Movement restriction device for jack-up and bearing replacement method

Abstract

To provide a movement restriction device for jack up and a bearing replacing method which can resist earthquake even in a state where a (bridge-) bearing is removed after jacking up.SOLUTION: A movement restriction device for jack up 1 comprises: an inner member 2 supported by either one of an upper structure or a lower structure; and an outer member 3 supported by the other. The inner member 2 is provided with: a plate-like inner plate part 20; and jack surrounding parts 21 erected on the inner plate part 20 so as to be spaced away from and surrounds the jack. The outer member 3 is provided with: a tabular outer plate part 30; and an outer surrounding parts 31 erected on the outer plate part 30 so as to be spaced away from and surrounds the jack surrounding parts 21. The jack surrounding parts 21 are fitted to the outer surrounding parts 31, respectively, so that the upper structure is restricted from moving horizontally during earthquake.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a jack-up movement restriction device that jacks up a superstructure such as a bridge girder and restricts its movement when replacing an existing bridge bearing with a new bearing, and a bearing replacement method that uses the same to replace an existing bridge bearing with a new bearing. [Background technology]

[0002] Traditionally, when replacing bridge bearings, concrete or steel brackets are attached to the substructure to increase the space in the piers and abutments, and the superstructure, such as the bridge girders, is then jacked up to remove the stress acting on the existing bearings, and the existing bearings are then replaced with new ones.

[0003] On the other hand, when replacing bridge bearings, measures must be taken to ensure that the bridge can resist horizontal seismic forces (for example, Level 1 earthquake forces) even when the bearings are removed, and currently this is addressed by removing every other bearing in a staggered pattern rather than replacing all adjacent bearings at once. However, this means that it takes more than twice the time to remove the bearings, which increases the number of days required for construction.

[0004] For example, Patent Document 1 discloses a method for updating an existing bearing device in which an existing bearing device on a substructure 4 is removed and a new bearing device is installed, in which grooves 15 are formed on the side surface 12 or underside 13 of the existing concrete girder 1 so as not to chip the internal reinforcing bars 14 of the existing concrete girder 1, and an engaging fitting 24 having a protrusion 22 that fits into said groove 15 is provided on the existing concrete girder 1 so that said protrusion 22 fits into said groove 15, and the existing concrete girder 1 is supported by a new bearing device 21 via said engaging fitting 24 (see claim 1 in the scope of claims of Patent Document 1, paragraphs

[0013] to

[0023] of the specification, and Figures 1 to 5 of the drawings, etc.).

[0005] However, the method of updating existing bearing devices described in Patent Document 1 does not take into consideration countermeasures in the unlikely event that horizontal earthquake forces act upon the bearings when they are removed, and as mentioned above, the only possible countermeasure is to remove every other bearing in a staggered pattern, which does not solve the problem of the number of days required for construction.

[0006] Furthermore, Patent Document 2 discloses a method for replacing a seismic isolation device, in which when replacing an existing seismic isolation device with a new one, a temporary support device consisting of a flat jack 1 and a temporary bearing 11 is provided to support the upper layer in place of the existing seismic isolation device, thereby making it possible to suppress vibrations of a structure caused by an earthquake even if an earthquake occurs during the replacement of the seismic isolation device (see claim 1 in the scope of claims of Patent Document 2, paragraphs

[0040] to

[0055] of the specification, Figures 1 to 6 of the drawings, etc.).

[0007] However, the method for replacing a seismic isolation device described in Patent Document 2 requires the installation of temporary support devices consisting of flat jacks 1 and temporary bearings 11 on both the front, back, left and right sides of each seismic isolation device, which requires a large amount of space around the existing bearings of the substructure, and there is the problem that it is difficult to secure this space.In addition, the method for replacing a seismic isolation device described in Patent Document 2 requires the separate installation of special flat jacks 1 and temporary bearings 11, which also poses the problem of increased costs. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-19493 [Patent Document 2] Japanese Patent Application Publication No. 2017-57636 Summary of the Invention [Problem to be solved by the invention]

[0009] The present invention was devised in consideration of the above-mentioned problems, and its purpose is to provide a movement limiting device for jacking up that can withstand earthquakes when the structure is jacked up and the supports are being removed, and a method for replacing supports using the same. [Means for solving the problem]

[0010] The jack-up movement limiting device according to claim 1 is When replacing bridge bearings, It is installed around the jacks that are supported by the bridge substructure and lift the superstructure, and limits the movement of the superstructure during an earthquake. and can withstand horizontal forces during earthquakes. A movement limiting device for jacking up, comprising an inner member supported on either the upper structure or the lower structure, and an outer member supported on the other, wherein the inner member has a flat inner plate portion and a jack surrounding portion that is erected on the inner plate portion and surrounds the jack at a distance, and the outer member has a plate-shaped outer plate portion and an outer surrounding portion that is erected on the outer plate portion and surrounds the jack surrounding portion at a distance, and the jack surrounding portion and the outer surrounding portion fit together to limit horizontal movement of the upper structure during an earthquake.

