Bridge replacement method

Abstract

To provide a bridge replacement method for quickly performing replacement work of an existing slab bridge to minimize impact on existing traffic.SOLUTION: A bridge replacement method that removes a superstructure of an existing bridge and replaces the same with a new superstructure, comprises a new bearing installation step for providing a new bearing device between the superstructure and a substructure which are existing, a superstructure removal step for removing the existing superstructure located above the new bearing device, and a new superstructure installation step for providing a new superstructure on the removal site of the superstructure.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a bridge replacement method in which the superstructure of an existing bridge is removed and replaced with a new superstructure. [Background technology]

[0002] In bridge reconstruction work, various construction methods have been studied for replacing deteriorated superstructures with new, more durable superstructures. For example, Patent Document 1 discloses a method for replacing an existing bridge using precast cross girders and precast vertical girders.

[0003] Specifically, after restricting general vehicle traffic on the existing bridge to be replaced and completely closing it to traffic, the existing hollow deck and steel bearings are removed. Next, precast cross girders extending perpendicular to the bridge axis are installed on substructures such as abutments and piers via a single bearing device as viewed perpendicular to the bridge axis. After this, multiple precast vertical girders are erected in parallel between adjacent precast horizontal girders in the bridge axis direction, and connecting concrete is poured between the ends of each precast vertical girder and the precast horizontal girders.

[0004] After the connecting concrete has hardened, the prestressing steel members are tensioned to unite the adjacent precast vertical beams that are erected in parallel. After the new superstructure is completed, pavement is laid across the precast cross beams and vertical beams. Finally, the road is opened to general traffic and the bridge is fully opened to traffic. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-256873 Summary of the Invention [Problem to be solved by the invention]

[0006] According to Patent Document 1, multiple precast vertical girders are erected in parallel to a precast cross girder that extends perpendicular to the bridge axis and is installed on the substructure via a single support device when viewed from the direction perpendicular to the bridge axis.This allows for a significant reduction in the number of support devices required compared to erecting precast vertical girders in parallel to the substructure via support devices, thereby achieving construction cost savings.However, due to the large number of steps involved in the replacement, the work is complicated and there is a risk of the construction period being extended.

[0007] Furthermore, when the above construction method is adopted, it is necessary to close the road to general traffic throughout the entire process, from removing the existing hollow deck and steel bearings to laying pavement on the new precast cross beams and vertical beams. Since construction work that involves traffic restrictions, such as road closures and traffic restrictions for general traffic, can have a significant impact on the surrounding traffic environment if the construction period is extended, there is a need for bridge replacement work that can shorten the time spent on traffic restrictions to minimize the impact on existing traffic.

[0008] The present invention has been made in consideration of such problems, and its main purpose is to minimize the impact on existing traffic that accompanies the replacement work of an existing bridge. [Means for solving the problem]

[0009] In order to achieve this purpose, the bridge replacement method of the present invention is a bridge replacement method in which the superstructure of an existing bridge is removed and replaced with a new superstructure, and comprises a new bearing installation process in which a new bearing device is installed between the existing superstructure and substructure, a superstructure removal process in which the existing superstructure located above the new bearing device is removed, and a new superstructure installation process in which a new superstructure is installed in the space left by the removal of the superstructure, In the superstructure removal step, the sole plate of the new bearing device is removed together with the superstructure, and in the new superstructure installation step, the sole plate is attached to the new bearing device from which the sole plate has been removed. It is characterized by:

[0010] According to the bridge replacement method of the present invention, new bearing devices are installed between the existing superstructure and substructure, the existing superstructure is then removed, and a new superstructure is installed in its place. This significantly shortens the period during which general vehicle traffic is restricted compared to when new bearing devices are installed after the existing superstructure is removed, and makes it possible to minimize the impact on the surrounding traffic environment.

[0012] Also, The superstructure can be removed quickly by simply separating the sole plate from the new bearing device and lifting the superstructure. Furthermore, the new superstructure can be installed on top of the new bearing device that has already been installed on the substructure. This shortens the work time for both the superstructure removal process and the new superstructure installation process, which require traffic restrictions for general vehicles, and significantly reduces the time spent on traffic restrictions during construction.

[0013] The bridge replacement method of the present invention includes a division process in which the superstructure is divided perpendicular to the bridge axis and multiple cross-sectional division bodies are provided, and the new superstructure is constructed from multiple new cross-sectional division bodies corresponding to the multiple cross-sectional division bodies, and in the new support installation process, the new support device is positioned in a position where each of the multiple cross-sectional division bodies can be independent, and then the superstructure removal process and the new superstructure installation process are repeated for each cross-sectional division body.

