JP2021031928A - Permanent scaffolding installation method and bridge accessory installation method - Google Patents

Abstract

To provide a permanent scaffolding installation method and a bridge accessory installation method that enable the shortening of a construction period for installing a permanent scaffold or a bridge accessory in a place having a construction limit.SOLUTION: An installation method for installing a permanent scaffolding under a bridge includes the steps of: installing a skeleton 20 of a permanent scaffolding 11 at a first height outside a construction limit 10 with a suspension member 21 connecting arm members 7, 6a, 6b and 4b of bridge girders 2a to 2c and the skeleton 20; and lowering the skeleton 20 from the first height outside the construction limit 10 to a second height with a chain block and installing the skeleton 20 at the second height with the suspension member 21. The skeleton 20 is lowered from the first height to the second height while aligned with respect to the girders 2a to 2c by the suspension member 21.SELECTED DRAWING: Figure 1

Description

The present invention relates to a method of installing a permanent scaffold of a permanent scaffold installed under a bridge and a method of installing a bridge accessory of an accessory installed under the bridge.

In bridges such as viaducts on roads and railways, permanent scaffolding may be installed under the existing bridges (see Patent Document 1). For example, on roads, intersections, railroads, rivers, etc., it is difficult to install temporary scaffolding for inspection and repair necessary for bridge maintenance. In such a place, by providing a permanent scaffolding, the subsequent maintenance of the bridge can be carried out appropriately and efficiently.

To install the permanent scaffolding, a method is adopted in which a temporary scaffolding is installed under the existing bridge and the permanent scaffolding is installed in the temporary scaffolding. However, there are building limits under bridges such as on intersections, on railroads, and on rivers. Therefore, it is necessary to provide the temporary scaffolding outside the building limit, that is, above the building limit, and the height of the temporary scaffolding is limited. In such a temporary scaffold, it is not possible to install a permanent scaffold that secures a sufficient space under the girder necessary for the maintenance of the bridge. Therefore, in such places, by restricting traffic on roads and using mechanical scaffolding such as aerial work platforms, it is necessary to install permanent scaffolding that secures sufficient space under the girder necessary for maintenance of bridges. There are many.

JP-A-2019-2218

However, when traffic is restricted on roads, it takes time to discuss construction coordination with related organizations related to construction, and the working time is limited to nighttime when traffic is light. In addition to permanent scaffolding, bridge accessories such as inspection roads, drainage devices, and attachments may be installed under the bridge, and similar problems occur in the case of installation work of such accessories. I have something to do.

The present invention has been made to solve the above problems, and an object of the present invention is a method for installing a permanent scaffold that enables shortening of the construction period for installing a permanent scaffold or a bridge accessory in a place where a building limit exists. And to provide a method of installing bridge accessories.

The permanent scaffolding installation method for solving the above problems is an installation method in which a permanent scaffolding is installed under a bridge, and the framework of the permanent scaffolding is connected to the support portion of the girder and the framework outside the building limit. In the process of installing the skeleton at the first height with the hanging material, and outside the building limit, the skeleton is lowered from the first height to the second height by the hanging device, and the skeleton is lowered with the hanging material to the second. The scaffold is lowered from the first height to the second height in a state where the skeleton is aligned with the girder by the suspending material, which comprises a step of installing at a height.

According to the above configuration, the skeleton is assembled at the first height and then lowered to the second height before the scaffolding panel is installed. As a result, it is possible to shorten the construction period for installing a permanent scaffold with a space under the girder in a place where the height of the temporary scaffold is limited by the construction limit.

In the above-mentioned permanent scaffolding installation method, the skeleton is installed at the first height in the temporary scaffolding installed outside the building limit under the bridge, and after the temporary scaffolding is dismantled, the skeleton is the first. It may be configured to be lowered to two heights.

According to the above configuration, even in a place where the height of the temporary scaffold is limited by the building limit, the temporary scaffold is installed outside the building limit, and after the temporary scaffold is dismantled, the skeleton is changed from the first height to the second. By lowering it to a height, it is possible to install a permanent scaffolding that secures sufficient space under the girder.

In the above-mentioned permanent scaffolding installation method, the suspending material includes at least an adjusting hole, a lower fixing hole located below the adjusting hole, and an upper fixing hole located above the adjusting hole. The hole is composed of an elongated hole extending in the hanging direction of the skeleton, the lower fixing hole and the upper fixing hole are formed of a round hole, and when the skeleton is at the first height, the suspending material is When the frame is lowered from the first height to the second height by being fixed to the support portion at the lower end of the lower fixing hole and the adjusting hole, the lower fixing hole is used. The fixing is released, then the fixing member located at the lower end of the adjustment hole is loosened, and the suspending material is attached to the support so that the fixing member acts as a guide member and moves to the upper end of the adjustment hole. The suspending material may be lowered with respect to the support portion and fixed to the support portion at the upper end portions of the upper fixing hole and the adjusting hole. According to the above configuration, when the skeleton is lowered from the first height to the second height, the suspension member can make the fixing member engaged with the adjusting hole function as a guide member.