[0011] The movement limiting device for jacking up described in claim 2 is characterized in that, in the movement limiting device for jacking up described in claim 1, the jack surrounding portion abuts against the outer plate portion to limit the vertical movement of the superstructure during an earthquake.

[0012] The movement limiting device for jacking up described in claim 3 is characterized in that, in the movement limiting device for jacking up described in claim 1 or 2, a slit is formed in either or both of the jack surrounding portion and the outer surrounding portion through which the hydraulic hose of the jack is inserted.

[0013] The movement limiting device for jacking up described in claim 4 is a movement limiting device for jacking up described in any of claims 1 to 3, characterized in that a sliding material for reducing friction is attached to the inside of the inner plate portion or the outer plate portion attached to the superstructure.

[0014] The movement limiting device for jacking up according to claim 5 is the movement limiting device for jacking up according to any one of claims 1 to 4, characterized in that a reinforcing rib is formed on the outside of the outer surrounding portion.

[0015] The movement limiting device for jacking up described in claim 6 is characterized in that, in the movement limiting device for jacking up described in any of claims 1 to 5, a height adjustment filler corresponding to the slope of the underside of the superstructure is interposed between the inner plate portion or the outer plate portion attached to the superstructure and the superstructure.

[0016] The bearing replacement method described in claim 7 is a bearing replacement method for replacing an existing bearing of a bridge with a new bearing, characterized in that a jack-up movement limiting device described in any of claims 1 to 6 is installed, the superstructure of the bridge is jacked up with a jack to replace the existing bearing with a new bearing, and then the jack-up movement limiting device is removed. Furthermore, the jack-up movement limiting device described in claim 8 is a temporary jack-up movement limiting device that is installed around a jack that is supported on the substructure of a bridge and lifts the superstructure when the bridge's bearings are replaced, limits the movement of the superstructure during an earthquake, and can be removed after the bearings are replaced. The device comprises an inner member supported on either the superstructure or the substructure, and an outer member supported on the other, wherein the inner member has a flat inner plate portion and a jack surrounding portion that is erected on the inner plate portion and surrounds the jack at a distance, and the outer member has a plate-shaped outer plate portion and an outer surrounding portion that is erected on the outer plate portion and surrounds the jack surrounding portion at a distance, and the jack surrounding portion and the outer surrounding portion are fitted together to limit the horizontal movement of the superstructure during an earthquake. [Effects of the Invention]

[0017] Claim 1~ 8 According to the invention, when replacing bridge supports, even if a bridge is subjected to seismic force, it is possible to resist the horizontal force and limit the horizontal movement of the superstructure when the bridge is jacked up and the supports are removed.

[0018] In particular, according to the invention of claim 2, the jack surrounding portion abuts against the outer plate portion, thereby restricting the vertical movement of the superstructure during an earthquake, thereby not only restricting horizontal movement but also minimizing the falling and tilting of the superstructure.

[0019] In particular, according to the invention of claim 3, a slit is formed through which the hydraulic hose of the jack is inserted, so there is little risk that the hydraulic hose will get in the way and interfere with the jacking up operation, so the jacking up operation can be carried out safely and the stress input during, for example, a level 1 earthquake can be resisted.

[0020] In particular, according to the invention of claim 4, a sliding material that reduces friction is attached to the inside of the outer plate portion, so that it is possible to respond to the temperature expansion and contraction of the upper structure during jacking up.

[0021] In particular, according to the invention as defined in claim 5, since reinforcing ribs are formed, it is possible to reliably resist the horizontal force of an earthquake.

