers P2 and P3, which may damage the existing piers. can be reduced. In addition, since the temporary support 2 is erected along the existing bridge piers P2 and P3, it is not necessary for the temporary support 2 alone to resist the horizontal force of the seismic motion, and the size of the steel material can be reduced and installed at a low cost. can be done.

(frame body)
The frame body 3 according to the present embodiment is a rectangular frame body in which H-shaped steels are joined by welding or the like so as to surround the existing piers P2 and P3, respectively, and combined. It is configured such that the inner peripheral surface of the frame 3 abuts against the outer peripheral shape of the cross section. Of course, the frame 3 is not limited to H-shaped steel, and may be made of other steel such as channel steel or square steel pipe. Moreover, the frame 3 is not limited to being joined by welding, and may be joined mechanically, such as by bolting or riveting.

(horizontal beam)
The horizontal beam 4 according to the present embodiment is a steel material made of H-shaped steel, and is bridged and joined between the pair of frames 3, 3 described above. This cross beam 4 is rigidly joined to a pair of frames 3, 3 by welding or the like so that the response spectra of the two existing bridge piers P2, P3 due to seismic motion are synchronized. However, the horizontal beams 4 are not limited to being rigidly joined to the frames 3, 3, and may be joined by pins. This is because the existing bridge piers P2 and P3 can be used to resist the seismic motion simply by transmitting the axial force between the frames 3 and 3 with the horizontal beams 4 .

However, since the temporary pier 1 is rigidly connected to the frames 3, 3, it can cooperate with the existing piers against seismic motion, and even if the entire temporary pier 1 is made of small-sized steel materials, it can withstand level 2 seismic motion. It is possible to have performance, and it is possible to install temporary piers at low cost with less steel usage.

(Girder material)
The girder material 5 is a steel material made of H-shaped steel, placed on the horizontal beams 4, 4 and joined by welding or the like. The girder 5 according to this embodiment is placed on and joined to the lateral beams 4, 4 via spacer blocks 5a. Of course, the girder members 5 and the spacer blocks 5a are not limited to being joined to the cross beams 4 by welding, but may be joined mechanically such as by bolting or riveting. Further, the spacer block 5a may be made of H-shaped steel, like the girder 5.

According to the temporary pier 1 according to the first embodiment described above, the horizontal beam 4 is bridged between and joined to the pair of frames 3 surrounding the two existing piers P2, P3. Therefore, the existing piers P2 and P3 can be used to withstand the horizontal force of the level 2 seismic motion. Therefore, the temporary bridge pier 1 can have seismic performance against level 2 seismic motion.

In addition, since the temporary pier 1 uses the existing piers P2 and P3 to resist the horizontal force of seismic motion, it is much more effective than the case where the temporary pier 1 alone is designed to keep the level 2 seismic motion response value within the elastic range. It is possible to have the same seismic performance even if it is composed of a small steel material, and the temporary bridge pier 1 can be installed at a low cost with a small amount of steel material used.

[Second embodiment]
A support structure for a temporary bridge pier 1' according to a second embodiment of the present invention will be described with reference to FIG. A temporary pier 1' having a support structure for a temporary pier according to the second embodiment of the present invention differs from the temporary pier 1 according to the first embodiment described above in that the configuration of the temporary pier 1, which is essential, The difference is that other structures are added to the existing bridge piers P1 and P4 outside the existing bridge B1. Therefore, this point will be mainly described, and the same components will be denoted by the same reference numerals, and the description thereof will be omitted. FIG. 4 is a front view of a temporary pier 1' having a temporary pier support structure according to a second embodiment of the present invention, viewed along the axial direction of the existing bridge.

(bracket frame)
The temporary pier 1' has a bracket frame 6 so as to surround the existing piers P1 and P4 outside the existing piers P2 and P3. The bracket frame 6 is a rectangular frame formed by combining H-shaped steel so as to surround the existing bridge piers P1 and P4 by welding or the like. is projected outward in the direction perpendicular to the axis of the existing bridge B1 as a bracket portion 6a.

(bracket strut)
The inside of the bracket frame 6 is supported from below by the above-described temporary support 2, and the outside is supported by the bracket support 7 from below. Similar to the temporary support 2, the bracket support 7 is also made of steel such as H-shaped steel, and stands along the existing bridge piers P1 and P4. The lower ends of the bracket struts 7 are also fixed to the foundations F1 and F2 with post-installed anchors, and are fixed to the foundations F1 and F2 by placing neck-wrapping concrete 7a. The bracket strut 7 is rigidly joined to the bracket frame 6 by welding or the like without giraffe jacks.

