JP6971641B2 - Permanent scaffolding for bridges - Google Patents

Description

The present invention relates to a scaffold for a bridge provided in an installation section of a beautification facility (louver) having no scaffolding function provided under the girder of the span of the bridge.

In the elevated road, as shown in FIG. 7, the underpass of the elevated road 101 constructed via the pier 100 may be used as a general road or as a public facility such as a park or a parking lot. If the back surface 101a of the girder of the elevated road 101 is exposed, there is a problem that the aesthetic appearance is spoiled and there is a problem of pollution caused by bird manure.
Therefore, in order to improve the problem of aesthetics and the problem of bird pollution, a large number of louvers (beautification equipment) 102 are conventionally attached to the lower back surface side of the elevated road 101.

For example, in an I-shaped steel bridge, as shown in FIG. 7A, a cross beam (small beam) 105 is supported by a suspension member 104 attached to a main girder 103, and the cross beam 105 is used to form a wedge-shaped cross section. A plurality of formed long hollow louvers 102 are arranged side by side in the width direction of the road.
Further, also in a box-shaped steel bridge, as shown in FIG. 7 (b), a cross beam (small beam) 108 is provided by a suspension member 107 attached to a main girder 106 composed of a box girder via a suspension piece (not shown). A plurality of long hollow louvers 102 formed in a wedge shape in cross section are juxtaposed on the cross beam 108 in the width direction of the road.

Each louver 102 is fixed to the cross beam 105.108 at a predetermined interval (for example, at an interval of 15 cm) by bolts or the like, thereby improving the aesthetic appearance and preventing the invasion of birds.

However, since the current beautification equipment does not have a scaffolding function, when conducting inspections and repairs, traffic is regulated, temporary scaffolding boards are installed, and after the work is completed, , I am trying to remove the temporary scaffolding that I installed. For this reason, traffic regulation and scaffolding installation / removal work are required, which causes problems in cost and construction period (see Patent Document 1).
Moreover, since the inspection needs to be performed regularly every few years, the same work (traffic control, installation and removal of temporary scaffolding) must be performed each time, which is very troublesome.

Japanese Unexamined Patent Publication No. 2000-234310

For this reason, it is required to provide a permanent scaffolding, but in order to provide a permanent scaffolding, a method of removing the current louver and the cross beam installed above it and installing a new scaffolding If adopted, it will be necessary to newly provide bolt mounting holes for mounting permanent scaffolding on the vertical beam side and perform bolting, which will complicate the work and maintain the existing beautified louver. Can't be done.
Therefore, in the beautified section where there is no scaffolding function while retaining the existing beautified louver, a permanent scaffolding that can be retrofitted without removing the louver or cross beam is desired. It is rare.

When retrofitting such a permanent scaffolding to a beautification section that does not have a scaffolding function for a bridge, it is conceivable to bring a steel plate or steel grating plate inside the beautification equipment and install it. If a steel plate that does not have the above is used, it becomes impossible to secure the light collection inside the beautification equipment, which hinders the inspection and repair work.
In this regard, if a grating plate having a grid-like opening is used, it is possible to secure lighting to some extent, but if a tool or the like is dropped during work, there is a risk of falling from the grid portion. In order to avoid such a danger, the upper surface of the grating plate may be covered with a steel plate, but with such a configuration, the grid-like portion opened to secure the lighting is closed. As a result, it becomes impossible to secure lighting in the beautification equipment.

The present invention has been made in view of the above circumstances, and is a scaffold that can be retrofitted to a beautification section that does not have a scaffolding function between bridge spans. The main task is to provide a permanent bridge scaffolding that is excellent in nature and can prevent falling objects.

In order to achieve the above problems, the scaffolding for a bridge according to the present invention includes a grating plate, a frame arranged above a beautification facility under the girder provided between the spans of the bridge, and the frame. It is configured to have a fixing bracket to fix the grating plate, and
The grating plate is integrally formed of a grating main body formed in a grid pattern and an end plate arranged so as to cover at least one end surface of the grating main body, and is formed of FRP having translucency as a whole. Being done
The end plate is formed with an opening for attaching the fixing bracket.
The fixing bracket is movable to be locked from below to the frame or an auxiliary plate fixed to the frame with a fixing side locking member that is locked to the grating plate from above so as to straddle the opening. It is characterized by having a side locking member and a tightening bolt for adjusting the distance between the fixed side locking member and the movable side locking member.