[0022] In particular, according to claim 6, the height-adjusting filler is installed, so the other inner and outer members can be made common regardless of the gradient of the bridge superstructure, thereby achieving cost reduction of the jack-up movement restriction device. [Brief explanation of the drawings]

[0023] [Figure 1] FIG. 1 is a side view of a jack-up movement restriction device according to an embodiment of the present invention, as viewed in a direction perpendicular to the bridge axis, with the device placed on a jack-up bracket. [Figure 2] 2 is a horizontal cross-sectional view of the jack-up movement limiting device of FIG. 1 taken along line AA. [Figure 3] FIG. 3 is a diagram showing only the inner member of the movement restricting device for jacking up, where (a) is a plan view, (b) is a vertical cross-sectional view taken along line BB, and (c) is a top perspective view looking down from above. [Figure 4] FIG. 4 shows only the outer member of the jack-up movement restriction device 1, where (a) is a plan view, (b) is a vertical cross-sectional view taken along line CC, and (c) is a perspective view of the bottom surface with the device turned upside down. [Figure 5]FIG. 5 is a flowchart showing each work step of the bearing replacement method according to the embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0024] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A jack-up movement restriction device and a bridge bearing replacement method using the same according to an embodiment of the present invention will be described in detail below with reference to the drawings.

[0025] <Movement restriction device for jacking up> First, a jack-up movement limiting device 1 according to an embodiment of the present invention will be described with reference to Figures 1 to 4. Figure 1 is a side view of the jack-up movement limiting device 1 according to an embodiment of the present invention, placed on a jack-up bracket B2, viewed in a direction perpendicular to the bridge axis. Figure 2 is a horizontal cross-sectional view of the jack-up movement limiting device 1 shown in Figure 1, taken along line AA. Figure 3 shows only the inner member of the jack-up movement limiting device 1, with (a) being a plan view, (b) being a vertical cross-sectional view taken along line BB, and (c) being a perspective top view viewed from above. Figure 4 shows only the outer member of the jack-up movement limiting device 1, with (a) being a plan view, (b) being a vertical cross-sectional view taken along line CC, and (c) being a perspective bottom view with the device turned upside down.

[0026] Here, the illustrated bridge B1 has a superstructure, a bridge girder BG made of steel girders, installed on top of a substructure, a pier P1, made of reinforced concrete, via bearings not shown.When replacing the existing bearing with a new bearing, the bridge is jacked up with a jack device J1 to remove stress from the existing bearing, and this will be explained as an example in which a jack-up movement restriction device 1 is used.

[0027] The jack-up bracket B2 is an additional bracket for mounting the jack device J1, which is supported by bolts attached to the side of the pier P1, which is the substructure of the bridge B1. The parallel overhead lines shown by the dashed dotted lines in Figure 2 indicate the bottom flange H1 of the steel girder, and the central overhead double circle shown by the dashed dotted lines in Figures 2 to 4 indicates the position where the jack device J1, which lifts the bridge girder BG, will be installed.

[0028] 1 to 4, the jack-up movement limiting device 1 according to this embodiment includes an inner member 2 attached to the upper surface of a jack-up bracket B2, and an outer member 3 attached to the underside of the bottom flange H1 of a bridge girder BG, which is the superstructure, facing the inner member 2. This jack-up movement limiting device 1 is a temporary device used while work is being carried out to replace the bridge B1's bearings by lifting the superstructure, including the bridge girder BG, of the bridge B1 with a jack device J1 supported on the substructure, and is a movement limiting device that resists, for example, a level 1 earthquake that occurs during the work, and takes over part of the function of the bridge B1's bearings, limiting the horizontal and vertical movement of the bridge girder BG, which is the superstructure.

[0029] (Inner member) As shown in Figures 2 and 3, the inner member 2 has a rectangular, flat inner plate portion 20 and a jack surrounding portion 21 that stands on the inner plate portion 20 and surrounds the jack device J1 at a distance.

[0030] As shown in FIG. 3(a), the inner plate portion 20 is a rectangular (oblong) steel plate of a predetermined thickness that can withstand collision loads, and has bolt holes 22 drilled at the longitudinal ends for bolting to the jack-up bracket B2.

[0031] However, the inner member 2 may be configured to have no bolt holes 22, and the inner plate portion 20 and the upper plate of the jack-up bracket B2 may be clamped with a vice or the like to be fixed to the jack-up bracket B2.

