JP5544788B2 - Wind curing method, scaffold - Google Patents

Description

  The present invention relates to a method for wind-curing a welded portion when a steel frame is welded up and down.

  Conventionally, as a method of constructing piers, a plurality of steel pipes are erected in the vertical direction at positions corresponding to the inside of the piers, and vertical main bars are arranged around these steel pipes, and the vertical main bars are surrounded. As described above, a hybrid slip foam method is used in which a PC strand is wound, a reaction force is taken on the upper part of the steel pipe, and a concrete pier is constructed by placing concrete in the slip foam while raising the slip foam ( For example, see Patent Document 1).

  In this construction method, when the steel pipes are connected vertically, it is necessary to weld the gap between the steel pipes in a state where the upper steel pipe is temporarily determined and held in a predetermined posture above the lower steel pipe. As a welding method for connecting steel pipes, gas shielded arc welding is used. However, gas shielded arc welding is easily affected by wind and cannot perform welding work in strong winds.

  Therefore, for example, it is conceivable to apply the wind curing method described in Patent Document 1. In this method, when the upper and lower steel pipes are welded, an umbrella-shaped support member is attached to the upper steel pipe, the upper part of the support member is covered with a sheet material, and the windproof sheet is suspended from the outer periphery of the support member. Welding is performed in a space surrounded by materials. Thereby, welding work can be performed without being influenced by wind.

Japanese Patent Laid-Open No. 11-131423

  However, when the above method is applied, since the wind does not flow into the space surrounded by the sheet material, there is a problem that the working environment is deteriorated because welding fumes and the like are accumulated inside.

  The present invention has been made in view of the above problems, and the object thereof is to prevent deterioration of the working environment without being affected by wind when welding between upper and lower steel frames. That is.

The wind curing method of the present invention is a wind curing method for welding and connecting steel frames arranged above and below, and a scaffold is attached to each of the steel frames arranged above and below so as to surround each of the steel frames. A plurality of sheet materials are suspended from the outer periphery of the scaffold attached to the steel frame so that the side portions of the adjacent sheet materials overlap each other, and the lower part thereof is fixed to the scaffold attached to the lower steel frame, and the sheet material Only the lower portions of the overlapping portions are fixed to each other.
Further, in the present invention, when the steel frames arranged above and below are welded, a scaffold is attached to each of the steel frames arranged above and below so as to surround each of the steel frames, and the outer periphery of the scaffold attached to the upper steel frame A plurality of sheet materials are suspended so that side portions of adjacent sheet materials overlap each other, and a lower portion thereof is fixed to a scaffold attached to the lower steel frame, and lower portions of the overlapping portions of the sheet materials are fixed to each other. a wind curing method of the upper and anchorage attached to steel below consists expanded metal, and wherein Rukoto paved plate onto expanded metal constituting the scaffold attached to steel of the lower To do .

Further, the scaffold of the present invention is a scaffold used when the steel frame is welded up and down, the scaffold body attached so as to surround the steel frame, and the side of the scaffold body that is suspended from the outer periphery. part is a plurality of sheet material mounted to overlap each other, and wherein the Rukoto only the lower of the overlapping portions of the sheet material is fixed to one another.

  According to the present invention, by providing a plurality of sheet materials so as to surround the scaffolds attached to the upper and lower steel frames, the upper and lower steel frames can be welded without being affected by the wind. Further, since only the lower part of the overlapped portion of the adjacent sheet materials is fixed, the wind enters between the upper sheet materials and escapes upward. For this reason, welding fume does not accumulate inside, and the working environment can be prevented from deteriorating.

It is FIG. (1) for demonstrating the method of constructing a bridge pier by the hybrid slip foam construction method of this embodiment. It is FIG. (2) for demonstrating the method of constructing a bridge pier by the hybrid slip foam construction method of this embodiment. It is FIG. (3) for demonstrating the method of constructing a pier by the hybrid slip foam construction method of this embodiment. It is FIG. (4) for demonstrating the method of constructing a bridge pier by the hybrid slip foam construction method of this embodiment. It is FIG. (5) for demonstrating the method of constructing a bridge pier by the hybrid slip foam construction method of this embodiment. It is FIG. (6) for demonstrating the method of constructing a bridge pier by the hybrid slip foam construction method of this embodiment. It is FIG. (7) for demonstrating the method of constructing a bridge pier by the hybrid slip foam construction method of this embodiment. It is FIG. (8) for demonstrating the method of constructing a bridge pier by the hybrid slip foam construction method of this embodiment. It is a top view which shows the structure of an inner scaffold and an upper outer scaffold. It is a top view which shows the structure of an intermediate | middle outer scaffold. It is a figure which shows the state which extended the sheet | seat material attached to the outer periphery of an intermediate | middle outer scaffold. It is a figure which shows the state which spread the plywood on the expanded metal of an inner scaffold.

