JPH11100988A - Creating a scaffold for concrete structures - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a scaffold in a concrete structure constructed by spraying concrete on an outer surface of a membrane, and to be easily dismantled. SOLUTION: A ceiling wall 8 is formed by spraying concrete on an outer surface of an inflated membrane. Joint jigs 20 are attached to a plurality of locations on the inner surface of the film body 16, one end of a rope 22 is connected to each joint jig 20, and each rope 22 hangs downward with the film body 16 expanded. . When the blown concrete has hardened, the pressure in the closed space 18 of the film body 16 is reduced to a predetermined value, and each rope 22 is moved downward inside the closed space 18 using a winch 25 connected to the bottom 4 side. Pull,
A space 26 is secured between the inner surface of the ceiling wall 8 and the upper surface of the film body 16 such that work on the inner surface of the ceiling wall 8 can be performed, and the film body 16 is used as a scaffold.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for constructing a concrete wall by spraying concrete on the outside of a membrane.
The present invention relates to a method of creating a scaffold for working on the inner surface of a concrete wall.

[0002]

2. Description of the Related Art A closed space is formed inside a membrane by expanding the membrane, and a predetermined pressure is applied to the inside of the closed space to inflate the membrane into a predetermined shape.
(Or mortar) to form a concrete wall, and after the concrete has hardened, remove the membrane and build a concrete structure.This eliminates the need for installation and removal of formwork, shortening the construction period and reducing costs. Therefore, it is being adopted when constructing various storage tanks and the like. On the other hand, when the concrete structure is, for example, a storage tank as described above, in which water or oil is stored, an epoxy resin paint or the like is applied to the inner surface of the concrete wall, and a protective layer is applied to the inner surface of the concrete wall. Is formed. However, the work of applying such paint to the inner surface of the concrete wall involves assembling a scaffold inside the concrete structure and working on this scaffold because the upper surface of the storage tank is located high above the ground. I have to. Alternatively, the aerial work vehicle must be intruded inside, the scaffold must be lifted by the aerial work vehicle, and work must be performed on the scaffold.

[0003]

Therefore, assembling and disassembling the scaffold requires time, and when using an aerial work vehicle, an entrance / exit dedicated to the aerial work vehicle is formed in a concrete structure. After the work on the inner surface of the concrete wall has been completed, the entrance must be closed, and in any case, labor and cost are required, and some improvement has been desired. The present invention has been devised in view of the above circumstances, and an object of the present invention is to provide a scaffold that can easily form a scaffold inside a concrete structure without any labor and cost, and that can be easily dismantled. It is to provide a creation method.

[0004]

In order to achieve the above-mentioned object, the present invention provides a method for producing a closed space inside a membrane by expanding the membrane.
A predetermined pressure is applied to the inside of the closed space to expand the membrane into a predetermined shape, and in this expanded state, concrete is sprayed on the outside of the membrane to form a concrete wall. When the concrete wall is constructed so as to be detached, after the concrete is hardened, the pressure in the closed space is kept at a first pressure state lower than the pressure at the time of spraying the concrete. Pull the part inside the closed space to secure a space between the inner surface of the concrete wall and the outer surface of the membrane enough to work on the inner surface of the concrete wall, and connect the outer surface of this membrane to the inner surface of the concrete wall. It is characterized in that it is used as a work scaffold. In addition, the present invention provides, in a plurality of locations on the inner surface of the film body,
A linear member such as a rope for pulling a plurality of portions of the membrane into the closed space is attached in advance before the membrane is inflated to a predetermined shape, and the linear member is pulled. Wherein the portion of the film body is pulled. Further, the present invention is characterized in that the height of each portion of the membrane is adjusted by changing the length of each linear member to be pulled. Further, the present invention is characterized in that an opening for entering and exiting the space is formed in the concrete wall, and the opening is closed after work on the inner surface of the concrete wall is completed.

