JP7323480B2 - Permanent scaffold installation method and back panel - Google Patents

Description

The present invention relates to a permanent scaffolding installation method and a back panel installed under a bridge.

As described in Patent Document 1, etc., in bridge inspections, permanent scaffolding is installed under the bridge to minimize traffic closures and lane restrictions, and to reduce labor and installation costs. For example, in the method of installing a permanent scaffold described in Patent Document 1, first, louvers and folded plates are fixed to a grid-like frame composed of vertical and horizontal beams, and a panel having a predetermined size is formed. Assemble unitized permanent scaffolding panels. Next, the permanent scaffolding panel is reinforced with a single pipe, and temporarily suspended from a steel girder using an aerial work vehicle or a lifting device. Then, permanent scaffolding is installed under the bridge by using the permanent scaffolding panel as a scaffolding and replacing it with the permanent suspension material. In addition, a new permanent scaffolding panel is sent out in the direction of the bridge axis to the already temporarily suspended permanent scaffolding panel.

JP 2019-7206 A

When installing permanent scaffolding, there is a demand for a construction method that can shorten the construction period by further shortening the work time required for traffic closures and lane restrictions. For example, it is desired to shorten the work using aerial work vehicles and lifting equipment by closing traffic.

The present invention has been made to solve the above problems, and its purpose is to provide a permanent scaffolding installation method and a back panel that can shorten the number of days of road closures and lane restrictions and the construction period. .

A method of installing a permanent scaffolding to solve the above problems is an installation method of installing a permanent scaffolding under a bridge. A step of suspending the frame configured by passing and temporarily fixing the frame from the main girder constituting the bridge with a temporary wire rod, installing a back panel between the vertical beams after suspending the frame, and After installing the back panel, a step of permanently installing a suspension member between the main girder and the vertical beam; and a step of removing the temporary strip member and the temporary wire member after permanently installing the suspension member. According to the above configuration, the frame is loaded without the back panel installed and then temporarily suspended, which facilitates the work and shortens the work time.

In the method for installing a permanent scaffold, the frame includes a first frame and a second frame arranged next to the first frame in the bridge axis direction, and the first frame is suspended by the temporary wire. a step of temporarily placing the second frame on the first frame after installing the back panel; The steps of delivering to adjacent positions and connecting the longitudinal beams of the first frame and the longitudinal beams of the second frame and installing the back panel on the second frame may be provided. According to the above configuration, the second frame can be successively sent out in the direction of the bridge axis in a lightweight state without the rear panel installed, using the rear panel of the first frame as a scaffold. Therefore, the work concerned is facilitated, and the number of days of road closures and lane restrictions can be shortened.

In the method for installing a permanent scaffold, the back panel includes a first back panel, a second back panel installed next to the first back panel in the bridge axis direction, and the second back panel in the bridge axis direction. and a third back panel installed next to the panel, wherein after installing the first panel between the longitudinal beams, the second back panel is placed at a position adjacent to the first back panel. a step of sending out the second back panel in the bridge axis direction to make a space adjacent to the first back panel a vacant space; and a step of placing the third back panel in the vacant space. may be provided. According to the above configuration, the rear panels can be easily arranged side by side in the bridge axis direction between the vertical beams by sliding them one by one.

The back panel used in the permanent scaffolding installation method is a portion of the back panel that is supported in contact with the longitudinal beams, and the corner of the side that intersects the direction in which the back panel is sent out is an R surface or You may make it comprise by C surface. According to the above configuration, even if the longitudinal beam has a convex portion or the like, it can be easily overcome by the R surface or C surface of the corner, and can slide smoothly.

The back panel used in the method for installing the permanent scaffolding may include a drop-off prevention portion that engages edges extending in the bridge axis direction of the adjacent longitudinal beams. According to the above configuration, even when the back panel is slid, it can be made difficult to fall out from between the vertical beams.

In the method for installing a permanent scaffolding, one of the vertical beams adjacent to each other is an end vertical beam, and after installation of the back panel, a support is installed on the end vertical beam and attached to the support. and a step of connecting the main girder and the strut with an arm member. , the temporary strip and the temporary wire may be removed. According to the above configuration, a permanent scaffolding can be installed even on the projecting portion of the bridge in the direction perpendicular to the bridge axis.

According to the present invention, it is possible to shorten the number of days of road closures and lane restrictions for installing a permanent scaffolding, as well as the construction period.

