JP2023022886A - Expansion device for bridge using pca member and construction method for the same - Google Patents

Abstract

To improve productivity and ensure quality at construction sites for the new installation and repair of an expansion device for bridges.SOLUTION: An expansion device for bridges attached to a road structure via a PCa pedestal 50 is configured such that the PCa pedestal 50 comprises: a lower pedestal 60 fixed to the road structure; and an upper pedestal 70, detachably attached to the upper part of the lower pedestal 60, on which an expansion device body 10 is placed. The lower pedestal 60 is fixed to the road structure when the expansion device body 10 is replaced. The upper pedestal 70 is removed from the lower pedestal 60 when replacing the expansion device body 10. The lower pedestal 60 and the upper pedestal 70 can be configured to be attached and detached by a one-pass type joint 40.SELECTED DRAWING: Figure 10

Description

TECHNICAL FIELD The present invention relates to a bridge expansion device and a construction method thereof. More specifically, a PCa member is used in which a separate PCa pedestal is used and the bridge expansion device is installed on the PCa pedestal. The present invention relates to a bridge expansion device and its construction method.

Expansion devices for bridges are subject to wear and damage due to vehicle traffic, so they must be replaced and repaired in a timely manner. 2. Description of the Related Art Conventionally, when a bridge expansion joint is replaced or repaired, the removal work of the bridge expansion joint requires manual chipping using a breaker or the like. In this chipping work, noise is generated by the breaker. In addition, the boundary between the portion to be removed and the substructure tends to become unclear, which may cause unnecessary damage to the substructure and affect the soundness of the bridge. In addition, in order to fix the bridge expansion joint to the floor slab, substructure, etc., many fixing anchors are provided on the floor slab and used to fix the bridge expansion joint. Since it is necessary to cut the anchors, etc., the work becomes complicated.

Conventionally, there have been proposed various techniques for easily attaching a bridge expansion device (see, for example, Patent Documents 1 and 2). The technology described in Patent Literature 1 relates to a bridge expansion device that simplifies the installation work so that it can be completed in a short period of time. In this bridge expansion/contraction device, fixing portions are previously protruded at the end portions of the respective opposing bridges. Then, the bridge expansion device is placed on the upper surface of the fixing portion, and the fixing bolts that are vertically inserted through the mounting holes of the mounting portions at both ends of the bridge expansion device and the through holes of the fixing portion are screwed into the fixing nuts to form the bridge. The expansion and contraction device is fastened and fixed to the fixing portion.

In the technique described in Patent Document 1, the bridge expansion device can be attached by placing the bridge expansion device on the fixing portions projecting from the opposite ends of the bridge and fixing the device with fastening means. Therefore, it is possible to simplify the work by eliminating the need for reinforcing reinforcing bar arrangement work, welding work, and post-cast concrete placement work.

The technology described in Patent Document 2 relates to a block-type embedded joint expansion and contraction device for bridges that can be easily assembled, newly installed, and re-repaired using members manufactured at a factory or the like other than the site. is. In this bridge block-type embedded joint expansion/contraction device, a plurality of embedded joints divided in the chipping range of RC floor slabs are placed over the entire roadway. A groove of a predetermined size is set on the rear surface (rear surface) of the block type embedded joint at a predetermined width length in the longitudinal direction. By setting a thin plate-like adjusting metal fitting in this groove, the bridge expansion device is installed.

According to the bridge block-type embedded joint expansion and contraction device described in Patent Document 2, it is easy to transport to the site, the number of man-hours in installation work is reduced, and repair work and new construction work can be performed in a short period of time. there is

Japanese Patent Application Laid-Open No. 2007-315090 JP 2017-40052 A

As described above, in the conventional technology, when removing an existing bridge expansion/contraction device, chipping work using a breaker or the like causes unnecessary damage to the existing floor slabs, substructures, and the like. In addition, since noise is generated during the removal work of the bridge expansion joints, it is necessary to devise measures to reduce the noise. In addition, a large number of fixing anchors are required to fix the bridge expansion/contraction device to the floor slab or the like, which complicates not only the removal work but also the installation work. In addition, regardless of repair or new construction, manual construction is the majority, and the construction quality and durability generally depend on the work quality at the time of construction. Furthermore, the current situation is that it is difficult to secure workers because skilled workers are aging.