[0014] According to the replacement construction method of the present invention, the superstructure is divided into multiple sections perpendicular to the bridge axis, new bearing devices are installed so that each divided section has an independent structure, and the superstructure removal process and the new superstructure installation process are repeatedly carried out for each section. As a result, for example, if the superstructure is divided into two sections perpendicular to the bridge axis, general vehicles can pass on one side of the section while the superstructure removal process and new superstructure installation process are carried out on the other side. After this, general vehicles are switched to the other side, and the superwork removal process and new superstructure installation process are carried out on one side, making it possible to carry out so-called half-section replacement construction.

[0015] Furthermore, in the division process, the number of divisions of the superstructure can be increased depending on the width of the superstructure. Therefore, even for large bridges with wide widths, the replacement work of existing bridges can be carried out using general vehicles, making it possible to carry out bridge replacement work while minimizing the impact on the surrounding traffic environment. [Effects of the Invention]

[0016] According to the present invention, after installing a new support device between the existing superstructure and substructure, the passage of general vehicles can be restricted, the existing superstructure can be removed, and the new superstructure can be installed, thereby significantly shortening the period during which the passage of general vehicles is restricted and minimizing the impact on existing traffic. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 1 is a diagram showing an outline of a bridge replacement method (full cross-section replacement) according to an embodiment of the present invention. [Figure 2] 1 is a diagram showing details of a newly installed bearing device (movable rubber bearing device) according to an embodiment of the present invention. FIG. [Figure 3] 1 is a diagram showing an outline of a bridge replacement method (half-section replacement) according to an embodiment of the present invention (part 1). FIG. [Figure 4] FIG. 2 is a diagram showing an outline of a bridge replacement method (half-section replacement) according to an embodiment of the present invention (part 2). [Figure 5] FIG. 10 is a diagram showing another example of a newly constructed cross-sectional division body in an embodiment of the present invention. [Figure 6] 10A to 10C are diagrams showing details of the new bearing installation process in an embodiment of the present invention. [Figure 7] 10A to 10C are diagrams showing details of the upper work removal process in an embodiment of the present invention. [Figure 8] FIG. 1 is a diagram showing details of a new superstructure installation process in an embodiment of the present invention (part 1). [Figure 9] FIG. 10 is a diagram showing details of the new superstructure installation process in the embodiment of the present invention (part 2). [Figure 10]FIG. 10 is a diagram showing details of the new superstructure installation process in the embodiment of the present invention (part 3). [Figure 11] 10A and 10B are diagrams showing details of the joining process of the newly constructed cross-section division body in the embodiment of the present invention. [Figure 12] FIG. 10 is a diagram showing another example of a bridge replacement method according to an embodiment of the present invention (a case in which there is no existing bearing device). [Figure 13] 1 is a diagram showing details of a newly installed bearing device (fixed rubber bearing device) according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0018] This invention relates to bridge replacement work, particularly concrete bridge replacement work, and aims to shorten the period of traffic restrictions associated with the work and minimize the impact on existing traffic by installing new bearing devices prior to removing the superstructure (including the deck and main girders).

[0019] Below, we will explain the details of the bridge replacement method by taking as an example the case where the superstructure of a hollow deck bridge is removed and replaced with a slab girder bridge, with reference to Figures 1 to 13.

[0020] <<<<<Outline of bridge replacement method (full cross section)>>>> As shown in Fig. 1(a), an existing bridge 100 comprises a substructure 10 such as abutments and piers, a superstructure 20 including a hollow deck, and a bearing device 30 installed between the substructure 10 and the superstructure 20. In the bridge replacement method, the superstructure 20 and bearing device 30 of an existing bridge 100 with such a structure are updated using the procedure shown in Fig. 1(b).

[0021] ≪≪New support installation process and superstructure removal process≫≫ First, the bearing device 30 is removed, and a new bearing device 40 is installed at a position corresponding to the new superstructure 50. Next, the superstructure 20 is removed together with the sole plate 41 that forms part of the new bearing device 40.

[0022] <New bearing device: Movable rubber bearing device> The new bearing device 40 employs a so-called movable rubber bearing device. As shown in the view from the bridge axis direction in Figure 2(a), it is configured with a base plate 46 fixed to the substructure 10 via anchor bolts 461, and a sole plate 41 fixed to the existing superstructure 20 or the new cross-sectional division body 51 via anchor bolts 411.

