JPH0381457A - Work scaffold in deep foundation method - Google Patents

Abstract

PURPOSE:To enable work scaffolds to be set up and removed quickly and safely by piling up scaffold units in order wherein each unit is made up out of a work stand which is smaller in outer diameter than the inner diameter of a vertical shaft and is furnished with a center hole opened for workers to pass through, support legs and of a ladder. CONSTITUTION:Each scaffold unit 1 and 1 is made up out of a work stand 2 which is smaller in outer diameter than the inner diameter of a vertical shaft and is furnished with a center hole 6 opened for workers to pass through, a plurality of legs 3 supporting said stand, and of a ladder 5 provided in the vicinity of the center hole 6. In the second place, the lowermost scaffold unit 1 and 1 is hanged down in order to be set up on the base concrete placed on the bottom of the hole. Following which, the upper scaffold units 1 and 1 are piled up in order so that the respective legs 3 are connected in the vertical direction so as to be fixed. In addition, a crane mast 7 is set up at the uppermost section of the group of the piled-up scaffolds.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a simple work scaffold for deep foundation construction.

<Conventional technology> When constructing piles with a large diameter, the deep foundation method is used.

This construction method involves workers descending into the interior to excavate and remove soil while protecting the surrounding soil from collapsing.It is characterized by the ability to construct large-diameter piles without the use of large machinery. We are prepared.

<Problems to be Solved by the Present Invention> However, there are problems in workability and safety when assembling reinforcing bars after excavation is completed.

That is, after excavation is completed, reinforcing bars must be assembled, but it is not easy to assemble vertical bars or hoop bars that weigh more than 100 kg around the reinforcing bars in a mine that is 10 meters or more deep.

For this reason, methods such as suspending a disk-shaped scaffold from above and working on it, or attaching safety belts to ropes placed vertically, and so on, have been adopted.

However, with the method of horizontally suspending a disc-shaped scaffold inside a shaft, it is difficult to secure the scaffold to the surrounding area. Therefore, scaffolds suspended in the air were unstable and had poor functionality.

Also, since the footing is unstable, the hole t+ below it It was impossible to work at the bottom.

The combination of a robe and a safety belt allows the worker to work while securing his or her body.

Therefore, when changing the working position, the movement is not smooth, resulting in extremely poor workability.

<Purpose of the present invention> The present invention was made to solve the above-mentioned problems, and its purpose is to provide a work scaffold for the deep foundation construction method that is safe for workers and the surrounding area and has good workability. do.

<Means for solving the problem> In other words, the present invention is a scaffold used in a deep foundation construction method in which a shaft is excavated in the vertical direction while preventing the collapse of surrounding earth and sand, and one unit of the scaffold is: It consists of a work plate that has an outer diameter smaller than the inner diameter of the shaft and has a passage hole for workers in the center, a plurality of legs that support this work plate, and a ladder installed near the center hole. , this single unit of scaffolding is stacked one by one by connecting the legs in the vertical direction, and a crane is placed at the top of the stacked scaffold group, making it a working scaffold for the deep foundation construction method.

<Description of the present invention> The present invention will be explained in detail below.

<A> Deep foundation construction method The fIIIi construction method is a construction method in which a liner plate P is pasted around the shaft in parallel with the excavation of the shaft, and the bottom of the shaft is excavated while preventing the surrounding earth and sand from collapsing.

〈Mouth〉Single scaffolding The scaffolding unit 1 is composed of a workbench 2 and legs 3.

The workbench 2 is a disk made of wire mesh and other materials, and has enough strength to not be damaged even when a worker handles a heavy object on it.

The outer diameter of this workbench 2 is formed smaller than the inner diameter of the liner plate of the shaft.

A central hole 6 is opened in the center of the workbench 2.

The inner diameter of this central hole 6 is configured to a size that allows an operator to easily enter and exit.

On the other hand, the legs 3 are composed of a plurality of rod-shaped bodies fixed to the lower surface of the workbench 2.

The height of #3 is formed to be somewhat higher than the height of the worker.

The upper end of the leg 3 and its lower end are formed in a structure that can be connected when stacked one after another.

A plurality of cross members 4 are arranged on a part of the legs 3 to provide reinforcement between the legs 3.

<C> Ladder A ladder 5 is installed between the legs 3.

This ladder 5 is installed at a position where it can be used when going up and down through the central hole 6 of the workbench 2.

<Action of the present invention> Hereinafter, the operation of the present invention will be explained in detail.

<B> During excavation, the bottom of the shaft is excavated and earth is removed, and as the work progresses, liner plates P are assembled on the surrounding walls to prevent earth and sand from collapsing.

