JPH0774507B2 - Construction method of underground wall - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for constructing an outer wall of a basement part of a building, and particularly when installing a retaining wall outside the outer wall constructing position.
The present invention relates to a method of installing earth retaining material for supporting earth pressure.

[Prior art] When excavating the underground part of a building and constructing an underground wall, a steel soil retaining material such as an H-shaped steel parent pile or sheet pile is installed outside the outer wall construction position to retain soil for excavation. It will be used as a wall and the steel retaining material will be removed after the underground wall of the building is completed. The basic structure of this construction method is well known, and in order to facilitate the removal of the soil retaining wall, especially the removal of the steel soil retaining material from the ground, the insulation between the concrete on the outer wall and the steel soil retaining material is insulated. I keep it. Therefore, it has been conventionally known to use a thin plywood board, a vinyl sheet, or the like as an insulating material for such a mountain retaining material to insulate a contact portion with concrete.

[Problems to be Solved by the Invention] In the method using the conventional insulating material as described above, an expensive material cost that cannot be recovered as the insulating material is required, and the mounting structure to the steel soil retaining material is not reliable. However, there is a risk that it will take a lot of time to install it due to the formation of gaps and the difficulty in constructing the entry corners, and it may fall off during construction work of the wall such as concrete pouring.

In order to install an insulating material on the earth retaining wall, it must be installed close to the earth retaining wall, so a special scaffold is required,
Temporary scaffolding costs are required and high-skilled craftsmen are required.

In addition, there is a risk that insulating materials, especially wooden support materials such as furring materials, may remain as foreign matter in the concrete, causing not only corrosion of the reinforcing bars themselves or of the reinforcing bars, but also defective parts in the design cross section. There is even a fear of it.

It is necessary to clean the concrete adhering to the soil retaining material after pulling it out by taking some time to clean it. There are many drawbacks such as the above, and it is inevitable that the construction period will be extended and the construction cost will be affected.

[Means for Solving the Problems] The present invention has been devised for the purpose of solving the problems described above, and to improve a method for insulating steel retaining material from steel and underground concrete for outer wall. The purpose is to rationalize the construction method of the underground wall. And the technical means adopted by the present invention is, in the construction method of the underground outer wall of the building, in particular, the foaming urethane is sprayed on the inner surface of the steel earth retaining material in contact with the underground outer wall to form the insulating layer with the underground outer wall. It is characterized by including steps. Thereby, the construction method of the underground outer wall of the present invention is based on the conventionally known construction method of the underground outer wall,
The insulating layer of urethane foam sprayed on the inner surface of the steel soil retaining material ensures insulation between the steel soil retaining material and the concrete for building the wall body, and furthermore, the steel soil retaining material can be easily and reliably pulled out, At the same time, it is possible to avoid disadvantages in terms of construction period and construction cost in the underground construction of the building.

[Operation] When the present invention is applied to the construction of the underground outer wall of a building, first, a parent pile of H-shaped steel or the like is driven from the ground at predetermined intervals on the outer peripheral portion of the outer wall of the building. . Then, as the excavation of the basement progressed, while using the inner flange of H-shaped steel, lay a horizontal sheet pile as a retaining plate,
Make up the retaining wall. Of course, as the soil retaining material made of steel, it is possible to use a series of sheet piles. At this stage, from the mobile scaffolding installed on the excavation surface of the excavation, or the passage, scaffolding, etc. on the upset cut beam installed on the top of the parent pile, urethane foamed on-site is directly applied to the entire inner surface of the parent pile. To form an insulating layer. Here, the process moves to the construction of the outer wall of the underground, and usually, the inner surface of the earth retaining wall is used as the outer formwork, concrete is poured, and the outer wall of the basement is constructed.

Next, using a machine separately prepared at the construction site, the soil retaining plate and the main pile are pulled out sequentially, and the urethane
The construction of the underground outer wall is completed while peeling off on the surface of the shape steel and leaving it in the ground.