[0032] 3(a) to 3(c), the jack surrounding portion 21 is a portion consisting of a rectangular cylindrical wall body that is rectangular in plan view (rectangular in horizontal cross section) and is formed so as to surround the jack device J1 at a distance from the jack device J1, and has slits 23 formed therein for inserting hydraulic hoses of the jack device J1. In this embodiment, the jack surrounding portion 21 has a total of four slits 23 formed near the center so as to be close to the circular outer diameter of the jack device J1, allowing hydraulic hoses to be inserted from various directions.

[0033] 3(a) and 3(c), the jack surrounding portion 21 is formed by four wall bodies that are V-shaped in plan view and spaced apart across four slits 23 so as to surround the jack device J1. Therefore, there is little risk that the hydraulic hoses of the jack device J1 will get in the way and interfere with the jacking-up operation of the jack device J1, and the jacking-up operation can be carried out safely.

[0034] 1, the jack surrounding portion 21 is provided at a predetermined distance in the vertical direction from the outer plate portion 30 of the outer member 3 described below. Therefore, even in the unlikely event that the jack device J1 falls over due to horizontal force during an earthquake while jacking up the superstructure with the jack device J1, the jack surrounding portion 21 and the outer plate portion 30 come into contact with each other, thereby restricting vertical downward movement and minimizing the falling and tilting of the superstructure.

[0035] (Outer member) As shown in FIGS. 2 and 4, the outer member 3 has a plate-shaped outer plate portion 30 and an outer surrounding portion 31 standing on the outer plate portion 30.

[0036] As shown in Figure 4(a), the outer plate portion 30 is an octagonal (rectangular) steel plate of a predetermined thickness that can withstand collision loads, and has bolt holes 32 drilled at the end in the longitudinal direction (in the bridge axis direction in the illustrated case) for bolting to the lower flange H1 of the bridge girder BG, which is the superstructure.

[0037] However, the outer member 3 may be configured without the bolt holes 32, and the outer plate portion 30, the height adjustment filler 4, and the lower flange H1 of the bridge girder BG may be clamped and fixed to the lower flange H1 using a vice or the like. This is because there is no need to drill bolt holes that would result in a cross-sectional defect in the lower flange H1, which is the superstructure of the bridge B1.

[0038] 2, the outer surrounding portion 31 is a rectangular cylindrical wall portion having a rectangular horizontal cross section (rectangular in plan view) that is spaced apart from the jack surrounding portion 21 of the inner member 2 and that surrounds the jack surrounding portion 21, and has slits 33 formed therein for accessing the jack device J1. In this embodiment, the outer surrounding portion 31 has two slits 33 formed near the center that are close to the circular outer diameter of the jack device J1, so that the jack device J1 can be accessed from two directions. In other words, as shown in FIGS. 2 and 4, the outer surrounding portion 31 is formed so that a pair of symmetrical walls that are V-shaped in plan view face each other with the two slits 33 between them.

[0039] In this way, two large slits 33 are formed in the outer surrounding portion 31, making it easier to access the upper part of the jack device J1, thereby improving work efficiency when jacking up the jack device J1.

[0040] 4(a) to 4(c), a plurality of triangular reinforcing ribs are formed on the outside of the outer surrounding portion 31 to resist collision loads when the jack surrounding portion 21 and the outer surrounding portion 31 collide during an earthquake. A central reinforcing rib 34 is formed on the outside of the center in the short direction of a pair of V-shaped walls of the outer surrounding portion 31 in a plan view, and end reinforcing ribs 35 are formed on the outside of each of the pair of V-shaped walls near the slits 33.

[0041] Although the jack surrounding portion 21 and the outer surrounding portion 31 have been described as being rectangular in horizontal cross section, the jack surrounding portion 21 and the outer surrounding portion 31 may be cylindrical portions with similar horizontal cross sections that fit together with a predetermined gap between them. For example, the jack surrounding portion 21 and the outer surrounding portion 31 may be cylindrical portions.

[0042] (Sliding material) As shown in Figures 4(a) and 4(c), a sliding member 5 that reduces friction between the outer plate portion 30 of the outer member 3 and the jacking device J1 is attached to the inner surface (lower surface) of the outer plate portion 30 and the shaded area inside the outer surrounding portion 31. The sliding member 5 in this embodiment is a plate material made of fluororesin (polytetrafluoroethylene). The sliding member 5 has the function of reducing friction between the outer member 3 and the jacking device J1, thereby preventing the jacking device J1 from tipping over due to expansion and contraction caused by temperature changes in the bridge girder BG during the bridge bearing replacement work in a jacked-up state.

