JP6063795B2 - Bridge girder replacement method - Google Patents

Description

  The present invention relates to the replacement of a bridge girder used as an elevated road.

  In recent years, many elevated roads have deteriorated, and it is necessary to replace bridge girders on these roads. In particular, aging is progressing in urban areas, and there is a demand for technology for efficiently replacing bridge girders over a wide area. Therefore, for example, as shown in Patent Document 1, bridge girder replacement technology that minimizes traffic restrictions has been proposed. This technique uses a new side road. Further, although it relates to a road that is not elevated, as shown in Patent Document 2, a temporary road for securing traffic equivalent to two lanes has also been proposed.

JP 2007-32473 A JP 2006-233464 A

  By the way, in urban areas, elevated roads are constructed between buildings, and it is difficult to provide a work space on the side of the road when replacing bridge girders. It is also difficult to secure land for the bypass road to prevent traffic blockage. As a result, road closures are required. However, closures in urban areas result in significant economic losses.

  This invention is made | formed in view of the said subject, and it aims at replacing a bridge girder, without performing a traffic stop.

  The invention according to claim 1 is a method of replacing a bridge girder having four or more lanes, and a) in a traffic regulation section including a bridge girder to be relocated, more centrally than two outermost lanes. Stopping the traffic in the inner lane group in which two or more lanes are lined up and maintaining the traffic in the outer lane group, which is a lane other than the inner lane group, and b) traversing the bridge girder vertically above the inner lane group And a step of installing a temporary bridge including two or more lanes; c) starting traffic of the temporary bridge and stopping traffic of the outer lane group; and d) above the outer lane group. E) a step of installing a temporary support structure that exists over the entire length of the bridge girder; e) a step of dismantling and removing the bridge girder while using the temporary support structure, and installing a new bridge girder; Removing the temporary support structure from the outer lane group; and g) the outer lane. Traffic was started and a step of stopping the provisional bridge traffic, a step of removing the said temporary bridge from the h) the inner lane group, i) a step of starting the transportation of said inner lane group.

  The invention according to claim 2 is the bridge girder replacement method according to claim 1, wherein the bridge girder to be replaced is changed to a bridge girder adjacent to the new bridge girder before the step i). The steps a) to h) are further repeated, and in the step d) in the repetition step, the temporary support structure moves from the new bridge girder onto the bridge girder to be newly replaced. .

  The invention according to claim 3 is the bridge girder replacement method according to claim 1, wherein the bridge girder to be replaced is changed to a bridge girder adjacent to the new bridge girder before the step i). The steps a) to h) are further repeated, and in the step b) in the repeating step, the temporary bridge moves from the new bridge girder to the bridge girder to be newly replaced.

  Invention of Claim 4 is the bridge girder replacement | exchange method in any one of Claim 1 thru | or 3, Comprising: The said bridge girder used as replacement object exists over several diameters, The said e ) In the process, partial bridge girder replacement between one or a plurality of non-adjacent spans is repeated.

  The invention according to claim 5 is the bridge girder replacement method according to any one of claims 1 to 4, wherein the step e) is a cross beam positioned below the inner lane group across the span. Removing at least a part of the bridge girder along the longitudinal direction of the bridge girder, moving the main girder and the cross girder located below the outer lane group inward between the spans, and the span And supporting the girder support beam below the main girder by the temporary support structure, and supporting the main girder from below with the girder support beam between the spans and the remaining main girder and side Dismantling the girder.

  According to the present invention, bridge girders can be replaced while maintaining traffic of two or more lanes.