Therefore, since the grating plate constituting the scaffold is made of FRP, it is possible to secure the same strength as the steel grating plate while being lighter than the conventional steel grating plate. There is, it is carried in manually from the opening formed by temporarily removing the beautification equipment, laid out on the existing frame placed above the beautification equipment, and fixed to the frame with the fixing bracket. It becomes possible.

In addition, since the grating plate is entirely made of translucent FRP, it is possible to secure sufficient daylighting that does not interfere with inspection and repair work during the daytime, and it is possible to carry out construction and inspection within the girder. , It will be easy to inspect. In addition, even at night, the light of the street lamp comes in, so it is possible to secure the lighting.

Further, since the grating plate is made of FRP, it has high corrosion resistance and does not undergo electrolytic corrosion with steel materials or the like, so that no special insulation treatment is required. Moreover, since the FRP grating plate is integrally formed with a grid-like grating main body and an end plate arranged so as to cover at least one end surface of the grating main body, even if a tool or the like is dropped, the scaffolding can be used. There is no inconvenience of dropping it downward.

Here, it is desirable that the end plate is formed of FRP containing aluminum hydroxide.
By forming the end plate with FRP containing aluminum hydroxide, it is possible to secure fire resistance, and there is no inconvenience that the scaffold burns even when the work using fire is performed in the beautification equipment.

In order to improve the fire resistance, it is conceivable that the grating body is also formed of FRP containing aluminum hydroxide, but if aluminum hydroxide is contained, the viscosity becomes high and it becomes difficult to form a lattice. Further, since the grating main body is covered with an end plate, it is unlikely to be a place where it comes into direct contact with fire, so there is little demand for fire resistance. Therefore, the grating body may be formed of FRP that does not contain aluminum hydroxide, and only the end plate may be formed of FRP that contains aluminum hydroxide.

Further, when fixing the grating plate to the frame with the fixing metal fittings, the end plate is provided with an opening for attaching the fixing metal fitting as the minimum necessary opening, and the fixing metal fitting is provided with the grating so as to straddle the opening. A fixed-side locking member that locks from above to the plate, a movable-side locking member that locks from below to the frame or an auxiliary plate fixed to the frame, and these fixed-side locking members. Since it is configured to have a tightening bolt for adjusting the distance from the movable side locking member , the grating plate can be firmly fixed only by screwing the tightening bolt to the frame.

The scaffolding may be constructed by providing a grating plate so as to cover almost the entire beautification equipment. Even if almost the entire beautification equipment is covered with a grating plate in this way, the grating plate has translucency as a whole, so that there is no problem in ensuring daylighting, and there is no problem in beautifying. By covering almost the entire of the beautification equipment, it is possible to secure a wide scaffolding above the beautification equipment.

As described above, a translucent grating plate made of FRP in which a grating body formed in a grid pattern and an end plate arranged so as to cover at least one end surface of the grating body are integrally formed. The scaffolding for the bridge was formed by fixing the scaffolding to the frame located above the beautification equipment with fixing brackets, so the grating plate was temporarily removed from the beautification equipment to form an opening. It is possible to form a scaffold by manually carrying it into the girder from the girder and fixing it to the frame with fixing brackets while arranging it on the existing frame, so it is possible to maintain the existing beautification equipment and beautify it. It will be possible to easily construct a permanent scaffolding inside the chemical equipment.

In addition, since the FRP grating plate has translucency, it is possible to ensure light collection even in a closed space inside the beautification equipment, and the FRP grating plate can be used as a grid. Since it is composed of a shape-shaped grating body and an end plate that covers at least one end face of this grating body, even if a tool or the like is accidentally dropped, it will not be dropped below the scaffolding, ensuring safety. Is possible.

Further, by forming the end plate with FRP containing aluminum hydroxide, it is possible to secure the fire resistance of the scaffold.