[0023] A sliding plate 42 is provided on the underside of the sole plate 41, and an elastic load support 45 that contacts the underside of the sliding plate 42 is provided on the upper surface of a base plate 46. Furthermore, as shown in Figure 2(c), the upper surface of the base plate 46 is provided with a stopper 44 that is provided to surround the elastic load support 45, and side blocks 43 that are arranged in pairs on either side of the stopper 44 in the direction perpendicular to the bridge axis and that regulate the direction of movement of the sliding plate 42.

[0024] The newly installed bearing device 40 is configured so that the sliding plate 42 fixed to the sole plate 41 can move in the direction of the bridge axis on the upper surface of the elastic load support body 45, while its movement perpendicular to the bridge axis is restricted by the side blocks 43. In other words, in addition to the load transmission function of transmitting the load transmitted from the superstructure 20 to the substructure 10, it also has a displacement tracking function of following the relative displacement between the superstructure 20 and the substructure 10 that occurs during an earthquake.

[0025] 2(b), the sliding plate 42 is detachably fixed to the sole plate 41 via bolts 47. This makes it possible to easily remove the sole plate 41 from the new bearing device 40 during the superstructure removal process.

[0026] ≪≪New superstructure installation process≫≫ After the superstructure 20 is removed, as shown in Figure 1(b), first, a new sole plate 41 (or the sole plate 41 removed along with the superstructure 20) is attached to the new bearing device 40 that was left on the substructure 10 with the sole plate 41 removed. Then, a new superstructure 50 is installed on the new bearing device 40, and the load of the new superstructure 50 is transmitted to the substructure 10 via the new bearing device 40. Finally, bridge surface construction such as paving work 60 is carried out on the new superstructure 50.

[0027] According to the above procedure, the new bearing installation process is carried out before the superstructure 20 is removed, so the road closure to general vehicles only needs to be set during the superstructure removal process of removing the superstructure 20 and the new superstructure installation process of installing the new superstructure 50 and performing the paving work 60. Therefore, it is possible to significantly shorten the period during which the road is closed to general vehicles compared to when the bearing devices 30 are replaced with new bearing devices 40 after the superstructure 20 is removed.

[0028] Furthermore, if the new support installation process is carried out before the superstructure 20 is removed, not only can the new support device 40 be positioned at a location corresponding to the new superstructure 50, but the position of the new support device 40 can also be adjusted appropriately and installed at a location where so-called half-section replacement work can be carried out.

[0029] For example, in a two-lane road with one driving lane and one passing lane as shown in Figure 3(a), even if the superstructure 20 is divided into two in the direction perpendicular to the bridge axis into two cross-sectional divided bodies 21 as shown in Figure 3(b), the new bearing device 40 can be placed in a position where the driving lane side and the passing lane side are independent. In this way, for example, the cross-sectional divided body 21 on the passing lane side can be used for sharing by general vehicles, while the superstructure removal process and new superstructure installation process can be carried out on the driving lane side.

[0030] <<<<<Outline of bridge reconstruction method (cross-section division)>>>> Therefore, taking the case where a two-lane road with a driving lane and an overtaking lane is installed on the superstructure 20 of an existing bridge 100 shown in Figure 3(a) as an example, the following will explain an outline of the procedure for updating the superstructure 20 half-section at a time using the bridge replacement method, with reference to Figures 3(b) and 4.

[0031] <<New bearing installation process and division process>> First, as shown in Figure 3(b), the bearing device 30 is removed and a new bearing device 40 is installed. When the superstructure 20 is divided into two cross-sectional divided bodies 21 as described above, the new bearing device 40 is installed in a position where it can support each of the cross-sectional divided bodies 21. After this, a cutting line C extending in the bridge axis direction is drawn in the superstructure 20, and it is divided in a direction perpendicular to the bridge axis, forming the two cross-sectional divided bodies 21. Note that if the bearing device 30 is in a position where it can support each of the two cross-sectional divided bodies 21, the dividing process may be carried out prior to the new bearing installation process.

[0032] ≪≪Superstructure removal process≫≫ Next, the cross-sectional dividing body 21 on the driving lane side is removed together with the sole plate 41 that forms part of the new bearing device 40. At this time, the cross-sectional dividing body 21 on the passing lane side is left in a state in which its load is transmitted to the substructure 10 via the replaced new bearing device 40.