It is a figure which shows the flow of bridge replacement. It is a figure which shows the flow of bridge replacement. It is a figure which shows the flow of bridge replacement. It is a figure which shows the flow of the dismantling of a girder. It is a figure which shows the flow of installation of a girder. It is sectional drawing of the bridge girder after step S11. It is a side view of the bridge girder after step S11. It is sectional drawing of the bridge girder after step S13. It is sectional drawing of the bridge girder after step S14. It is a side view of the bridge girder after step S14. It is sectional drawing of the bridge girder in step S16. It is a side view of the bridge girder in step S16. It is sectional drawing of the bridge girder in step S17. It is a side view of the bridge girder in Step S17. It is sectional drawing of the bridge girder in step S101. It is sectional drawing of the bridge girder in step S103. It is a side view of the bridge girder in step S103. It is sectional drawing of the bridge girder in step S104. It is a side view of the bridge girder in step S104. It is a perspective view of the bridge girder after Step S104. It is a perspective view of a bridge girder in Step S105. It is a perspective view of a bridge girder in Step S105. It is sectional drawing of the bridge girder after step S105. It is a side view of the bridge girder after Step S105. It is a side view of the bridge girder after Step S105. It is sectional drawing of the bridge girder in step S111. It is sectional drawing of the bridge girder in step S112. It is a side view of the bridge girder in step S112. It is sectional drawing of the bridge girder in step S113. It is a side view of the bridge girder in step S20. It is a side view of the bridge girder in step S20. It is a side view of the bridge girder after step S32. It is a side view of the bridge girder after step S32. It is a side view of the bridge girder after Step S34. It is sectional drawing of the bridge girder after step S35. It is a side view of the bridge girder in step S36. It is a side view of the bridge girder in step S36. It is sectional drawing of the bridge girder after step S38. It is sectional drawing of the bridge girder in step S40. It is a side view of the bridge girder in step S40. It is sectional drawing of the bridge girder after step S41. It is sectional drawing of the bridge girder at the time of moving a temporary bridge. It is sectional drawing of the bridge girder at the time of moving a temporary bridge. It is sectional drawing of the bridge girder at the time of median zone driving. It is a figure which shows a traffic flow line. It is a figure which shows the traffic flow line after step S12. It is a figure which shows the traffic flow line in step S16. It is a figure which shows the traffic flow line in step S16. It is a figure which shows the traffic flow line after step S16. It is a figure which shows the traffic flow line after step S40. It is a figure which shows the traffic flow line at the time of moving a temporary bridge. It is a figure which shows the traffic flow line at the time of moving a temporary bridge.

  The present invention is mainly used to replace bridge girders on an aging elevated road. In the embodiment described below, the bridge is a three-span continuous girder bridge. That is, a bridge girder including one continuous girder is positioned on four piers. The 3-span continuous girder bridge is the most common structure of so-called urban highways, which are elevated roads in urban areas. The number of lanes on the road is 4 lanes. The length of the bridge girder and the number of lanes to be replaced are not limited to those exemplified in the present embodiment.

  In addition, below the bridge girder may be used as a general road. General roads can be restricted for a short time, but cannot be restricted for a long time. Replacement of the bridge girder according to the present embodiment is possible even under conditions where materials and structures cannot be installed for a long time under the bridge girder. Further, even during the assembly and dismantling of temporary facilities on the bridge girder, and during the dismantling and erection of the bridge girder, two lanes of the expressway, that is, traffic lines of one lane each for the up and down lanes are always secured.

  FIG. A through FIG. C is a figure which shows the whole flow of the bridge girder replacement | exchange process. FIG. A and FIG. B is a diagram showing a part of the process.

  FIG. A is a cross-sectional view perpendicular to the lane of the bridge girder 11 to be replaced, and FIG. B is a side view parallel to the lane. The bridge girder 11 is shown in FIG. As shown to B, it is constructed on the four bridge piers 12 via the eaves 121. In the replacement of the bridge girder 11, first, the edge widening device 31 is attached to the pier 12 as a preparation work (step S11). The edge widening device 31 enlarges the width of the pier 12 in the lane direction. Further, the reinforcing rib 32 is attached to the bridge girder 11 by welding or a high-strength bolt just above the edge widening device 31. The reinforcing rib 32 is a reinforcing member for the bridge girder when the bridge girder 11 is supported on the edge widening device 31 in a later step. If the width of the pier 12 in the lane direction is sufficiently wide and the strength of the bridge girder 11 is sufficient, these preparatory operations are unnecessary.