The bracket post 7 has an elbow joint 7b projecting inward along the outer circumference of the existing bridge piers P1 and P4. The armrest 7b has the function of resisting the axial stress acting on the bracket portion 6a using the existing piers P1 and P4 by coming into contact with the outer circumferences of the existing piers P1 and P4. .

(diagonal material)
The bracket portion 6a of the bracket frame 6 is joined to and supported by the bracket strut 7 and the temporary strut 2 by a plurality of diagonal members 7c made of steel.

(Second cross beam)
A second cross beam 8 is bridged between the bracket frame 6 and the frame 3 . The second cross beam 8 is a steel material made of H-shaped steel, and is provided between the bracket frame 6 and the frame 3 so that the response spectra of the two existing bridge piers P1 and P2 (P3 and P4) due to earthquake motion are synchronized. It is rigidly joined by welding or the like. However, like the horizontal beam 4, the second horizontal beam 8 is not limited to being rigidly connected to the bracket frame 6 and the frame 3, and may be connected by pins.

On the second horizontal beam 8, the girder 5 described above is placed on the second horizontal beam 8 via spacer blocks 5a and joined by welding or the like.

(bracket girder material)
A plurality of bracket beam members 9 made of H-shaped steel are placed on the bracket portion 6a of the bracket frame 6 and joined by welding or the like.

According to the temporary bridge pier 1' according to the second embodiment described above, the second cross beam 8 surrounds the two existing bridge piers P1, P2 (P3, P4) between the bracket frame 6 and the frame 3. Since it is supported by the existing piers P1 and P2 (P3 and P4), the existing piers P2 and P3 are used to counter the horizontal force of the level 2 seismic motion. can do.

In addition, since the temporary pier 1' uses the existing piers P1 and P2 to resist the horizontal force of the seismic motion, compared to the case where the temporary pier 1' alone is designed to keep the level 2 seismic motion response value within the elastic range. It is possible to have the same seismic performance even if it is configured with a much smaller steel material, and the temporary pier 1' can be installed at a low cost with a small amount of steel material used.

In addition, according to the temporary pier 1', the frame 3 and the bracket frame 6 surrounding the existing piers P1 to P4 are separated from each other and connected by the cross beams 4 and the second cross beams 8. Temporary piers 1' can be added sequentially from the temporary pier 1 to the existing pier P4 side and the existing pier P1 side in accordance with the progress of construction. For this reason, according to the temporary pier 1', by shortening the installation period of the temporary pier 1', it is possible to reduce the leasing fee for the temporary material and to minimize obstacles such as traffic under the existing bridge B1. can. The temporary bridge pier according to the present invention can be suitably applied to a bridge having four or more existing piers by adding more bracket frames and cross beams.

<How to update the bridge superstructure>
Next, a method for updating a bridge superstructure according to an embodiment of the present invention will be described with reference to FIGS. 1, 4 and 5 to 29. FIG. Using the temporary pier 1' according to the second embodiment described above, the superstructure B2 consisting of the RC hollow floor slab girder of the existing bridge B1 having the four existing piers P1 to P4 and three lanes each of the upper and lower sides is precast. A case of updating by replacing with T digit T1 will be described as an example. In this embodiment, the plurality of T girders T1 are installed via precast PCa cross beams PB in order to reduce the number of bearings.

(Removal process of central part of upper structure)
First, as shown in FIGS. 1 and 4, in the bridge superstructure renewal method according to the present embodiment, the upper part B2#, which is an area of one upper and lower lane near the median strip of the superstructure B2, is removed. Carry out the process of removing the central part of the structure. At this time, as shown in FIG. 4, the above-described mounting type temporary wall balustrade K2 is installed along the removed portion B2# so as to prevent passing vehicles from falling.

(Temporary bridge pier installation process)
After that, as shown in FIG. 4, in the bridge superstructure renewal method according to the present embodiment, a temporary pier installation step of assembling and installing the aforementioned temporary pier 1' is performed.

However, at this time, as shown in FIG. 1, the above-described temporary pier 1 may be assembled and installed, and the remaining components of the temporary pier 1' may be sequentially added according to the progress of the renewal work. This is because, as described above, by shortening the installation period of the temporary bridge pier 1', it is possible to reduce the leasing fee for the temporary material and to minimize obstacles such as passage under the existing bridge B1.