In the above-mentioned permanent scaffolding installation method, when the skeleton is lowered from the first height to the second height, a plurality of guide members may be engaged with the adjusting hole. According to the above configuration, since a plurality of guide members are engaged with the adjusting hole, the posture when the skeleton is lowered can be stabilized.

In the method for installing a permanent scaffold, the framework includes a vertical beam extending in the direction of the bridge axis and a cross beam extending in the direction perpendicular to the bridge axis, one of which is an upper beam located on the upper side and the other of the upper beam. A lower beam located on the lower side, the suspension member is connected to one of the upper beam and the lower beam, and the suspension device includes the support portion and the one beam member. The suspension position of the one beam member by the suspension device may be displaced in the direction in which the one beam member extends with respect to the suspension member.

According to the above configuration, the skeleton can be suspended near the suspending material. Therefore, even if the descent speed of the suspension device varies, the inclination of the skeleton can be made smaller than when the suspension position is separated from the suspension material. Further, the suspension device may be arranged between the support portion and the beam material of any of the upper beam and the lower beam.

In the method for installing a permanent scaffold, for example, the upper beam is the vertical beam, the lower beam is the horizontal beam, the suspending material is connected to the support portion and the vertical beam, and the suspending device is formed. It is arranged between the support portion and the vertical beam, and the suspension position of the upper beam by the suspension device is configured to be deviated in the direction in which the vertical beam extends with respect to the suspension material. According to the above configuration, the skeleton can be suspended by the suspension device at a position deviated from the suspension material in the direction in which the vertical beam extends.

In the method of installing a permanent scaffold, the framework includes at least one of a vertical beam extending in the bridge axis direction and a cross beam extending in the direction perpendicular to the bridge axis, and the suspending material is connected to the beam material and the suspension is provided. The lower device is arranged between the support portion and the beam material, and the suspension position of the beam material by the suspension device is configured to be displaced in the direction in which the beam material extends with respect to the suspension material. May be good.

According to the above configuration, the skeleton can be suspended by the suspending device at a position deviated from the suspending member in the extending direction of the beam member. The skeleton may be only a beam material of either a vertical beam or a horizontal beam. For example, in the case of only a vertical beam, a temporary material may be used instead of the horizontal beam.

The bridge accessory installation method for solving the above problems is an installation method in which an accessory is installed under the bridge, and the accessory is connected to the support portion of the girder and the accessory outside the building limit. The step of installing the accessory at the first height with the hanging material, the step of suspending the accessory with the hanging device, and the step of suspending the accessory from the first height to the second height outside the building limit. The first height is provided with a step of descending at and installing the accessory at the second height with the hanging material, and the accessory is aligned with the girder by the hanging material. Is descended to the second height. According to the above configuration, the appendages are lowered from the first height to the second height. Therefore, even in a place where the height of the temporary scaffolding is limited by the construction limit, the construction period can be shortened.

According to the present invention, it is possible to shorten the construction period for installing a permanent scaffold or a bridge accessory in a place where a building limit exists.

Cross-sectional view of the upper and lower bridges. Top view of the upper layer. (A) and (b) are perspective views of the main part showing the support structure of the skeleton, (a) shows the girder portion inside the ring, and (b) is the central girder portion in the direction perpendicular to the bridge axis. Is shown. (A) is a side view of the hanging material, (b) to (d) are views showing the positional relationship between the arm material and the hanging material, and (b) shows the support holes of the arm material. c) shows the state of the hanging material supporting the skeleton at the first height, and (d) shows the state of the hanging material supporting the skeleton at the second height. (A) is a front view showing a state in which the skeleton is suspended by a chain block, and (b) is a front view of the chain block. (A) is a diagram showing a state in which the temporary scaffold is installed in the upper layer, and (b) is a diagram showing a state in which the skeleton is supported at the first height. The figure which shows the state which the skeleton is descending. The figure which shows the middle of descending the skeleton from the 1st height to the 2nd height. The figure which shows the state which lowered the skeleton to the 2nd height. The figure which shows the state which the side panel is attached. The figure which shows the state which the scaffolding panel which constitutes a permanent scaffolding is attached. (A) to (e) are diagrams showing a support structure of a hanging material when there are two support holes. (A) to (e) are views showing a modified example in which two fixing holes for a hanging material are provided above and below the adjusting hole.

Hereinafter, a method of installing a permanent scaffold to which the present invention has been applied will be described with reference to the drawings.
As shown in FIGS. 1 and 2, in a bridge having a three-dimensional structure parallel in the vertical direction, an upper layer portion 1a and a lower layer portion 1b are installed on the pier. Here, a case where the permanent scaffolding 11 is installed in the upper layer portion 1a will be described.