The figure which shows the state which suspended temporarily with the chain the frame comprised by extending the single pipe pipe over the longitudinal beam in the direction perpendicular to a bridge axis, and temporarily fixing in a span part. FIG. 2 is a continuation of FIG. 1 and shows a state in which a back panel is installed between longitudinal beams; The perspective view which shows the state which installed the back panel between vertical beams. FIG. 4 is a continuation of FIG. 3 and is a perspective view showing a state in which the next second frame is temporarily placed on the first frame; FIG. 5 is a continuation of FIG. 4 and a perspective view showing a state in which the first back panel is placed on the second frame; FIG. 6 is a continuation of FIG. 5 and is a perspective view showing a state in which the next back panel is placed on the second frame; FIG. 3 is a continuation of FIG. 2 and shows a state in which the hanging member is permanently installed; The figure which is a continuation of FIG. 7 and shows the state which removed the chain and the single pipe. The figure which shows the state which hung the frame with the chain in the overhang part provided in the both ends of the bridge axis right angle direction. FIG. 10 is a continuation of FIG. 9 and shows a state in which a back panel is installed between the longitudinal beam and the end longitudinal beam, and a support and a side panel are installed on the end longitudinal beam; FIG. 11 is a continuation of FIG. 10 and shows a state in which the hanging member and the arm member are permanently installed; FIG. 12 is a continuation of FIG. 11 and shows a state in which the chain and the single pipe are removed; The side view which expands and shows the state where the back panel was mounted on the vertical beam. The front view which shows the positional relationship of the side edge part of a vertical beam, and the fall-off prevention part of a back panel.

Hereinafter, a method for installing a permanent scaffolding to which the present invention is applied will be described with reference to the drawings.
As shown in FIG. 1, the permanent scaffolding to which the present invention is applied is a scaffolding installed under a bridge and installed on the main girder 11 of the bridge that supports the floor slab. The following describes how to install a permanent scaffold.

[First Embodiment]
As shown in FIG. 1, the main girders 11 here extend in the direction of the bridge axis, and are arranged in parallel with each other in the direction perpendicular to the axis. The main girder 11 is made of I-shaped steel or the like. First, the frame 12 is suspended from the main girder 11 by the chain 15 which is a temporary wire rod. The frame 12 includes vertical beams 13 and single pipes 14 as temporary members. The vertical beams 13 are beams extending in the direction of the bridge axis, and are H-shaped steel as an example. Here, three vertical beams 13 are arranged in the direction perpendicular to the bridge axis. A plurality of single pipes 14 are bridged over the longitudinal beams 13 and extend in the direction perpendicular to the bridge axis. Each single pipe 14 is temporarily fixed to each vertical beam 13 by a clamp or the like. The frame 12 is configured in a grid pattern with vertical beams 13 and single pipes 14 . The single pipe 14 suppresses each vertical beam 13 from swinging when suspended from the main girder 11 . In addition, the intervals in the direction perpendicular to the bridge axis are made constant and the height of each longitudinal beam 13 is made constant. A back panel 16 will eventually be installed between the longitudinal beams 13 adjacent to each other, but the back panel 16 is not installed at this stage.

The frame 12 is lifted to an existing permanent scaffolding under the bridge by an aerial work vehicle, a lifting device, or manually, and suspended from the main girder 11 by the chain 15 . The chain 15 has one end connected to a suspender 15 a provided on the main girder 11 and the other end connected to a suspender provided on the longitudinal beam 13 or the single pipe 14 . The other end of the chain 15 can also be connected to a suspender provided on both the vertical beam 13 and the single pipe 14 . The chain 15 is strong enough to hang the frame 12 and the rear panel 16 in the installed state. The weight of the frame 12 is reduced by not installing the back panel 16 at this stage, and this makes it possible to shorten the work of loading the existing permanent scaffolding with an aerial work vehicle, a lifting device, or human power.

As shown in FIG. 2, a back panel 16 is installed between the vertical beams 13 adjacent to each other on the frame 12 temporarily suspended from the main girder 11 by the chain 15 . As shown in FIG. 3, the back panel 16 is a rectangular plate and is installed between the vertical beams 13 so that its longitudinal direction is perpendicular to the bridge axis. The vertical beams 13 are H-shaped steel, and the short sides of the back panel 16 are supported by the lower flanges 13a. The back panels 16 are arranged side by side in the bridge axis direction between the longitudinal beams 13 . Here, when the back panel 16 is installed on one frame 12 (hereinafter also referred to as "first frame 12x"), the first frame 12x is attached to the next frame 12 (hereinafter referred to as "second frame 12y"). ) are connected to form a scaffolding for installing the back panel 16 on the second frame 12y.