[0005] In the present invention, the membrane for forming the concrete wall is used as a scaffold as it is, so that no special members are prepared except for the linear members.
A working scaffold for the inner surface of the concrete wall can be easily formed. Further, when the work on the inner surface of the concrete wall is completed, the work scaffold is dismantled by removing the membrane, and the work scaffold is easily dismantled. Also, the height of the work scaffold can be easily adjusted by changing the length of the linear member, and various works on the inner surface of the concrete wall can be efficiently performed.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described. 1 is a cross-sectional front view of a storage tank, FIG. 2 is a cross-sectional front view of an end of a ceiling wall, FIG. 3 is an explanatory diagram for forming a scaffold, and FIG. 4 is a plan view of FIGS. As shown in FIG. 1, the concrete structure to which the present invention is applied is a storage tank 2. The storage tank 2 includes a side wall 6 erected from a concrete bottom 4 having a circular shape in plan view and a side wall. An upper end of the ceiling wall 6 is provided with a ceiling wall 8 having a spherical shape that is convex upward, and a protective layer made of an epoxy resin paint or the like is formed on an inner surface of the ceiling wall 8. The side wall 6 is shown in FIGS.
As shown in FIG. 1, the concrete formwork 10 is assembled, and concrete is poured into the concrete formwork 10, and reference numeral 12 in the figure denotes a scaffold for forming a side wall.

Next, the scaffold used to form the protective layer on the inner surface of the ceiling wall 8 will be described in detail. After the side wall 6 is formed, the ceiling wall 8 hermetically attaches the outer edge of the film body 16 to the upper end of the side wall 6 to form a closed space 18 on the bottom plate 4 inside the film body 16 and the side wall 6, Compressing air is supplied to the closed space 18 to inflate the film body 16 into a convex spherical shape, and concrete (or mortar) is sprayed on the outer surface of the film body 16 while maintaining the pressure in the closed space 18 at a predetermined value. Is formed.

[0010] Joint jigs 20 are attached to a plurality of locations on the inner surface of the film body 16, and one end of a rope 22 is connected to each joint jig 20. Accordingly, the ropes 22 hang down from a plurality of locations on the inner surface of the film body 16 in a state where the film body 16 is expanded in a spherical shape. Further, after the film body 16 is expanded into a spherical shape,
Before the concrete is sprayed on the outer surface of the film body 16, the opening forms are arranged at two places on the film body 16. Then, after the blown concrete hardens, the formwork for opening is removed, and as shown in FIG.
An entrance 24 for an operator to enter and exit the location is formed.

Next, when the concrete sprayed on the outer surface of the membrane 16 is hardened, the pressure in the closed space 18 is reduced to a predetermined value, and the pressure in the closed space 18 is maintained at this reduced value. Then, each rope 22 is pulled downward using a winch or the like connected to the side of the bottom plate 4 and below the inside of the closed space 18, so that a gap between the inner surface of the ceiling wall 8 and the upper surface of the film body 16 is obtained as shown in FIG. At the same time, a work space 26 enough to work on the inner surface of the ceiling wall 8 is secured. Then, the worker enters the work space 26 from the entrance 24 and applies an epoxy resin paint or the like to the inner surface of the ceiling wall 8 using the film body 16 as a scaffold, and a protective layer is formed on the inner surface of the ceiling wall 8. In this case, by adjusting the length of the rope 22, the height of the film body 16 is adjusted to a height that facilitates work. Furthermore, each rope 22
If the height of the film body 16 is changed stepwise in accordance with the shape of the ceiling wall 8 by adjusting the length of the ceiling wall 8, it is advantageous in performing the work more efficiently. After such work is completed, the worker retreats from the entrance 24 to the outside of the work space 26, closes the entrance 24, and returns the pressure in the closed space 18 to the atmospheric pressure.
The storage tank 2 is completed by removing the film body 16.