[0033] ≪≪New superstructure installation process≫≫ Then, as shown in Figure 4, first, a new sole plate 41 (or the sole plate 41 removed together with the cross-sectional dividing body 21) is attached to the new support device 40 that was left on the substructure 10 with the sole plate 41 removed. After this, a new cross-sectional dividing body 51 is installed in the space where the cross-sectional dividing body 21 was removed, and the load is transmitted to the substructure 10 via the new support device 40. The new cross-sectional dividing body 51 is produced by dividing the new superstructure 50 into a shape that corresponds to the cross-sectional dividing body 21.

[0034] Next, bridge surface construction such as paving work 60 is carried out on the new cross-sectional division body 51. After the cross-sectional division body 21 on the driving lane side has been replaced with the new cross-sectional division body 51 in this way, the cross-sectional division body 21 on the passing lane side is replaced with the new cross-sectional division body 51 using the same procedure.

[0035] ≪≪Joining process≫≫ Finally, adjacent cross-sectional sections 21 are joined in the direction perpendicular to the bridge axis while ordinary vehicles continue to travel, and the new superstructure 50 is constructed. By updating the superstructure 20 half-section at a time in this way, construction traffic restrictions implemented during the construction period can be limited to lane restrictions rather than road closures to ordinary vehicles.

[0036] In other words, during the work of replacing the cross-sectional divider 21 on the driving lane side with the new cross-sectional divider 51, lane traffic regulations are implemented to allow general vehicles to pass using the cross-sectional divider 21 on the passing lane side. Next, the lane traffic regulations are switched to allow general vehicles to pass using the new cross-sectional divider 51 constructed on the driving lane side, and the work of replacing the cross-sectional divider 21 on the passing lane side with the new cross-sectional divider 51 is carried out.

[0037] In this way, the replacement work of the existing bridge 100 can be carried out using common vehicles, thereby minimizing the impact on existing traffic.

[0038] 3 and 4, only one cutting line C extending in the bridge axis direction is set on the superstructure 20, dividing it into two in the direction perpendicular to the bridge axis, and providing two cross-sectional dividing bodies 21. However, the number of divisions is not limited to this, and two or more cutting lines C may be set depending on the width of the superstructure 20 to divide it into multiple parts in the direction perpendicular to the bridge axis, and multiple cross-sectional dividing bodies 21 may be provided.

[0039] Furthermore, as shown in Figure 5(a), by adjusting the installation position of the new support device 40 so that it can support the cross-sectional dividing body 21, the installation position may not match the T-shaped cross-section main girder 52 of the new cross-sectional dividing body 51 to be installed in the space where the cross-sectional dividing body 21 is removed.

[0040] In this case, as shown in Figure 5(b), a cross beam 53 is provided to connect the adjacent T-shaped cross-section main girders 52 of the newly constructed cross-section divided body 51. The cross beam 53 may then be used to connect the newly constructed cross-section divided body 51 and the newly constructed support device 40.

[0041] <<<<Details of Bridge Reconstruction Method (Cross-Section Division)>>>> The detailed procedures for the new bearing installation process, division process, superstructure removal process, new superstructure installation process, and joining process carried out in the above bridge reconstruction method (section division) are explained below using an example in which the superstructure 20 is divided into two and each half section is replaced, similar to the outline of the above method. Note that even when the bridge reconstruction method is carried out on the entire section, the new bearing installation process, superstructure removal process, and new superstructure installation process can be carried out in the same procedures.

[0042] ≪≪Preparation work≫≫ Before starting the replacement work, as shown in Figure 7(a), temporary support structures S are installed below the superstructure 20 so as to connect adjacent substructures 10. In addition, advance preparations are carried out in advance, such as fabricating the new support devices 40 described above, determining the installation positions of the new support devices 40, and fabricating the new cross-sectional dividing bodies 51 (segments 511).

[0043] <<Setting the installation position of the new bearing device>> As explained in Figure 3(b), when a cutting line C is set in the bridge axis direction on the superstructure 20 to form two adjacent cross-sectional division bodies 21 perpendicular to the bridge axis, the installation position of the new support device 40 capable of supporting these is determined in advance.

[0044] <<Production of new cross-sectional division bodies (segments)>> As explained in Figure 4, the new superstructure 50 is constructed by joining together a plurality of new cross-sectional division bodies 51 corresponding to the cross-sectional division bodies 21, and the new cross-sectional division bodies 51 are fabricated in advance at a factory. In this embodiment, since the existing bridge 100, which is a hollow deck bridge, is to be replaced with a post-tensioned slab girder bridge, the new cross-sectional division bodies 51 are constructed from precast members equipped with a plurality of main girders 52 with T-shaped cross sections.