Like the first frame 12x, the second frame 12y includes vertical beams 13 and single pipes 14 as temporary members. As shown in FIG. 4, the assembled second frame 12y is temporarily suspended from the main girder 11 by chains 15x to a temporary placement position on the first frame 12x. , or may be manually assembled on the first frame 12x. The second frame 12y is temporarily placed on the first frame 12x and suspended by the chain 15. As shown in FIG. One end of the chain 15y for suspending the second frame 12y is provided on the main girder 11 existing in the space above the frame adjacent position where the second frame 12y adjacent to the first frame 12x in the bridge axis direction is to be arranged. It is connected to the lower fitting 15a. The other end of the chain 15 is connected to the hanger of the second frame 12y on the first frame 12x. Therefore, when the second frame 12y is on the first frame 12x, the chain 15y extends from the suspender 15a provided on the main girder 11 existing in the space above the frame adjacent position to the suspender of the second frame 12y. It extends diagonally in the direction

As shown in FIG. 5, using the first frame 12x as a scaffold, the second frame 12y is pulled from a position on the first frame 12x to a position adjacent to the frame by being pulled by chains 15y. After that, the vertical beams 13 of the first frame 12x and the vertical beams 13 of the second frame 12y are connected by bolting or the like. Since the second frame 12y does not have the back panel 16 and is lightweight, the work of sending out the second frame 12y can be done manually without installing a winch or a trolley. In this state, the back panel 16 is not yet installed on the second frame 12y. Therefore, next, the back panel 16 is installed on the second frame 12y.

Here, the back panel 16 installed on the first frame 12x is the first back panel 16x. A position between the longitudinal beams 13 of the second frame 12y and adjacent to the first back panel 16x closest to the second frame 12y in the first frame 12x is the panel adjacent position. Using the first back panel 16x of the first frame 12x as a foothold, the first second back panel 16y is placed on the second frame 12y. That is, it is supported by the lower flange 13a of the longitudinal beam 13. As shown in FIG. After that, the second back panel 16y is slid in the direction of the bridge axis, and the position where the second back panel 16y was located becomes the empty space 19. As shown in FIG. As shown in FIG. 6, the next third back panel 16z is placed in this empty space 19. As shown in FIG. If more back panels 16 are to be placed, this operation is repeated. Since the work of installing the rear panels 16 is the work of installing the rear panels 16 one by one between the vertical beams 13, it can be easily done manually without installing a winch or a trolley.

The delivery of the frame 12 and the installation of the back panel 16 are performed by repeating the above steps. Each back panel 16 is sequentially fixed to the longitudinal beam 13 with fasteners or the like.

As shown in FIG. 7, the vertical beams 13 of the frame 12 in which the back panel 16 is installed between the vertical beams 13 are permanently provided with hangers 18 via arms 17, and are rebuilt from the chains 15. . Specifically, an arm member 17 extending in a direction perpendicular to the bridge axis is installed on the main girder 11 by bolting or the like, and a hanging member 18 is permanently installed between the arm member 17 and the longitudinal beam 13 by bolting or the like. . After that, as shown in FIG. 8, the single pipe 14 and the chain 15 are removed. Thus, by installing the back panel 16 on the longitudinal beam 13, a permanent scaffold is installed.

The above-described first embodiment can obtain the following effects.
(1-1) The frame 12 is loaded without the back panel 16 installed, and then suspended temporarily. The frame 12 is lighter because the back panel 16 is not attached. Therefore, the work concerned becomes easy and can be completed in a short time. As a result, the time for road closures and vehicle restrictions can be shortened.

(1-2) The frame 12 can be sent out sequentially in the direction of the bridge axis in a lightweight state without the back panel 16 installed, using the back panel 16 of the previously installed frame 12 as a foothold. Therefore, it can be done manually without installing a winch or a trolley. This facilitates the work and shortens the number of days of traffic closures and lane restrictions. In addition, even on a river, the frame 12 can be delivered sequentially from the axial end of the bridge toward the center of the river.