(Upper and lower line connection horizontal beam erection process)
Next, as shown in FIGS. 5 and 6, in the method for updating the bridge superstructure according to the present embodiment, a vertical line connecting horizontal beam construction step is performed. FIG. 5 is a perspective view of the bridge as viewed in the direction of the bridge axis, showing the vertical line connecting horizontal beam erection process of the bridge superstructure renewal method according to the present embodiment, and FIG. 6 is a bridge showing the vertical line connecting horizontal beam construction process. 1 is a perspective view of a bird's-eye view of FIG.

In this process, PC brackets and fixtures are installed in advance, and the PCa cross beam PB of the up line and the PCa cross beam PB' of the down line are newly installed in the direction perpendicular to the bridge axis through the steel shell IB, which is a block body made of steel. The outer cable made of PC steel is tensioned and connected. Then, the PCa cross-beam PB and the PCa cross-beam PB' are placed on the girder 5 of the temporary pier 1'.

(T girder placement process)
Next, in the method for updating the bridge superstructure according to the present embodiment, a T-girder placing step of placing a plurality of T-girders T1 between the PCa lateral beams PB and PCa lateral beams PB' placed in the previous step is performed. Then, using PC brackets and tension cables, PC steel materials are tensioned between the PCa cross beams PB and PCa cross beams PB' in the bridge axis direction, and prestress is introduced to introduce a plurality of T girders T1 and PCa cross beams PB and PCa cross beams PB'. are integrated, and a new temporary road for two lanes is opened in the central part corresponding to the removed part B2# of the existing bridge B1, and it is shared as a temporary vehicle passage while performing renewal work.

At this time, the lateral beams 4 of the temporary pier 1' are bridged and joined between a pair of frames 3 surrounding the two existing piers P2 and P3, respectively, and are supported by the existing piers P2 and P3. Therefore, the new temporary route for two lanes in the center supported by the temporary bridge pier 1' can withstand the horizontal force of the seismic motion using the existing piers P2 and P3, and can also withstand level 2 seismic motion. be able to. For this reason, the new temporary track for two lanes in the central part supported by the temporary bridge pier 1 can have seismic performance against level 2 seismic motion, and can be used as a safe vehicle passage during superstructure renewal work. can.

(Down line superstructure removal process)
Next, in the method for updating the bridge superstructure according to the present embodiment, the new route for two lanes in the central part installed in the previous process is used as an outbound line, and the two lanes for the outer side shown in FIGS. The outbound line superstructure removal step is performed to remove the existing outbound line superstructure B2.

(Outbound line new construction process)
Next, in the method for updating the bridge superstructure according to the present embodiment, a new outbound PCa cross beam PB' is installed on the outbound two-lane portion removed in the previous process, and a plurality of T girders T1 are installed. A new outbound line installation process is performed.

(Outer cable release process)
Next, as shown in FIGS. 7 and 8, in the method for updating the bridge superstructure according to the present embodiment, the outer cables made of PC steel that have integrated the PCa lateral beams PB and PCa lateral beams PB' are released. Perform the release process. FIG. 7 is a perspective view of the bridge viewed in the direction of the bridge axis, showing the outer cable release process of the bridge superstructure renewal method according to the present embodiment. FIG. It is a partial expansion perspective view which shows a release process.

(Steel shell removal process)
Next, as shown in FIGS. 9 and 10, in the bridge superstructure renewal method according to the present embodiment, the steel shell IB interposed between the PCa lateral beam PB and the PCa lateral beam PB' is temporarily Carry out the steel shell removal process to be removed. FIG. 9 is a perspective view of the bridge viewed in the direction of the bridge axis, showing the steel shell removal process of the bridge superstructure renewal method according to the present embodiment, and FIG. It is a partially enlarged perspective view showing the same steel shell removing process.

(Outbound line horizontal beam tensioning process)
Next, as shown in FIGS. 11 and 12, in the bridge superstructure renewal method according to the present embodiment, PC steel materials are inserted into the space from which the steel shell IB was removed in the previous process, and fixed to both ends. A step of tensioning the PCa cross beams PB' on the side of the down line to integrate them is performed. FIG. 11 is a perspective view of the bridge viewed in the direction of the bridge axis, showing the down-line horizontal beam tensioning process of the bridge superstructure renewal method according to the present embodiment, and FIG. 12 is a down-line showing the down-line horizontal beam tensioning process. FIG. 11 is an enlarged perspective view of the outer end of the side PCa cross beam PB′;

(Steel shell re-installation process)
Next, as shown in FIGS. 13 and 14, in the bridge superstructure renewal method according to the present embodiment, a steel shell re-installation process is performed to re-install the steel shell IB removed in the previous steel shell removal process. FIG. 13 is a perspective view of the bridge viewed in the direction of the bridge axis, showing the steel shell re-installation step of the bridge superstructure renewal method according to the present embodiment, and FIG. 14 is an enlarged view of the central two-lane portion of FIG. Fig. 10 is a partially enlarged perspective view showing the steel shell re-installation process.