[0045] When viewed from the direction perpendicular to the bridge axis, the new cross-sectional division body 51 is composed of multiple segments 511 that are continuous in the bridge axis direction. At least four types of these multiple segments 511 are prepared in accordance with their placement positions.

[0046] Specifically, as shown in Figure 9(a), there are four types: a standard segment 511a placed between the spans; an end support segment 511b placed on the abutment 11 of the substructure 10; a support segment 511c placed on the pier 12; and a pair of support side segments 511d placed on both sides of the support segment 511c.

[0047] Of the four types of segments 511, the end support segment 511b and the support segment 511c are each provided with a cross beam 54. Furthermore, a sheath pipe (not shown) that penetrates in the bridge axis direction is embedded in each of all segments 511. There are two types of sheath pipes: one that houses primary steel members 55 as shown in Figures 9(a) and 10(a), and one that houses secondary steel members 56 as shown in Figures 9(b) and 10(b).

[0048] ≪≪New support installation process≫≫ After carrying out the above preparatory work, the new bearing installation process described in Figure 3(b) is carried out in the following procedure.

[0049] First, as shown in Figure 6(a), multiple jacks J are set at appropriate positions between the superstructure 20 and the substructure 10, and the load of the superstructure 20 is transmitted from the bearing device 30 to the substructure 10 via these multiple jacks J. Next, the area of ​​the substructure 10 near the predetermined planned installation position of the new bearing device 40 is chipped away to ensure installation space 70 for the new bearing device 40.

[0050] This installation space 70 also serves as a work space for workers to install the new bearing device 40 and remove the existing bearing device 30. For this reason, a wide opening is ensured for the installation space 70. The installation space 70, which also serves as a work space, is used to form anchor holes 22 on the underside of the superstructure 20. Anchor bolts 411, as shown in Figure 2(a), used when installing the sole plate 41 of the new bearing device 40 are fixed into the anchor holes 22.

[0051] 6(b), the existing bearing device 30 is removed and a platform M is placed in the installation space 70. The platform M is used to install the new bearing device 40 at a predetermined height. After this, non-shrink mortar or epoxy resin is filled between the anchor holes 22 and the anchor bolts 411, and the sole plate 41 is installed on the underside of the superstructure 20.

[0052] 6(c), a new bearing device 40 with its sole plate 41 removed is installed on the platform M, and as shown in FIG. 6(d), the installation space 70 is reinforced as necessary and then filled with a filler F such as mortar or concrete. Also, as shown in FIG. 2(b), a sliding plate 42 is installed on the sole plate 41 via bolts 47. This installs the new bearing device 40 between the superstructure 20 and the substructure 10, so the jack J is removed and the load of the superstructure 20 is transmitted to the substructure 10 via the new bearing device 40. This process is repeated until all bearing devices 30 have been removed and replaced with new bearing devices 40.

[0053] ≪≪Dividing process≫≫ Once the new bearing device 40 has been installed, the process of dividing the superstructure 20, as explained in Figure 3(b), is carried out. The cross-section dividing work of the superstructure 20 can be carried out by any means as long as the cutting line C can be set in the bridge axis direction. Since the two cross-section dividing bodies 21 formed in this way are independent of each other, the cross-section dividing body 21 on the passing lane side is used first to allow general vehicles to share it, while the superstructure removal process begins on the driving lane side.

[0054] ≪≪Superstructure removal process≫≫ After construction traffic restrictions are put in place to allow general vehicles to use the passing lane, the superstructure removal process described in Figure 3(b) is carried out using the following procedure: First, as shown in Figure 7(b), multiple cutting lines extending perpendicular to the bridge axis are drawn on the cross-sectional divided body 21 created in the dividing process, to form multiple divided blocks 23 large enough to be stacked on the loading platform of the transport vehicle V.

[0055] Around the same time, a lifting device 80 is installed to be used for transporting the divided block 23. Any device may be used for the lifting device 80 as long as it has the function of lifting the divided block 23 and loading it onto the transport vehicle V. In Figure 7(b), a device is used in which a front vent 81 and a rear vent 82 are installed on either side of the cross-sectional divided body 21 in the bridge axis direction, an erection girder 83 is erected between them, and a lifting device 84 is provided that moves along this erection girder 83.