<Entrance> When the bottom of the scaffold assembly hole reaches the specified depth, concrete for the foundation is poured.

Then, the first stage scaffolding unit 1 is installed on the foundation concrete.

This installation work is carried out by suspending the scaffolding unit 1 from the upper part of the shaft.

After the installation of the first-stage scaffold unit 1 is completed, the second-stage scaffolding vehicle body l is lowered onto it.

Then, the lower end of the leg of the upper scaffold 1 is fitted into the head of the leg 3 of the lower scaffold 1, and the two are fixed together.

In this way, the legs are sequentially connected in the vertical direction and assembled upward.

Then, every few stages are connected to anchors embedded in the surrounding liner plate P etc. using wires, etc. to ensure stability.

<C> Crane assembly The assembly of the single scaffold 10 is completed when the work platform 2 approaches the ground surface.

The topmost workbench 2 is set at the same height as the ground surface.

A crane mast 7 is installed above the topmost workbench 2.

This crane mast 7 can be constituted by a frame body formed only from the legs 3 of the single scaffold 1.

A vertical shaft is attached to the upper end of this crane mast 7,
An arm 9 rotatable in a horizontal plane about this vertical axis is mounted horizontally.

A counterweight is mounted on one end of this arm 9,
A hoist or other hoist is attached to the other side so that it can be moved.

<C> After the entire scaffolding by stacking the scaffolding units 1 is completed in the shaft by the work beyond assembling the reinforcing bars, workers are placed on the work benches 2 at each stage and the reinforcing bars are successively lowered from above.

In this case, the reinforcing bars can be handled by the arm 9 on the crane mast 7, so the work is safe and quick.

On the workbench 2, the worker can handle the reinforcing bars suspended from the arm 9 in a stable state and posture, and can bind the vertical and horizontal reinforcing bars located in front of him.

Work on the same item can be done by simply moving on the workbench 2 along the wall surface.

Binding work at locations with different heights is continued by using a ladder 5 to go up and down from the central hole 6 to the scaffolding unit 1 at another level.

(2) Dismantling the scaffolding Once the reinforcing bars have been assembled, the scaffolding will be removed to allow concrete to be poured.

Even in that case, since the entire scaffold is composed of multiple stages of single scaffolds 1, it can be lifted upward and dismantled very easily.

<Example> The scaffold described above can be used, for example, in a deep foundation with an inner diameter of 3 meters and a depth of about 20 meters.

If you install reinforcing bars in one step inside the liner plate,
As long as there is a gap of about 30 cm between the edge of the workbench 2 and the inside of the liner plate P, there will be no problem in working.

The length of the legs 3, that is, the upper workbench 2 and the lower workbench 2
The distance can be set to about 1.8 to 2.0 meters.

Effects of the Present Invention Since the present invention has the above configuration, the following effects can be obtained.

(a) Once the bottom of the hole has been excavated, the entire scaffold can be assembled at once by lowering the individual scaffolds one by one.

Therefore, compared to the method of assembling parts in a shaft, the work is faster and more reliable.

<Mouth> The scaffold itself is an existing item manufactured in a factory.

Therefore, compared to on-site assembly methods, the scaffolding is more reliable and allows for safer work.

<C> Scaffolding is placed along the wall, and a space is secured in the center of the shaft by a central hole.

Therefore, work on the central part of the hole bottom can be carried out safely.

(2) Once the scaffolding is completed, the crane mast can be assembled above it.

Therefore, it is possible to safely and quickly handle and bundle a group of heavy reinforcing bars in a narrow work space.

<E> Once the reinforcing bars have been assembled, the scaffolding will need to be dismantled.

Even in that case, the work is safe and easy because the scaffolding can be easily dismantled by pulling it up one by one.

[Brief explanation of drawings]

Fig. 1: Perspective view of a single unit constituting the scaffold of the present invention Fig. 2:
An explanatory diagram of its usage condition Figure 3: An explanatory diagram of its working condition

Claims (1)

[Claims] (1) Scaffolding used in the deep foundation method of vertically excavating a shaft while preventing the collapse of surrounding earth and sand, where one unit of scaffolding has an outer diameter smaller than the inner diameter of the shaft, It consists of a work plate with a hole for workers to pass through in the center, multiple legs to support this work plate, and a ladder installed almost perpendicularly from near the center hole. Work scaffolding used in the deep foundation construction method, in which scaffolds are connected vertically and stacked one after another, and a crane is placed at the top of the stacked scaffolding group.