1A and 1B are views showing a grating plate made of FRP constituting a scaffold for a bridge, FIG. 1A is a plan view thereof, and FIG. 1B is a cross-sectional view taken along the line AA of FIG. 1A. 2A and 2B are views showing a state in which a fixing bracket for fixing the grating plate to the frame is locked to the grating plate, FIG. 2A is a plan view thereof, and FIG. 2B is AA of FIG. 2A. The cross-sectional view cut by a line, (c) is a view seen from the line BB of (a). 3A and 3B are views showing a state in which a grating plate is hung between adjacent frames, FIG. 3A is a plan view thereof, and FIG. 3B is a cross-sectional view taken along the line AA of FIG. 3A. FIG. 4 is a diagram showing a state in which the grating plate is fixed to the frame using a fixing bracket, and FIG. 4A is a diagram showing a state in which the fixing bracket is locked to the frame on the side opposite to the opening side. (B) is a diagram showing a state in which the fixing bracket is locked on the opening side of the frame, and (c) is a state in which the fixing bracket is locked on the opening side and the opposite side of the frame. It is a figure which shows. FIG. 5 shows, as an example of forming a scaffolding above the beautification equipment, a scaffolding is laid over the entire surface above the beautification equipment (louver) provided under the girder of the I-girder steel bridge. This is a perspective view showing a state in which the grating is formed, and for convenience, the grating plate is partially cut out so that the beautification equipment can be seen, and the fixing metal fittings are omitted. FIG. 6 shows a case where a scaffold is formed by using an FRP grating plate used in the present invention, a case where a scaffold is formed by using a conventional steel grating plate, and a case where a scaffold is formed by using a conventional striped steel plate. It is a table comparing various matters with respect to the case of formation. 7A and 7B are views showing a conventional elevated road, FIG. 7A is a diagram showing an example of an I-shaped steel bridge, and FIG. 7B is a diagram showing an example of a box-shaped steel bridge.

Hereinafter, embodiments according to the present invention will be described with reference to the accompanying drawings.
In the beautification section of the elevated road, as described above, a large number of louvers, which are beautification equipment, are attached to the lower back side of the girder. This louver, which is well known in itself, is a long hollow one formed in a wedge shape in cross section, is attached along the extending direction of the road, and is arranged in parallel at predetermined intervals in the width direction of the road. ing.

In the beautification section of the bridge provided with such a louver, there is no scaffolding in the past, and it is hung above the beautification equipment (rubber) at a predetermined interval with respect to the main girder, and the road An existing frame consisting of a cross beam extending along the width direction, a vertical beam fixed so as to be orthogonal to the cross beam, and extending along the extending direction of the road is provided.

In order to install a permanent scaffolding in such a beautifully dressed section, the following performance is required.
(1) Use of existing beautification equipment ・ The existing frame and beautification equipment will be used without replacement, and the structure will be such that it can be installed inside the beautification equipment.
(2) Durability ・ Durability equal to or higher than that of existing inspection passages and permanent scaffolding shall be maintained.
(3) Workability-It does not require construction technology and can be constructed by a bridge construction engineer. again,
-Quality confirmation inspection is easy.
(4) Safety of structure
-Comply with the permanent scaffolding design technical data.
(5) Maintenance ・ It is possible to inspect the scaffolding itself and the beautification equipment outside the scaffolding from inside the permanent scaffolding.
-Easy maintenance in case of damage.
-It is possible to create an environment that is easy to inspect and repair (sufficient daylighting is ensured).
(6) Economic efficiency ・ The total cost (LCC) is superior to the conventional one.

In order to satisfy these requirements, in the present invention, the FRP grating plate 1 shown in FIG. 1 made of translucent glass fiber reinforced plastic (GFRP) is used as a member for constructing the scaffold. ing.

The grating plate 1 may be formed in any shape, but in this example, it is formed in a rectangular plate shape having a length of about 2 m, a width of about 1 m, and a thickness of about 4 cm, and is formed in a grid pattern. The grating main body 2 and the end plate 3 arranged on at least one end surface of the grating main body 2 are integrally formed. In the vicinity of the four corners of the end plate 3, openings 4 for attaching fixing brackets, which will be described later, are formed so as not to interfere with the grating main body 2. The entire grating plate 1 (grating body 2 and end plate 3) is formed of translucent FRP, and the aperture ratio of the grating plate 1 is 80% or more.

Here, unlike the grating main body 2, the end plate 3 is formed of FRP containing aluminum hydroxide to have fire resistance. On the other hand, the grating main body 2 does not contain aluminum hydroxide. This is because when aluminum hydroxide is contained, the clay becomes high and it becomes difficult to form it in a grid pattern. Further, in the grating plate 1 used for scaffolding, the end plate 3 is arranged on the upper side of the grating main body 2. Therefore, even when the work using fire is performed on the scaffolding, since the grating main body 2 is covered with the end plate 3, there is no request to make the grating main body 2 fire resistant.

In order to form the above-mentioned grating plate 1, the grating main body 2 is formed, and the grating main body 2 is placed on the end plate as it is before the end plate 3 is solidified at the time of forming the end plate 3. It is preferable to integrate the grating main body 2 and the end plate 3 by solidifying the end plate 3.

When the above grating plate 1 is installed, the grating plate 1 is placed on the existing frame (cross beams 105, 108) of the bridge, and then fixed to this frame by using the fixing bracket 10.