(1-3) Between the vertical beams 13, the rear panels 16 can be slid one by one so that they can be easily arranged side by side in the bridge axis direction by human power. Therefore, the work of installing the back panel 16 is also facilitated.

[Second embodiment]
2nd Embodiment is the installation method of the permanent scaffolding in the overhang|hanging part of the bridge axis right angle direction of a bridge. As shown in FIG. 9, here, the leftmost vertical beam is the end vertical beam 13x. Here, in the frame 12, a plurality of single pipes 14 are spanned over the two vertical beams 13 and the left end vertical beam 13x and temporarily fixed by clamps. Then, under the bridge, the frame 12 is lifted to an existing permanent scaffolding by an aerial work vehicle, a lifting device, or manually, and suspended from the main girder 11 by the chain 15 . A back panel 16 is installed between the longitudinal beams 13 adjacent to each other on the frame 12 temporarily suspended from the main girder 11 by the chain 15 .

As shown in FIG. 10, struts 21 are fixed to the longitudinal end beams 13x at predetermined intervals in the bridge axis direction. Then, as shown in FIG. 11, the strut 21 is also connected to the main girder 11 by the chain 15z and reinforced. Also, the strut 21 is connected and reinforced by the main girder 11 and the single pipe 14x. Then, side panels 22 of the bridge are sequentially installed on the supports 21 using fixing metal fittings or the like.

Next, suspension members 18 are permanently provided on the vertical beams 13 of the frame 12 via arms 17 . Also, the strut 21 and the main girder 11 are connected via an arm member 23 . As a result, the chains 15 and 15z are replaced. After that, as shown in FIG. 12, the single pipes 14, 14x and the chains 15, 15z are removed. Thus, by installing the back panel 16 on the vertical beam 13, a permanent scaffolding is also installed on the projecting portion of the bridge in the direction perpendicular to the bridge axis.

The above-described second embodiment can obtain the following effects.
(2-1) Permanent scaffolding can also be installed on overhangs in the direction perpendicular to the bridge axis.
(2-2) By connecting the strut 21 and the main girder 11 with the chains 15, 15z and the single pipes 14, 14x, the strut 21 and the side panel 22 can be reinforced during the installation work of the permanent scaffolding.

[Third embodiment]
The back panels 16 used in the first embodiment and the second embodiment are arranged side by side by sliding between the longitudinal beams 13 adjacent to each other. Specifically, the back panel 16 is slid over the lower flange 13a of the vertical beam 13 . As shown in FIG. 13, the back panel 16 has a bottom portion of the short side portions on both sides in the longitudinal direction that is in sliding contact with the lower flange 13a. A corner portion 24 of a long side that intersects the feeding direction of the back panel 16 is formed of an R surface.

Further, as shown in FIG. 14, on the bottom surface of the back panel 16, a drop-off prevention portion 25 is positioned between the tips of the lower flanges 13a to prevent the back panel 16 from falling out from between the longitudinal beams 13. Prepare. The drop-off preventing portion 25 is a protruding portion that protrudes from the bottom surface of the back panel 16 . Here, the relationship between the length b of the overlapping portion of the back panel 16 and the lower flange 13a and the distance a between the drop-off prevention portion 25 and the tip of the lower flange 13a is a<b. .

The above-described third embodiment can obtain the following effects.
(3-1) Even if the lower flange 13a has a projection or the like, the rear panel 16 can easily get over the curved surface of the corner 24 of the long side and slide smoothly.

(3-2) The back panel 16 can be prevented from falling out from between the vertical beams 13 by the falling-off preventing portion 25 even when it is slid between the vertical beams 13 . Even after the permanent scaffolding is installed, it is possible to prevent the back panel 16 from slipping out of the longitudinal beams 13 due to vibration or the like.

(3-3) Since the length b of the overlapped portion of the back panel 16 and the lower flange 13a is greater than the distance a between the drop-off prevention portion 25 and the tip of the lower flange 13a, the back panel 16 can be It is possible to prevent the back panel 16 from falling out from between the vertical beams 13 even if it is biased toward the vertical beams 13.例文帳に追加

Note that the first to third embodiments can be modified as appropriate, for example, as follows.
The step of temporarily suspending the frame 12 at the span portion of the first embodiment and the step of temporarily suspending the frame 12 at the projecting portion of the second embodiment may be performed in parallel, or the construction method of the first embodiment may be performed. After installing the permanent scaffolding on the span, the permanent scaffolding on the overhanging portion in the second embodiment may be installed. Conversely, after installing the permanent scaffolding of the overhanging portion in the second embodiment, the permanent scaffolding may be installed in the span portion by the construction method of the first embodiment.