The girders 2a, 2b, and 2c are installed in each of the upper layer portion 1a and the lower layer portion 1b in the direction of the bridge axis. The girder 2a extends in the direction of the bridge axis on the outer side of the ring, the girder 2b extends in the direction of the bridge axis substantially at the center in the direction perpendicular to the bridge axis, and the girder 2c extends in the direction of the bridge axis on the inner side of the ring. The floor slabs 3a and 3b are installed on the girders 2a, 2b and 2c. Of the girders 2a, 2b, 2c of the upper layer 1a and the lower layer 1b, the inner and outer girders 2a, 2c are attached with arm members 4a, 4b arranged in parallel vertically in the direction perpendicular to the bridge axis. Specifically, arm members 4a and 4b are attached to the girder 2a toward the outside. Arm members 4a and 4b are also attached to the girder 2c on the inner side of the ring toward the outside. A side panel 5 is attached to the arm members 4a and 4b attached to the girders 2a and 2c.

On the girder 2b located at the center of the upper layer 1a, the arm member 6a is installed toward the girder 2a, and the arm member 6b is installed toward the girder 2c. Further, the girder 2a is provided with an arm member 7 extending in the direction of the girder 2b. A hanging member 21 is attached to each of the arm member 6a and the arm member 7, and vertical beams 8a and 8b extending in the direction of the bridge axis are suspended. Further, a hanging member 21 is attached to each of the arm member 6b and the arm member 4b on the inner ring side, and vertical beams 8c and 8d extending in the direction of the bridge axis are suspended.

The cross beams 9a are parallel to each other in the bridge axis direction and are bridged at equal intervals to the vertical beams 8a and 8b, and the cross beams 9b are parallel to each other in the bridge axis direction to the vertical beams 8c and 8d at equal intervals. It is bridged. The cross beam 9a and the cross beam 9b are divided below the central girder 2b, and the cross beam 9a and the cross beam 9b are connected at the split position. A back panel and a permanent scaffolding are installed on the cross beams 9a bridged over the vertical beams 8a and 8b and the cross beams 9b bridged over the vertical beams 8c and 8d. Here, a scaffolding panel 11a constituting the permanent scaffolding 11 is installed between the cross beams 9a and 9b. As described above, for example, in the upper layer portion 1a, in the upper layer portion 1a, the vertical beams 8a, 8b and the cross beams 9a suspended from the arm member 6a and the arm member 7 by the suspension member 21 are one grid-like frame 20 on the annular outer side. To configure. Further, on the inner side of the ring, the vertical beams 8c and 8d and the cross beams 9b suspended from the arm members 6b and the arm members 4b by the suspending members 21 form one lattice-shaped frame 20. In the frame 20, the vertical beams 8a to 8d are the upper beams, and the cross beams 9a and 9b are the lower beams.

An arm member 12 is installed in the girder 2b located at the center of the lower layer portion 1b toward the girder 2b. A hanging member 13 is attached to the arm member 12, and a vertical beam 8x extending in the direction of the bridge axis is suspended. The cross beam 9a and the cross beam 9b are connected, the cross beam 9a is suspended from the arm member 7 by the suspension member 13, and the cross beam 9b is suspended from the arm member 12 and the arm member 4b on the annular inner side by the suspension member 13. .. A back panel and a permanent scaffolding are installed on the cross beams 9a bridged over the vertical beams 8a and 8b and the cross beams 9b bridged over the vertical beams 8c and 8d. Here, a scaffolding panel 11a constituting the permanent scaffolding 11 is installed between the cross beams 9a and 9b. In the lower layer portion 1b, the cross beam 9b is formed longer than the cross beam 9a.

Between the upper layer 1a and the lower layer 1b, there is a building limit 10 which is a space range in which the installation of obstacles or structures on the road is not permitted in order to ensure traffic safety. Therefore, the permanent scaffolding 11 of the upper layer portion 1a is located outside the construction limit 10 of the lower layer portion 1b, that is, above.

Next, in the upper layer 1a, a scaffold forming a permanent scaffold 11 on a frame 20 composed of vertical beams 8a, 8b and cross beams 9a, and a grid-like frame 20 composed of vertical beams 8b, 8c and cross beams 9b. A method of installing the panel 11a will be described. Here, a method of installing the scaffolding panel 11a on the frame 20 composed of the vertical beams 8a and 8b and the cross beams 9a will be described as an example.

As shown in FIG. 3A, the arm member 7 is fixed to the girder 2a toward the girder 2b, and as shown in FIG. 3B, the girder 2b has an arm toward the girder 2a. The material 6a is fixed. Then, a hanging member 21 for suspending the vertical beam 8a is attached to the arm member 7, and a suspending member 21 for suspending the vertical beam 8b is attached to the arm member 6a.