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above-mentioned circumstances. The purpose is to provide a method.

In order to achieve the above-described objects, the expansion device for a bridge using the Pca member and the construction method thereof according to the present invention have the following features.

TECHNICAL FIELD The present invention relates to a bridge expansion device and a construction method thereof, which is attached to a road structure (for example, a floor slab) via a PCa pedestal, and a construction method thereof. This PCa pedestal consists of a lower pedestal fixed to the road structure, and an upper pedestal detachably attached to the upper part of the lower pedestal and on which the expansion device main body is placed.

The lower pedestal is fixed to the road structure when the expansion device main body is replaced, and the upper pedestal is removed from the lower pedestal when the expansion device main body is replaced. That is, when the expansion device body is attached to the road structure, the lower pedestal is fixed to the road structure, the upper pedestal is attached to the upper part of the lower pedestal, and the expansion device main body is attached to the upper part of the upper pedestal. When replacing the expansion device main body, the expansion device main body is replaced by removing the upper pedestal attached to the upper part of the lower pedestal and the expansion device main body while the lower pedestal is fixed to the road structure.

Further, in the bridge expansion device and the construction method thereof having the configuration described above, it is possible to provide a one-pass joint for attaching and detaching the upper pedestal to and from the lower pedestal. That is, the lower pedestal and the upper pedestal can be attached and detached by a one-pass joint.

In the bridge expansion joint using the Pca member and the construction method thereof according to the present invention, the main body of the expansion joint is installed on a road structure such as a floor slab by using the upper and lower divided PCa pedestals. Then, when replacing the expansion device main body, only the upper pedestal and the expansion device main body installed thereon are removed while the lower pedestal remains fixed to the road structure such as the floor slab. Also, the lower pedestal and the upper pedestal can be attached and detached by a one-pass joint.

Therefore, if the bridge expansion joint using the Pca member according to the present invention is installed, in the repair work of the main body of the expansion joint, chipping work becomes unnecessary or only a very small part, and the generation of noise can be reduced. In addition, the influence on road structures such as floor slabs is extremely small. In addition, construction work and repair/replacement work for bridge expansion devices become easier, and there is a possibility that construction costs can be reduced, and construction quality can be improved.

As described above, according to the bridge expansion joint using the Pca member and the construction method thereof according to the present invention, it is possible to improve the productivity and ensure the quality of the construction site in the installation and repair of the bridge expansion joint.

FIG. 2 is a schematic diagram of a lower pedestal used in the bridge expansion/contraction device according to the embodiment of the present invention. The schematic diagram of the upper base used for the expansion-contraction apparatus for bridges which concerns on embodiment of this invention. 1 is a schematic diagram of a one-pass joint used in a bridge expansion device according to an embodiment of the present invention; FIG. FIG. 2 is a schematic diagram showing an installation procedure of the bridge expansion/contraction device according to the embodiment of the present invention. FIG. 2 is a schematic diagram showing an installation procedure of the bridge expansion/contraction device according to the embodiment of the present invention. FIG. 2 is a schematic diagram showing an installation procedure of the bridge expansion/contraction device according to the embodiment of the present invention. FIG. 2 is a schematic diagram showing an installation procedure of the bridge expansion/contraction device according to the embodiment of the present invention. FIG. 2 is a schematic diagram showing an installation procedure of the bridge expansion/contraction device according to the embodiment of the present invention. FIG. 2 is a schematic diagram showing an installation procedure of the bridge expansion/contraction device according to the embodiment of the present invention. FIG. 2 is a schematic diagram showing an installation procedure of the bridge expansion/contraction device according to the embodiment of the present invention. FIG. 2 is a schematic diagram showing an installation procedure of the bridge expansion/contraction device according to the embodiment of the present invention. The schematic diagram which shows the waterproofing mechanism installed in the lower base of the expansion-contraction apparatus for bridges which concerns on embodiment of this invention.

Hereinafter, a bridge expansion device and a construction method thereof according to an embodiment of the present invention will be described with reference to the drawings. 1 to 12 illustrate a bridge expansion device according to an embodiment of the present invention and a construction method thereof, and FIG. ), Figure 2 is a schematic diagram of the upper pedestal (a: plan view, b: vertical cross-sectional view, c: side view), Figure 3 is a schematic diagram of the one-pass joint, and Figures 4 to 11 are the installation procedure for the bridge expansion device. , and FIG. 12 is a schematic diagram (a: perspective view, b: enlarged vertical cross-sectional view) showing the waterproof mechanism of the lower pedestal.