(Outer cable re-tensioning process)
Next, as shown in FIGS. 15 and 16, in the method for renewing the bridge superstructure according to the present embodiment, an outer cable re-tensioning step of re-tensioning the outer cables to integrate the PCa lateral beams PB and PCa lateral beams PB'. I do. FIG. 15 is a perspective view of the bridge viewed in the direction of the bridge axis, showing the outer cable re-tensioning process of the bridge superstructure renewal method according to this embodiment, and FIG. FIG. 4 is a partially enlarged perspective view showing a cable re-tensioning process;

(In-bound line superstructure removal process)
Next, in the bridge superstructure renewal method according to the present embodiment, after the preceding process is completed, the construction zone for the renewal work is changed from the outer two lanes of the outbound line to the outer two lanes of the inbound line, as shown in FIGS. An up-line superstructure removal process is performed to remove the existing superstructure B2 of the up-track for two outer lanes shown in .

(In-bound line new construction process)
Next, in the method for updating the bridge superstructure according to the present embodiment, a new PCa cross-beam PB for the in-bound line is installed on the in-bound line portion of the outer two lanes removed in the previous process, and then a plurality of T girders T1 are installed. An inbound line installation process for placing is performed.

(Outer cable release process)
Next, as shown in FIGS. 17 and 18, in the method for updating the bridge superstructure according to the present embodiment, an outer cable release step is performed to release the outer cable that integrates the PCa lateral beam PB and the PCa lateral beam PB'. . FIG. 17 is a perspective view of the bridge viewed in the direction of the bridge axis, showing the outer cable release process of the bridge superstructure renewal method according to the present embodiment, and FIG. It is a partial expansion perspective view which shows a release process.

(Outer cable removal process)
Next, as shown in FIGS. 19 and 20, in the bridge superstructure renewal method according to the present embodiment, an outer cable removal step is performed to remove the outer cables that have integrated the PCa lateral beams PB and PCa lateral beams PB'. . FIG. 19 is a perspective view of the bridge viewed in the direction of the bridge axis, showing the process of removing the outer cable in the bridge superstructure renewal method according to this embodiment, and FIG. It is a partial expansion perspective view which shows a removal process.

(Steel shell re-removal process)
Next, as shown in FIGS. 21 and 22, in the bridge superstructure renewal method according to the present embodiment, the steel shell IB interposed between the PCa lateral beam PB and the PCa lateral beam PB' is again removed. Carry out the steel shell re-removal process. FIG. 21 is a perspective view of the bridge viewed in the direction of the bridge axis, showing the steel shell re-removal process of the bridge superstructure renewal method according to the present embodiment, and FIG. Fig. 10 is a partially enlarged perspective view showing the steel shell re-removal process.

(Tension cable release process)
Next, as shown in FIGS. 23 and 24, in the bridge superstructure renewal method according to the present embodiment, the up-line side PCa lateral beams PB and the down-line side PCa lateral beams PB' near the central line are strained. Perform a tension cable release step to release the tension cable. FIG. 23 is a perspective view of the bridge viewed in the direction of the bridge axis, showing the tension cable release process of the bridge superstructure renewal method according to this embodiment, and FIG. FIG. 10 is a partially enlarged perspective view showing the same tension cable release process;

(Tension cable removal process)
Next, as shown in FIGS. 25 and 26, in the method for updating the bridge superstructure according to the present embodiment, the up-line side PCa lateral beams PB and the down-line side PCa lateral beams PB' near the central line are strained. A tension cable removal step is performed to remove the tension cable and PC bracket. FIG. 25 is a perspective view of the bridge viewed in the direction of the bridge axis, showing the tension cable removal process of the bridge superstructure renewal method according to this embodiment, and FIG. It is a partially enlarged perspective view showing the same tension cable removal process.