[0043] (Height adjustment filler) The inner member 2 is bolted directly to the upper surface of the jack-up bracket B2, and the outer member 3 is bolted to the underside of the bridge girder BG, which is the superstructure, i.e., to the lower flange H1 via a height-adjusting filler 4 that corresponds to the gradient of the lower flange H1. As a result, in the jack-up movement limiting device 1, which is a temporary device and not permanent, and can be applied to bridges with different gradients, the inner member 2 and outer member 3 can be installed horizontally in common, regardless of the gradient of the bridge girder BG, improving safety and reducing the cost of the jack-up movement limiting device 1.

[0044] However, the jack-up movement limiting device 1 may also be turned upside down, with the outer member 3 attached to the upper surface of the jack-up bracket B2 and the inner member 2 attached to the underside of the lower flange H1. This is because the jack-up movement limiting device 1 can resist the horizontal force of an earthquake even when turned upside down.

[0045] According to the jack-up movement restriction device 1 of the embodiment of the present invention described above, the outer surrounding portion 31 of the outer member 3 is spaced apart from the jack surrounding portion 21 of the inner member 2 and is formed so as to surround the jack surrounding portion 21. Therefore, when replacing bridge bearings, even if the bridge is jacked up and the bearings are removed, for example, in the event of a level 1 earthquake, the device can resist the horizontal force and restrict the horizontal movement of the superstructure.

[0046] Furthermore, according to the jack-up movement limiting device 1, the jack surrounding portion 21 is provided at a predetermined distance in the vertical direction from the outer plate portion 30 of the outer member 3. Therefore, even in the unlikely event that the jack device J1 falls over due to horizontal force input during an earthquake, the jack surrounding portion 21 and the outer plate portion 30 come into contact with each other, allowing the jack-up movement limiting device 1 to limit vertical downward movement and minimize the falling and tilting of the superstructure.

[0047] Furthermore, according to the jack-up movement limiting device 1, a total of four slits 23 are formed near the center of the jack surrounding portion 21, which allows it to be close to the circular outer diameter of the jack device J1. This reduces the risk of the hydraulic hose of the jack device J1 interfering with the jack-up operation, and allows the jack-up operation to be carried out safely. In addition, since the horizontality of the jack device J1 is ensured, it can withstand the stress input during, for example, a level 1 earthquake.

[0048] Furthermore, according to the jack-up movement restriction device 1, two large slits 33 are formed in the outer surrounding portion 31 of the outer member 3, making it easier to access the top of the jack device J1, improving work efficiency when jacking up the jack device J1.

[0049] In addition, according to the jack-up movement restriction device 1, sliding materials 5 that reduce friction are attached to the inner surface (lower surface) of the outer plate portion 30 and the inside of the outer surrounding portion 31, so that it can respond to temperature expansion and contraction of the upper structure during jack-up.

[0050] Furthermore, according to the jack-up movement restriction device 1, a central reinforcing rib 34 is formed on the outside of the center of the outer surrounding portion 31, and end reinforcing ribs 35 are formed on the outside of the outer surrounding portion 31 near the slits 33, so that it is possible to resist the impact load when the outer surrounding portion 31 and the jack surrounding portion 21 collide due to an earthquake.

[0051] Furthermore, according to the jack-up movement limiting device 1, a height-adjusting filler 4 is interposed between the outer member 3 and the lower flange H1 according to the gradient of the lower flange H1, so the jack-up movement limiting device 1 can be adapted to bridges with various gradients, thereby achieving cost reduction.

[0052] <Bearing replacement method> Next, a bearing replacement method according to an embodiment of the present invention will be described with reference to Figures 1 to 4 and 5. The description will be given by taking as an example a case where bearing renewal work is carried out to replace the existing bearing of the bridge B1 described above with a new bearing using the jack-up movement restriction device 1 described above. Figure 5 is a flowchart showing each work step of the bearing replacement method according to an embodiment of the present invention.

[0053] (Reinforcement material installation process) First, as shown in FIG. 5, in the bearing replacement method according to the embodiment of the present invention, a reinforcing material installation step for reinforcing the bridge girder BG is carried out as necessary as advance preparation.

[0054] Specifically, in this process, reinforcing ribs are joined to the web of the bridge girder BG, which is a steel girder, using high-strength bolts or welding, etc. to reinforce it so that it does not buckle when jacked up by the jack device J1.