  Next, in the traffic regulation section including the bridge girder 11 to be replaced, as shown in FIG. 4, guardrails 33 are installed between the two lanes on the center side and the lanes on both ends. The traffic in the two lanes on the central divider side (hereinafter referred to as “inner lane group 13”) is stopped, and one-lane one-lane traffic is set (step S12). Hereinafter, the closed area is referred to as “permanent regulation zone”. Traffic is maintained in the two lanes outside the inner lane group 13 (hereinafter referred to as “outer lane group 14”). That is, traffic in two directions opposite to each other is maintained. Hereinafter, a lane in which traffic is maintained is referred to as a “passage zone”. The median strip 111 (see FIG. 3.A) is removed (step S13).

  A crane is carried into the permanent regulation zone. A and FIG. As shown in B, the temporary bridge 41 is installed above the inner lane group 13 (step S14). The temporary bridge 41 includes two lanes, and traverses the bridge girder 11 to be replaced. The temporary bridge 41 includes a main body part 411 extending in parallel with the bridge girder 11 above the bridge girder 11 and approach parts 412 positioned on both sides in the longitudinal direction of the main body part 411. The approach part 412 is located on the bridge girder 11 a adjacent to the bridge girder 11, and is inclined from the traveling surface of the bridge girder 11 a toward the main body part 411 and connected to the main body part 411.

  When the temporary bridge 41 is assembled, the traffic of the temporary bridge 41 is started, the temporary bridge 41 becomes a traffic zone, the traffic of the outer lane group 14 is stopped, and the outer lane group 14 becomes a permanent restriction zone (step S15). And FIG. A and FIG. As shown to B, the movement temporary support structure 42 is installed in the outer side lane group 14 (step S16). The moving temporary support structure 42 exists over the entire length of the bridge girder 11. FIG. B is a side view showing only the outer lane group 14, and the side surface of the inner lane group 13 is shown in FIG. As shown in B. As will be described later, after the moving temporary support structure 42 is assembled at a position away from the temporary bridge 41, FIG. As shown to B, it moves along the rail of the delivery equipment 37, and is installed in the side of the temporary bridge 41. As shown in FIG. After installation, the delivery facility 37 is removed.

  The moving temporary support structure 42 is provided with a crane 422 that moves along the lane. In addition, FIG. A and FIG. As shown in B, a crane 413 that moves vertically and horizontally in the lane is provided below the temporary bridge 41. Using the cranes 413 and 422, FIG. A and FIG. As shown in B, pavement, floor slab concrete, etc. on both sides of the three spans (hereinafter referred to as “side span 132” and the central span is referred to as “center span 131”). It is removed (step S17). Thereby, the upper part of the part of the side span 132 of the cross beam (hereinafter, each span portion of the cross beam is referred to as “cross span 2”) is exposed. At this time, the removable portion of the pavement or floor slab of the center span 131 may be removed.

  Next, disassembly and removal of the span girder 2 at the side span 132 are performed using the cranes 413 and 422 (step S18). The removal of the span girder 2 is performed from the innermost cross beam 22 as shown in FIG. 8 (FIG. 2.A: step S101). FIG. As shown in FIG. 8A, in the present embodiment, the span girder 2 is divided into six sections 20 in the horizontal direction by the main girder 21, and the cross beams 22 of the two inner sections 20 as shown in FIG. Will be removed. That is, in the side span 132, the innermost cross beam 22 is removed along the longitudinal direction of the bridge beam 11. Furthermore, FIG. As shown in FIG. B, a temporary tack 35 is installed on the edge widening device 31 as necessary, and the original tack 121 (see FIG. 3.B) is removed, and FIG. A and FIG. As shown in B, the pre-installation equipment 36 is installed on the pier 12 (step S102).