(Inbound line horizontal beam tensioning process)
Next, as shown in FIGS. 27 and 28, in the method for renewing the bridge superstructure according to the present embodiment, PC steel materials are inserted into the space from which the steel shell IB was removed in the steel shell re-removal process, and both ends are inserted. An up-line horizontal beam tensioning step is performed in which a fixture is installed in the part and the PCa horizontal beams PB on the up-line side are tensioned and integrated. FIG. 27 is a perspective view of the bridge viewed in the direction of the bridge axis, showing the up-line cross-beam tensioning process of the bridge superstructure renewal method according to the present embodiment, and FIG. FIG. 11 is an enlarged perspective view of the outer end of the side PCa cross beam PB;

Next, as shown in FIG. 29, in the method for updating the bridge superstructure according to this embodiment, by installing the wall balustrade K1 along the outer edge of the newly installed inbound line, the bridge upper structure according to this embodiment is installed. Renewal work of the structural renewal method is completed. FIG. 29 is a perspective view of the bridge viewed in the direction of the bridge axis, showing the completed state of the method for updating the bridge superstructure according to the present embodiment.

According to the method for updating the bridge superstructure according to the present embodiment described above, as described above, the lateral beam 4 of the temporary bridge pier 1' is positioned between the pair of frames 3 surrounding the two existing bridge piers P2 and P3. Since it is bridged and joined, the temporary pier 1' has seismic performance against level 2 seismic motion. For this reason, the two-lane temporary road in the center supported by the temporary pier 1' (temporary pier 1) can have seismic performance against level 2 seismic motion, and can be used as a safe vehicle passage during superstructure renewal work. can be used. Therefore, according to the bridge superstructure renewal method according to the present embodiment, superstructure renewal work can be performed safely and efficiently.

Further, according to the bridge superstructure updating method according to the present embodiment, either one of the up and down lanes is temporarily provided between the existing bridge piers P2 and P3 using the newly installed PCa cross beam PB (PB'). Since it is shared by both, it is possible to safely carry out the renewal work of the superstructure with fewer traffic restrictions.

In addition, the temporary bridge pier 1' used in the method for updating the bridge superstructure according to the present embodiment has the frame 3 and the bracket frame 6 that surround the existing bridge piers P1 to P4. 2 are connected by a cross beam 8. Therefore, the temporary pier 1' can be added sequentially from the temporary pier 1 to the existing pier P4 side and the existing pier P1 side in accordance with the progress of the renewal work. Therefore, according to the method for updating the bridge superstructure according to the present embodiment, by shortening the installation period of the temporary bridge pier 1', it is possible to reduce the leasing fee for the temporary materials and prevent obstacles such as traffic under the existing bridge B1. can be minimized.

As above, the support structure of the temporary pier and the method of updating the bridge superstructure according to the embodiment of the present invention have been described in detail. It is only a representation of the form. Therefore, the technical scope of the present invention should not be construed to be limited by these.

Further, as a method for updating a bridge superstructure according to the embodiment of the present invention, the case where the superstructure of the outbound line is first dismantled and renewed was exemplified. Needless to say, it's a good thing. In short, in the bridge superstructure renewal method according to the present invention, a temporary passageway is installed in the central part using temporary bridge piers for common use, and either one of the upper and lower lines is dismantled and removed first for renewal.

In particular, the case of replacing the upper structure B2 consisting of RC hollow slab girders of the existing bridge B1 with four existing bridge piers P1 to P4 and three lanes each on the upper and lower sides with a precast T girder T1 was explained as an example. , the number of piers and superstructure can be applied to any type of bridge regardless of existing or new construction. For example, it can be suitably applied when an existing RC hollow floor slab girder is replaced with a precast hollow hollow girder via a precast cross beam, like the SCBR construction method proposed by the applicant of the present application.

1, 1': Temporary pier 2: Temporary support 2a: Concrete wrapped around the neck 2b: Giraffe jack 3: Frame 4: Cross beam 5: Girder 5a: Spacer block 6: Bracket frame (frame)
6a: Bracket part 7: Bracket strut (temporary strut)
7a: Neck-wrapped concrete 7b: Bracket 7c: Diagonal member 8: Second horizontal beam (horizontal beam)
9: Bracket girder material B1: Existing bridge (bridge)
B2: Existing superstructure B2#: Removal part K1: Wall balustrade K2: Temporary wall balustrade P1-P4: Existing bridge piers F1, F2: Foundation PB, PB': PCa cross beam IB: Steel shell T1: T girder

The support structure of the temporary pier according to claim 1 is a renewal work of the superstructure of the existing pier by combining a plurality of steel materials constructed between two existing piers erected at a distance in the direction perpendicular to the bridge axis. A support structure for temporary piers that temporarily supports a newly constructed superstructure at the time of A frame, a plurality of transverse beams spanning between the pair of frames in a direction perpendicular to the bridge axis, and a plurality of transverse beams installed perpendicular to the transverse beams at the time of renewal. and a plurality of girders for mounting a superstructure , wherein the cross beams are bridged and joined between the pair of frames surrounding the two existing bridge piers.