[0055] (Bracket installation process) Next, as shown in Figure 5, in the bearing replacement method according to this embodiment, a bracket installation process is carried out to install a temporary bracket next to the substructure of the bridge B1 in order to secure space for installing the jack device J1.

[0056] Specifically, in this process, the aforementioned jack-up bracket B2 is bolted and attached to the side of the pier P1, which is the substructure, using post-installed anchors or the like (see also Figure 1).

[0057] (Movement restriction device installation process) Next, as shown in FIG. 5, in the support replacement method according to this embodiment, a movement limiting device installation process is carried out in which the above-mentioned jack-up movement limiting device 1 is installed on the jack-up bracket B2 installed in the front bracket installation process.

[0058] Specifically, in this step, as shown in Fig. 1, bolts are inserted into the bolt holes 22 of the inner plate portion 20 to bolt the inner member 2 onto the jack-up bracket B2. Then, at a position directly above the inner member 2, bolts are inserted into the bolt holes 32 of the outer plate portion 30 to join the outer member 3 to the bottom flange H1 of the bridge girder BG.

[0059] At this time, as shown in Figure 2, the jack surrounding portion 21 and the outer surrounding portion 31 are fitted together with a predetermined distance between them, and when the superstructure, the bridge girder BG, moves horizontally, the jack surrounding portion 21 and the outer surrounding portion 31 come into contact and fit together, thereby restricting horizontal and vertical movement during an earthquake.

[0060] In addition, as shown in Figure 1, the aforementioned height-adjusting filler 4, which corresponds to the gradient of the lower flange H1 of the bridge girder BG, is interposed between the lower flange H1 and the outer member 3, and the outer member 3 is bolted to the lower flange H1 so that it is horizontal.

[0061] (Jacking up process) Next, as shown in Figure 5, in the bearing replacement method according to this embodiment, the aforementioned jacking device J1 is installed on the jacking movement limiting device 1 installed in the previous jacking movement limiting device installation process, and the structure is jacked up, thereby performing a jacking up process to remove stress on the existing bearing.

[0062] Specifically, as shown in Figure 2, in this process, a jacking device J1 is installed on the inner plate portion 20 of the jack-up movement restriction device 1, at a predetermined position indicated by a dot-dash circle within the jack surrounding portion 21 (see also Figure 1). After that, the jacking device J1 is operated to extend the jack, jacking up and lifting the outer plate portion 30 and bridge girder BG, thereby removing stress on the existing bearing.

[0063] (Existing bearing removal process) Next, as shown in FIG. 5, in the bearing replacement method according to this embodiment, an existing bearing removal step is carried out to remove the existing bearing from which stress has been removed in the previous step.

[0064] Specifically, in this existing bearing removal process, the shoe seat mortar and sole plate that secure the existing bearing to the pier P1 are chipped off, the anchors that were fixed to the pier P1 are cut, and bolts that were connected to the bridge girder BG, etc. are removed, and the existing bearing is removed.

[0065] (New bearing installation process) Next, as shown in FIG. 5, in the bearing replacement method according to this embodiment, a new bearing installation step is carried out to install a new bearing.

[0066] Specifically, a new sole plate and shoe seat mortar are installed, and a new bearing that meets current earthquake resistance standards is installed. In the bearing replacement method according to this embodiment, a new bracket is installed and the new bearing is bolted to the bracket. However, it is also possible to drill holes in the pier P1 to install new anchor bolts and then bolt the new bearing to the anchor bolts.

[0067] (Jacking down process) Next, as shown in Figure 5, in the bearing replacement method according to this embodiment, after the high-strength bolts are fully tightened and any necessary on-site welding is performed, the jacking device J1 is activated to shorten the jack, and a jacking-down process is carried out in which the load of the superstructure is borne by the new bearings installed in the previous process.

[0068] (Movement restriction device removal process) Next, as shown in Figure 5, the bearing replacement method according to this embodiment involves a movement restriction device removal process in which the bolts and other fastening parts of the jack-up movement restriction device 1 installed in the previous movement restriction device installation process are removed. This completes the bearing renewal work of replacing the existing bearings of bridge B1 with new bearings.

[0069] According to the bearing replacement method according to the embodiment of the present invention described above, it is possible to withstand, for example, a Level 1 earthquake even after jacking up using the jack-up movement restriction device 1 and removing the existing bearings. This makes it possible to simultaneously replace adjacent bearings, unlike conventional bearing replacement methods in which adjacent bearings could not be replaced simultaneously and replacement work was carried out in a staggered pattern, i.e., one bearing at a time, for a single bridge. This makes it possible to significantly shorten the construction period for bearing replacement work.