  A portion of the side span 132 of the main girder 21 is cut from a portion of the central span 131 at a position on the pier 12. Further, the remaining portions of the main beam 21 and the cross beam 22 in the side span 132, that is, the remaining four sections 20 are moved inward by the pre-installation equipment 36 (step S103). As a result, FIG. As shown in A, a space is created below the moving temporary support structure 42. Using this space, FIG. A and FIG. As shown in B, the girder support beam 423 is lifted from below by the crane 422. Thereafter, the girder support beam 423 is suspended and supported from the moving temporary support structure 42 in a state of supporting the main girder 21 from below (step S104).

  In the side span 132, the girder support beams 423 are arranged so as to support both sides of the connecting portion of the main girder 21. FIG. 11 is a perspective view showing a state in which the girder support beams 423 are arranged. In this state, the remaining portions of the main beam 21 and the cross beam 22, that is, the parts between the side spans 132 of the four sections 20 are disassembled and removed (step S105). First, as shown in FIG. 12, by removing the bolt, the cross beam 22 of the outer section 20 is removed, and then a part of the outer main beam 21 is removed while being supported by the beam support beam 423. By repeating this operation, the outer section 20 is removed. Thereafter, as shown in FIG. 13, the remaining portions are moved outward. And the main girder 21 and the cross beam 22 which comprise the remaining division 20 in the side span 132 are removed by repeating the same dismantling operation | work. Note that FIG. A and the main main girder 21 shown in FIG. 11 are finally removed.

  With the above operation, FIG. A to FIG. As shown in C, there is no girder in the side span 132, and the girder support beam 423 is suspended. FIG. B is a side view at the position of the moving temporary support structure 42, and FIG. C is a side view at the position of the temporary bridge 41.

  Next, a new span girder 2 is assembled in the side span 132 using the girder support beam 423 by a reverse operation to the dismantling operation (FIG. 1.A: step S19). Specifically, as shown in FIG. 15, a part of a new main girder 21 is carried in and one main girder 21 is assembled using a girder support beam 423. The main girder 21 is moved inward by the pre-installation facility 36. Further, the first section 20 is assembled using the beam support beams 423. The section 20 is moved inward using the pre-installation equipment 36, and the adjacent section 20 is further assembled (FIG. 2.B: step S111).

  At this stage, FIG. A and FIG. As shown in B, the girder support beam 423 descends (step S112), and the girder support beam 423 is removed. As shown in FIG. 17, the two pairs of sections 20 are moved to the outermost side by the pre-installation facility 36 (step S113). Thereafter, the horizontal installation facility 36 is removed from the pier 12 (step S114), and the horizontal beam 22 is attached between the central main beam 21 and the section 20 (step S115). Thereby, the assembly of the span girder 2 in the side span 132 is completed. In this way, the work of disassembling and removing the span portion of the bridge girder 11 and installing the span portion of the new bridge girder is performed using the moving temporary support structure 42. The same applies to the work in the center span 131 described later.

  FIG. A and FIG. As shown to B, the leg part 424 of the movement temporary support structure 42 and the leg part 414 of the temporary bridge 41 are moved from the side span 132 to the center span 131 (FIG. 1.A: Step S20). Precisely, after the new leg portions 424 and 414 are assembled in the side span 132, the original leg portions 424 and 414 on the central span 131 are removed.

  Next, as in the case of the side span 132, the girders of the central span 131 are removed and newly installed. That is, a pavement, a floor slab, etc. are removed in the center span 131 (FIG. 1.B: step S31), FIG. A process similar to that in FIG. A and FIG. As shown in B, using the girder support beam 423, the span girder 2 at the center span 131 is disassembled and removed (step S32). Furthermore, FIG. A new span girder 2 is assembled in the central span 131 through the same process as B (step S33). The span girder 2 of the side span 132 and the span trough 2 of the central span 131 are connected (step S34). To be exact, for the sake of work, the span girder 2 of the side span 132 is slightly shorter than the original one, and the span trough 2 of the central span 131 is slightly longer. Therefore, the connection position is slightly biased toward the side span 132 side from the center of the pier 12.