[0056] Using this erection girder 83 and the lifting device 84, as shown in Figure 7(c), a plurality of divided blocks 23 are lifted in sequence, then loaded onto a transport vehicle V, and carried out by the transport vehicle V. In this way, all of the divided blocks 23 formed by dividing the cross-sectional divided body 21 located on the travel lane side are removed.

[0057] Of the divided blocks 23 that were transported and removed, those that were located on the substructure 10 have the sole plate 41 of the new bearing device 40 that was installed in the new bearing installation process fixed to them, as shown in Figure 8(a). For this reason, when removing the divided blocks 23, the bolts 47 that join the sole plate 41 and sliding plate 42 of the new bearing device 40 are removed in advance.

[0058] This allows the sole plate 41 to be easily separated from the new bearing device 40, and the divided block 23 with the sole plate 41 installed can be removed without much effort. This makes it possible to quickly remove the divided block 23, which contributes to shortening the time required for removing the cross-sectional divided body 21.

[0059] ≪≪New superstructure installation process≫≫ Once the cross-sectional dividing body 21 on the travel lane side has been removed, the new superstructure installation process described with reference to FIG. 4 is carried out in the following procedure.

[0060] First, as shown in Figure 8(b), a new sole plate 41 is installed via bolts 47 on the sliding plate 42 of the new bearing device 40 that has been left in the substructure 10 and from which the sole plate 41 has been removed, and the new bearing device 40 is reassembled. When assembling the new bearing device 40, the sole plate 41 that was removed together with the divided block 23 may be reused, or a new sole plate 41 may be prepared separately and used for assembly.

[0061] After assembling the new support device 40, the lifting device 80 used in the superstructure removal process is used to place the new cross-section division body 51 in the space vacated by the removal of the cross-section division body 21. As mentioned above, the new cross-section division body 51 comprises four types of segments 511 (standard segment 511a, end support segment 511b, support segment 511c, and support side segment 511d). Therefore, from these four types, a segment 511 that corresponds to the placement position is appropriately selected and placed.

[0062] At this time, since the end support segment 511b will be placed on the abutment 11, anchor holes 57 as shown in Figure 8(c) are made in advance. Then, when installing the end support segment 511b, anchor bolts 411 provided in the sole plate 41 are inserted into these anchor holes 57 and the segment is placed on the new support device 40. In this state, the anchor holes 57 are filled with non-shrinkage mortar, and the sole plate 41 is installed on the underside of the end support segment 511b. These operations are also performed in the same way for the support segment 511c to be placed on the pier 12.

[0063] After the segments 511 are placed, first, as shown in Figure 9(a), prestress is introduced to the primary steel members 55 inserted into the sheath tubes (not shown) of the multiple standard segments 511a on one side (the left side of the paper) of the pier 12. Before, after, or at the same time as this, prestress is introduced to the primary steel members 55 inserted into the sheath tubes (not shown) of the support side segments 511d that are paired with the support segment 511c and the pier 12 on either side.

[0064] 9(b), filler material 58 is injected into the adjustment joints provided between the standard segment 511a and the end support segment 511b and the support side segment 511d. After this, prestress is introduced into the secondary steel material 56 inserted into the sheath tubes (not shown) of the end support segment 511b, the multiple standard segments 511a, the support segment 511c, and the support side segment 511d.

[0065] 10(a), prestress is introduced by tensioning the primary steel members 55 inserted into the sheath tubes (not shown) of the multiple standard segments 511a on the other side (the right side of the paper) of the pier 12. Then, as shown in FIG. 10(b), filler material 58 is injected into the adjustment joints provided between the standard segment 511a and the end support segment 511b and the support side segment 511d.

[0066] Finally, the secondary steel material 56 having a sheath tube (not shown) inserted across the end fulcrum segment 511b, multiple standard segments 511a, fulcrum segment 511c, fulcrum side segment 511d, and one standard segment 511a adjacent to the fulcrum side segment 511d on one end side (left side of the paper) sandwiched between the pier 12 is tensioned to introduce prestress.

[0067] 9 and 10 show an example of two spans, but in the case of three or more spans, the work in Fig. 9(a) and (b) is repeated for each span in turn (from left to right on the page) to introduce prestress. After this, the work in Fig. 10(a) and (b) can be carried out.

[0068] In this way, as shown in Figure 4, a new cross-sectional division body 51 is constructed on the traveling vehicle side, and its load is transmitted to the substructure 10 via the new bearing device 40. Then, bridge surface construction such as paving work 60 is carried out on this new cross-sectional division body 51.