As shown in FIG. 2, the fixing bracket 10 is inserted into the opening 4 provided near the four corners of the end plate, and is locked to the end plate 3 from above so as to straddle the opening 4. The locking member 11, the movable side locking member 12 that locks from below to the existing frame or the auxiliary plate fixed to the frame, and the fixed side locking member 11 and the movable side locking member 12. It is configured to have a tightening bolt 13 for adjusting the distance.

In this example, the fixed-side locking member 11 is formed by processing a strip-shaped metal piece, and has a pair of locking portions 11a that lock to the opposite side edges of the opening 4 of the end plate 2 at both ends. It is configured to have an erection portion 11b that is fitted into the opening 4 with sufficient clearance so as to connect these locking portions. The tightening bolt 13 is rotatably provided at substantially the center of the erection portion 11b.

The movable side locking member 12 is a top portion in which a plate-shaped metal member is bent in a U-shaped cross section to connect a pair of side walls 12a and the pair of side walls to face the fixed side locking member 11. A wall 12b and a pair of side walls 12a are formed with an insertion recess 12c that is cut out in a direction substantially perpendicular to the bolt so that a locked member can be inserted. Further, a through hole 12d through which the tightening bolt 13 is inserted is formed in the top wall 12b, and a locking nut 14 into which the tightening bolt 13 through which the through hole 12d is inserted is screwed is paired below the top wall 12b. It is provided between the side walls 12a forming the above. The locking nut 14 may be fixed to the top wall 12b and integrated, or may be separate from the movable side locking member 12.

Therefore, the movable side locking member 12 of the fixing bracket 10 is inserted from the opening 4 to lock the fixed side locking member 11 to the peripheral edge of the opening 4 of the grating plate 1 and is exposed below the grating plate 1. By inserting the locked member (frame or auxiliary plate fixed to this frame) into the insertion recess 12c of the movable side locking member, and turning the tightening bolt 13 in this state to screw it into the locking nut 14. The distance between the fixed-side locking member 11 and the movable-side locking member 12 is shortened, and the grating plate 1 and the locked member are sandwiched by the fixing bracket 10.

In the above configuration, in order to install a permanent scaffolding above the beautification equipment (louver) 102 of the bridge using the above-mentioned grating plate 1, a pre-molded FRP grating plate 1 is used on an aerial work platform. Lift and temporarily remove a part of the beautification equipment (louver) 102 to form an opening, and manually carry the grating plate 1 into the beautification equipment from this opening, as shown in FIG. In addition, they are laid out on the existing frames (cross beams 105 and 108).
The beautification equipment (louver) 102 that was temporarily removed is installed in the original position after the grating is carried in.

If the frame (cross-section beams 105, 108) on which the welding plate 1 is placed is H-steel, the movable side locking member 12 of the fixing bracket 10 is directly placed on the flange of the frame from any side perpendicular to the frame. Although it can be locked, when the frame (cross beams 105, 108) is made of channel steel having a U-shaped cross section, the movable side locking member 12 is locked only from one direction perpendicular to the frame. In this example, as shown in FIG. 4, the auxiliary plate 15 formed to be wider than the width of the frame is welded to the upper surface of the frame (cross-beams 105, 108) so as not to protrude toward the open end side. Alternatively, it is fixed with a bolt (fixed so as to protrude to the side opposite to the open end of the frame), the glazing plate 1 is placed on the auxiliary plate 15, and is locked and fixed by a fixing bracket.
When the grating plates 1 are hung on such a channel steel frame, when a plurality of grating plates are arranged side by side in the direction perpendicular to the extension direction of the frame, half the width of each frame is used for the grating plates. It is preferable to place the side edge of the steel on the frame via the auxiliary plate 15 so that the boundary between the grating plate and the grating plate is substantially in the center in the width direction of the frame.

After that, the tightening bolt 13 of each fixing bracket 10 is loosened to keep the fixed side locking member 11 and the movable side locking member 12 apart from each other, and the movable side locking portion 12 of the fixing bracket 10 is placed on the end plate. The fixed side locking member 11 is inserted from the opening 4 of 3 so as to straddle the opening 4, and is fixed to the frame (cross beam 105, 108) in the insertion recess 12c of the movable side locking member 12. The auxiliary plate is inserted alone or together with the frame, and the movable side locking member 12 is locked to the auxiliary plate 15 or the frame (cross beams 105, 108) from below.