Hereinafter, an embodiment of the wind curing method of the present invention will be described in detail with reference to the drawings, taking as an example a case where the pier is constructed by a hybrid slip foam method.
FIGS. 1-8 is a figure for demonstrating the method of constructing a pier by the hybrid slip foam construction method of this embodiment.
In constructing the pier, first, as shown in FIG. 1, the ground 10 is excavated, the first-stage steel pipe 20 is disposed in the excavated portion, and the lower end of the first-stage steel pipe 20 is buried. Build up. And the inner scaffold 110 is fixed to the intermediate part and upper part of the 1st-stage steel pipe 20, and the upper outer scaffold 130 explained in full detail behind is fixed to the upper part of the 1st-stage steel pipe 20. FIG.

  FIG. 9 is a plan view showing configurations of the inner scaffold 110 and the upper outer scaffold 130. As shown in the figure, the upper outer scaffold 130 has an inner annular steel member 131 disposed so as to surround the outer periphery of the plurality of steel pipes 20 and an octagonal shape disposed around the inner annular steel member 131. An outer steel material 132, a steel material 133 connecting these annular steel materials, and a scaffolding plate (not shown) made of, for example, expanded metal, laid above the steel materials 131, 132, 133 are provided. A handrail is provided on the outer periphery of the upper outer scaffold 130.

  The inner scaffold 110 includes a steel material (not shown) assembled in a lattice shape in a portion corresponding to a gap between the steel pipes 20 in a region surrounded by the upper outer scaffold 130, and an expanded metal 111 laid on these steel materials. Composed. The inner scaffold 110 is supported by a protruding member 21 attached to the outer peripheral surface of the steel pipe 20. The upper outer scaffold 130 includes a projecting member 134 that can be advanced and retracted inward, and is supported by being attached to the inner scaffold 110 by the projecting member 134.

  Next, as shown in FIG. 2, the second-stage steel pipe 20 is lifted by the crane 300, and a gap is disposed above the lowermost-stage steel pipe 20, and the second-stage steel pipe 20 is used for temporary fixing. A jig (not shown) is held above the first stage steel pipe 20 with a gap.

  Next, as shown in FIG. 3, the inner scaffold 110 is fixed to the middle part and the upper part of the second-stage steel pipe 20, and the intermediate outer scaffold 120 with the sheet material 125 attached to the outer periphery as will be described later by the crane 300. The intermediate outer scaffold 120 is fixed to the middle part of the second stage steel pipe 20 by lifting. Further, the upper outer scaffold 130 is fixed to the upper part of the second stage steel pipe 20.

  FIG. 10 is a plan view showing the configuration of the intermediate outer scaffold 120. As shown in the figure, similar to the upper outer scaffold 130, the intermediate outer scaffold 120 includes an inner annular steel member 121 arranged so as to surround the outer periphery of the plurality of steel pipes 20, and an inner annular steel member 121. The outer steel material 122 having an octagonal shape disposed on the outer periphery of the steel material, the steel material 123 connecting the annular steel materials 121 and 122, and the steel material 121, 122, and 123 laid above the steel materials 121, 122, 123, for example, from expanded metal A scaffold plate (not shown). Further, handrails are provided on each side of the outer periphery of the upper outer scaffold 130, and a sheet material 125 is attached to each handrail. Further, the intermediate outer scaffold 120 includes a projecting member 124 that can advance and retract inward, and is supported by the projecting member 124 by applying a reaction force to the inner scaffold 110.

  FIG. 11 is a diagram illustrating a state in which the sheet material 125 attached to the outer periphery of the intermediate outer scaffold 120 is developed. The sheet material 125A attached to the upper, lower, left and right sides of the intermediate outer scaffold 120 in FIG. 11 has substantially the same width as the corresponding side of the intermediate outer scaffold 120, and the sheet material 125A is suspended as will be described later. Thus, it has such a length as to reach the upper outer scaffold 130 attached to the lower steel pipe 20. Further, the sheet material 125B attached to the oblique side of the intermediate outer scaffold 120 in FIG. 11 is formed wider than the corresponding side, and the lower steel pipe 20 is in a state where the sheet material 125B is suspended. It has a length so as to reach the upper outer scaffold 130 attached to.