[0069] As a result, ordinary vehicles are allowed to pass on the driving lane side on the new cross-sectional dividing body 51, so the lane traffic regulations are switched to restrict the passage of ordinary vehicles only to the driving lane side. After this switching, the cross-sectional dividing body 21 on the passing lane side is removed using the above procedure, and the new cross-sectional dividing body 51 is constructed in its place.

[0070] ≪≪Joining process≫≫ Once the new cross-sectional divided bodies 51 have been constructed on both the driving lane side and the passing lane side, the joining process of the new cross-sectional divided bodies 51 explained in FIG. 4 is carried out in the following procedure.

[0071] As shown in Figure 11, shear cotters are formed on each of the opposing surfaces 512 of adjacent new cross-section dividing bodies 51 in the direction perpendicular to the bridge axis. In addition, connecting rebars 513 are protruded from each of the opposing surfaces 512 in the direction perpendicular to the bridge axis to form so-called gap lap joints. Then, filler material 514 is filled between the opposing surfaces 512 so that the connecting rebars 513 are buried. If room-temperature-setting ultra-high-strength fiber-reinforced concrete is used as the filler material 514, it can demonstrate high strength without thermal curing, allowing for rapid construction.

[0072] According to the bridge replacement method described above, after installing new bearing devices 40 between the existing superstructure 20 and substructure 10, general vehicle traffic can be restricted, the existing superstructure 20 can be removed, and the new superstructure 50 can be installed in the space left by the removal. This significantly shortens the period during which general vehicle traffic is restricted.

[0073] Furthermore, by appropriately adjusting the installation position of the new bearing device 40, it is also possible to carry out so-called half-section replacement work. This allows the replacement work of the existing bridge 100 to be carried out while sharing with general vehicles, minimizing the impact on existing traffic.

[0074] <<<Method for replacing an existing bridge where there are no existing bearing devices>>> 1 to 11 above, an existing bridge 100 is shown as an example in which an existing bearing device 30 is interposed between the existing superstructure 20 and substructure 10. However, the bridge replacement method is not limited to this, and can also be applied to an existing bridge 100 in which no existing bearing device 30 exists.

[0075] For example, as shown in Figure 12(a), if a so-called Menase hinge reinforcing bar 110 is installed between the superstructure 20 and the substructure 10, the Menase hinge reinforcing bar 110 can be cut and a new bearing device 90 can be installed during the new bearing installation process. A fixed rubber bearing device is used for the new bearing device 90.

[0076] <New bearing device: fixed rubber bearing device> As shown in the view from the bridge axis direction in Figure 13(a), the new bearing device 90 comprises a base plate 96 fixed to the substructure 10 via anchor bolts 961, and a sole plate 91 fixed to the existing superstructure 20 or the new cross-sectional dividing body 51 via anchor bolts 911. An upper shoe 92 is provided on the underside of the sole plate 91, and a lower shoe 95 is provided on the top surface of the base plate 96.

[0077] Furthermore, a through-hole is provided in the center of the lower shoe 95, and the lower end of the base 93 is inserted into this through-hole. Then, as shown in Figure 13(c), a doughnut-shaped elastic load support plate 94 is attached to the base 93 and passes through it, with its lower surface abutting against the upper surface of the lower shoe 95. Also, the upper surface of the elastic load support plate 94 abuts against the lower surface of the upper shoe 92, and the upper end of the base 93 penetrates into the upper shoe 92 as shown in Figures 13(a) and 13(b).

[0078] The newly constructed support device 90 configured in this manner uses an elastic load support plate 94 to support the vertical force transmitted from the superstructure 20, and a bolt 93 to resist horizontal forces in all directions caused by relative displacement between the superstructure 20 and the substructure 10 during an earthquake.

[0079] 13(b), the upper shoe 92 is removably fixed to the sole plate 91 via a bolt 97. This makes it possible to easily remove the sole plate 91 from the new bearing device 90 during the superstructure removal process.

[0080] <<New bearing installation process: When there is no existing bearing device 30>> The procedure for installing the new bearing device 90 is as follows: First, as shown in Figure 12(a), a bracket 13 is constructed on the side of the substructure 10, and a jack J is installed on top of it. With the load of the superstructure 20 being transmitted to the substructure 10 via the jack J and bracket 13, the Menze hinge reinforcing bar 110 is cut.