<Summary of expansion joint for bridges and its construction method>
In the construction work of the expansion joint for bridges, the present invention provides a pedestal (hereinafter referred to as PCa conversion) for installing the expansion joint main body instead of directly installing the expansion joint main body on the floor slab or road structure by the conventional construction method. (referred to as a pedestal) is fixed to a structure such as a floor slab, and then the main body of the expansion device is installed on the PCa pedestal. This construction method is particularly useful in the replacement work of the main body of the expansion device, but it can also be applied when installing the main body of the expansion device.

In addition, the PCa pedestal is separated so that it can be removed easily, quickly, and reliably even by an unskilled worker while reducing noise when exchanging the expansion device main body ( It has a structure divided into upper and lower parts, and is composed of a lower pedestal and an upper pedestal.

Also, the upper pedestal is detachably attached to the lower pedestal. The mechanism for attaching and detaching the lower pedestal and the upper pedestal uses a one-pass type joint used for segments for shield tunnels to reduce noise when exchanging the expansion device body and to allow easy attachment and detachment. . Furthermore, by manufacturing the upper pedestal and the expansion device main body as an integral structure at the factory, construction can be performed more easily and quickly, and there is a possibility that construction costs can be reduced.

<Expansion device body>
The expansion device main body 10 is a device for following the expansion and contraction of the bridge girders so as not to restrain the temperature expansion and contraction of the bridge girders in the bridge and contraction due to creep, and not to impair the running performance of automobiles passing through the bridge. The expansion device main body 10 in the present embodiment is a device having a general structure that has been used conventionally, and as shown in FIG. It has a pair of foundations 11 placed with each other. A main body portion 12 of the expansion device main body 10 is installed so as to span between the pair of base portions 11 . Further, each base portion 11 is fixed to the floor slab 20 by embedding the lower ends (anchor bars) of the reinforcing bars 63 arranged inside each base portion 11 in the floor slab 20 . A waterproof mechanism 30 is provided between the pair of base portions 11 . The expansion device body 10 is not limited to the structure shown in FIG. 1, and may have any structure as long as it can be attached to the upper base 70.

<PCa pedestal>
The present invention is characterized by a PCa (Precast Concrete) pedestal for installing the expansion device main body 10 . The PCa pedestal 50 of this embodiment is a member manufactured in advance at a factory, and consists of a lower pedestal 60 and an upper pedestal 70 detachably attached to the lower pedestal 60 . In this embodiment, the one-pass joint 40 is used for attaching and detaching the lower seat 60 and the upper seat 70 . As will be described in detail later, the lower pedestal 60 is a member having a function of fixing to the floor slab 20 and may be integrated with the floor slab 20 in some cases. Further, the upper pedestal 70 is a member on which the expansion device main body 10 is attached and which is detachable from the lower pedestal 60 , and may be integrated with the expansion device main body 10 .

<Lower pedestal>
As shown in FIG. 1, the lower pedestal 60 includes a pair of lower pedestal main bodies 61 that are divided into two in the extending direction of the road (traveling direction of the vehicle). Each lower pedestal main body 61 is provided with end steel plates 62 on sides facing each other, a plurality of reinforcing bars 63 are arranged inside, and concrete 64 is placed in a grid pattern. In addition, the female member 41 of the one-pass joint 40 is attached via a fixed reinforcing bar 65 in a space surrounded by concrete 64 placed in a grid pattern.

In the example shown in FIG. 1, the installation position of the female member 41 is determined when the lower pedestal 60 is manufactured. That is, when the lower pedestal 60 is manufactured in a factory, the female member 41 can be installed at an appropriate position within a predetermined range at the site where the lower pedestal 60 is installed without fixing the installation position of the female member 41 . It is preferable to keep As a result, the female member 41 can be installed according to the bar arrangement of the floor slab 20 and the like, and the lower pedestal 60 can be easily installed without damaging the reinforcing bars (not shown) of the floor slab 20 and the like. can do. In the case of such a structure, it is necessary to set the installation position of the male member 42 in accordance with the installation position of the female member 41 also in the upper pedestal 70 .