  As a result of the above operation, as shown in FIG. 20, a single stringer 200 spanning three diameters is completed. In addition, instead of the temporary fence 35 on the edge widening device 31, a fence 121 is installed on the pier 12.

  Forms are assembled on the spatula 200, and the area for the floor slab 23 is placed on the spatula 200 as shown in FIG. Concrete is placed (step S35). Then, FIG. A and FIG. As shown to B, the leg parts 424 and 414 are moved on the newly provided floor slab 23 (step S36). Precisely, after the new legs 424, 414 are assembled, the original legs 424, 414 are removed. Concrete is cast at the position where the leg portions 424 and 414 exist (step S37), and the floor slab 23 is completed over the entire length between the three diameters. Further, as shown in FIG. 23, the wall height column 24 is also made of concrete (step S38). The edge widening device 31 is removed as appropriate.

  When there is a next new construction zone, that is, a bridge girder 11 to be replaced next (step S39), the same work in the new construction zone is performed with the bridge girder 11 adjacent to the bridge girder 11 just after the replacement as the replacement target. Transition.

  First, FIG. A and FIG. As shown in B, a delivery facility 37 is laid under the moving temporary support structure 42. The moving temporary support structure 42 is removed from the outer lane group 14 along the rails of the delivery facility 37 so as to retreat to the opposite side to the new work area (step S40). The area after evacuation is paved. As shown in FIG. 25, the traffic of the outer lane group 14 is started, and the outer lane group 14 becomes a traffic zone. On the other hand, the traffic of the temporary bridge 41 is stopped, and the temporary bridge 41 becomes a permanent regulation zone (step S41).

  Thereafter, the bridge girder 11 in the new construction area is replaced according to the operations of steps S11 to S20 and S31 to S38 described above. However, since the temporary bridge 41 and the moving temporary support structure 42 are already assembled, these installations are realized only by movement. Specifically, in the installation of the temporary bridge 41 in step S14, first, the floor slab and the like of the temporary bridge 41 located in the old construction area are removed, and the width of the temporary bridge 41 is as shown in FIG. Narrowed as shown in A. Furthermore, FIG. A and FIG. As shown in B, a delivery facility 38 is laid under the temporary bridge 41. In this state, the temporary bridge 41 moves on the rail of the delivery facility 38 to the new work area. When arriving at the new construction zone, the delivery facility 38 is removed, the width of the temporary bridge 41 is widened, and the running surface is adjusted. With the above operation, the temporary bridge 41 is removed from the inner lane group 13 of the old work area and the temporary bridge 41 is installed in the inner lane group 13 of the new work area.

  As shown in FIG. 27, the concrete of the median strip 111 is placed and paved in the area where the temporary bridge 41 on the old work area exists. In step S15 of the work in the new work zone, when the temporary bridge 41 is set as a traffic zone and the outer lane group 14 is set as a permanent regulation zone, the traffic of the inner lane group 13 in the old work zone is started. At this time, the traffic of the outer lane group 14 in the old work area is stopped. In addition, when the work zone goes further to a certain extent, traffic in all lanes of the old work zone will be restored.

  In the installation of the temporary moving support structure 42 in step S16 in the new work area, the moved temporary support structure 42 that has been evacuated is moved to the new work area by the sending equipment 37, and the sending equipment 37 is removed.

  While moving the temporary bridge 41 and the moving temporary support structure 42, the bridge girder 11 is repeatedly replaced for each work section, and when the work in all the work sections is completed (step S39), the moving temporary support structure 42 is retracted and disassembled. Removal is performed (FIG. 1.C: step S51). The outer lane group 14 is paved. Then, the outer lane group 14 is set as a traffic zone, and the temporary bridge 41 is changed to a permanent regulation zone (step S52). The temporary bridge 41 is disassembled and removed (step S53), the concrete of the median strip 111 is placed, and the inner lane group 13 is paved. Thereafter, the traffic regulation is canceled (step S54), and the replacement of all bridge girders 11 is completed.