The hanging member 21 is a long member having an L-shaped cross section, and includes a first piece 21a and a second piece 21b. As shown in FIG. 4A, the first piece 21a includes an adjusting hole 22, a lower fixing hole 23, and an upper fixing hole 24. The adjusting hole 22 is an elongated hole whose longitudinal direction is the hanging direction of the skeleton 20, and the length in the longitudinal direction is set to the size for suspending the skeleton 20. The lower fixing hole 23 is a round hole provided on the lower side of the adjusting hole 22. The upper fixing hole 24 is a round hole provided above the adjusting hole 22. The first piece 21a is a piece for fixing to the arm members 7, 6a. A connecting member 25 for fixing the lower end portion of the second piece 21b to the vertical beams 8a and 8b is attached. The connecting member 25 is an L-shaped member, includes a first connecting piece 25a and a second connecting piece 25b, and the first connecting piece 25a is bolted to the lower end of the second piece 21b with bolts and nuts. Further, the second connecting piece 25b is bolted to the upper flanges 19e of the vertical beams 8a and 8b.

As shown in FIGS. 3A and 3B, each of the arm member 6a and the arm member 7 is an integral part with the girders 2a and 2b, and is a support portion for suspending and supporting the frame 20. The arm members 7 and 6a are, for example, channel steel, and include a web 19a, an upper flange 19b, and a lower flange 19c. The base ends of the arm members 7 and 6a are fixed to the girders 2a and 2b and extend in the direction perpendicular to the bridge axis. Then, the first piece 21a is attached to the web 19a on the tip side. As shown in FIG. 4B, the web 19a is provided with a support hole formed of a round hole for fixing the first piece 21a. Specifically, the web 19a is provided with a first support hole 26a, a second support hole 26b, and a third support hole 26c arranged in a row from the bottom to the top.

As shown in FIG. 4C, before lowering the skeleton 20, the first bolt 27a is inserted into the lower fixing hole 23 and the first support hole 26a and bolted. Further, the second bolt 27b is inserted into the adjusting hole 22 and the second support hole 26b, and bolted at the lower end of the adjusting hole 22. As a result, the skeleton 20 is maintained at the first height H1.

When lowering the skeleton 20, the first bolt 27a is removed from the lower fixing hole 23 and the first support hole 26a. Further, the second bolt 27b also functions as a fixing member, and further, when the suspending member 21 is lowered downward, the second bolt 27b is loosened and moves from the lower end portion to the upper end portion of the adjusting hole 22. It functions as a guide member when 20 descends.

As shown in FIG. 4D, when the skeleton 20 is lowered, the first bolt 27a is inserted into the upper fixing hole 24 and the third support hole 26c and bolted. Further, the second bolt 27b is inserted into the adjusting hole 22 and the second support hole 26b, and bolted at the upper end of the adjusting hole 22. As a result, the skeleton 20 is maintained at the second height H2.

As shown in FIG. 5A, the upper flange 19b has a hanging piece 16 for hanging the upper hook 18a of the chain block 18 for hanging the vertical beams 8a and 8b with respect to the arm members 7 and 6a. It is bolted and the hanging piece 16 is provided with a jackle 27 as an engaging portion. The vertical beams 8a and 8b are shaped steels such as H steel and I steel, and an eyebolt 19d serving as an engaging portion is provided on the upper flange 19e. A lower hook 18b of the chain block 18, which is a hanging device, is installed between the jackle 27 and the eyebolt 19d.

As shown in FIG. 5B, the chain block 18 is a boosting mechanism using gears and pulleys, and is a device for raising and lowering a heavy object with a chain. Then, the jackle 27 is engaged with the upper hook 18a of the chain block 18, and the eyebolt 19d is engaged with the lower hook 18b. The suspension position P (see FIG. 2) in which the vertical beams 8a and 8b are suspended from the arm members 7 and 6a by the chain block 18 is a position close to the suspension member 21 and is relative to the suspension member 21. The vertical beams 8a and 8b, which are the upper beams, are positioned so as to extend in the extending direction. Then, the grid-shaped frame 20 is suspended by the chain block 18 at, for example, the corners of the frame 20, that is, four points. Further, the hanging position P may be set to 5 or more by suspending at a place other than the corner. Further, depending on the size of the skeleton 20, there may be three places.

As shown in FIG. 6A, a temporary scaffold 31 is installed on the upper layer 1a above the building limit 10 so as to cover the girders 2a, 2b, and 2c. In the temporary scaffold 31, arm members 7 and 6a are bolted to the girders 2a and 2b. Then, the hanging member 21 is bolted to the arm members 7 and 6a, the vertical beams 8a and 8b constituting the frame 20 are bolted to the hanging member 21, and further, the vertical beams 8a and 8b are bolted to the vertical beams 8a and 8b. The cross beams 9a are bolted together, thereby installing the skeleton 20.