A support structure for a temporary pier according to claim 2 is characterized in that, in the support structure for a temporary pier according to claim 1, the lateral beam is rigidly joined to the pair of frames.

A support structure for temporary piers according to claim 3 is the support structure for temporary piers according to claim 1 or 2 , wherein there are a plurality of existing piers erected with a space therebetween, and frames surrounding the existing piers are respectively It is characterized in that these frames are separate bodies and are connected by horizontal beams.

A bridge superstructure renewal method according to claim 4 is a bridge superstructure renewal method for replacing and renewing the superstructure of an existing bridge, wherein the temporary pier support structure according to any one of claims 1 to 3 is used. After constructing the provided temporary pier between two existing piers erected at a distance in the direction perpendicular to the axis of the bridge , a new superstructure to be replaced is placed on the temporary pier.

A method for updating a bridge superstructure according to claim 5 is the method for updating a bridge superstructure according to claim 4 , wherein the new superstructure is made of precast material corresponding to an up/down line installed along the direction perpendicular to the bridge axis. The upper and lower PCa horizontal beams are connected to each other in the direction perpendicular to the bridge axis with an outer cable made of PC steel through a steel shell, which is a block body made of steel . It is characterized in that it is placed on a girder , and a lane is temporarily provided between the two existing bridge piers in the direction perpendicular to the bridge axis for common use.

According to the invention according to claims 1 to 3 , since the horizontal beam is bridged and joined between the pair of frames surrounding the two existing piers, the horizontal force of the level 2 seismic motion is generated using the existing piers. Because it can withstand level 2 seismic motion, it can have seismic performance. In addition, the invention according to claims 1 to 3 uses the existing piers to resist the horizontal force of the earthquake motion, so compared to the case where the response value of the level 2 earthquake motion is kept within the elastic range by the temporary pier alone. Even if it is composed of much smaller steel materials, it is possible to have the same earthquake resistance performance, and the temporary piers can be installed at low cost using less steel material. In addition, according to the inventions of claims 1 to 3, it is not necessary to use post-installed anchors to fasten the frame to the existing piers, and the possibility of damaging the existing piers can be reduced. In addition, since the temporary columns are erected along the existing piers, there is no need for the temporary columns alone to withstand the horizontal force of the seismic motion, and the size of the steel material can be reduced and the installation cost can be reduced.

In particular, according to the invention of claim 2 , it is possible to have the same seismic performance even if it is made of a smaller steel material, and the temporary pier can be installed at a low cost with a small amount of steel material used.

In particular, according to the invention according to claim 3 , it is possible to increase the number of temporary piers according to the progress of the renewal work, and by shortening the installation period of the temporary piers, it is possible to reduce the leasing fee for temporary materials. It is possible to minimize obstacles such as traffic under the road.

Claims (6)

A support structure for a temporary bridge pier constructed between two existing piers set apart from each other and combining a plurality of steel materials,
comprising a plurality of transverse beams and a plurality of girders installed on the plurality of transverse beams,
A support structure for a temporary bridge pier, wherein the horizontal beam is bridged between and joined to a pair of frames surrounding the two existing bridge piers. The support structure for a temporary pier according to claim 1, wherein the pair of frames are supported from below by a plurality of temporary pillars erected along the existing pier. The support structure for a temporary bridge pier according to claim 1 or 2, wherein the transverse beams are rigidly joined to the pair of frames so that the response spectra of the two existing piers due to seismic motion are synchronized. There are a plurality of existing piers standing apart from each other, and frames surrounding each of the existing piers are separated from each other and are connected by cross beams. A support structure for a temporary bridge pier according to any one of the preceding claims. A bridge superstructure renewal method for replacing and renewing a superstructure of an existing bridge, comprising:
After constructing a temporary pier provided with the temporary pier support structure according to any one of claims 1 to 4 between two existing piers erected at a distance, the upper part of the new construction to be replaced on the temporary pier A method for renewing a bridge superstructure, comprising placing the structure. The new superstructure is equipped with precast PCa cross beams. The PCa cross beams of the upper and lower lines are connected to each other via steel shells and placed on the temporary piers. 6. The method for updating a bridge superstructure according to claim 5, wherein lanes are provided for common use.

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