  Next, how traffic lines are switched in the above construction method will be described with reference to FIGS.

  FIG. 28 is a diagram showing the traffic flow lines of automobiles in four lanes with arrows. A range 81 between the three diameters is a range of the bridge girder 11 to be replaced. FIG. 29 shows a state where the inner lane group 13 is set as a permanent regulation band in step S12. A range 821 is a regulation band, and a range 822 is a diversion zone. The whole of the regulation zone 821 and the diversion zone 822 corresponds to the traffic regulation section. The regulation band 821 is used as a range for assembling the temporary bridge 41. Therefore, the regulation band 821 is set sufficiently longer than the temporary bridge 41. The temporary bridge 41 is installed in a range extending by one diameter from the range 81 to the left and right. Of course, a longer approach 412 may be provided.

  FIG. 30 is a diagram showing traffic flow lines when the moving temporary support structure 42 is assembled. A restriction band 821 is set on the further right side of the diversion band 822 on the right side of the temporary bridge 41. Then, as shown with parallel oblique lines, an assembly region having a width of two lanes is set, and the moving temporary support structure 42 is assembled. Thereafter, as shown in FIG. 31, the moving temporary support structure 42 is sent out to the side of the temporary bridge 41. The same operation is performed when the moving temporary support structure 42 on the opposite side of the temporary bridge 41 is installed. That is, the moving temporary support structure 42 is assembled in two lanes on the opposite side to the case of FIG. 30 and sent out to the side of the temporary bridge 41. Through the above operation, step S16 is completed, and the moving temporary support structures 42 are positioned on both sides of the temporary bridge 41 as shown in FIG.

  When the moving temporary support structure 42 is retracted in step S40 before moving to the new work area, as shown in FIG. 33, the pair of moving temporary support structures 42 are sufficiently placed on the side opposite to the new work area. evacuate. Then, as shown in FIG. 34, the regulation band 821 where the temporary bridge 41 exists is extended to the left side, and as shown in FIG. 35, the new bridge girder 11 from which the temporary bridge 41 has been replaced is replaced with a new construction zone. Move to the target bridge girder 11. That is, the temporary bridge 41 moves to the left by the distance of 3 spans. This operation is the second and subsequent steps S14. After the temporary bridge 41 is set as a traffic zone and the outer lane group 14 is set as a permanent restriction zone, the pair of moving temporary support structures 42 are moved to the side of the temporary bridge 41. That is, the moving temporary support structure 42 finally moves from the bridge girder 11 that has been replaced to the bridge girder 11 to be replaced in the new construction area. This operation is the second and subsequent steps S16.

  When the replacement of the bridge girder 11 in the last work zone is completed, the moving temporary support structure 42 and the temporary bridge 41 are sequentially removed by a procedure reverse to steps S14 and S16 performed first (steps S51 to S53).

  As described above, in the present embodiment, it is possible to replace the bridge girder 11 while maintaining traffic of two or more lanes. Alternatively, the plurality of bridge girders 11 can be quickly replaced by sequentially replacing the plurality of bridge girders 11 while moving the temporary bridge 41 and the moving temporary support structure 42.

  The bridge girder replacement is not limited to the above-described embodiment, and various changes can be made.

  The number of lanes of the bridge girder 11 may be four or more, for example, six lanes. In this case, two or more lanes are defined as the inner lane group 13 inside the outermost two lanes, and lanes other than the inner lane group 13 are defined as the outer lane group 14. When the number of lanes in the inner lane group 13 is three or more, the number of lanes included in the temporary bridge 41 can be three or more.