Here, the positional relationship between the arm members 7 and 6a and the hanging member 21 will be described. As shown in FIG. 4B, the first bolt 27a is inserted into the lower fixing hole 23 and the first support hole 26a and bolted. Further, the second bolt 27b is inserted into the adjusting hole 22 and the second support hole 26b, and bolted at the lower end of the adjusting hole 22. As a result, the skeleton 20 is located at the first height H1 close to the girders 2a and 2b. The skeleton 20 is supported by the suspension member 21 at or near the four corners, and the positions in the bridge axis direction and the bridge axis perpendicular direction with respect to the girders 2a and 2b or the arm members 7 and 6a are determined. In this state, as shown in FIG. 5A, a chain block 18 is installed between the jackle 27 and the eyebolt 19d, and the skeleton 20 is lightly suspended by the chain block 18. .. As shown in FIG. 6B, after this, the temporary scaffold 31 is disassembled and removed.

Next, in the hanging member 21, the first bolt 27a is removed from the lower fixing hole 23 and the first support hole 26a. Further, the second bolt 27b is loosened with respect to the adjusting hole 22 and the second support hole 26b. That is, the hanging member 21 and the arm members 7, 6a are only connected by the loose second bolt 27b. As a result, the skeleton 20 is suspended from the chain block 18 and is in a state where it can descend from the first height H1 to the second height H2.

As shown in FIG. 7, in the work by the chain block 18, the aerial work platform 32 is arranged in the lower layer portion 1b, and the workbench 33 is raised to the height of the chain block 18. A telescopic scaffold, a gondola, or the like may be used. Then, the chain block 18 is operated by the operator, and the skeleton 20 is lowered from the first height H1 to the second height H2. The second height H2 is also lower than the first height H1 but above the building limit 10.

At this time, the four chain blocks 18 that suspend the skeleton 20 are operated at the same time so that the descent speed is the same as much as possible. As shown in FIGS. 8 and 9, when the skeleton 20 is lowered, the second bolt 27b moves from the lower end to the upper end of the adjusting hole 22, and at this time, the second bolt 27b lowers the skeleton 20. It functions as a guide member. Further, the first piece 21a of the hanging member 21 is in surface contact with the web 19a. Therefore, the skeleton 20 can be prevented from swinging in the direction of the bridge axis when descending.

Then, as shown in FIG. 4C, at the second height H2, the first bolt 27a is inserted into the upper fixing hole 24 and the third support hole 26c and bolted. Further, the adjustment hole 22 and the second bolt 27b inserted through the second support hole 26b are bolted at the upper end of the adjustment hole 22. The bolts fastened to the upper fixing hole 24 and the third support hole 26c may be different from the first bolt 27a.

By the way, the hanging position P of the frame 20 by the chain block 18 is a hanging position of the hanging piece 16 provided for the arm members 7 and 6a from the jackle 27, and is an upper beam with respect to the hanging member 21. It is a position shifted in the extending direction of the vertical beams 8a and 8b. The hanging position P is close to the hanging member 21. Therefore, even if the descent speed of the skeleton 20 by the chain block 18 varies at the plurality of suspension positions P, the inclination of the skeleton 20 is smaller than that when the suspension position P is separated from the suspension member 21. can do.

As shown in FIG. 10, when the skeleton 20 is lowered from the first height H1 to the second height H2, the aerial work platform 32 of the lower layer portion 1b is then moved, and the workbench 33 is moved to the upper layer portion 1a. The side panel 5 is installed by moving it to the side surface. After that, as shown in FIG. 11, the workbench 33 is bridged and fixed between the cross beams 9a on the frame 20 of the upper layer 1a, and the permanent scaffolding 11 is completed.

The above-described embodiment can obtain the effects listed below.
(1) The skeleton 20 is assembled in the temporary scaffolding 31 installed above the building limit 10, and is lowered to the second height H2 as it is. Therefore, even in a place where the space under the upper layer 1a is narrow and the height of the temporary scaffolding is limited by the building limit 10, it is possible to install the permanent scaffolding 11 having a sufficient space under the girder. it can.

(2) The skeleton 20 is installed at the first height H1, then lowered to the second height H2, and then the scaffold panel 11a for the permanent scaffold 11 is installed. Therefore, the construction period can be shortened.

(3) The skeleton 20 is lowered from the first height H1 to the second height H2 in a state of being aligned in the bridge axis direction and the bridge axis perpendicular direction with respect to the girders 2a and 2b or the arm members 7 and 6a. Can be maintained at times.

(4) When the temporary scaffolding 31 is installed in accordance with the case where the permanent scaffolding is directly provided at the second height H2, the temporary scaffolding is subject to the construction limit 10, but here, the framework is set at the first height H1. Temporary scaffolding 31 is installed according to the case of assembling 20. Therefore, the temporary scaffolding 31 can be provided above the building limit 10.