- In the second embodiment, the single pipe 14x and the chain 15z that reinforce the column 21 may be omitted, or either the single pipe 14x or the chain 15z may be omitted.

・On the back panel 16, the drop-off prevention part 25 may be provided in a projecting shape near the tip of the lower flange 13a, or may be provided along the long side over the entire area between the tips of the lower flange 13a. It may be an extended protrusion. The drop-off preventing portion 25 may be omitted.

- In the back panel 16, the corner portion 24 may be a C surface.
- In the back panel 16, the corner portion 24 may not have the R surface or the C surface.
- The back panel 16 does not have to follow the procedure of sliding between the vertical beams 13 to provide an empty space 19 and installing a new back panel 16 in the empty space 19 . That is, the rear panels 16 may be installed so as to be arranged in order in the direction of the bridge axis.

- Chains 15 and 15z as temporary wires may be wire rods such as wire ropes that have the strength necessary for suspension support.
- The single pipe pipes 14, 14x as temporary materials may be replaced with wire ropes or the like. In addition, the number of the single pipes 14 that span between the longitudinal beams 13 and the number of the single pipes 14x that connect the struts 21 and the main girders 11 are particularly limited as long as they have sufficient strength to perform the reinforcing function. isn't it.

- The arm member 17 may be omitted depending on the location, or may have a different configuration.

11 Main girder 12 (12x, 12y) Frame 13 Vertical beam 13a Lower flange 13x Vertical end beam 14, 14x Single pipe 15 (15x, 15y), 15z Chain 16 (16x, 16y, 16z) Back panels 17, 23 Arm member 18 Suspension member 19 Empty space 21 Strut 22 Side panel 24 Corner portion 25 Drop-off prevention portion

Claims (6)

An installation method for installing a permanent scaffold under a bridge,
a step of suspending a frame, which is constructed by temporarily fixing temporary members across adjacent longitudinal beams extending in the direction of the bridge axis in a direction perpendicular to the bridge axis, from the main girder constituting the bridge with temporary wires;
installing a back panel between the longitudinal beams after hanging the frame;
After installing the back panel, a step of permanently installing hanging members between the main girder and the longitudinal beam;
A method for installing a permanent scaffolding, comprising removing the temporary material and the temporary wire after permanently installing the hanging material. The frame comprises a first frame and a second frame arranged next to the first frame in the bridge axis direction,
a step of temporarily placing the second frame on the first frame after suspending the first frame with the temporary wire and installing the back panel;
The second frame is suspended by the temporary wire rods, sent to a position adjacent to the first frame in the bridge axis direction, and the longitudinal beams of the first frame and the longitudinal beams of the second frame are connected. and
2. The method of installing a permanent scaffold according to claim 1, comprising installing the back panel on the second frame. The back panel includes a first back panel, a second back panel installed next to the first back panel in the bridge axis direction, and a second back panel installed next to the second back panel in the bridge axis direction. 3 back panel,
After installing the first back panel between the longitudinal beams, placing the second back panel at a position adjacent to the first back panel;
a step of sending out the second back panel in the direction of the bridge axis to make a position adjacent to the first back panel empty space;
and placing the third rear panel in the empty space. one of the longitudinal beams adjacent to each other is an end longitudinal beam;
After installation of the back panel, installing a stanchion against the end longitudinal beam and installing a side panel against the stanchion;
A step of connecting the main girder and the strut with an arm member,
The permanent scaffolding according to any one of claims 1 to 3, wherein the main girder and the post are connected by arms, and the temporary members and the temporary wires are removed after the hanging members are permanently installed. installation method. A back panel used in the method for installing a permanent scaffold according to claim 3,
The back panel is a portion of the back panel that is supported in contact with the longitudinal beams, and a corner portion of a side that intersects the direction in which the back panel is sent out is formed of an R face or a C face. A back panel used in the method for installing a permanent scaffold according to any one of claims 1 to 3,
The back panel is provided with a fall-off prevention part that engages with an edge portion extending in the bridge axis direction of the adjacent longitudinal beams.