JP2855210B2 - Work scaffolding in the deep foundation method - Google Patents

Description

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

<Conventional technology> When building piles having a large diameter, a deep foundation method is employed.

This method is a method in which workers descend inside and excavate and discharge soil while protecting the surrounding soil from collapsing.The feature is that large-diameter piles can be constructed without using large machines. Have.

<Problems to be Solved by the Present Invention> However, rebar assembly after completion of excavation has problems in workability and safety.

In other words, rebar must be assembled after excavation is completed, but in a mine with a depth of 10 meters or more,
It is not easy to assemble vertical and hoop muscles weighing more than 100 kg.

Therefore, assembling a bitty scaffold from the bottom of the hole and working around the scaffold, hanging a disc-shaped scaffold from above, working on it, attaching a safety belt to ropes arranged vertically and working Method, etc. are adopted.

However, in the method of assembling the scaffold from the bottom of the hole, the scaffold is assembled from the bottom to the top where the excavation is completed, so that a large amount of labor is required for the assembling and dismantling work.

It is difficult to fix the scaffold around by a method of suspending the disc-shaped scaffold horizontally inside the shaft. Thus, the scaffold suspended in the air was unstable and poorly operable.

In addition, because the scaffold was unstable, work at the bottom of the hole below it was impossible.

In a combination of a rope and a safety belt, a worker works while fixing his body.

Therefore, when the work position is changed, the movement is not smooth, and the workability is extremely poor.

<Object of the present invention> The present invention has been made in order to solve the above-described problems, and aims to provide a work scaffold in a deep foundation method in which both workers and surroundings are safe and workability is good. I do.

<Means for Solving the Problems> That is, the present invention is a scaffold used in a deep foundation method of excavating in the vertical direction while preventing collapse of surrounding earth and sand, and is formed in a ring around an edge around a hole. A laid annular rail,
A moving table that moves along the annular rail, a ladder that hangs down from the moving table, and extends the lower end as the hole bottom decreases, and a work table arranged at an appropriate position on the ladder. , A working scaffold in the deep foundation method.

<Description of the Present Invention> Hereinafter, the present invention will be described in detail.

<B> Deep foundation method The deep foundation method is a method in which a liner plate P is attached around the shaft in parallel with the excavation of the shaft to excavate the bottom of the hole while preventing collapse of the surrounding earth and sand.

Prior to the excavation of the shaft, the foundation concrete 1 is placed annularly at the edge of the hole to prevent collapse.

<B> Ring rail A ring rail 2 is laid on the foundation concrete 1.

The annular rail 2 is an annular rail surrounding the pit of the shaft.

<C> Mobile platform The mobile platform 3 is mounted on the annular rail 2.

The movable base 3 is provided with wheels on its legs, and is movable on the annular rail 2.

The number of the movable bases 3 may be one, but it is more stable if a plurality of movable bases 3 are arranged at equal positions.

If the plurality of movable tables 3 are connected by the frame 4, the mutual positional relationship can be always maintained constant.

The inside of the moving table 3 is positioned so as to protrude into the upper space of the shaft.

<D> Ladder A ladder 5 is vertically attached to the overhanging side of each moving base 3.

Therefore, the lower end of the ladder 5 is vertically suspended inside the shaft.

The length of the ladder 5 is such that the lower bridge reaches the bottom of the hole.

Therefore, as the excavation of the hole progresses, the lower end thereof is extended.

<E> Worktable The worktable 6 is attached inside the ladder 5, that is, on the liner plate side.

The work table 6 is a horizontal plate, and a protective fence is fixed around the work table 6.

The worktables 6 are arranged at appropriate intervals in the vertical direction to facilitate the work.

In order for the worker on the worktable 6 to work freely, an appropriate distance is required between the worktable 6 and the liner plate. This distance is the overhang distance of the movable table 3 described above.

The ladders 5 suspended from the plurality of movable tables 3 are connected to each other by a reinforcing ring 7 or the like.

Then, the swing of the ladder 5 can be prevented, and a stable position can be secured.

<Operation of the Present Invention> Hereinafter, the operation of the present invention will be described in detail.

<A> Excavation The lower end of the ladder 5 is added and extended sequentially as the shaft is excavated.

The addition of the lower end of the ladder 5 is simple because it can be performed at the bottom of the hole.

The work table 6 is attached at an appropriate position according to the extension of the ladder 5.

<B> Assembling the rebar When the excavation work is completed, the rebar is set up inside the liner plate P and assembled.

For this purpose, bottom concrete is cast at the bottom of the hole, and several vertical bars of the present invention are suspended vertically from above.

Next, the hoops are hung down and connected to the vertical streaks. A vertical muscle is further connected to the hoop muscle.

In this way, a circular rebar basket composed of vertical and horizontal streaks is formed along the wall surface of the shaft.

In this work, since the worker is on standby at each worktable 6, the vertical and horizontal streaks can be bound efficiently and reliably on a stable scaffold.

When moving the binding position, moving the movable platform 3 on the annular rail 2 rotates the entire configuration including the ladder 5, and each work platform 6 rotates along the wall surface.

 Thus, the binding of the reinforcing bar group at all positions is completed.

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

Assuming that reinforcing bars are assembled in two steps inside the liner plate, there is no problem in operation if a space of about 42 cm is provided between the front end of the worktable 6 and the inside of the liner plate.

<Effects of the Present Invention> The present invention has the above-described configuration, and therefore the following effects can be obtained.

<a> This is a structure in which the lower end of the ladder is added in parallel with the excavation of the hole bottom.

Therefore, as compared with the construction method in which the scaffold is assembled from the hole bottom after the excavation is completed, the scaffold installation work is extremely easy and safe.

<B> The scaffold is composed of ladders that hang vertically along the wall.

Therefore, it is much safer than a work in which a plate is suspended in the air and the plate is used as a scaffold.

<C> The scaffolding is located along the wall, and the center of the shaft has space.

Therefore, the work at the center of the hole bottom can be performed safely.

<D> The entire scaffold rotates and moves along the hole wall.

Therefore, even when the work position is moved, it can be performed smoothly.

<E> The heavy load applied during the work acts on the ladder as a tensile load.

Therefore, sufficient strength can be expected with a simple structure as compared with a bite scaffold that supports work with a compressive load.

<F> All working platforms depend on ladders hanging down the wall.

Therefore, even when the height of the shaft is increased, there is no fear of collapse as in a scaffold assembled from the bottom of the hole.

<G> When the rebar assembly is completed, the scaffold must be dismantled.

In this case, the work is safe and easy because the ladder can be sequentially dismantled by lifting it.

[Brief description of the drawings]

 FIG. 1: Illustration of the use state of the device of the present invention FIG. 2: Cross-sectional view thereof

Claims (1)

(57) [Claims] 1. A scaffold used in a deep foundation method for excavating in a vertical direction while preventing collapse of surrounding earth and sand, comprising: a rail laid annularly around an edge around a hole; A deep foundation method, comprising: a moving platform that moves along a ladder, a ladder that hangs down from the movable platform, and extends the lower end as the hole bottom decreases, and a work table that is arranged at an appropriate position on the ladder. Working scaffold in