  In the dismantling of the girder 2, not the cross beam 22 of the central two sections 20, but only the cross beam 22 of any one of the central sections 20 may be removed, and the remaining part may be moved inward. That is, at least a part of the cross beam 22 located below the inner lane group 13 is removed along the longitudinal direction of the bridge girder 11, and the remaining main girder 21 and the cross beam including the portion located below the outer lane group 14 are removed. As long as 22 can be moved inward, the method of removing the cross beam 22 may be changed as appropriate.

  In the above-described embodiment, the girder 2 is first disassembled and the remaining portion is moved inward, but only the part necessary for suspending the girder support beam 423 is disassembled first, and then the girder support beam. While being supported at 423, the girder 2 may be disassembled. For example, the minimum outer cross beam 22 required to suspend the beam support beam 423 may be removed first.

  The bridge girder 11 is not limited to one that is continuous over three diameters. It may be only between one diameter or may be continuous over two or more diameters. When the bridge girder 11 continues over two or more diameters, the bridge girder 11 as a whole is replaced by repeating partial bridge girder replacement between one or a plurality of non-adjacent diameters.

  When the moving temporary support structure 42 is retracted, the moving temporary support structure 42 may be retracted to a position passing the new work area in the opposite direction to the above embodiment. Both or one of the temporary bridge 41 and the moving temporary support structure 42 may not be mobile.

  The configurations in the above-described embodiments and modifications may be combined as appropriate as long as they do not contradict each other.

DESCRIPTION OF SYMBOLS 11 Bridge girder 13 Inner lane group 14 Outer lane group 21 Main girder 22 Horizontal girder 41 Temporary bridge 42 Temporary support structure 131 Central span 132 Side span 423 Girder support beam S11-S20, S31-S41, S51-S54, S101-S105 , S111 to S115 steps

Claims (5)

It is a method of replacing bridge girders with 4 or more lanes,
a) In the traffic regulation section including the bridge girder to be replaced, stop the traffic in the inner lane group where two or more lanes are lined up on the center side of the outermost two lanes, and in the lanes other than the inner lane group Maintaining the traffic in an outer lane group;
b) A step of longitudinally cutting the bridge girder above the inner lane group and installing a temporary bridge including two or more lanes;
c) starting traffic on the temporary bridge and stopping traffic on the outer lane group;
d) installing a temporary support structure existing over the entire length of the bridge girder above the outer lane group;
e) dismantling and removing the bridge girder while using the temporary support structure, and installing a new bridge girder;
f) removing the temporary support structure from the outer lane group;
g) starting traffic on the outer lane group and stopping traffic on the temporary bridge;
h) removing the temporary bridge from the inner lane group;
i) starting traffic in the inner lane group;
A bridge girder replacement method characterized by comprising: A method for replacing a bridge girder according to claim 1,
Before the step i), further comprising the step of changing the bridge girder to be replaced to a bridge girder adjacent to the new bridge girder and repeating the steps a) to h),
In the step d) in the repeating step, the temporary support structure is moved from the new bridge girder onto the bridge girder to be newly replaced. A method for replacing a bridge girder according to claim 1,
Before the step i), further comprising the step of changing the bridge girder to be replaced to a bridge girder adjacent to the new bridge girder and repeating the steps a) to h),
In the step b) in the repeating step, the temporary bridge is moved from the new bridge girder onto the bridge girder to be newly replaced. A bridge girder replacement method according to any one of claims 1 to 3,
The bridge girder to be relocated exists across multiple spans,
In the step e), the bridge girder replacement method is characterized in that partial bridge girder replacement between one or a plurality of non-adjacent spans is repeated. A bridge girder replacement method according to any one of claims 1 to 4,
Step e)
In the span, removing at least a part of the transverse beam located below the inner lane group along the longitudinal direction of the bridge beam; and
A step of moving a main girder and a horizontal girder located below the outer lane group inwardly between the spans; and
A step of supporting a beam support beam below the main beam by the temporary support structure between the spans; and
In the span, dismantling the remaining main girder and cross beam while supporting the main girder from below with the girder support beam;
A bridge girder replacement method characterized by including:

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