After the intermediate outer scaffold 120 is attached, the first and second steel pipes 20 are welded. FIG. 4 is a view showing a state when the steel pipe 20 is welded. As shown in the figure, when welding is performed, the sheet material 125 attached to the handrail of the intermediate outer scaffold 120 is suspended, and the lower end portion of the sheet material 125 is attached to the upper portion of the first stage steel pipe 20. It is fixed to the handrail of the upper outer scaffold 130. In addition, the overlapping adjacent sheet members 125 are fixed by clips or the like within a height range where the worker can reach on the upper outer scaffold 130 attached to the upper part of the first-stage steel pipe 20.
In addition, as shown in FIG. 12, a plywood 112 is spread over the expanded metal 111 of the inner scaffold 110 attached to the upper part of the first stage steel pipe 20 without any gap.

  Then, on the inner scaffold 110 attached to the upper part of the first-stage steel pipe 20, the first-stage and second-stage steel pipes 20 are welded. At this time, the sheet material 125 blocks the space between the upper outer scaffold 130 attached to the upper part of the first stage steel pipe 20 and the intermediate outer scaffold 120 attached to the middle of the second stage steel pipe 20 as described above. Therefore, it is possible to prevent wind from blowing from the surroundings. Furthermore, since the plywood 112 is spread over the inner scaffold 110 attached to the upper part of the first stage steel pipe 20, it is possible to prevent wind from blowing from below. For this reason, the gas arc welding for connecting the steel pipe 20 can be performed smoothly without being influenced by the wind.

  The adjacent sheet members 125 are clipped at the bottom as described above, but only overlap each other at the top. As a result, when the wind is strong, the wind enters the inside from the overlapped portion of the upper portions of the adjacent sheet materials 125, so there is no possibility that the sheet material 125 will be damaged by an excessive wind load even during the strong wind. Further, since the plywood 112 is spread and closed on the inner scaffold 110 attached to the upper part of the first-stage steel pipe 20, the wind entering from the overlapped portion of the sheet material 125 is the second-stage steel pipe 20 It passes through the gap of the expanded metal 111 of the inner scaffold 110 attached to the middle part of the inner part of the inner scaffold 110 and passes upward. For this reason, there is no influence on the welding work below, and welding fumes generated in the welding work due to the flow of the wind in this way are discharged to the outside.

  After connecting the first-stage and second-stage steel pipes 20 as described above, in the inner scaffold 110 attached to the upper part of the first stage, the middle part of the second stage, and the upper part as shown in FIG. The vertical bars 30 are arranged so as to surround the steel pipe (on the outer periphery of the inner scaffold 110).

Next, the intermediate outer scaffold 120 and the upper outer scaffold 130 of the second-stage steel pipe 20 are lifted by the crane 300 and removed. The removed intermediate outer scaffold 120 and upper outer scaffold 130 can be used when welding the steel pipe 20 of the next stage. Then, as shown in FIG. 6, the upper outer scaffold 130 attached to the first stage steel pipe 20 is raised and fixed to the upper part of the second stage steel pipe 20.
In this way, by repeating the steps described with reference to FIGS. 2 to 6, the steel pipe 20 is welded upward and the vertical bars 30 are arranged.

  Then, after the connection work of the uppermost steel pipe 20 is completed, as shown in FIG. 7, a reaction force stand 200 is provided on the uppermost portion of the steel pipe 20 and the slip foam device 210 is suspended by the reaction force stand 200. Is installed. In addition, a feeding device 220 for winding the PC strand is provided on the slip foam device 210.

Next, the PC strand 40 is wound around the longitudinal bars 30 by the delivery device 220 at the upper part while the slip foam device 210 is raised. In parallel with this, the slip foam apparatus 210 is used as a mold, and the slip foam apparatus 210 is raised while placing concrete around the portion where the PC strand 40 is wound. In addition, although the inner scaffold 110 will be embed | buried in concrete, since an inner scaffold consists of an expanded metal as mentioned above, since concrete can pass through a mesh, it can lay concrete continuously. it can. After the concrete placement to the uppermost part of the pier is completed and the placed concrete is hardened, the slip foam device is lowered to the ground level and removed, and the reaction platform 200 is removed by the crane 300.
Through the above steps, the pier can be constructed as shown in FIG.