(5) When the skeleton 20 descends from the first height H1 to the second height H2, the hanging member 21 can make the second bolt 27b engaged with the adjusting hole 22 function as a guide member. Then, when the skeleton 20 descends, at least the sway of the skeleton 20 in the bridge axis direction can be suppressed.

(6) The second height H2 can be defined by the dimension of the adjusting hole 22 in the longitudinal direction. That is, the skeleton 20 may be lowered until the second bolt 27b abuts on the upper end of the adjusting hole 22. Therefore, the heights of the four points of the skeleton 20 can be easily aligned with the second height H2.

(7) The hanging position P of the frame 20 by the chain block 18 is close to the hanging member 21. Therefore, even if the descent speed of the skeleton 20 by the chain block 18 varies, the inclination of the skeleton 20 can be made smaller than when the hanging position P is separated from the hanging member 21.

The above embodiment can be further modified as appropriate, for example, as follows.
FIG. 12A is a modification of the support holes provided in the web 19a, which is an example of two support holes instead of three. Specifically, the web 19a is provided with a first support hole 26a and a second support hole 26b arranged one above the other from the bottom.

As shown in FIG. 12B, before lowering the skeleton 20, the first bolt 27a is inserted into the lower fixing hole 23 and the first support hole 26a and bolted. Further, the second bolt 27b is inserted into the adjusting hole 22 and the second support hole 26b, and bolted at the lower end of the adjusting hole 22.

When the skeleton 20 is lowered, the first bolt 27a is removed from the lower fixing hole 23 and the first support hole 26a, and the second bolt 27b is in a loosened state. Then, as shown in FIG. 12 (c), when the suspending member 21 is slightly lowered, the first bolt 27a is inserted into the adjusting hole 22 and tightened in the first support hole 26a in a loose state. As a result, the second bolt 27b and the first bolt 27a are inserted into the adjusting hole 22 and each serves as a guide member. Then, it becomes difficult to shake in the direction perpendicular to the bridge axis.

Then, as shown in FIG. 12D, the skeleton 20 is lowered until the second bolt 27b abuts on the upper end of the adjusting hole 22. Then, as shown in FIG. 12E, the second bolt 27b is removed, and the first bolt 27a is slightly lowered until it hits the upper end of the adjusting hole 22. After that, the second bolt 27b is inserted into the upper fixing hole 24 and the second support hole 26b and bolted. Further, the first bolt 27a is bolted at the upper end of the adjusting hole 22.

According to the above example, when the skeleton 20 is lowered from the first height H1 to the second height H2, two of the second bolt 27b and the first bolt 27a are inserted into the adjusting hole 22. Therefore, it is possible to suppress the shaking in the direction perpendicular to the bridge axis. Further, the hanging member 21 can be fixed to the arm member with two bolts.

The lower fixing hole 23 and the first bolt 27a removed from the first support hole 26a when the skeleton 20 is lowered are not reused, and after the skeleton 20 is lowered, the adjusting hole 22 and the first support hole 26a are used. Alternatively, another bolt may be tightened in a loosened state. Further, after tightening the first bolt 27a or a substitute bolt in the adjusting hole 22 and the first support hole 26a in a loose state, the second bolt 27b may be removed, and then the skeleton 20 may be lowered. .. That is, at the time of descent, only one bolt serving as a guide member may be engaged with the adjusting hole 22. Further, at the second height H2, the bolt inserted into the upper fixing hole 24 and the second support hole 26b may be another bolt instead of the second bolt 27b.

-In FIG. 13A, three support holes provided in the web 19a are provided. That is, the web 19a is provided with the first support hole 26a, the second support hole 26b, and the third support hole 26c arranged in a row from the bottom.

The hanging member 21 includes an adjusting hole 22, a lower fixing hole 23, and an upper fixing hole 24. Further, a lower additional fixing hole 41 is provided on the lower side of the lower fixing hole 23, and an upper additional fixing hole 42 is provided on the upper side of the upper fixing hole 24.

As shown in FIG. 13B, before lowering the skeleton 20, the first bolt 27a is inserted into the lower additional fixing hole 41 and the first support hole 26a and bolted. Further, the second bolt 27b is inserted into the lower fixing hole 23 and the second support hole 26b and bolted. Further, the third bolt 27c is inserted into the adjusting hole 22 and the third supporting hole 26c, and bolted at the lower end of the adjusting hole 22.

When lowering the skeleton 20, the first bolt 27a is removed from the lower additional fixing hole 41 and the first support hole 26a, and the second bolt 27b is removed from the lower fixing hole 23 and the second support hole 26b. .. In addition, the third bolt 27c is loosened. Then, as shown in FIG. 13C, when the suspending member 21 is slightly lowered, the first bolt 27a and the second bolt 27b are inserted into the adjusting hole 22 and tightened in the first support hole 26a in a loose state. Be done. As a result, the third bolt 27c, the second bolt 27b, and the first bolt 27a are inserted into the adjusting hole 22, and each of them serves as a guide member. Then, it becomes difficult to shake in the direction perpendicular to the bridge axis.