[0070] Furthermore, as described in the Background Art, the bearing replacement method according to this embodiment does not require the installation of time-consuming temporary equipment such as a jack device and a separate temporary support device, unlike conventional bearing replacement methods such as the seismic isolation device replacement method described in Patent Document 2. Therefore, the bearing replacement method according to this embodiment does not require the securing of a large amount of space around the narrow bearing, making it easy to perform the bearing renewal work.

[0071] Although the jack-up movement restriction device 1 and the bearing replacement method using the same according to the embodiment of the present invention have been described in detail above, the above-mentioned and illustrated embodiments are merely examples of specific embodiments for carrying out the present invention, and therefore the technical scope of the present invention should not be interpreted as being limited by these. [Explanation of symbols]

[0072] 1: Movement restriction device for jacking up 2: Inner member 20: Inner plate part 21: Jack enclosure 22: Bolt hole 23: Slit 3:Outer member 30: Outer plate part 31:Outer enclosure 32: Bolt hole 33: Slit 34: Central reinforcing rib (reinforcing rib) 35: End reinforcement rib (reinforcement rib) 4: Height adjustment filler 5:Sliding material B1: Bridge BG: Bridge girder (superstructure) H1: Lower flange (upper structure) P1: Pier (substructure) B2: Jack-up bracket (extension bracket) J1: Jack device

Claims

1. A movement limiting device for jack-up that is installed around a jack that is supported by the substructure of a bridge and lifts the superstructure when replacing bridge bearings, and that limits the movement of the superstructure during an earthquake and is capable of resisting horizontal forces during an earthquake, an inner member supported by one of the upper structure and the lower structure, and an outer member supported by the other, The inner member has a flat inner plate portion and a jack surrounding portion that stands on the inner plate portion and surrounds the jack at a distance from the jack, The outer member has a plate-shaped outer plate portion and an outer surrounding portion that is erected on the outer plate portion and surrounds the jack surrounding portion while being spaced apart from the jack surrounding portion, The jack surrounding portion and the outer surrounding portion are fitted together to limit horizontal movement of the superstructure during an earthquake. A movement limiting device for jacking up, characterized by the above.

2. The jack surrounding portion abuts against the outer plate portion, thereby restricting vertical movement of the superstructure during an earthquake.

2. The jack-up movement limiting device according to claim 1,

3. A slit for inserting a hydraulic hose of the jack is formed in either or both of the jack surrounding portion and the outer surrounding portion.

3. The movement limiting device for jack-up according to claim 1 or 2,

4. A sliding member for reducing friction is attached to the inside of the inner plate portion or the outer plate portion attached to the superstructure.

4. A jack-up movement limiting device according to claim 1, wherein:

5. A reinforcing rib is formed on the outside of the outer surrounding portion.

5. A jack-up movement limiting device according to claim 1, wherein:

6. A height adjusting filler is interposed between the inner plate portion or the outer plate portion attached to the superstructure and the superstructure, the height adjusting filler being in accordance with the gradient of the underside of the superstructure.

6. A jack-up movement limiting device according to claim 1, wherein:

7. A bearing replacement method for replacing an existing bridge bearing with a new bearing, The movement limiting device for jacking up according to any one of claims 1 to 6 is installed, and after jacking up the superstructure of the bridge with a jack and replacing the existing bearings with new bearings, the movement limiting device for jacking up is removed. A bearing replacement method characterized by the above.

8. A temporary jack-up movement limiting device that is installed around a jack that is supported by the substructure of a bridge and lifts the superstructure when replacing the bridge's bearings, limits the movement of the superstructure during an earthquake, and can be removed after the bearings are replaced, an inner member supported by one of the upper structure and the lower structure, and an outer member supported by the other, The inner member has a flat inner plate portion and a jack surrounding portion that stands on the inner plate portion and surrounds the jack at a distance from the jack, The outer member has a plate-shaped outer plate portion and an outer surrounding portion that is erected on the outer plate portion and surrounds the jack surrounding portion while being spaced apart from the jack surrounding portion, The jack surrounding portion and the outer surrounding portion are fitted together to limit horizontal movement of the superstructure during an earthquake. A movement limiting device for jacking up, characterized by the above.

Images