Specifically, as shown in FIG. 4, when the grating plate 1 is placed from the side opposite to the opening side of the frame, only the auxiliary plate 15 is inserted into the insertion recess 12c of the movable side locking member 12. The tightening bolt 13 is screwed into the locking nut 14 and tightened while adjusting the position appropriately, and the movable side locking member 12 is locked to the auxiliary plate 15 from below. When the grating plate 1 is placed from the opening side of the frame, the overlapped portion of the frame (cross beams 105, 108) and the auxiliary plate 15 is inserted into the insertion recess 12c of the movable side locking member 12. While adjusting the position appropriately, the tightening bolt 13 is screwed into the locking nut 14 to tighten it, and the movable side locking member 12 is locked to the frame from below.

As a result, the fixed-side locking member 11 is strongly locked to the grating plate 1, and the movable-side locking member 12 is strongly locked to the frame (cross beams 105, 108) directly or via the auxiliary plate 15. , The grating plate 1 can be firmly fixed only by screwing the tightening bolt 13 to the frame (cross beams 105, 108).

FIG. 5 shows a permanent scaffold α in the girder by laying and fixing a grating plate 1 on an existing frame (cross beam 105) so as to cover the entire upper surface of the beautification equipment (louver) 102 in the I-shaped steel bridge. It shows the formed image diagram. In this figure, an image of the scaffolding formed in the girder is shown, and the end plate 3 and the fixing bracket 10 of the grating plate 1 are omitted.
Even when the scaffolding α is formed on the entire upper surface of the beautification equipment in this way, the existing beautification equipment (louver 102) can be retained. In FIG. 5, 106 is a vertical beam fixed on the horizontal beam 105.

Therefore, the conventional temporary scaffolding is not required, and only the tightening tool is required for the tool (because no generator, electric tightening tool, etc. are required), so that the scaffolding can be easily constructed. Become. Therefore, it is possible to reduce the cost and shorten the construction period as compared with the conventional construction method of installing and removing temporary scaffolding.

Further, since the grating plate 1 is made of translucent FRP, it is bright in the daytime and easy to construct, inspect, and inspect. In addition, even at night, it is easy for the streetlight to come in. Further, since the grating plate 1 is made of FRP, it has high corrosion resistance and does not corrode, and since it does not cause electrolytic corrosion with a steel material or the like, no special insulation treatment or the like is required.
Regarding deterioration due to ultraviolet rays, there is no particular problem because the installation location is within the girder where ultraviolet rays do not directly hit, but if there is concern about deterioration due to ultraviolet rays, a gel coat or top coat is used as a grating plate. It can be handled by applying it to the surface.

Further, since the end plate 3 of the grating plate 1 has no opening portion except for the opening 4 to which the fixing bracket 10 is attached, there is no inconvenience of dropping the tool or the like below the scaffold even if the tool or the like is dropped during the work. Moreover, since the grating plate 1 is made of FRP, it is possible to perform on-site lining construction, etc. for maintenance in the event of damage while ensuring sufficient durability (easy to cut and process on-site). , Partial repair is also possible.
Including the above points, a comparison between the case where the scaffolding is formed by using the FRP grating plate 1 according to the present invention and the case where the scaffolding is formed by using the steel grating plate or the striped steel plate is shown in FIG. Will be shown in.

In the above configuration, an example in which a rectangular plate shape is used as the grating plate 1 is shown, but a triangular plate shape or a polygonal plate shape having a pentagonal shape or more may be used.
Further, although an example in which the entire grating is formed as an integral grid as the grating plate is shown, an opening may be provided or a lid may be provided in a portion other than the portion where the mounting bracket is attached.

1 Grating plate 2 Grating body 3 End plate 4 Opening 10 Fixing bracket 11 Fixed side locking member 12 Movable side locking member 13 Tightening bolt 102 Beautification equipment (louver)
105 cross beam 108 cross beam

Claims (3)

With a grating board,
The frame placed above the beautification equipment under the girder installed between the spans of the bridge, and
A fixing bracket for fixing the grating plate to the frame, and
Consists of
The grating plate is integrally formed of a grating main body formed in a grid pattern and an end plate arranged so as to cover at least one end surface of the grating main body, and is formed of FRP having translucency as a whole. Being done
The end plate is formed with an opening for attaching the fixing bracket.
The fixing bracket is movable to be locked from below to the frame or an auxiliary plate fixed to the frame with a fixing side locking member that is locked to the grating plate from above so as to straddle the opening. A scaffold for a bridge, which comprises a side locking member and a tightening bolt for adjusting the distance between the fixed side locking member and the movable side locking member. The bridge scaffold according to claim 1, wherein the end plate is made of FRP containing aluminum hydroxide. The bridge scaffold according to claim 1 or 2 , wherein the grating plate is provided so as to cover the entire beautification equipment.

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