  According to the present embodiment, when welding the upper and lower steel pipes 20, the sheet material 125 is provided between the intermediate outer scaffold 120 attached to the upper steel pipe 20 and the upper outer scaffold 130 attached to the lower steel pipe 20. Therefore, when the upper and lower steel pipes 20 are gas arc welded, they can be constructed without being affected by wind.

  Moreover, since the plywood 112 was laid on the expanded metal 111 which comprises the inner scaffold 110 attached to the upper part of the lower steel pipe 20, the wind blown from the downward direction can be prevented.

  Further, since the adjacent sheet members 125 are clipped at the lower part and overlapped only at the upper part, the wind blown in the horizontal direction enters the inside through the gap between the overlapping parts of the upper part of the sheet member 125. For this reason, even during a strong wind, it is possible to prevent an excessive wind load from acting on the sheet material 125 and to prevent the sheet material 125 from being damaged.

  Further, since the wind that has entered through the gap in the upper part of the sheet material 125 is closed by the plywood, the expanded metal 111 constituting the inner scaffold 110 attached to the upper part of the lower steel pipe 20 is closed. It will blow through the gap of the expanded metal 111 of the inner scaffold 110 attached to the middle part. For this reason, the wind that has entered the inside does not interfere with the welding operation, and further, welding fumes generated by welding are discharged to the outside, and the working environment can be prevented from deteriorating.

  In the present embodiment, the sheet material 125 is suspended from the intermediate outer scaffold 120 attached to the middle portion of the upper steel pipe 20, and the lower portion of the sheet material 125 is fixed to the upper outer scaffold 130 attached to the upper portion of the lower steel pipe 20. However, the mounting position of these outer scaffolds is not limited to this, and if the outer scaffolds are respectively attached to the upper steel pipe 20 and the lower steel pipe 20, the seats from the outer scaffolds attached to the upper steel pipe 20 are used. The welded portion of the upper and lower steel pipes 20 can be surrounded by hanging the material 125 and fixing the lower part of the sheet material to an outer scaffold attached to the lower steel pipe 20.

  Moreover, in this embodiment, although the case where the steel pier which was weld-connected in the up-down direction was constructed as an example was built, the steel frame such as a square steel pipe or H-shaped steel is not limited to this. The present invention can be applied even when a linked pier is constructed.

DESCRIPTION OF SYMBOLS 10 Foundation 20 Steel pipe 30 Vertical bar 40 PC strand 110 Inner scaffold 111 Expanded metal 112 Plywood 120 Intermediate outer scaffold 121,122,123 Steel material 124,134 Protruding member 125 Sheet material 130 Upper outer scaffold 200 Reaction force stand 210 Slip form device 220 Winding Equipment 300 crane

Claims (3)

A wind curing method for welding and connecting steel frames arranged above and below,
Attach a scaffold to each of the steel frames arranged above and below to surround the steel frame,
A plurality of sheet materials are suspended from the outer periphery of the scaffold attached to the upper steel frame so that the side portions of adjacent sheet materials overlap each other, and the lower part thereof is fixed to the scaffold attached to the lower steel frame,
Only the lower part of the overlapping part of the said sheet material is mutually fixed, The wind curing method characterized by the above-mentioned. When welding steel frames placed on top and bottom,
Attach a scaffold to each of the steel frames arranged above and below to surround the steel frame,
A plurality of sheet materials are suspended from the outer periphery of the scaffold attached to the upper steel frame so that the side portions of adjacent sheet materials overlap each other, and the lower part thereof is fixed to the scaffold attached to the lower steel frame, A wind curing method for fixing the lower portions of the overlapping portions of the sheet materials to each other ,
The scaffolds attached to the upper and lower steel frames are made of expanded metal,
A wind curing method, wherein a plate material is spread on an expanded metal constituting a scaffold attached to the lower steel frame. It is a scaffold used when welding steel frames up and down,
A scaffold body attached to surround the steel frame;
The outer periphery of the scaffold body, characterized Rukoto a plurality of sheet material side in a state of being suspended from the outer periphery is mounted to overlap each other, only the lower portion of the overlapping portions of the sheet material is fixed to one another Scaffolding.

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