The lower pedestal 60 is fixed to the floor slab 20 using a plurality of anchors 67 . For example, after installing the lower pedestal 60 on the floor slab 20 , the anchors 67 are welded to the reinforcing bars 63 of the lower pedestal 60 . Then, the lower pedestal 60 is fixed to the floor slab 20 by pouring concrete into the gaps of the lower pedestal 60 or filling the gaps of the lower pedestal 60 with mortar (non-shrinkage type) (Fig. 6, See Figure 7). Further, in this embodiment, the lower pedestal 60 having a structure fixed to the floor slab 20 is shown, but the lower pedestal 60 and the floor slab 20 may be integrally made of PCa. That is, the floor slab 20 made of PCa and the lower pedestal 60 made of PCa integrally with the floor slab 20 can function as the lower pedestal 60 defined in the present invention.

<Waterproof Mechanism>
As shown in FIG. 12, the lower pedestal 60 is preferably provided with a waterproof mechanism 30 for waterproofing between the pair of lower pedestal main bodies 61 . The water stop material 32 spanning between the pair of lower pedestal bodies 61 has a fixed portion 36 and a free portion 37 having a substantially U-shaped cross section. This water stop material 32 can stop water between the pair of lower pedestal main bodies 61 .

The lower pedestal 60a to which the waterproof mechanism 30 is attached has substantially the same structure as the lower pedestal 60 shown in FIG. The lower pedestal 60a to which the waterproof mechanism 30 is attached is provided with a notch 66 at the upper part on the side facing each other. A steel plate 62a is attached. A nut (cap nut) 31 is embedded in the lower surface of the end steel plate 62a attached to the notch 66. As shown in FIG.

Then, the fixing portion 36, which is one end portion of the water stop material 32, is placed on the upper surface of one end steel plate 62a, and the bearing pressure plate 33 is made to face the notch portion 66 from the upper portion of the fixing portion 36. The water stop material 32 (fixed portion 36) is fixed. A plurality of bolt insertion holes 34 are provided along the length direction of the bearing plate 33 , and a plurality of nuts (cap nuts) 31 are embedded in the lower base body 61 so as to face the bolt insertion holes 34 .

Similarly, the fixed portion 36, which is the other end portion of the water stop material 32, is placed on the upper surface of the other end steel plate 62a, and the bearing pressure plate 33 is made to face the cutout portion 66 from the upper portion of the fixed portion 36 to support. The water stop material 32 ( The fixing part 36) is fixed. In addition, since the water stop material 32 has the free portion 37, it follows the movement of the expansion device main body 10 and does not restrict temperature expansion and contraction of the bridge girder and contraction due to creep.

The water stop material 32 is made of rubber, SUS, or the like, and is installed in consideration of drainage treatment, terminal treatment, and the like. The water stop material 32 is a member that is left on the floor slab 20 when the lower pedestal 60 is fixed to the floor slab 20 and the extension device main body 10 is replaced, but there is a risk of deterioration over time. Therefore, when exchanging the expansion device body 10 and the upper pedestal 70, it is preferable to replace the waterproof mechanism 30 made of the waterproof material 32 or the like while the pair of lower pedestal bodies 61 are fixed to the floor slab 20. .

<Upper pedestal>
As shown in FIG. 2, the upper pedestal 70 includes a pair of upper pedestal main bodies 71 that are divided into two parts in the extending direction of the road (traveling direction of the vehicle). Each upper pedestal main body 71 has a plurality of reinforcing bars 72 arranged therein and concrete 73 placed therein. A male member 42 of the one-pass joint 40 is attached via a fixed reinforcing bar 74 at a position corresponding to the female member 41 installed on the lower pedestal 60 .

In the example shown in FIG. 2, the installation position of the male member 42 is determined when the upper pedestal 70 is manufactured. As described above, when the lower pedestal 60 is manufactured at the factory, the female member 41 is placed at an appropriate position within a predetermined range at the site where the PCa pedestal 50 is installed without fixing the installation position of the female member 41. You can leave it ready to install. In the case of such a structure, it is necessary to set the installation position of the male member 42 in accordance with the installation position of the female member 41 also in the upper pedestal 70 .