[Example] An underground wall constructed by adopting the present invention will be described in detail based on an example shown in the drawings. FIG. 1 is a vertical sectional view of an outer wall adopting the present invention, which is shown as a part of the underground outer wall, in which 1 is the whole underground outer wall, 2 is its concrete concrete, 3 is the inside of the underground outer wall 1. The excavation space, 4 is the ground outside, and 5 is the root cut bottom of the excavation space 3. Reference numeral 10 is a temporary earth retaining wall installed outside the underground outer wall 1 of the building, 11 is an H-shaped steel parent pile as an example of a steel earth retaining material placed at predetermined intervals, and 12 is a parent. Inner flange of pile 11, 13 is flange 12
The earth retaining plate as a transverse sheet pile laid between them, 14 is an agitator that connects the tops of the parent piles 11, 15 is an agitated beam provided at a right angle to the agate 14, and 16 is provided on the cut beam 15. It is a scaffold.

In the present invention, the urethane foam 20 having a predetermined thickness is directly sprayed on the inner side flange 12 of the parent pile 11 and a part of the surface of the earth retaining plate 13 to form an insulating layer. For the construction, the root cutting bottom 5 should be appropriately discarded, and the ground should be leveled with concrete 51, and the scaffolding 16 mounted on the scaffolding 15 or the movable scaffolding 17 mounted on the scaffolding 16 should be used for easy construction. You can As shown in a part of the inset, the concrete 2 of the underground outer wall 1 is cast while the urethane foam 20 is sprayed and the clay retaining plate 13 is used as an outer mold to interpose the urethane foam 20.

Therefore, if the soil retaining plate 13 and the H-shaped steel parent pile 11 are pulled out after the construction of the underground outer wall 1, the urethane foam 20 and the concrete 2 on the inner surface are adhered to each other. 11 and 11 are separated from the urethane foam 20, and the urethane foam 20 is recovered while being left in the soil of the ground 4 without using a large external force. Further, concrete is not attached to the surface thereof, and therefore the work of cleaning and removing it is unnecessary.

[Advantage of the Invention] The present invention is to place a steel soil retaining material from the ground outside the outer wall construction position of a building, excavate inside the soil retaining material, and construct an underground outer wall, A method for constructing an underground outer wall so as to pull out a material, characterized by including a step of spraying urethane foam on the inner surface of the steel soil retaining material in contact with the underground outer wall to form an insulating layer with the underground outer wall First, all the drawbacks of the prior art are avoided, and the problems imposed on the present invention are solved. That is, not only is the material cost of urethane foam used as an insulating material low, but since its attachment to the steel soil retaining material is done by spraying work, it does not require a skilled worker such as carpenter,
There is no gap or difficulty in the construction of the corners, and the construction speed is high. Moreover, it does not fall off during construction work of the wall such as concrete pouring. In addition, the spraying work can be performed from a cutting beam or the like as the excavation progresses due to its characteristics, and no special scaffolding is required for the earth retaining wall and temporary construction costs are not required. Furthermore, even if the urethane foam of the curing material remains, it is in the soil side, not only there is no fear of corrosion, but there is no defect in the design cross section,
Since concrete is not adhered to the steel soil retaining material after it is pulled out, it is not necessary to clean the concrete by cleaning the concrete.

In short, the construction method of the underground outer wall of the present invention is based on the construction method of the conventional technology, but it has improved the insulation of the steel soil retention material in the main process, so the construction period is shorter than that of the conventional construction method. In addition, it should be an invention that has the advantage of being able to significantly reduce the construction cost and brings a revolutionary effect to the improvement of the construction method of the underground outer wall.

[Brief description of drawings]

The drawing is a vertical cross-sectional view showing a part of the underground outer wall adopting the construction method of the underground outer wall of the present invention. DESCRIPTION OF SYMBOLS 1 ... Underground outer wall, 2 ... Structural concrete, 3 ... Internal excavation space, 4 ... Ground, 4 ... Root cutting, 10 ... Soil retaining wall, 11 ... Steel retaining material, parent pile, H-shaped steel, 12 ... Inside Flange, 13 ... Cladding plate, 14 ... Raised, 15 ... Girder, 16 ... Scaffolding, 17 ... Mobile scaffolding, 20 ... Urethane foam, 51 ... Waste concrete.

Claims (1)

[Claims] 1. A steel soil retaining material is cast from the ground outside the building outer wall construction position, the inside of the soil retaining material is excavated to construct an underground outer wall, and then the soil retaining material is pulled out. The method for constructing an underground outer wall, comprising the step of spraying urethane foam on the inner surface of the steel soil retaining material in contact with the underground outer wall to form an insulating layer with the underground outer wall. Construction method.