According to the present embodiment, the membrane 16 for forming the ceiling wall 8 is used as a scaffold as it is, so that no special members are prepared except for the members such as the ropes 22. A work platform for the inner surface of the ceiling wall 8 can be formed. After the work on the inner surface of the ceiling wall 8 is completed, the work scaffold is dismantled by removing the membrane body 16, and the scaffold is easily dismantled. Therefore, assembling and dismantling work of the scaffold as in the related art can be omitted, and a working scaffold for the inner surface of the ceiling wall 8 can be easily formed and dismantled without increasing costs. In addition, the height of the work scaffold can be adjusted using rope 2.
By changing the length of 2, the work on the inner surface of the ceiling wall 8 can be performed efficiently. Further, since the aerial work vehicle is not allowed to enter the inside, there is no need to form an entrance / exit dedicated to the aerial work vehicle in the side wall 6, and in this regard, it is possible to significantly reduce costs and contaminate the air inside the work environment. There is no risk of deterioration.

The present invention is widely applied regardless of the type of concrete structure and the shape of the concrete wall formed by the membrane.

[0012]

As is clear from the above description, the present invention
Expand the membrane body to create an enclosed space inside the membrane body, inflate the membrane body to a predetermined shape with a predetermined pressure in the closed space,
In this inflated state, concrete is sprayed on the outside of the membrane to form a concrete wall, and after the concrete is hardened, the membrane is removed from the concrete wall to construct the concrete wall. The pressure in the space is maintained at a first pressure state lower than the pressure when the concrete is sprayed, and then a plurality of portions of the membrane are pulled inside the closed space, and the inner surface of the concrete wall and the outer surface of the membrane And a space enough to work on the inner surface of the concrete wall,
The outer surface of the membrane was used as a work platform for the inner surface of the concrete wall. For this reason, in a concrete structure constructed by spraying concrete on the outer surface of the inflated membrane, a scaffold can be easily formed and dismantled easily without increasing labor and cost inside the structure.

[Brief description of the drawings]

FIG. 1 is a sectional front view of a storage tank.

FIG. 2 is a sectional front view of an end of a ceiling wall.

FIG. 3 is an explanatory diagram when a scaffold is formed.

FIG. 4 is a plan view of FIGS. 2 and 3;

[Explanation of symbols]

 2 Storage tank 4 Bottom panel 6 Side wall 8 Ceiling wall 16 Membrane 18 Closed space 20 Joint jig 22 Rope 26 Work space

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Yoshinori Shigeoka 8-21-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo Inside AHP Dome Japan Co., Ltd.

Claims (4)

[Claims] 1. A closed space is formed inside a membrane by expanding the membrane, and a predetermined pressure is applied to the inside of the closed space to inflate the membrane into a predetermined shape. When building a concrete wall by spraying concrete to form a concrete wall and removing the membrane from the concrete wall after hardening of the concrete, after hardening the concrete, the pressure in the closed space is set to the pressure at the time of spraying concrete. Lower pressure than the first
Then, pull several sections of the membrane into the closed space, and secure a space between the inner surface of the concrete wall and the outer surface of the membrane to allow work on the inner surface of the concrete wall. And using the outer surface of the membrane as a work scaffold for the inner surface of the concrete wall. 2. A plurality of linear members such as ropes for pulling the plurality of portions of the film body into the closed space are formed at a plurality of locations on the inner surface of the film body, and the film body is expanded into a predetermined shape. 2. The method for producing a scaffold in a concrete structure according to claim 1, wherein the portion of the membrane is pulled beforehand by attaching the linear member before pulling. 3. The method for creating a scaffold in a concrete structure according to claim 2, wherein the height of each portion of the membrane is adjusted by changing the pulling length of each linear member. 4. The concrete according to claim 1, wherein said concrete wall has an opening for entering and exiting said space, and said opening is closed after work on the inner surface of said concrete wall is completed. How to create a scaffold in a structure.