In this embodiment, after the lower pedestal 60 and the upper pedestal 70 are integrated, the expansion device main body 10 is attached to the upper part of the upper pedestal 70. may be changed. That is, the upper pedestal 70 made of PCa and the expansion device main body 10 made of PCa integrally with the upper pedestal 70 can function as the upper pedestal 70 defined in the present invention.

<One-pass joint>
The one-pass joint 40 is an example of a mechanism for detachably connecting the lower pedestal 60 and the upper pedestal 70 . The one-pass joint 40 is a joint for detachably connecting the lower seat 60 and the upper seat 70, and is sometimes called a quick joint. This one-pass joint 40 consists of a female member 41 and a male member 42, as shown in FIGS. 3 and 6-11. The female member 41 has a recess 43 into which the distal end portion (fixing bolt 44) of the male member 42 is pushed.

A female threaded portion 46 is provided in the concave portion 43 of the female member 41 for screwing a male threaded portion 45 provided on the outer peripheral surface of a fixing bolt 44 that constitutes the male member 42 . Also, although not shown, it is positioned closer to the open end side of the recess 43 than the female threaded portion 46, and is movable in the axial direction within the recessed portion 43, allowing the male threaded portion 45 to be pushed thereinto. A fixing member (not shown) is provided for preventing the male screw portion 45 from being pulled out from the recess 43 by coming into close contact with the male screw portion 45 after it is pushed in.

On the other hand, the male member 42 has a fixing bolt 44 to be inserted into the recess 43 of the female member 41 and an anchor portion 47 to be fixed to the upper pedestal 70 . In this embodiment, the anchor portion 47 has a sheath tube 47a through which the fixing bolt 44 is inserted, and a flange portion 47b protruding from the lower end of the sheath tube 47a toward the outer periphery. A male threaded portion 45 is provided at the tip of the fixing bolt 44 for screwing into a female threaded portion 46 provided in the concave portion 43 of the female member 41 . The male threaded portion 45 may be provided over the entire length of the fixing bolt 44. In this case, a female threaded portion (not shown) may be provided on the inner wall surface of the sheath tube 47a.

In this embodiment, the female member 41 is attached to the lower pedestal 60 and the male member 42 is attached to the upper pedestal 70 . Then, the upper pedestal 70 is placed above the lower pedestal 60, and the tip of the fixing bolt 44 of the male member 42 is pushed into the fixing member provided in the recess 43 of the female member 41, and further into the recess 43 of the female member 41. By screwing the male threaded portion 45 of the fixing bolt 44 to the provided female threaded portion 46 , the lower pedestal 60 and the upper pedestal 70 can be connected and fixed using the one-pass joint 40 .

Further, by turning the fixing bolt 44 of the male member 42 in the disconnecting direction, the fixing bolt 44 is removed from the female threaded portion 46 provided in the concave portion 43 of the female member 41 and the fixing member (not shown), thereby forming a one-pass joint. 40, the connection state between the lower pedestal 60 and the upper pedestal 70 can be released.

In this embodiment, a one-pass joint 40 is used to detachably fix the lower pedestal 60 and the upper pedestal 70 . The structure of the one-pass joint 40 is not limited to the one described above, and the upper pedestal 70 can be fixed to the lower pedestal 60 to be integrated, and the fixing of the lower pedestal 60 and the upper pedestal 70 can be released to separate them. Any structure is possible as long as it is possible. Furthermore, the mechanism for detachably fixing the lower pedestal 60 and the upper pedestal 70 is not limited to the one-pass type joint 40. Any mechanism may be used as long as it can release the fixation of 70 and separate the two.

<Installation procedure for expansion joints for bridges>
A construction method of a bridge expansion device using a Pca member according to an embodiment of the present invention will be described with reference to FIGS. FIG. 4 is an explanatory diagram showing the state in which the existing bridge expansion device is installed, FIG. 5 is an explanatory diagram showing the state in which the existing bridge expansion device is removed, and FIG. FIG. 7 is an explanatory diagram showing a state in which the filling (filling) process is performed after installing the lower pedestal 60, FIG. 8 is an explanatory diagram showing the process of installing the upper pedestal 70, and FIGS. FIG. 11 is an explanatory diagram showing the process of installing the expansion joint body 10, and FIG. 11 is an explanatory diagram showing the process of removing the expansion joint body 10 and the upper pedestal 70. FIG. In the following description, the object to which the PCa-ized pedestal 50 is fixed is the floor slab 20, but depending on the structure of the bridge, the PCa-ized pedestal 50 may be fixed to another road structure instead of the floor slab 20. good too.