Then, as shown in FIG. 13D, the skeleton 20 is lowered until the third bolt 27c abuts on the upper end of the adjusting hole 22. Then, as shown in FIG. 13E, the third bolt 27c and the second bolt 27b are removed, and the first bolt 27a is slightly lowered until it hits the upper end of the adjusting hole 22. After that, the second bolt 27b is inserted into the upper fixing hole 24 and the second support hole 26b and bolted, and the third bolt 27c is inserted into the upper additional fixing hole 42 and the third support hole 26c and bolted. Further, the first bolt 27a is bolted at the upper end of the adjusting hole 22.

According to the above example, when the skeleton 20 is lowered from the first height H1 to the second height H2, the adjusting hole 22 has 3 of the 3rd bolt 27c, the 2nd bolt 27b and the 1st bolt 27a. One is inserted. In addition, it is possible to suppress the shaking in the direction perpendicular to the bridge axis as compared with the case where one or two bolts are inserted. Further, at the second height H2, the hanging member 21 can be fixed to the arm member with three bolts.

The lower additional fixing hole 41 and the first bolt 27a removed from the first support hole 26a when the skeleton 20 is lowered are not reused, and the adjusting hole 22 and the first support hole 26a are separated from each other. The bolts may be tightened in a loosened state. Similarly, the second bolt 27b removed from the lower fixing hole 23 and the second support hole 26b is not reused, and another bolt is loosely tightened to the adjusting hole 22 and the second support hole 26b. You may do so. Further, when lowering the skeleton 20, only the first bolt 27a may be tightened in the adjusting hole 22 and the first support hole 26a in a loose state. Further, at the second height H2, the bolt inserted into the upper fixing hole 24 and the second support hole 26b may be another bolt instead of the second bolt 27b. Further, at the second height H2, the bolt inserted into the upper additional fixing hole 42 and the third support hole 26c may be another bolt instead of the third bolt 27c.

The member that functions as the guide member of the hanging member 21 is not limited to the bolt, and its configuration is particularly limited as long as it is a member that can engage with the adjusting hole 22 and guide the descent of the hanging member 21. is not it.

-As in the above embodiment, when the vertical beams 8a to 8d are the upper beams and the cross beams 9a and 9b are the lower beams, the suspension member 21 is not the upper beams 8a to 8d but the vertical beams 8a to 8d. The hanging member 21 may be connected to the cross beams 9a and 9b which are the lower beams. Then, the chain block 18 may also be arranged between the arm members 7 and 6a and the cross beams 9a and 9b which are the lower beams.

-In the above embodiment, the vertical beams 8a to 8d are the upper beams and the cross beams 9a and 9b are the lower beams, but conversely, the cross beams 9a and 9b are the upper beams and the vertical beams 8a. ~ 8d may be the lower beam. In this case as well, the suspending member 21 may be connected to the horizontal beams 9a and 9b which are the upper beams, or may be connected to the vertical beams 8a to 8d which are the lower beams. Then, the chain block 18 may also be arranged between the arm members 7 and 6a and any of the upper beams 9a and 9b and the lower beams 8a to 8d.

The framework 20 may be configured such that only the vertical beams 8a to 8d are used and the horizontal beams 9a and 9b are omitted. In this case, a temporary material may be arranged instead of the horizontal beams 9a and 9b, and the scaffolding panel 11a may be arranged using the vertical beams 8a to 8d and the temporary material.

Further, only the horizontal beams 9a and 9b may be used, and the vertical beams 8a to 8d may be omitted. In this case, a temporary material may be arranged instead of the vertical beams 8a to 8d, and the scaffolding panel 11a may be arranged using the temporary material or the horizontal beams 9a and 9b.

-The skeleton 20 may be lowered to the second height H2, and then all the scaffolding panels 11a may be installed on the skeleton 20. Further, when the first height is H1, a part of the scaffolding panel 11a is installed on the skeleton 20, the skeleton 20 is lowered to the second height H2, and then the remaining scaffolding panel 11a is installed on the skeleton 20. You may try to do it.

After lowering the skeleton 20 to the second height H2, the hanging material 21 may be replaced with a permanently used hanging material.
-The suspension position P for suspending one frame 20 with the chain block 18 and / or the suspension position P for suspending with the suspension member 21 may be three locations or five or more locations.

-The suspended object to be installed under the bridge using the suspending material 21 may be not only a permanent scaffold but also a bridge accessory such as an inspection road, a drainage device, and an accessory.