[0081] 12(b), the area near the planned installation position of the new bearing device 40 is chipped away to secure the installation space 70, and the upper end of the substructure 10 is chipped away to match the height of the new bearing device 40. After this, epoxy resin or non-shrink mortar is filled between the anchor holes 22 and anchor bolts 911 provided on the underside of the superstructure 20, and the sole plate 91 is installed on the underside of the superstructure 20.

[0082] Furthermore, a new bearing device 90 with its sole plate 91 removed is installed on a platform M installed in the installation space 70, and as shown in FIG. 12(c), the installation space 70 is reinforced as necessary and then filled with a filler material F such as mortar or concrete. Furthermore, as shown in FIG. 13(b), an upper shoe 92 is installed on the sole plate 91 via a bolt 97. As a result, the new bearing device 90 is installed between the superstructure 20 and the substructure 10, and the jack J and bracket 13 are removed to transmit the load of the superstructure 20 to the substructure 10 via the new bearing device 90. Thereafter, the superstructure removal process and the new superstructure installation process are as described above.

[0083] The bridge reconstruction method of the present invention is not limited to the above-described embodiment, and various modifications are possible within the scope of the present invention.

[0084] For example, in this embodiment, the bridge replacement method has been described using an example in which the existing bridge 100 is a hollow deck bridge and is replaced with a slab girder bridge. However, the bridge replacement method is not limited to this and can be applied to any type of bridge as long as it is made of concrete both before and after replacement.

[0085] 2 illustrates a new bearing device 40 made up of a movable rubber bearing device, and FIG. 13 illustrates a new bearing device 90 made up of a fixed rubber bearing device. However, the structures are not limited in any way, and either structure may be adopted as long as it functions as a movable rubber bearing device or a fixed rubber bearing device.

[0086] Furthermore, in this embodiment, when the existing bearing device 30 is removed and a new bearing device 40 is installed, a movable rubber bearing device is used as the new bearing device 40. However, if the existing bearing device 30 is a fixed rubber bearing device, the fixed rubber bearing device described with reference to Figure 13 may be used as the new bearing device 40. [Explanation of symbols]

[0087] 100 Existing bridges 10 Substructure 11 Abutment 12 Bridge Pier 20 Superstructure 21 Sectional division body 22 Anchor holes 23 Split Block 30 Bearing device 40 Newly installed bearing device 41 Soleplate 411 Anchor Bolt 42 Sliding Plate 43 Side Block 44 Stopper 45 Elastic Load Support 46 base plate 461 Anchor Bolt 47 volts 50 New superstructure 51 Newly constructed cross-sectional division body 511 segments 511a Standard Segment 511b End Support Segment 511c Fulcrum Segment 511d Support side segment 512 Opposite surface 513 Jointed reinforcing bars 514 Filling material 52 Main digit 53 Side beam 54 Side beam 55 Primary steel material 56 Secondary steel materials 57 Anchor hole 58 Filling material 60 Paver 70 Installation space 80 Lifting equipment 81 forward vent 82 rear vent 83 Erection Girder 84 Lifting device 90 Newly installed bearing device 91 Soleplate 911 anchor bolt 92 Kamikutsu 93 Shinbou 94 Elastic Load Support Plate 95 Shimotsutsu 96 base plate 961 Anchor Bolt 97 volts 100 Existing bridges C cutting line J jack M mount F Filling material V Transport vehicle

Claims

1. This is a bridge replacement method in which the superstructure of an existing bridge is removed and replaced with a new superstructure. a new bearing installation process for installing a new bearing device between the existing superstructure and substructure; a superstructure removal process of removing the existing superstructure located above the newly installed bearing device; A new superstructure installation process for installing a new superstructure on the site where the superstructure has been removed, In the superstructure removal process, the sole plate of the newly installed bearing device is removed together with the superstructure; A bridge replacement method characterized in that, in the new superstructure installation process, the sole plate is attached to the new support device from which the sole plate has been removed.

2. In the bridge replacement method described in claim 1, A dividing step is provided in which the superstructure is divided in a direction perpendicular to the bridge axis to provide a plurality of cross-sectional divided bodies; The new superstructure is composed of a plurality of new cross-sectional division bodies corresponding to the plurality of cross-sectional division bodies, In the new bearing installation step, the new bearing device is disposed at a position where each of the plurality of cross-sectional divided bodies can be independent, and then A bridge replacement method characterized by repeating the superstructure removal process and the new superstructure installation process for each cross-sectional divided body.

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