In the construction procedure of the bridge expansion joint described below, the case where there is an existing bridge expansion joint is also explained. In this regard, the construction method of the bridge expansion joint of the present invention causes unnecessary damage to the existing floor slab 20 and substructures due to chipping work using a breaker or the like when removing the existing bridge expansion joint. It is intended to reduce the noise generated during the removal work of the expansion joints for bridges.

However, if there is an existing bridge expansion/contraction device, the bridge expansion/contraction device using the Pca member according to the embodiment of the present invention cannot be installed unless this bridge expansion/contraction device is removed. After installing the bridge expansion device using the Pca member according to the embodiment of the present invention, the above-described object of the present invention can be achieved. Therefore, the case where there is an existing bridge expansion joint is also explained. This is a necessary step for the process, and does not go against the object of the present invention.

<Construction procedure/when existing bridge expansion joints exist>
As shown in FIG. 4, if there is an existing bridge expansion/contraction device, it is necessary to remove this bridge expansion/contraction device. Therefore, the existing bridge expansion joints are removed by chipping work using a breaker or the like. The chipping work is work for securing a space for installing the PCa base 50 and the new expansion device body 10 . When the chiseling work is completed, as shown in FIG. 5, the anchor bar (reinforcing bar 13) for fixing the existing bridge expansion device to the floor slab 20 remains on the floor slab 20 below.

In this state, as shown in FIG. 6, the lower pedestal 60 is installed in the lower part of the space formed by the chiseling work, and the lower pedestal 60 is connected to the floor slab 20 using anchors 67 . Subsequently, as shown in FIG. 7, a filling (filling) step is performed, and as shown in FIG. The lower pedestal 60 and the upper pedestal 70 are integrated and fixed by the female member 41 provided on the upper pedestal 70 and the male member 42 provided on the upper pedestal 70 . 7 and 8, reference numeral 68 denotes a filling material (concrete or mortar).

After that, as shown in FIG. 9 , the new expansion/contraction device main body 10 is installed on the upper pedestal 70 with the new expansion/contraction device main body 10 facing from above the upper pedestal 70 . Then, as shown in FIG. 10, post-cast concrete 80 is placed in the space in which the upper pedestal 70 and the new expansion device main body 10 are installed, and the installation of the new expansion device main body 10 is completed.

<Installation procedure/When PCa pedestal (lower pedestal) is installed>
As shown in FIG. 10, when the bridge expansion device using the Pca member according to the embodiment of the present invention is already installed, as shown in FIG. and the female member 41 of the one-pass joint 40 provided on the lower seat 60 are released. By turning the fixing bolt 44 of the male member 42 in the disconnecting direction, the fixing bolt 44 is removed from the female threaded portion 46 and the fastening portion provided in the concave portion 43 of the female member 41, and the lower pedestal 60 and the upper portion by the one-pass type joint 40 are separated. The connected state of the pedestal 70 can be released. When the extension device main body 10 and the upper pedestal 70 are removed, the lower pedestal 60 fixed to the floor slab 20 remains as shown in FIG.

From this state, as shown in FIG. 8, the lower pedestal 60 and the upper pedestal 70 are integrated and fixed by the one-pass type joint 40 . Then, as shown in FIG. 9 , the new expansion device main body 10 is installed on the upper pedestal 70 with the new expansion device main body 10 facing from above the upper pedestal 70 . Further, as shown in FIG. 10, post-cast concrete 80 is placed in the space in which the upper pedestal 70 and the new expansion device main body 10 are installed, and the installation of the new expansion device main body 10 is completed.

<Installation procedure/when installing a new PCa pedestal>
When installing a new bridge expansion device using the Pca member according to the embodiment of the present invention during bridge construction, as shown in FIG. Keep 5 to 11 show the state in which the existing bridge expansion and contraction device has been removed, so there are anchor bars (reinforcing bars 13). The reinforcing bars 13) are not present.