1a ... upper layer part, 1b ... lower layer part, 2a-2c ... girder, 3a, 3b ... floor slab, 4a, 4b ... arm material, 5 ... side panel, 6a, 6b ... arm material, 7 ... arm material, 8a-8d , 8x ... Vertical beam, 9a, 9b ... Horizontal beam, 10 ... Building limit, 11 ... Permanent scaffolding, 11a ... Scaffolding panel, 12 ... Arm material, 13 ... Hanging material, 16 ... Hanging piece, 18 ... Chain block, 18a ... Upper hook, 18b ... Lower hook, 19a ... Web, 19b ... Upper flange, 19c ... Lower flange, 19d ... Eyebolt, 19e ... Upper flange, 20 ... Frame, 21 ... Hanging material, 21a ... 1st piece, 21b ... 2nd Piece, 22 ... Adjusting hole, 23 ... Lower fixing hole, 24 ... Upper fixing hole, 25 ... Connecting material, 25a ... First connecting piece, 25b ... Second connecting piece, 26a ... First support hole, 26b ... Second Support hole, 26c ... 3rd support hole, 27 ... Jackle, 27a ... 1st bolt, 27b ... 2nd bolt, 27c ... 3rd bolt, 31 ... Temporary scaffolding, 32 ... Aerial work platform, 33 ... Worktable, 41 ... Lower additional fixing hole, 42 ... Upper additional fixing hole.

Claims (8)

It is an installation method to install a permanent scaffolding under the bridge.
Outside the building limits, the process of installing the frame of the permanent scaffolding at the first height with a hanging material that connects the support part of the girder and the frame.
Outside the building limit, the skeleton is lowered from the first height to the second height by a suspension device, and the skeleton is installed at the second height with the suspension material.
A method of installing a permanent scaffold in which the skeleton is lowered from the first height to the second height in a state where the skeleton is aligned with the girder by the suspending material. Under the bridge, the skeleton is installed at the first height in a temporary scaffold installed outside the building limit.
The method for installing a permanent scaffold according to claim 1, wherein the skeleton is lowered to the second height after the temporary scaffold is disassembled. The hanging material is at least
It is provided with an adjusting hole, a lower fixing hole located below the adjusting hole, and an upper fixing hole located above the adjusting hole, and the adjusting hole is an elongated hole extending in the hanging direction of the skeleton. The lower fixing hole and the upper fixing hole are made of round holes.
When the skeleton is at the first height, the suspending material is fixed to the support portion at the lower fixing hole and the lower end portion of the adjusting hole.
When the skeleton is lowered from the first height to the second height, the fixing in the lower fixing hole is released, and then the fixing member located at the lower end of the adjusting hole is loosened and the fixing is performed. The suspension member is lowered with respect to the support portion so that the member acts as a guide member and moves to the upper end portion of the adjustment hole.
The method for installing a permanent scaffold according to claim 1 or 2, wherein the suspending material is fixed to the support portion at the upper end portions of the upper fixing hole and the adjusting hole. The method for installing a permanent scaffold according to claim 3, wherein a plurality of guide members are engaged with the adjusting hole when the skeleton is lowered from the first height to the second height. The framework includes a vertical beam extending in the direction of the bridge axis and a cross beam extending in the direction perpendicular to the bridge axis, one of which is an upper beam located on the upper side and the other of which is a lower beam located below the upper beam. And
The suspension member is connected to one of the upper beam and the lower beam, and the suspension device is arranged between the support portion and the one beam member.
The permanent scaffold according to any one of claims 1 to 4, wherein the suspension position of the one beam material by the suspension device is deviated from the suspension material in the extending direction of the one beam material. Installation method. The upper beam is the vertical beam, the lower beam is the horizontal beam, and the like.
The hanging material is connected to the support portion and the vertical beam.
The suspension device is arranged between the support portion and the vertical beam, and is arranged.
The permanent scaffolding installation method according to claim 5, wherein the suspension position of the upper beam by the suspension device is deviated in the direction in which the vertical beam extends with respect to the suspension material. The skeleton comprises at least one of a vertical beam extending in the direction of the bridge axis and a cross beam extending in the direction perpendicular to the bridge axis.
The suspension material is connected to the beam material, and the suspension device is arranged between the support portion and the beam material.
The permanent scaffolding installation method according to any one of claims 1 to 4, wherein the suspension position of the beam material by the suspension device is deviated from the suspension material in the extending direction of the beam material. It is an installation method that installs accessories under the bridge.
A process of installing the accessory at the first height with a hanging material connecting the support portion of the girder and the accessory outside the building limit.
The process of suspending the accessory with a suspension device and
A step of lowering the accessory from the first height to the second height by a suspension device and installing the accessory at the second height with the suspension material outside the building limit is provided.
A method for installing a bridge accessory in which the accessory is lowered from the first height to the second height in a state where the accessory is aligned with the girder by the suspension material.