Subsequently, in the same manner as in the existing bridge expansion and contraction device, as shown in FIG. 7, a filling (filling) step is performed, and as shown in FIG. The lower pedestal 60 and the upper pedestal 70 are integrated and fixed by the member 41 and the male member 42 provided on the upper pedestal 70 . When installing a new bridge expansion and contraction device according to the present embodiment, in addition to using the illustrated anchor 67, pre-attached anchors (floor slab embedded anchors) such as anchor bars are embedded in the floor slab 20. You can Furthermore, by integrally providing an anchor portion (not shown) in the lower portion of the female member 41 of the one-pass joint 40 , the anchor portion may be used as an auxiliary element of the anchor 67 .

After that, as shown in FIG. 9, the new expansion/contraction device main body 10 is faced from above the upper pedestal 70, and the new expansion/contraction device main body 10 is installed on the upper pedestal 70. As shown in FIG. and the new expansion joint main body 10 are installed, post-cast concrete 80 is placed in the space, and the installation of the new expansion joint main body 10 is completed.

<Other embodiments>
In the above explanation of the construction procedure, the case of using the PCa pedestal 50 composed of the lower pedestal 60 and the upper pedestal 70 shown in FIGS. 1 and 2 has been explained. As described above, the member that detachably connects the lower pedestal 60 and the upper pedestal 70 is not limited to the one-pass joint 40 . Moreover, when the one-pass joint 40 is used, the installation positions of the female member 41 and the male member 42 can be adjusted. Also, the waterproof mechanism 30 can be provided on the lower pedestal 60 . Further, the floor slab 20 and the lower pedestal 60 may be integrally made of PCa, or the upper pedestal 70 and the extension device main body 10 may be integrally made of PCa.

When using the PCa pedestal 50 having such a structure, the construction procedure is appropriately changed according to the construction procedure described above, and the Pca member is used for the road structure (floor slab 20). Bridge expansion joints can be installed or removed.

REFERENCE SIGNS LIST 10 main body of expansion device 11 base 12 main body 13 reinforcing bar of main body of expansion device 20 floor slab 30 waterproof mechanism 31 nut 32 water stop material 33 bearing plate 34 bolt insertion hole 35 bolt 36 fixed portion 37 free portion 40 one-pass joint 41 female member 42 Male member 43 Recess 44 Fixing bolt 45 Male threaded portion 46 Female threaded portion 47 Anchor portion of male member 47a Sheath tube 47b Flange portion 50 PCa base 60 Lower base 60a Lower base for attaching waterproof mechanism 61 Lower base main body 62 End steel plate 62a End steel plate for installing waterproof mechanism 63 Reinforcing bar of lower pedestal 64 Concrete 65 Fixed reinforcing bar 66 Notch 67 Anchor 68 Filling material 70 Upper pedestal 71 Upper pedestal main body 72 Reinforcing bar of upper pedestal 73 Concrete 74 Fixed reinforcing bar 80 Post-cast concrete

Claims (4)

A bridge expansion device attached to a road structure via a PCa pedestal,
The PCa pedestal consists of a lower pedestal fixed to the road structure, and an upper pedestal detachably attached to the upper part of the lower pedestal and on which the expansion device main body is placed,
The lower pedestal is fixed to the road structure when the expansion device main body is replaced,
The upper pedestal is removed from the lower pedestal when exchanging the expansion device main body,
An expansion device for a bridge using a Pca member characterized by: A one-pass joint for attaching and detaching the upper pedestal to and from the lower pedestal,
An expansion device for a bridge using the Pca member according to claim 1, characterized in that: A construction method for a bridge expansion device attached to a road structure via a PCa pedestal,
The PCa pedestal consists of a lower pedestal fixed to the road structure, and an upper pedestal detachably attached to the upper part of the lower pedestal and on which the expansion device main body is placed,
When the expansion device main body is attached to the road structure, the lower pedestal is fixed to the road structure, the upper pedestal is attached to the upper part of the lower pedestal, and the expansion device main body is attached to the upper part of the upper pedestal,
When replacing the expansion device main body, the expansion device main body is replaced by removing the upper pedestal attached to the upper part of the lower pedestal and the expansion device main body while the lower pedestal is fixed to the road structure.
A construction method for a bridge expansion device using a Pca member, characterized by: The lower pedestal and the upper pedestal are attached and detached by a one-pass joint,
A construction method for a bridge expansion device using the Pca member according to claim 3, characterized in that:

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